2016-11-12 21:32:43

by Matt Fleming

[permalink] [raw]
Subject: [GIT PULL 0/9] EFI changes for v4.10

Folks, please pull the following v4.10 material. There isn't a huge
amount of stuff here. The biggest change is the EFI dev path parser
code from Lukas to get thunderbolt working on his macbook.

[ The thunderbolt patch has been ACK'd by Andreas and given the OK to
take it through the EFI tree ]

The following changes since commit a75dcb5848359f488c32c0aef8711d9bd37a77b8:

efi/efivar_ssdt_load: Don't return success on allocation failure (2016-10-18 17:11:20 +0200)

are available in the git repository at:

git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi.git tags/efi-next

for you to fetch changes up to 9110bc036062fcd31994a35540d63f8deed22efa:

thunderbolt: Use Device ROM retrieved from EFI (2016-11-12 21:14:43 +0000)

----------------------------------------------------------------
* Fix an allocation bug in the generic EFI libstub where alignment
and adjusted size isn't taken into account - Roy Franz

* Update the EFI MAINTAINERS entry to include ARM and arm64 files and
directories - Ard Biesheuvel

* Add new feature to seed the RNG from the stashed value returned by
EFI_RNG_PROTOCOL in EFI stub and wire up for ARM/arm64 - Ard Biesheuvel

* Retrieve Apple device properties from within the EFI stub to fully
support thunderbolt devices on Apple Macbooks - Lukas Wunner

----------------------------------------------------------------
Ard Biesheuvel (4):
MAINTAINERS: Add ARM and arm64 EFI specific files to EFI subsystem
efi: Add support for seeding the RNG from a UEFI config table
efi/libstub: Add random.c to ARM build
efi/arm*: libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table

Lukas Wunner (4):
efi: Add device path parser
efi: Allow bitness-agnostic protocol calls
x86/efi: Retrieve and assign Apple device properties
thunderbolt: Use Device ROM retrieved from EFI

Roy Franz (1):
efi/libstub: Fix allocation size calculations

Documentation/kernel-parameters.txt | 5 +
MAINTAINERS | 6 +-
arch/arm/include/asm/efi.h | 3 +
arch/arm64/include/asm/efi.h | 3 +
arch/x86/boot/compressed/eboot.c | 65 +++++++
arch/x86/include/asm/efi.h | 16 +-
arch/x86/include/uapi/asm/bootparam.h | 1 +
drivers/firmware/efi/Kconfig | 18 ++
drivers/firmware/efi/Makefile | 2 +
drivers/firmware/efi/apple-properties.c | 248 +++++++++++++++++++++++++
drivers/firmware/efi/dev-path-parser.c | 203 ++++++++++++++++++++
drivers/firmware/efi/efi.c | 72 +++++++
drivers/firmware/efi/libstub/Makefile | 4 +-
drivers/firmware/efi/libstub/arm-stub.c | 2 +
drivers/firmware/efi/libstub/efi-stub-helper.c | 33 ++--
drivers/firmware/efi/libstub/efistub.h | 11 ++
drivers/firmware/efi/libstub/random.c | 56 +++++-
drivers/thunderbolt/Kconfig | 1 +
drivers/thunderbolt/eeprom.c | 43 +++++
drivers/thunderbolt/switch.c | 2 +-
include/linux/efi.h | 46 +++++
21 files changed, 808 insertions(+), 32 deletions(-)
create mode 100644 drivers/firmware/efi/apple-properties.c
create mode 100644 drivers/firmware/efi/dev-path-parser.c


2016-11-12 21:32:49

by Matt Fleming

[permalink] [raw]
Subject: [PATCH 3/9] efi: Add support for seeding the RNG from a UEFI config table

From: Ard Biesheuvel <[email protected]>

Specify a Linux specific UEFI configuration table that carries some
random bits, and use the contents during early boot to seed the kernel's
random number generator. This allows much strong random numbers to be
generated early on.

The entropy is fed to the kernel using add_device_randomness(), which is
documented as being appropriate for being called very early.

Since UEFI configuration tables may also be consumed by kexec'd kernels,
register a reboot notifier that updates the seed in the table.

Note that the config table could be generated by the EFI stub or by any
other UEFI driver or application (e.g., GRUB), but the random seed table
GUID and the associated functionality should be considered an internal
kernel interface (unless it is promoted to ABI later on)

Cc: Matt Fleming <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: Ard Biesheuvel <[email protected]>
---
drivers/firmware/efi/efi.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++
include/linux/efi.h | 8 ++++++
2 files changed, 80 insertions(+)

diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index a4944e22f294..92914801e388 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -23,7 +23,10 @@
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/io.h>
+#include <linux/kexec.h>
#include <linux/platform_device.h>
+#include <linux/random.h>
+#include <linux/reboot.h>
#include <linux/slab.h>
#include <linux/acpi.h>
#include <linux/ucs2_string.h>
@@ -48,6 +51,7 @@ struct efi __read_mostly efi = {
.esrt = EFI_INVALID_TABLE_ADDR,
.properties_table = EFI_INVALID_TABLE_ADDR,
.mem_attr_table = EFI_INVALID_TABLE_ADDR,
+ .rng_seed = EFI_INVALID_TABLE_ADDR,
};
EXPORT_SYMBOL(efi);

@@ -440,6 +444,7 @@ static __initdata efi_config_table_type_t common_tables[] = {
{EFI_SYSTEM_RESOURCE_TABLE_GUID, "ESRT", &efi.esrt},
{EFI_PROPERTIES_TABLE_GUID, "PROP", &efi.properties_table},
{EFI_MEMORY_ATTRIBUTES_TABLE_GUID, "MEMATTR", &efi.mem_attr_table},
+ {LINUX_EFI_RANDOM_SEED_TABLE_GUID, "RNG", &efi.rng_seed},
{NULL_GUID, NULL, NULL},
};

@@ -501,6 +506,29 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz,
pr_cont("\n");
set_bit(EFI_CONFIG_TABLES, &efi.flags);

+ if (efi.rng_seed != EFI_INVALID_TABLE_ADDR) {
+ struct linux_efi_random_seed *seed;
+ u32 size = 0;
+
+ seed = early_memremap(efi.rng_seed, sizeof(*seed));
+ if (seed != NULL) {
+ size = seed->size;
+ early_memunmap(seed, sizeof(*seed));
+ } else {
+ pr_err("Could not map UEFI random seed!\n");
+ }
+ if (size > 0) {
+ seed = early_memremap(efi.rng_seed,
+ sizeof(*seed) + size);
+ if (seed != NULL) {
+ add_device_randomness(seed->bits, seed->size);
+ early_memunmap(seed, sizeof(*seed) + size);
+ } else {
+ pr_err("Could not map UEFI random seed!\n");
+ }
+ }
+ }
+
/* Parse the EFI Properties table if it exists */
if (efi.properties_table != EFI_INVALID_TABLE_ADDR) {
efi_properties_table_t *tbl;
@@ -824,3 +852,47 @@ int efi_status_to_err(efi_status_t status)

return err;
}
+
+#ifdef CONFIG_KEXEC
+static int update_efi_random_seed(struct notifier_block *nb,
+ unsigned long code, void *unused)
+{
+ struct linux_efi_random_seed *seed;
+ u32 size = 0;
+
+ if (!kexec_in_progress)
+ return NOTIFY_DONE;
+
+ seed = memremap(efi.rng_seed, sizeof(*seed), MEMREMAP_WB);
+ if (seed != NULL) {
+ size = min(seed->size, 32U);
+ memunmap(seed);
+ } else {
+ pr_err("Could not map UEFI random seed!\n");
+ }
+ if (size > 0) {
+ seed = memremap(efi.rng_seed, sizeof(*seed) + size,
+ MEMREMAP_WB);
+ if (seed != NULL) {
+ seed->size = size;
+ get_random_bytes(seed->bits, seed->size);
+ memunmap(seed);
+ } else {
+ pr_err("Could not map UEFI random seed!\n");
+ }
+ }
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block efi_random_seed_nb = {
+ .notifier_call = update_efi_random_seed,
+};
+
+static int register_update_efi_random_seed(void)
+{
+ if (efi.rng_seed == EFI_INVALID_TABLE_ADDR)
+ return 0;
+ return register_reboot_notifier(&efi_random_seed_nb);
+}
+late_initcall(register_update_efi_random_seed);
+#endif
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 2d089487d2da..85e28b138cdd 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -599,6 +599,7 @@ void efi_native_runtime_setup(void);
*/
#define LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID EFI_GUID(0xe03fc20a, 0x85dc, 0x406e, 0xb9, 0x0e, 0x4a, 0xb5, 0x02, 0x37, 0x1d, 0x95)
#define LINUX_EFI_LOADER_ENTRY_GUID EFI_GUID(0x4a67b082, 0x0a4c, 0x41cf, 0xb6, 0xc7, 0x44, 0x0b, 0x29, 0xbb, 0x8c, 0x4f)
+#define LINUX_EFI_RANDOM_SEED_TABLE_GUID EFI_GUID(0x1ce1e5bc, 0x7ceb, 0x42f2, 0x81, 0xe5, 0x8a, 0xad, 0xf1, 0x80, 0xf5, 0x7b)

typedef struct {
efi_guid_t guid;
@@ -872,6 +873,7 @@ extern struct efi {
unsigned long esrt; /* ESRT table */
unsigned long properties_table; /* properties table */
unsigned long mem_attr_table; /* memory attributes table */
+ unsigned long rng_seed; /* UEFI firmware random seed */
efi_get_time_t *get_time;
efi_set_time_t *set_time;
efi_get_wakeup_time_t *get_wakeup_time;
@@ -1493,4 +1495,10 @@ efi_status_t efi_exit_boot_services(efi_system_table_t *sys_table,
struct efi_boot_memmap *map,
void *priv,
efi_exit_boot_map_processing priv_func);
+
+struct linux_efi_random_seed {
+ u32 size;
+ u8 bits[];
+};
+
#endif /* _LINUX_EFI_H */
--
2.10.0

2016-11-12 21:32:59

by Matt Fleming

[permalink] [raw]
Subject: [PATCH 8/9] x86/efi: Retrieve and assign Apple device properties

From: Lukas Wunner <[email protected]>

Apple's EFI drivers supply device properties which are needed to support
Macs optimally. They contain vital information which cannot be obtained
any other way (e.g. Thunderbolt Device ROM). They're also used to convey
the current device state so that OS drivers can pick up where EFI
drivers left (e.g. GPU mode setting).

There's an EFI driver dubbed "AAPL,PathProperties" which implements a
per-device key/value store. Other EFI drivers populate it using a custom
protocol. The macOS bootloader /System/Library/CoreServices/boot.efi
retrieves the properties with the same protocol. The kernel extension
AppleACPIPlatform.kext subsequently merges them into the I/O Kit
registry (see ioreg(8)) where they can be queried by other kernel
extensions and user space.

This commit extends the efistub to retrieve the device properties before
ExitBootServices is called. It assigns them to devices in an fs_initcall
so that they can be queried with the API in <linux/property.h>.

Note that the device properties will only be available if the kernel is
booted with the efistub. Distros should adjust their installers to
always use the efistub on Macs. grub with the "linux" directive will not
work unless the functionality of this commit is duplicated in grub.
(The "linuxefi" directive should work but is not included upstream as of
this writing.)

The custom protocol has GUID 91BD12FE-F6C3-44FB-A5B7-5122AB303AE0 and
looks like this:

typedef struct {
unsigned long version; /* 0x10000 */
efi_status_t (*get) (
IN struct apple_properties_protocol *this,
IN struct efi_dev_path *device,
IN efi_char16_t *property_name,
OUT void *buffer,
IN OUT u32 *buffer_len);
/* EFI_SUCCESS, EFI_NOT_FOUND, EFI_BUFFER_TOO_SMALL */
efi_status_t (*set) (
IN struct apple_properties_protocol *this,
IN struct efi_dev_path *device,
IN efi_char16_t *property_name,
IN void *property_value,
IN u32 property_value_len);
/* allocates copies of property name and value */
/* EFI_SUCCESS, EFI_OUT_OF_RESOURCES */
efi_status_t (*del) (
IN struct apple_properties_protocol *this,
IN struct efi_dev_path *device,
IN efi_char16_t *property_name);
/* EFI_SUCCESS, EFI_NOT_FOUND */
efi_status_t (*get_all) (
IN struct apple_properties_protocol *this,
OUT void *buffer,
IN OUT u32 *buffer_len);
/* EFI_SUCCESS, EFI_BUFFER_TOO_SMALL */
} apple_properties_protocol;

Thanks to Pedro Vilaça for this blog post which was helpful in reverse
engineering Apple's EFI drivers and bootloader:
https://reverse.put.as/2016/06/25/apple-efi-firmware-passwords-and-the-scbo-myth/

If someone at Apple is reading this, please note there's a memory leak
in your implementation of the del() function as the property struct is
freed but the name and value allocations are not.

Neither the macOS bootloader nor Apple's EFI drivers check the protocol
version, but we do to avoid breakage if it's ever changed. It's been the
same since at least OS X 10.6 (2009).

The get_all() function conveniently fills a buffer with all properties
in marshalled form which can be passed to the kernel as a setup_data
payload. The number of device properties is dynamic and can change
between a first invocation of get_all() (to determine the buffer size)
and a second invocation (to retrieve the actual buffer), hence the
peculiar loop which does not finish until the buffer size settles.
The macOS bootloader does the same.

The setup_data payload is later on unmarshalled in an fs_initcall. The
idea is that most buses instantiate devices in "subsys" initcall level
and drivers are usually bound to these devices in "device" initcall
level, so we assign the properties in-between, i.e. in "fs" initcall
level.

This assumes that devices to which properties pertain are instantiated
from a "subsys" initcall or earlier. That should always be the case
since on macOS, AppleACPIPlatformExpert::matchEFIDevicePath() only
supports ACPI and PCI nodes and we've fully scanned those buses during
"subsys" initcall level.

The second assumption is that properties are only needed from a "device"
initcall or later. Seems reasonable to me, but should this ever not work
out, an alternative approach would be to store the property sets e.g. in
a btree early during boot. Then whenever device_add() is called, an EFI
Device Path would have to be constructed for the newly added device,
and looked up in the btree. That way, the property set could be assigned
to the device immediately on instantiation. And this would also work for
devices instantiated in a deferred fashion. It seems like this approach
would be more complicated and require more code. That doesn't seem
justified without a specific use case.

For comparison, the strategy on macOS is to assign properties to objects
in the ACPI namespace (AppleACPIPlatformExpert::mergeEFIProperties()).
That approach is definitely wrong as it fails for devices not present in
the namespace: The NHI EFI driver supplies properties for attached
Thunderbolt devices, yet on Macs with Thunderbolt 1 only one device
level behind the host controller is described in the namespace.
Consequently macOS cannot assign properties for chained devices. With
Thunderbolt 2 they started to describe three device levels behind host
controllers in the namespace but this grossly inflates the SSDT and
still fails if the user daisy-chained more than three devices.

We copy the property names and values from the setup_data payload to
swappable virtual memory and afterwards make the payload available to
the page allocator. This is just for the sake of good housekeeping, it
wouldn't occupy a meaningful amount of physical memory (4444 bytes on my
machine). Only the payload is freed, not the setup_data header since
otherwise we'd break the list linkage and we cannot safely update the
predecessor's ->next link because there's no locking for the list.

The payload is currently not passed on to kexec'ed kernels, same for PCI
ROMs retrieved by setup_efi_pci(). This can be added later if there is
demand by amending setup_efi_state(). The payload can then no longer be
made available to the page allocator of course.

Tested-by: Lukas Wunner <[email protected]> [MacBookPro9,1]
Tested-by: Pierre Moreau <[email protected]> [MacBookPro11,3]
Signed-off-by: Lukas Wunner <[email protected]>
Cc: [email protected]
Cc: Pedro Vilaça <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Andreas Noever <[email protected]>
Cc: Peter Jones <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
---
Documentation/kernel-parameters.txt | 5 +
arch/x86/boot/compressed/eboot.c | 65 +++++++++
arch/x86/include/uapi/asm/bootparam.h | 1 +
drivers/firmware/efi/Kconfig | 13 ++
drivers/firmware/efi/Makefile | 1 +
drivers/firmware/efi/apple-properties.c | 248 ++++++++++++++++++++++++++++++++
include/linux/efi.h | 17 +++
7 files changed, 350 insertions(+)
create mode 100644 drivers/firmware/efi/apple-properties.c

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 37babf91f2cb..86a31dfc036e 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1062,6 +1062,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.

dscc4.setup= [NET]

+ dump_apple_properties [X86]
+ Dump name and content of EFI device properties on
+ x86 Macs. Useful for driver authors to determine
+ what data is available or for reverse-engineering.
+
dyndbg[="val"] [KNL,DYNAMIC_DEBUG]
module.dyndbg[="val"]
Enable debug messages at boot time. See
diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
index cc69e37548db..ff01c8fc76f7 100644
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -537,6 +537,69 @@ static void setup_efi_pci(struct boot_params *params)
efi_call_early(free_pool, pci_handle);
}

+static void retrieve_apple_device_properties(struct boot_params *boot_params)
+{
+ efi_guid_t guid = APPLE_PROPERTIES_PROTOCOL_GUID;
+ struct setup_data *data, *new;
+ efi_status_t status;
+ u32 size = 0;
+ void *p;
+
+ status = efi_call_early(locate_protocol, &guid, NULL, &p);
+ if (status != EFI_SUCCESS)
+ return;
+
+ if (efi_table_attr(apple_properties_protocol, version, p) != 0x10000) {
+ efi_printk(sys_table, "Unsupported properties proto version\n");
+ return;
+ }
+
+ efi_call_proto(apple_properties_protocol, get_all, p, NULL, &size);
+ if (!size)
+ return;
+
+ do {
+ status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
+ size + sizeof(struct setup_data), &new);
+ if (status != EFI_SUCCESS) {
+ efi_printk(sys_table,
+ "Failed to alloc mem for properties\n");
+ return;
+ }
+
+ status = efi_call_proto(apple_properties_protocol, get_all, p,
+ new->data, &size);
+
+ if (status == EFI_BUFFER_TOO_SMALL)
+ efi_call_early(free_pool, new);
+ } while (status == EFI_BUFFER_TOO_SMALL);
+
+ new->type = SETUP_APPLE_PROPERTIES;
+ new->len = size;
+ new->next = 0;
+
+ data = (struct setup_data *)(unsigned long)boot_params->hdr.setup_data;
+ if (!data)
+ boot_params->hdr.setup_data = (unsigned long)new;
+ else {
+ while (data->next)
+ data = (struct setup_data *)(unsigned long)data->next;
+ data->next = (unsigned long)new;
+ }
+}
+
+static void setup_quirks(struct boot_params *boot_params)
+{
+ efi_char16_t const apple[] = { 'A', 'p', 'p', 'l', 'e', 0 };
+ efi_char16_t *fw_vendor = (efi_char16_t *)(unsigned long)
+ efi_table_attr(efi_system_table, fw_vendor, sys_table);
+
+ if (!memcmp(fw_vendor, apple, sizeof(apple))) {
+ if (IS_ENABLED(CONFIG_APPLE_PROPERTIES))
+ retrieve_apple_device_properties(boot_params);
+ }
+}
+
static efi_status_t
setup_uga32(void **uga_handle, unsigned long size, u32 *width, u32 *height)
{
@@ -1098,6 +1161,8 @@ struct boot_params *efi_main(struct efi_config *c,

setup_efi_pci(boot_params);

+ setup_quirks(boot_params);
+
status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
sizeof(*gdt), (void **)&gdt);
if (status != EFI_SUCCESS) {
diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h
index c18ce67495fa..b10bf319ed20 100644
--- a/arch/x86/include/uapi/asm/bootparam.h
+++ b/arch/x86/include/uapi/asm/bootparam.h
@@ -7,6 +7,7 @@
#define SETUP_DTB 2
#define SETUP_PCI 3
#define SETUP_EFI 4
+#define SETUP_APPLE_PROPERTIES 5

/* ram_size flags */
#define RAMDISK_IMAGE_START_MASK 0x07FF
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index 893fda48fcdd..2e78b0b96d74 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -129,6 +129,19 @@ config EFI_TEST
Say Y here to enable the runtime services support via /dev/efi_test.
If unsure, say N.

+config APPLE_PROPERTIES
+ bool "Apple Device Properties"
+ depends on EFI_STUB && X86
+ select EFI_DEV_PATH_PARSER
+ select UCS2_STRING
+ help
+ Retrieve properties from EFI on Apple Macs and assign them to
+ devices, allowing for improved support of Apple hardware.
+ Properties that would otherwise be missing include the
+ Thunderbolt Device ROM and GPU configuration data.
+
+ If unsure, say Y if you have a Mac. Otherwise N.
+
endmenu

config UEFI_CPER
diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile
index 3e91ae31f9d1..ad67342313ed 100644
--- a/drivers/firmware/efi/Makefile
+++ b/drivers/firmware/efi/Makefile
@@ -22,6 +22,7 @@ obj-$(CONFIG_EFI_FAKE_MEMMAP) += fake_mem.o
obj-$(CONFIG_EFI_BOOTLOADER_CONTROL) += efibc.o
obj-$(CONFIG_EFI_TEST) += test/
obj-$(CONFIG_EFI_DEV_PATH_PARSER) += dev-path-parser.o
+obj-$(CONFIG_APPLE_PROPERTIES) += apple-properties.o

arm-obj-$(CONFIG_EFI) := arm-init.o arm-runtime.o
obj-$(CONFIG_ARM) += $(arm-obj-y)
diff --git a/drivers/firmware/efi/apple-properties.c b/drivers/firmware/efi/apple-properties.c
new file mode 100644
index 000000000000..c473f4c5ca34
--- /dev/null
+++ b/drivers/firmware/efi/apple-properties.c
@@ -0,0 +1,248 @@
+/*
+ * apple-properties.c - EFI device properties on Macs
+ * Copyright (C) 2016 Lukas Wunner <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2) as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define pr_fmt(fmt) "apple-properties: " fmt
+
+#include <linux/bootmem.h>
+#include <linux/dmi.h>
+#include <linux/efi.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+#include <linux/ucs2_string.h>
+#include <asm/setup.h>
+
+static bool dump_properties __initdata;
+
+static int __init dump_properties_enable(char *arg)
+{
+ dump_properties = true;
+ return 0;
+}
+
+__setup("dump_apple_properties", dump_properties_enable);
+
+struct dev_header {
+ u32 len;
+ u32 prop_count;
+ struct efi_dev_path path[0];
+ /*
+ * followed by key/value pairs, each key and value preceded by u32 len,
+ * len includes itself, value may be empty (in which case its len is 4)
+ */
+};
+
+struct properties_header {
+ u32 len;
+ u32 version;
+ u32 dev_count;
+ struct dev_header dev_header[0];
+};
+
+static u8 one __initdata = 1;
+
+static void __init unmarshal_key_value_pairs(struct dev_header *dev_header,
+ struct device *dev, void *ptr,
+ struct property_entry entry[])
+{
+ int i;
+
+ for (i = 0; i < dev_header->prop_count; i++) {
+ int remaining = dev_header->len - (ptr - (void *)dev_header);
+ u32 key_len, val_len;
+ char *key;
+
+ if (sizeof(key_len) > remaining)
+ break;
+
+ key_len = *(typeof(key_len) *)ptr;
+ if (key_len + sizeof(val_len) > remaining ||
+ key_len < sizeof(key_len) + sizeof(efi_char16_t) ||
+ *(efi_char16_t *)(ptr + sizeof(key_len)) == 0) {
+ dev_err(dev, "invalid property name len at %#zx\n",
+ ptr - (void *)dev_header);
+ break;
+ }
+
+ val_len = *(typeof(val_len) *)(ptr + key_len);
+ if (key_len + val_len > remaining ||
+ val_len < sizeof(val_len)) {
+ dev_err(dev, "invalid property val len at %#zx\n",
+ ptr - (void *)dev_header + key_len);
+ break;
+ }
+
+ /* 4 bytes to accommodate UTF-8 code points + null byte */
+ key = kzalloc((key_len - sizeof(key_len)) * 4 + 1, GFP_KERNEL);
+ if (!key) {
+ dev_err(dev, "cannot allocate property name\n");
+ break;
+ }
+ ucs2_as_utf8(key, ptr + sizeof(key_len),
+ key_len - sizeof(key_len));
+
+ entry[i].name = key;
+ entry[i].is_array = true;
+ entry[i].length = val_len - sizeof(val_len);
+ entry[i].pointer.raw_data = ptr + key_len + sizeof(val_len);
+ if (!entry[i].length) {
+ /* driver core doesn't accept empty properties */
+ entry[i].length = 1;
+ entry[i].pointer.raw_data = &one;
+ }
+
+ if (dump_properties) {
+ dev_info(dev, "property: %s\n", entry[i].name);
+ print_hex_dump(KERN_INFO, pr_fmt(), DUMP_PREFIX_OFFSET,
+ 16, 1, entry[i].pointer.raw_data,
+ entry[i].length, true);
+ }
+
+ ptr += key_len + val_len;
+ }
+
+ if (i != dev_header->prop_count) {
+ dev_err(dev, "got %d device properties, expected %u\n", i,
+ dev_header->prop_count);
+ print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
+ 16, 1, dev_header, dev_header->len, true);
+ return;
+ }
+
+ dev_info(dev, "assigning %d device properties\n", i);
+}
+
+static int __init unmarshal_devices(struct properties_header *properties)
+{
+ size_t offset = offsetof(struct properties_header, dev_header[0]);
+
+ while (offset + sizeof(struct dev_header) < properties->len) {
+ struct dev_header *dev_header = (void *)properties + offset;
+ struct property_entry *entry = NULL;
+ struct device *dev;
+ size_t len;
+ int ret, i;
+ void *ptr;
+
+ if (offset + dev_header->len > properties->len ||
+ dev_header->len <= sizeof(*dev_header)) {
+ pr_err("invalid len in dev_header at %#zx\n", offset);
+ return -EINVAL;
+ }
+
+ ptr = dev_header->path;
+ len = dev_header->len - sizeof(*dev_header);
+
+ dev = efi_get_device_by_path((struct efi_dev_path **)&ptr, &len);
+ if (IS_ERR(dev)) {
+ pr_err("device path parse error %ld at %#zx:\n",
+ PTR_ERR(dev), ptr - (void *)dev_header);
+ print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
+ 16, 1, dev_header, dev_header->len, true);
+ dev = NULL;
+ goto skip_device;
+ }
+
+ entry = kcalloc(dev_header->prop_count + 1, sizeof(*entry),
+ GFP_KERNEL);
+ if (!entry) {
+ dev_err(dev, "cannot allocate properties\n");
+ goto skip_device;
+ }
+
+ unmarshal_key_value_pairs(dev_header, dev, ptr, entry);
+ if (!entry[0].name)
+ goto skip_device;
+
+ ret = device_add_properties(dev, entry); /* makes deep copy */
+ if (ret)
+ dev_err(dev, "error %d assigning properties\n", ret);
+
+ for (i = 0; entry[i].name; i++)
+ kfree(entry[i].name);
+
+skip_device:
+ kfree(entry);
+ put_device(dev);
+ offset += dev_header->len;
+ }
+
+ return 0;
+}
+
+static int __init map_properties(void)
+{
+ struct properties_header *properties;
+ struct setup_data *data;
+ u32 data_len;
+ u64 pa_data;
+ int ret;
+
+ if (!dmi_match(DMI_SYS_VENDOR, "Apple Inc.") &&
+ !dmi_match(DMI_SYS_VENDOR, "Apple Computer, Inc."))
+ return 0;
+
+ pa_data = boot_params.hdr.setup_data;
+ while (pa_data) {
+ data = ioremap(pa_data, sizeof(*data));
+ if (!data) {
+ pr_err("cannot map setup_data header\n");
+ return -ENOMEM;
+ }
+
+ if (data->type != SETUP_APPLE_PROPERTIES) {
+ pa_data = data->next;
+ iounmap(data);
+ continue;
+ }
+
+ data_len = data->len;
+ iounmap(data);
+
+ data = ioremap(pa_data, sizeof(*data) + data_len);
+ if (!data) {
+ pr_err("cannot map setup_data payload\n");
+ return -ENOMEM;
+ }
+
+ properties = (struct properties_header *)data->data;
+ if (properties->version != 1) {
+ pr_err("unsupported version:\n");
+ print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
+ 16, 1, properties, data_len, true);
+ ret = -ENOTSUPP;
+ } else if (properties->len != data_len) {
+ pr_err("length mismatch, expected %u\n", data_len);
+ print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
+ 16, 1, properties, data_len, true);
+ ret = -EINVAL;
+ } else
+ ret = unmarshal_devices(properties);
+
+ /*
+ * Can only free the setup_data payload but not its header
+ * to avoid breaking the chain of ->next pointers.
+ */
+ data->len = 0;
+ iounmap(data);
+ free_bootmem_late(pa_data + sizeof(*data), data_len);
+
+ return ret;
+ }
+ return 0;
+}
+
+fs_initcall(map_properties);
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 261767212c47..a07a476178cd 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -443,6 +443,22 @@ typedef struct {
#define EFI_PCI_IO_ATTRIBUTE_VGA_PALETTE_IO_16 0x20000
#define EFI_PCI_IO_ATTRIBUTE_VGA_IO_16 0x40000

+typedef struct {
+ u32 version;
+ u32 get;
+ u32 set;
+ u32 del;
+ u32 get_all;
+} apple_properties_protocol_32_t;
+
+typedef struct {
+ u64 version;
+ u64 get;
+ u64 set;
+ u64 del;
+ u64 get_all;
+} apple_properties_protocol_64_t;
+
/*
* Types and defines for EFI ResetSystem
*/
@@ -592,6 +608,7 @@ void efi_native_runtime_setup(void);
#define EFI_RNG_ALGORITHM_RAW EFI_GUID(0xe43176d7, 0xb6e8, 0x4827, 0xb7, 0x84, 0x7f, 0xfd, 0xc4, 0xb6, 0x85, 0x61)
#define EFI_MEMORY_ATTRIBUTES_TABLE_GUID EFI_GUID(0xdcfa911d, 0x26eb, 0x469f, 0xa2, 0x20, 0x38, 0xb7, 0xdc, 0x46, 0x12, 0x20)
#define EFI_CONSOLE_OUT_DEVICE_GUID EFI_GUID(0xd3b36f2c, 0xd551, 0x11d4, 0x9a, 0x46, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d)
+#define APPLE_PROPERTIES_PROTOCOL_GUID EFI_GUID(0x91bd12fe, 0xf6c3, 0x44fb, 0xa5, 0xb7, 0x51, 0x22, 0xab, 0x30, 0x3a, 0xe0)

/*
* This GUID is used to pass to the kernel proper the struct screen_info
--
2.10.0

2016-11-12 21:33:14

by Matt Fleming

[permalink] [raw]
Subject: [PATCH 9/9] thunderbolt: Use Device ROM retrieved from EFI

From: Lukas Wunner <[email protected]>

Macs with Thunderbolt 1 do not have a unit-specific DROM: The DROM is
empty with uid 0x1000000000000. (Apple started factory-burning a unit-
specific DROM with Thunderbolt 2.)

Instead, the NHI EFI driver supplies a DROM in a device property. Use
it if available. It's only available when booting with the efistub.
If it's not available, silently fall back to our hardcoded DROM.

The size of the DROM is always 256 bytes. The number is hardcoded into
the NHI EFI driver. This commit can deal with an arbitrary size however,
just in case they ever change that.

Background information: The EFI firmware volume contains ROM files for
the NHI, GMUX and several other chips as well as key material. This
strategy allows Apple to deploy ROM or key updates by simply publishing
an EFI firmware update on their website. Drivers do not access those
files directly but rather through a file server via EFI protocol
AC5E4829-A8FD-440B-AF33-9FFE013B12D8. Files are identified by GUID, the
NHI DROM has 339370BD-CFC6-4454-8EF7-704653120818.

The NHI EFI driver amends that file with a unit-specific uid. The uid
has 64 bit but its entropy is much lower: 24 bit represent the model,
24 bit are taken from a serial number, 16 bit are fixed. The NHI EFI
driver obtains the serial number via the DataHub protocol, copies it
into the DROM, calculates the CRC and submits the result as a device
property.

A modification is needed in the resume code where we currently read the
uid of all switches in the hierarchy to detect plug events that occurred
during sleep. On Thunderbolt 1 root switches this will now lead to a
mismatch between the uid of the empty DROM and the EFI DROM. Exempt the
root switch from this check: It's built in, so the uid should never
change. However we continue to *read* the uid of the root switch, this
seems like a good way to test its reachability after resume.

Signed-off-by: Lukas Wunner <[email protected]>
Tested-by: Lukas Wunner <[email protected]> [MacBookPro9,1]
Tested-by: Pierre Moreau <[email protected]> [MacBookPro11,3]
Acked-by: Andreas Noever <[email protected]>
Cc: Pedro Vilaça <[email protected]>
Cc: Peter Jones <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
---
drivers/thunderbolt/Kconfig | 1 +
drivers/thunderbolt/eeprom.c | 43 +++++++++++++++++++++++++++++++++++++++++++
drivers/thunderbolt/switch.c | 2 +-
3 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/drivers/thunderbolt/Kconfig b/drivers/thunderbolt/Kconfig
index c121acc15bfe..0056df7f3c09 100644
--- a/drivers/thunderbolt/Kconfig
+++ b/drivers/thunderbolt/Kconfig
@@ -1,6 +1,7 @@
menuconfig THUNDERBOLT
tristate "Thunderbolt support for Apple devices"
depends on PCI
+ select APPLE_PROPERTIES
select CRC32
help
Cactus Ridge Thunderbolt Controller driver
diff --git a/drivers/thunderbolt/eeprom.c b/drivers/thunderbolt/eeprom.c
index 2b9602c2c355..6392990c984d 100644
--- a/drivers/thunderbolt/eeprom.c
+++ b/drivers/thunderbolt/eeprom.c
@@ -5,6 +5,7 @@
*/

#include <linux/crc32.h>
+#include <linux/property.h>
#include <linux/slab.h>
#include "tb.h"

@@ -360,6 +361,40 @@ static int tb_drom_parse_entries(struct tb_switch *sw)
}

/**
+ * tb_drom_copy_efi - copy drom supplied by EFI to sw->drom if present
+ */
+static int tb_drom_copy_efi(struct tb_switch *sw, u16 *size)
+{
+ struct device *dev = &sw->tb->nhi->pdev->dev;
+ int len, res;
+
+ len = device_property_read_u8_array(dev, "ThunderboltDROM", NULL, 0);
+ if (len < 0 || len < sizeof(struct tb_drom_header))
+ return -EINVAL;
+
+ sw->drom = kmalloc(len, GFP_KERNEL);
+ if (!sw->drom)
+ return -ENOMEM;
+
+ res = device_property_read_u8_array(dev, "ThunderboltDROM", sw->drom,
+ len);
+ if (res)
+ goto err;
+
+ *size = ((struct tb_drom_header *)sw->drom)->data_len +
+ TB_DROM_DATA_START;
+ if (*size > len)
+ goto err;
+
+ return 0;
+
+err:
+ kfree(sw->drom);
+ sw->drom = NULL;
+ return -EINVAL;
+}
+
+/**
* tb_drom_read - copy drom to sw->drom and parse it
*/
int tb_drom_read(struct tb_switch *sw)
@@ -374,6 +409,13 @@ int tb_drom_read(struct tb_switch *sw)

if (tb_route(sw) == 0) {
/*
+ * Apple's NHI EFI driver supplies a DROM for the root switch
+ * in a device property. Use it if available.
+ */
+ if (tb_drom_copy_efi(sw, &size) == 0)
+ goto parse;
+
+ /*
* The root switch contains only a dummy drom (header only,
* no entries). Hardcode the configuration here.
*/
@@ -418,6 +460,7 @@ int tb_drom_read(struct tb_switch *sw)
if (res)
goto err;

+parse:
header = (void *) sw->drom;

if (header->data_len + TB_DROM_DATA_START != size) {
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index 9840fdecb73b..c6f30b1695a9 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -460,7 +460,7 @@ int tb_switch_resume(struct tb_switch *sw)
tb_sw_warn(sw, "uid read failed\n");
return err;
}
- if (sw->uid != uid) {
+ if (sw != sw->tb->root_switch && sw->uid != uid) {
tb_sw_info(sw,
"changed while suspended (uid %#llx -> %#llx)\n",
sw->uid, uid);
--
2.10.0

2016-11-12 21:32:53

by Matt Fleming

[permalink] [raw]
Subject: [PATCH 7/9] efi: Allow bitness-agnostic protocol calls

From: Lukas Wunner <[email protected]>

We already have a macro to invoke boot services which on x86 adapts
automatically to the bitness of the EFI firmware: efi_call_early().

The macro allows sharing of functions across arches and bitness variants
as long as those functions only call boot services. However in practice
functions in the EFI stub contain a mix of boot services calls and
protocol calls.

Add an efi_call_proto() macro for bitness-agnostic protocol calls to
allow sharing more code across arches as well as deduplicating 32 bit
and 64 bit code paths.

On x86, implement it using a new efi_table_attr() macro for bitness-
agnostic table lookups. Refactor efi_call_early() to make use of the
same macro. (The resulting object code remains identical.)

Signed-off-by: Lukas Wunner <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Andreas Noever <[email protected]>
Cc: Peter Jones <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
---
arch/arm/include/asm/efi.h | 3 +++
arch/arm64/include/asm/efi.h | 3 +++
arch/x86/include/asm/efi.h | 16 +++++++++++-----
3 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/arch/arm/include/asm/efi.h b/arch/arm/include/asm/efi.h
index 766bf9b78160..0b06f5341b45 100644
--- a/arch/arm/include/asm/efi.h
+++ b/arch/arm/include/asm/efi.h
@@ -57,6 +57,9 @@ void efi_virtmap_unload(void);
#define __efi_call_early(f, ...) f(__VA_ARGS__)
#define efi_is_64bit() (false)

+#define efi_call_proto(protocol, f, instance, ...) \
+ ((protocol##_t *)instance)->f(instance, ##__VA_ARGS__)
+
struct screen_info *alloc_screen_info(efi_system_table_t *sys_table_arg);
void free_screen_info(efi_system_table_t *sys_table, struct screen_info *si);

diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h
index a9e54aad15ef..771b3f0bc757 100644
--- a/arch/arm64/include/asm/efi.h
+++ b/arch/arm64/include/asm/efi.h
@@ -51,6 +51,9 @@ int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md);
#define __efi_call_early(f, ...) f(__VA_ARGS__)
#define efi_is_64bit() (true)

+#define efi_call_proto(protocol, f, instance, ...) \
+ ((protocol##_t *)instance)->f(instance, ##__VA_ARGS__)
+
#define alloc_screen_info(x...) &screen_info
#define free_screen_info(x...)

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 389d700b961e..e99675b9c861 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -210,12 +210,18 @@ static inline bool efi_is_64bit(void)
return __efi_early()->is64;
}

+#define efi_table_attr(table, attr, instance) \
+ (efi_is_64bit() ? \
+ ((table##_64_t *)(unsigned long)instance)->attr : \
+ ((table##_32_t *)(unsigned long)instance)->attr)
+
+#define efi_call_proto(protocol, f, instance, ...) \
+ __efi_early()->call(efi_table_attr(protocol, f, instance), \
+ instance, ##__VA_ARGS__)
+
#define efi_call_early(f, ...) \
- __efi_early()->call(efi_is_64bit() ? \
- ((efi_boot_services_64_t *)(unsigned long) \
- __efi_early()->boot_services)->f : \
- ((efi_boot_services_32_t *)(unsigned long) \
- __efi_early()->boot_services)->f, __VA_ARGS__)
+ __efi_early()->call(efi_table_attr(efi_boot_services, f, \
+ __efi_early()->boot_services), __VA_ARGS__)

#define __efi_call_early(f, ...) \
__efi_early()->call((unsigned long)f, __VA_ARGS__);
--
2.10.0

2016-11-12 21:33:36

by Matt Fleming

[permalink] [raw]
Subject: [PATCH 6/9] efi: Add device path parser

From: Lukas Wunner <[email protected]>

We're about to extended the efistub to retrieve device properties from
EFI on Apple Macs. The properties use EFI Device Paths to indicate the
device they belong to. This commit adds a parser which, given an EFI
Device Path, locates the corresponding struct device and returns a
reference to it.

Initially only ACPI and PCI Device Path nodes are supported, these are
the only types needed for Apple device properties (the corresponding
macOS function AppleACPIPlatformExpert::matchEFIDevicePath() does not
support any others). Further node types can be added with little to
moderate effort.

Apple device properties is currently the only use case of this parser,
but Peter Jones intends to use it to match up devices with the
ConInDev/ConOutDev/ErrOutDev variables and add sysfs attributes to these
devices to say the hardware supports using them as console. Thus,
make this parser a separate component which can be selected with config
option EFI_DEV_PATH_PARSER. It can in principle be compiled as a module
if acpi_get_first_physical_node() and acpi_bus_type are exported (and
efi_get_device_by_path() itself is exported).

The dependency on CONFIG_ACPI is needed for acpi_match_device_ids().
It can be removed if an empty inline stub is added for that function.

Signed-off-by: Lukas Wunner <[email protected]>
Cc: Peter Jones <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Andreas Noever <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
---
drivers/firmware/efi/Kconfig | 5 +
drivers/firmware/efi/Makefile | 1 +
drivers/firmware/efi/dev-path-parser.c | 203 +++++++++++++++++++++++++++++++++
include/linux/efi.h | 20 ++++
4 files changed, 229 insertions(+)
create mode 100644 drivers/firmware/efi/dev-path-parser.c

diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index c981be17d3c0..893fda48fcdd 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -133,3 +133,8 @@ endmenu

config UEFI_CPER
bool
+
+config EFI_DEV_PATH_PARSER
+ bool
+ depends on ACPI
+ default n
diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile
index c8a439f6d715..3e91ae31f9d1 100644
--- a/drivers/firmware/efi/Makefile
+++ b/drivers/firmware/efi/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_EFI_STUB) += libstub/
obj-$(CONFIG_EFI_FAKE_MEMMAP) += fake_mem.o
obj-$(CONFIG_EFI_BOOTLOADER_CONTROL) += efibc.o
obj-$(CONFIG_EFI_TEST) += test/
+obj-$(CONFIG_EFI_DEV_PATH_PARSER) += dev-path-parser.o

arm-obj-$(CONFIG_EFI) := arm-init.o arm-runtime.o
obj-$(CONFIG_ARM) += $(arm-obj-y)
diff --git a/drivers/firmware/efi/dev-path-parser.c b/drivers/firmware/efi/dev-path-parser.c
new file mode 100644
index 000000000000..85d1834ee9b7
--- /dev/null
+++ b/drivers/firmware/efi/dev-path-parser.c
@@ -0,0 +1,203 @@
+/*
+ * dev-path-parser.c - EFI Device Path parser
+ * Copyright (C) 2016 Lukas Wunner <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2) as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/acpi.h>
+#include <linux/efi.h>
+#include <linux/pci.h>
+
+struct acpi_hid_uid {
+ struct acpi_device_id hid[2];
+ char uid[11]; /* UINT_MAX + null byte */
+};
+
+static int __init match_acpi_dev(struct device *dev, void *data)
+{
+ struct acpi_hid_uid hid_uid = *(struct acpi_hid_uid *)data;
+ struct acpi_device *adev = to_acpi_device(dev);
+
+ if (acpi_match_device_ids(adev, hid_uid.hid))
+ return 0;
+
+ if (adev->pnp.unique_id)
+ return !strcmp(adev->pnp.unique_id, hid_uid.uid);
+ else
+ return !strcmp("0", hid_uid.uid);
+}
+
+static long __init parse_acpi_path(struct efi_dev_path *node,
+ struct device *parent, struct device **child)
+{
+ struct acpi_hid_uid hid_uid = {};
+ struct device *phys_dev;
+
+ if (node->length != 12)
+ return -EINVAL;
+
+ sprintf(hid_uid.hid[0].id, "%c%c%c%04X",
+ 'A' + ((node->acpi.hid >> 10) & 0x1f) - 1,
+ 'A' + ((node->acpi.hid >> 5) & 0x1f) - 1,
+ 'A' + ((node->acpi.hid >> 0) & 0x1f) - 1,
+ node->acpi.hid >> 16);
+ sprintf(hid_uid.uid, "%u", node->acpi.uid);
+
+ *child = bus_find_device(&acpi_bus_type, NULL, &hid_uid,
+ match_acpi_dev);
+ if (!*child)
+ return -ENODEV;
+
+ phys_dev = acpi_get_first_physical_node(to_acpi_device(*child));
+ if (phys_dev) {
+ get_device(phys_dev);
+ put_device(*child);
+ *child = phys_dev;
+ }
+
+ return 0;
+}
+
+static int __init match_pci_dev(struct device *dev, void *data)
+{
+ unsigned int devfn = *(unsigned int *)data;
+
+ return dev_is_pci(dev) && to_pci_dev(dev)->devfn == devfn;
+}
+
+static long __init parse_pci_path(struct efi_dev_path *node,
+ struct device *parent, struct device **child)
+{
+ unsigned int devfn;
+
+ if (node->length != 6)
+ return -EINVAL;
+ if (!parent)
+ return -EINVAL;
+
+ devfn = PCI_DEVFN(node->pci.dev, node->pci.fn);
+
+ *child = device_find_child(parent, &devfn, match_pci_dev);
+ if (!*child)
+ return -ENODEV;
+
+ return 0;
+}
+
+/*
+ * Insert parsers for further node types here.
+ *
+ * Each parser takes a pointer to the @node and to the @parent (will be NULL
+ * for the first device path node). If a device corresponding to @node was
+ * found below @parent, its reference count should be incremented and the
+ * device returned in @child.
+ *
+ * The return value should be 0 on success or a negative int on failure.
+ * The special return values 0x01 (EFI_DEV_END_INSTANCE) and 0xFF
+ * (EFI_DEV_END_ENTIRE) signal the end of the device path, only
+ * parse_end_path() is supposed to return this.
+ *
+ * Be sure to validate the node length and contents before commencing the
+ * search for a device.
+ */
+
+static long __init parse_end_path(struct efi_dev_path *node,
+ struct device *parent, struct device **child)
+{
+ if (node->length != 4)
+ return -EINVAL;
+ if (node->sub_type != EFI_DEV_END_INSTANCE &&
+ node->sub_type != EFI_DEV_END_ENTIRE)
+ return -EINVAL;
+ if (!parent)
+ return -ENODEV;
+
+ *child = get_device(parent);
+ return node->sub_type;
+}
+
+/**
+ * efi_get_device_by_path - find device by EFI Device Path
+ * @node: EFI Device Path
+ * @len: maximum length of EFI Device Path in bytes
+ *
+ * Parse a series of EFI Device Path nodes at @node and find the corresponding
+ * device. If the device was found, its reference count is incremented and a
+ * pointer to it is returned. The caller needs to drop the reference with
+ * put_device() after use. The @node pointer is updated to point to the
+ * location immediately after the "End of Hardware Device Path" node.
+ *
+ * If another Device Path instance follows, @len is decremented by the number
+ * of bytes consumed. Otherwise @len is set to %0.
+ *
+ * If a Device Path node is malformed or its corresponding device is not found,
+ * @node is updated to point to this offending node and an ERR_PTR is returned.
+ *
+ * If @len is initially %0, the function returns %NULL. Thus, to iterate over
+ * all instances in a path, the following idiom may be used:
+ *
+ * while (!IS_ERR_OR_NULL(dev = efi_get_device_by_path(&node, &len))) {
+ * // do something with dev
+ * put_device(dev);
+ * }
+ * if (IS_ERR(dev))
+ * // report error
+ *
+ * Devices can only be found if they're already instantiated. Most buses
+ * instantiate devices in the "subsys" initcall level, hence the earliest
+ * initcall level in which this function should be called is "fs".
+ *
+ * Returns the device on success or
+ * %ERR_PTR(-ENODEV) if no device was found,
+ * %ERR_PTR(-EINVAL) if a node is malformed or exceeds @len,
+ * %ERR_PTR(-ENOTSUPP) if support for a node type is not yet implemented.
+ */
+struct device * __init efi_get_device_by_path(struct efi_dev_path **node,
+ size_t *len)
+{
+ struct device *parent = NULL, *child;
+ long ret = 0;
+
+ if (!*len)
+ return NULL;
+
+ while (!ret) {
+ if (*len < 4 || *len < (*node)->length)
+ ret = -EINVAL;
+ else if ((*node)->type == EFI_DEV_ACPI &&
+ (*node)->sub_type == EFI_DEV_BASIC_ACPI)
+ ret = parse_acpi_path(*node, parent, &child);
+ else if ((*node)->type == EFI_DEV_HW &&
+ (*node)->sub_type == EFI_DEV_PCI)
+ ret = parse_pci_path(*node, parent, &child);
+ else if (((*node)->type == EFI_DEV_END_PATH ||
+ (*node)->type == EFI_DEV_END_PATH2))
+ ret = parse_end_path(*node, parent, &child);
+ else
+ ret = -ENOTSUPP;
+
+ put_device(parent);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
+ parent = child;
+ *node = (void *)*node + (*node)->length;
+ *len -= (*node)->length;
+ }
+
+ if (ret == EFI_DEV_END_ENTIRE)
+ *len = 0;
+
+ return child;
+}
diff --git a/include/linux/efi.h b/include/linux/efi.h
index f5a821d9b90c..261767212c47 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -1148,6 +1148,26 @@ struct efi_generic_dev_path {
u16 length;
} __attribute ((packed));

+struct efi_dev_path {
+ u8 type; /* can be replaced with unnamed */
+ u8 sub_type; /* struct efi_generic_dev_path; */
+ u16 length; /* once we've moved to -std=c11 */
+ union {
+ struct {
+ u32 hid;
+ u32 uid;
+ } acpi;
+ struct {
+ u8 fn;
+ u8 dev;
+ } pci;
+ };
+} __attribute ((packed));
+
+#if IS_ENABLED(CONFIG_EFI_DEV_PATH_PARSER)
+struct device *efi_get_device_by_path(struct efi_dev_path **node, size_t *len);
+#endif
+
static inline void memrange_efi_to_native(u64 *addr, u64 *npages)
{
*npages = PFN_UP(*addr + (*npages<<EFI_PAGE_SHIFT)) - PFN_DOWN(*addr);
--
2.10.0

2016-11-12 21:33:56

by Matt Fleming

[permalink] [raw]
Subject: [PATCH 4/9] efi/libstub: Add random.c to ARM build

From: Ard Biesheuvel <[email protected]>

Make random.c build for ARM by moving the fallback definition of
EFI_ALLOC_ALIGN to efistub.h, and replacing a division by a value
we know to be a power of 2 with a right shift (this is required since
ARM does not have any integer division helper routines in its decompressor)

Cc: Matt Fleming <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: Ard Biesheuvel <[email protected]>
---
drivers/firmware/efi/libstub/Makefile | 4 ++--
drivers/firmware/efi/libstub/efi-stub-helper.c | 9 ---------
drivers/firmware/efi/libstub/efistub.h | 9 +++++++++
drivers/firmware/efi/libstub/random.c | 8 +++++---
4 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index c06945160a41..40ddf8f763a8 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -36,11 +36,11 @@ arm-deps := fdt_rw.c fdt_ro.c fdt_wip.c fdt.c fdt_empty_tree.c fdt_sw.c sort.c
$(obj)/lib-%.o: $(srctree)/lib/%.c FORCE
$(call if_changed_rule,cc_o_c)

-lib-$(CONFIG_EFI_ARMSTUB) += arm-stub.o fdt.o string.o \
+lib-$(CONFIG_EFI_ARMSTUB) += arm-stub.o fdt.o string.o random.o \
$(patsubst %.c,lib-%.o,$(arm-deps))

lib-$(CONFIG_ARM) += arm32-stub.o
-lib-$(CONFIG_ARM64) += arm64-stub.o random.o
+lib-$(CONFIG_ARM64) += arm64-stub.o
CFLAGS_arm64-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET)

#
diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index 4b74bf86c74d..757badc1debb 100644
--- a/drivers/firmware/efi/libstub/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
@@ -32,15 +32,6 @@

static unsigned long __chunk_size = EFI_READ_CHUNK_SIZE;

-/*
- * Allow the platform to override the allocation granularity: this allows
- * systems that have the capability to run with a larger page size to deal
- * with the allocations for initrd and fdt more efficiently.
- */
-#ifndef EFI_ALLOC_ALIGN
-#define EFI_ALLOC_ALIGN EFI_PAGE_SIZE
-#endif
-
#define EFI_MMAP_NR_SLACK_SLOTS 8

struct file_info {
diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index ee49cd23ee63..fe1f22584c69 100644
--- a/drivers/firmware/efi/libstub/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -15,6 +15,15 @@
*/
#undef __init

+/*
+ * Allow the platform to override the allocation granularity: this allows
+ * systems that have the capability to run with a larger page size to deal
+ * with the allocations for initrd and fdt more efficiently.
+ */
+#ifndef EFI_ALLOC_ALIGN
+#define EFI_ALLOC_ALIGN EFI_PAGE_SIZE
+#endif
+
void efi_char16_printk(efi_system_table_t *, efi_char16_t *);

efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg, void *__image,
diff --git a/drivers/firmware/efi/libstub/random.c b/drivers/firmware/efi/libstub/random.c
index 0c9f58c5ba50..f8e2e5ae6872 100644
--- a/drivers/firmware/efi/libstub/random.c
+++ b/drivers/firmware/efi/libstub/random.c
@@ -8,6 +8,7 @@
*/

#include <linux/efi.h>
+#include <linux/log2.h>
#include <asm/efi.h>

#include "efistub.h"
@@ -41,8 +42,9 @@ efi_status_t efi_get_random_bytes(efi_system_table_t *sys_table_arg,
*/
static unsigned long get_entry_num_slots(efi_memory_desc_t *md,
unsigned long size,
- unsigned long align)
+ unsigned long align_shift)
{
+ unsigned long align = 1UL << align_shift;
u64 start, end;

if (md->type != EFI_CONVENTIONAL_MEMORY)
@@ -55,7 +57,7 @@ static unsigned long get_entry_num_slots(efi_memory_desc_t *md,
if (start > end)
return 0;

- return (end - start + 1) / align;
+ return (end - start + 1) >> align_shift;
}

/*
@@ -98,7 +100,7 @@ efi_status_t efi_random_alloc(efi_system_table_t *sys_table_arg,
efi_memory_desc_t *md = (void *)memory_map + map_offset;
unsigned long slots;

- slots = get_entry_num_slots(md, size, align);
+ slots = get_entry_num_slots(md, size, ilog2(align));
MD_NUM_SLOTS(md) = slots;
total_slots += slots;
}
--
2.10.0

2016-11-12 21:33:55

by Matt Fleming

[permalink] [raw]
Subject: [PATCH 5/9] efi/arm*: libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table

From: Ard Biesheuvel <[email protected]>

Invoke the EFI_RNG_PROTOCOL protocol in the context of the stub and
install the Linux-specific RNG seed UEFI config table. This will be
picked up by the EFI routines in the core kernel to seed the kernel
entropy pool.

Cc: Matt Fleming <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: Ard Biesheuvel <[email protected]>
---
drivers/firmware/efi/libstub/arm-stub.c | 2 ++
drivers/firmware/efi/libstub/efistub.h | 2 ++
drivers/firmware/efi/libstub/random.c | 48 +++++++++++++++++++++++++++++++++
include/linux/efi.h | 1 +
4 files changed, 53 insertions(+)

diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c
index 993aa56755f6..b4f7d78f9e8b 100644
--- a/drivers/firmware/efi/libstub/arm-stub.c
+++ b/drivers/firmware/efi/libstub/arm-stub.c
@@ -340,6 +340,8 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table,
if (status != EFI_SUCCESS)
pr_efi_err(sys_table, "Failed initrd from command line!\n");

+ efi_random_get_seed(sys_table);
+
new_fdt_addr = fdt_addr;
status = allocate_new_fdt_and_exit_boot(sys_table, handle,
&new_fdt_addr, dram_base + MAX_FDT_OFFSET,
diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index fe1f22584c69..b98824e3800a 100644
--- a/drivers/firmware/efi/libstub/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -71,4 +71,6 @@ efi_status_t efi_random_alloc(efi_system_table_t *sys_table_arg,

efi_status_t check_platform_features(efi_system_table_t *sys_table_arg);

+efi_status_t efi_random_get_seed(efi_system_table_t *sys_table_arg);
+
#endif
diff --git a/drivers/firmware/efi/libstub/random.c b/drivers/firmware/efi/libstub/random.c
index f8e2e5ae6872..3a3feacc329f 100644
--- a/drivers/firmware/efi/libstub/random.c
+++ b/drivers/firmware/efi/libstub/random.c
@@ -143,3 +143,51 @@ efi_status_t efi_random_alloc(efi_system_table_t *sys_table_arg,

return status;
}
+
+#define RANDOM_SEED_SIZE 32
+
+efi_status_t efi_random_get_seed(efi_system_table_t *sys_table_arg)
+{
+ efi_guid_t rng_proto = EFI_RNG_PROTOCOL_GUID;
+ efi_guid_t rng_algo_raw = EFI_RNG_ALGORITHM_RAW;
+ efi_guid_t rng_table_guid = LINUX_EFI_RANDOM_SEED_TABLE_GUID;
+ struct efi_rng_protocol *rng;
+ struct linux_efi_random_seed *seed;
+ efi_status_t status;
+
+ status = efi_call_early(locate_protocol, &rng_proto, NULL,
+ (void **)&rng);
+ if (status != EFI_SUCCESS)
+ return status;
+
+ status = efi_call_early(allocate_pool, EFI_RUNTIME_SERVICES_DATA,
+ sizeof(*seed) + RANDOM_SEED_SIZE,
+ (void **)&seed);
+ if (status != EFI_SUCCESS)
+ return status;
+
+ status = rng->get_rng(rng, &rng_algo_raw, RANDOM_SEED_SIZE,
+ seed->bits);
+ if (status == EFI_UNSUPPORTED)
+ /*
+ * Use whatever algorithm we have available if the raw algorithm
+ * is not implemented.
+ */
+ status = rng->get_rng(rng, NULL, RANDOM_SEED_SIZE,
+ seed->bits);
+
+ if (status != EFI_SUCCESS)
+ goto err_freepool;
+
+ seed->size = RANDOM_SEED_SIZE;
+ status = efi_call_early(install_configuration_table, &rng_table_guid,
+ seed);
+ if (status != EFI_SUCCESS)
+ goto err_freepool;
+
+ return EFI_SUCCESS;
+
+err_freepool:
+ efi_call_early(free_pool, seed);
+ return status;
+}
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 85e28b138cdd..f5a821d9b90c 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -589,6 +589,7 @@ void efi_native_runtime_setup(void);
#define DEVICE_TREE_GUID EFI_GUID(0xb1b621d5, 0xf19c, 0x41a5, 0x83, 0x0b, 0xd9, 0x15, 0x2c, 0x69, 0xaa, 0xe0)
#define EFI_PROPERTIES_TABLE_GUID EFI_GUID(0x880aaca3, 0x4adc, 0x4a04, 0x90, 0x79, 0xb7, 0x47, 0x34, 0x08, 0x25, 0xe5)
#define EFI_RNG_PROTOCOL_GUID EFI_GUID(0x3152bca5, 0xeade, 0x433d, 0x86, 0x2e, 0xc0, 0x1c, 0xdc, 0x29, 0x1f, 0x44)
+#define EFI_RNG_ALGORITHM_RAW EFI_GUID(0xe43176d7, 0xb6e8, 0x4827, 0xb7, 0x84, 0x7f, 0xfd, 0xc4, 0xb6, 0x85, 0x61)
#define EFI_MEMORY_ATTRIBUTES_TABLE_GUID EFI_GUID(0xdcfa911d, 0x26eb, 0x469f, 0xa2, 0x20, 0x38, 0xb7, 0xdc, 0x46, 0x12, 0x20)
#define EFI_CONSOLE_OUT_DEVICE_GUID EFI_GUID(0xd3b36f2c, 0xd551, 0x11d4, 0x9a, 0x46, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d)

--
2.10.0

2016-11-12 21:34:24

by Matt Fleming

[permalink] [raw]
Subject: [PATCH 2/9] MAINTAINERS: Add ARM and arm64 EFI specific files to EFI subsystem

From: Ard Biesheuvel <[email protected]>

Since I will be co-maintaining the EFI subsystem, it makes sense to
mention the ARM and arm64 EFI bits in the EFI section in MAINTAINERS
so that Matt, the list and I get cc'ed on proposed changes.

Acked-by: Will Deacon <[email protected]>
Acked-by: Russell King <[email protected]>
Cc: Matt Fleming <[email protected]>
Signed-off-by: Ard Biesheuvel <[email protected]>
---
MAINTAINERS | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/MAINTAINERS b/MAINTAINERS
index 6847ba844ef9..1f38999d8ce7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4625,12 +4625,14 @@ L: [email protected]
T: git git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi.git
S: Maintained
F: Documentation/efi-stub.txt
-F: arch/ia64/kernel/efi.c
+F: arch/*/kernel/efi.c
F: arch/x86/boot/compressed/eboot.[ch]
-F: arch/x86/include/asm/efi.h
+F: arch/*/include/asm/efi.h
F: arch/x86/platform/efi/
F: drivers/firmware/efi/
F: include/linux/efi*.h
+F: arch/arm/boot/compressed/efi-header.S
+F: arch/arm64/kernel/efi-entry.S

EFI VARIABLE FILESYSTEM
M: Matthew Garrett <[email protected]>
--
2.10.0

2016-11-12 21:34:39

by Matt Fleming

[permalink] [raw]
Subject: [PATCH 1/9] efi/libstub: Fix allocation size calculations

From: Roy Franz <[email protected]>

Adjust the size used in calculations to match the actual size of allocation
that will be performed based on EFI size/alignment constraints.
efi_high_alloc() and efi_low_alloc() use the passed size in bytes directly
to find space in the memory map for the allocation, rather than the actual
allocation size that has been adjusted for size and alignment constraints.
This results in failed allocations and retries in efi_high_alloc(). The
same error is present in efi_low_alloc(), although failure will only happen
if the lowest memory block is small.
Also use EFI_PAGE_SIZE consistently and remove use of EFI_PAGE_SHIFT to
calculate page size.

Signed-off-by: Roy Franz <[email protected]>
Signed-off-by: Ard Biesheuvel <[email protected]>
Cc: Matt Fleming <[email protected]>
---
drivers/firmware/efi/libstub/efi-stub-helper.c | 24 ++++++++++++++----------
1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index aded10662020..4b74bf86c74d 100644
--- a/drivers/firmware/efi/libstub/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
@@ -186,14 +186,16 @@ efi_status_t efi_high_alloc(efi_system_table_t *sys_table_arg,
goto fail;

/*
- * Enforce minimum alignment that EFI requires when requesting
- * a specific address. We are doing page-based allocations,
- * so we must be aligned to a page.
+ * Enforce minimum alignment that EFI or Linux requires when
+ * requesting a specific address. We are doing page-based (or
+ * larger) allocations, and both the address and size must meet
+ * alignment constraints.
*/
if (align < EFI_ALLOC_ALIGN)
align = EFI_ALLOC_ALIGN;

- nr_pages = round_up(size, EFI_ALLOC_ALIGN) / EFI_PAGE_SIZE;
+ size = round_up(size, EFI_ALLOC_ALIGN);
+ nr_pages = size / EFI_PAGE_SIZE;
again:
for (i = 0; i < map_size / desc_size; i++) {
efi_memory_desc_t *desc;
@@ -208,7 +210,7 @@ efi_status_t efi_high_alloc(efi_system_table_t *sys_table_arg,
continue;

start = desc->phys_addr;
- end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
+ end = start + desc->num_pages * EFI_PAGE_SIZE;

if (end > max)
end = max;
@@ -278,14 +280,16 @@ efi_status_t efi_low_alloc(efi_system_table_t *sys_table_arg,
goto fail;

/*
- * Enforce minimum alignment that EFI requires when requesting
- * a specific address. We are doing page-based allocations,
- * so we must be aligned to a page.
+ * Enforce minimum alignment that EFI or Linux requires when
+ * requesting a specific address. We are doing page-based (or
+ * larger) allocations, and both the address and size must meet
+ * alignment constraints.
*/
if (align < EFI_ALLOC_ALIGN)
align = EFI_ALLOC_ALIGN;

- nr_pages = round_up(size, EFI_ALLOC_ALIGN) / EFI_PAGE_SIZE;
+ size = round_up(size, EFI_ALLOC_ALIGN);
+ nr_pages = size / EFI_PAGE_SIZE;
for (i = 0; i < map_size / desc_size; i++) {
efi_memory_desc_t *desc;
unsigned long m = (unsigned long)map;
@@ -300,7 +304,7 @@ efi_status_t efi_low_alloc(efi_system_table_t *sys_table_arg,
continue;

start = desc->phys_addr;
- end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
+ end = start + desc->num_pages * EFI_PAGE_SIZE;

/*
* Don't allocate at 0x0. It will confuse code that
--
2.10.0

2016-11-13 07:19:45

by Ingo Molnar

[permalink] [raw]
Subject: Re: [PATCH 5/9] efi/arm*: libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table


* Matt Fleming <[email protected]> wrote:

> From: Ard Biesheuvel <[email protected]>
>
> Invoke the EFI_RNG_PROTOCOL protocol in the context of the stub and
> install the Linux-specific RNG seed UEFI config table. This will be
> picked up by the EFI routines in the core kernel to seed the kernel
> entropy pool.
>
> Cc: Matt Fleming <[email protected]>
> Reviewed-by: Kees Cook <[email protected]>
> Signed-off-by: Ard Biesheuvel <[email protected]>

This commit (and the commits after this one) doesn't have a proper signoff chain,
probably due to rebasing?

I'll apply the patches from email and add your SOB.

Thanks,

Ingo

2016-11-13 08:59:41

by Ingo Molnar

[permalink] [raw]
Subject: Re: [PATCH 5/9] efi/arm*: libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table


* Ingo Molnar <[email protected]> wrote:

> I'll apply the patches from email and add your SOB.

Note that the attached config produces this build error:

drivers/firmware/efi/apple-properties.c:149:9: error: implicit declaration of function ‘efi_get_device_by_path’ [-Werror=implicit-function-declaration]

also:

warning: (THUNDERBOLT) selects APPLE_PROPERTIES which has unmet direct dependencies (EFI && EFI_STUB && X86)

Thanks,

Ingo


Attachments:
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Subject: [tip:efi/core] efi/libstub: Fix allocation size calculations

Commit-ID: 5b88a31c222c47cb8997021cc8a576927ba0e77f
Gitweb: http://git.kernel.org/tip/5b88a31c222c47cb8997021cc8a576927ba0e77f
Author: Roy Franz <[email protected]>
AuthorDate: Sat, 12 Nov 2016 21:32:29 +0000
Committer: Ingo Molnar <[email protected]>
CommitDate: Sun, 13 Nov 2016 08:23:14 +0100

efi/libstub: Fix allocation size calculations

Adjust the size used in calculations to match the actual size of allocation
that will be performed based on EFI size/alignment constraints.
efi_high_alloc() and efi_low_alloc() use the passed size in bytes directly
to find space in the memory map for the allocation, rather than the actual
allocation size that has been adjusted for size and alignment constraints.
This results in failed allocations and retries in efi_high_alloc(). The
same error is present in efi_low_alloc(), although failure will only happen
if the lowest memory block is small.
Also use EFI_PAGE_SIZE consistently and remove use of EFI_PAGE_SHIFT to
calculate page size.

Signed-off-by: Roy Franz <[email protected]>
Signed-off-by: Ard Biesheuvel <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
drivers/firmware/efi/libstub/efi-stub-helper.c | 24 ++++++++++++++----------
1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index aded106..4b74bf8 100644
--- a/drivers/firmware/efi/libstub/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
@@ -186,14 +186,16 @@ efi_status_t efi_high_alloc(efi_system_table_t *sys_table_arg,
goto fail;

/*
- * Enforce minimum alignment that EFI requires when requesting
- * a specific address. We are doing page-based allocations,
- * so we must be aligned to a page.
+ * Enforce minimum alignment that EFI or Linux requires when
+ * requesting a specific address. We are doing page-based (or
+ * larger) allocations, and both the address and size must meet
+ * alignment constraints.
*/
if (align < EFI_ALLOC_ALIGN)
align = EFI_ALLOC_ALIGN;

- nr_pages = round_up(size, EFI_ALLOC_ALIGN) / EFI_PAGE_SIZE;
+ size = round_up(size, EFI_ALLOC_ALIGN);
+ nr_pages = size / EFI_PAGE_SIZE;
again:
for (i = 0; i < map_size / desc_size; i++) {
efi_memory_desc_t *desc;
@@ -208,7 +210,7 @@ again:
continue;

start = desc->phys_addr;
- end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
+ end = start + desc->num_pages * EFI_PAGE_SIZE;

if (end > max)
end = max;
@@ -278,14 +280,16 @@ efi_status_t efi_low_alloc(efi_system_table_t *sys_table_arg,
goto fail;

/*
- * Enforce minimum alignment that EFI requires when requesting
- * a specific address. We are doing page-based allocations,
- * so we must be aligned to a page.
+ * Enforce minimum alignment that EFI or Linux requires when
+ * requesting a specific address. We are doing page-based (or
+ * larger) allocations, and both the address and size must meet
+ * alignment constraints.
*/
if (align < EFI_ALLOC_ALIGN)
align = EFI_ALLOC_ALIGN;

- nr_pages = round_up(size, EFI_ALLOC_ALIGN) / EFI_PAGE_SIZE;
+ size = round_up(size, EFI_ALLOC_ALIGN);
+ nr_pages = size / EFI_PAGE_SIZE;
for (i = 0; i < map_size / desc_size; i++) {
efi_memory_desc_t *desc;
unsigned long m = (unsigned long)map;
@@ -300,7 +304,7 @@ efi_status_t efi_low_alloc(efi_system_table_t *sys_table_arg,
continue;

start = desc->phys_addr;
- end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
+ end = start + desc->num_pages * EFI_PAGE_SIZE;

/*
* Don't allocate at 0x0. It will confuse code that

Subject: [tip:efi/core] efi: Add support for seeding the RNG from a UEFI config table

Commit-ID: 636259880a7e7d3446a707dddebc799da94bdd0b
Gitweb: http://git.kernel.org/tip/636259880a7e7d3446a707dddebc799da94bdd0b
Author: Ard Biesheuvel <[email protected]>
AuthorDate: Sat, 12 Nov 2016 21:32:31 +0000
Committer: Ingo Molnar <[email protected]>
CommitDate: Sun, 13 Nov 2016 08:23:14 +0100

efi: Add support for seeding the RNG from a UEFI config table

Specify a Linux specific UEFI configuration table that carries some
random bits, and use the contents during early boot to seed the kernel's
random number generator. This allows much strong random numbers to be
generated early on.

The entropy is fed to the kernel using add_device_randomness(), which is
documented as being appropriate for being called very early.

Since UEFI configuration tables may also be consumed by kexec'd kernels,
register a reboot notifier that updates the seed in the table.

Note that the config table could be generated by the EFI stub or by any
other UEFI driver or application (e.g., GRUB), but the random seed table
GUID and the associated functionality should be considered an internal
kernel interface (unless it is promoted to ABI later on)

Signed-off-by: Ard Biesheuvel <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
drivers/firmware/efi/efi.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++
include/linux/efi.h | 8 ++++++
2 files changed, 80 insertions(+)

diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index a4944e2..9291480 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -23,7 +23,10 @@
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/io.h>
+#include <linux/kexec.h>
#include <linux/platform_device.h>
+#include <linux/random.h>
+#include <linux/reboot.h>
#include <linux/slab.h>
#include <linux/acpi.h>
#include <linux/ucs2_string.h>
@@ -48,6 +51,7 @@ struct efi __read_mostly efi = {
.esrt = EFI_INVALID_TABLE_ADDR,
.properties_table = EFI_INVALID_TABLE_ADDR,
.mem_attr_table = EFI_INVALID_TABLE_ADDR,
+ .rng_seed = EFI_INVALID_TABLE_ADDR,
};
EXPORT_SYMBOL(efi);

@@ -440,6 +444,7 @@ static __initdata efi_config_table_type_t common_tables[] = {
{EFI_SYSTEM_RESOURCE_TABLE_GUID, "ESRT", &efi.esrt},
{EFI_PROPERTIES_TABLE_GUID, "PROP", &efi.properties_table},
{EFI_MEMORY_ATTRIBUTES_TABLE_GUID, "MEMATTR", &efi.mem_attr_table},
+ {LINUX_EFI_RANDOM_SEED_TABLE_GUID, "RNG", &efi.rng_seed},
{NULL_GUID, NULL, NULL},
};

@@ -501,6 +506,29 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz,
pr_cont("\n");
set_bit(EFI_CONFIG_TABLES, &efi.flags);

+ if (efi.rng_seed != EFI_INVALID_TABLE_ADDR) {
+ struct linux_efi_random_seed *seed;
+ u32 size = 0;
+
+ seed = early_memremap(efi.rng_seed, sizeof(*seed));
+ if (seed != NULL) {
+ size = seed->size;
+ early_memunmap(seed, sizeof(*seed));
+ } else {
+ pr_err("Could not map UEFI random seed!\n");
+ }
+ if (size > 0) {
+ seed = early_memremap(efi.rng_seed,
+ sizeof(*seed) + size);
+ if (seed != NULL) {
+ add_device_randomness(seed->bits, seed->size);
+ early_memunmap(seed, sizeof(*seed) + size);
+ } else {
+ pr_err("Could not map UEFI random seed!\n");
+ }
+ }
+ }
+
/* Parse the EFI Properties table if it exists */
if (efi.properties_table != EFI_INVALID_TABLE_ADDR) {
efi_properties_table_t *tbl;
@@ -824,3 +852,47 @@ int efi_status_to_err(efi_status_t status)

return err;
}
+
+#ifdef CONFIG_KEXEC
+static int update_efi_random_seed(struct notifier_block *nb,
+ unsigned long code, void *unused)
+{
+ struct linux_efi_random_seed *seed;
+ u32 size = 0;
+
+ if (!kexec_in_progress)
+ return NOTIFY_DONE;
+
+ seed = memremap(efi.rng_seed, sizeof(*seed), MEMREMAP_WB);
+ if (seed != NULL) {
+ size = min(seed->size, 32U);
+ memunmap(seed);
+ } else {
+ pr_err("Could not map UEFI random seed!\n");
+ }
+ if (size > 0) {
+ seed = memremap(efi.rng_seed, sizeof(*seed) + size,
+ MEMREMAP_WB);
+ if (seed != NULL) {
+ seed->size = size;
+ get_random_bytes(seed->bits, seed->size);
+ memunmap(seed);
+ } else {
+ pr_err("Could not map UEFI random seed!\n");
+ }
+ }
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block efi_random_seed_nb = {
+ .notifier_call = update_efi_random_seed,
+};
+
+static int register_update_efi_random_seed(void)
+{
+ if (efi.rng_seed == EFI_INVALID_TABLE_ADDR)
+ return 0;
+ return register_reboot_notifier(&efi_random_seed_nb);
+}
+late_initcall(register_update_efi_random_seed);
+#endif
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 2d08948..85e28b1 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -599,6 +599,7 @@ void efi_native_runtime_setup(void);
*/
#define LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID EFI_GUID(0xe03fc20a, 0x85dc, 0x406e, 0xb9, 0x0e, 0x4a, 0xb5, 0x02, 0x37, 0x1d, 0x95)
#define LINUX_EFI_LOADER_ENTRY_GUID EFI_GUID(0x4a67b082, 0x0a4c, 0x41cf, 0xb6, 0xc7, 0x44, 0x0b, 0x29, 0xbb, 0x8c, 0x4f)
+#define LINUX_EFI_RANDOM_SEED_TABLE_GUID EFI_GUID(0x1ce1e5bc, 0x7ceb, 0x42f2, 0x81, 0xe5, 0x8a, 0xad, 0xf1, 0x80, 0xf5, 0x7b)

typedef struct {
efi_guid_t guid;
@@ -872,6 +873,7 @@ extern struct efi {
unsigned long esrt; /* ESRT table */
unsigned long properties_table; /* properties table */
unsigned long mem_attr_table; /* memory attributes table */
+ unsigned long rng_seed; /* UEFI firmware random seed */
efi_get_time_t *get_time;
efi_set_time_t *set_time;
efi_get_wakeup_time_t *get_wakeup_time;
@@ -1493,4 +1495,10 @@ efi_status_t efi_exit_boot_services(efi_system_table_t *sys_table,
struct efi_boot_memmap *map,
void *priv,
efi_exit_boot_map_processing priv_func);
+
+struct linux_efi_random_seed {
+ u32 size;
+ u8 bits[];
+};
+
#endif /* _LINUX_EFI_H */

Subject: [tip:efi/core] efi/libstub: Add random.c to ARM build

Commit-ID: a6a144698db93a2c456d1e3811140cadef1ba0e3
Gitweb: http://git.kernel.org/tip/a6a144698db93a2c456d1e3811140cadef1ba0e3
Author: Ard Biesheuvel <[email protected]>
AuthorDate: Sat, 12 Nov 2016 21:32:32 +0000
Committer: Ingo Molnar <[email protected]>
CommitDate: Sun, 13 Nov 2016 08:23:15 +0100

efi/libstub: Add random.c to ARM build

Make random.c build for ARM by moving the fallback definition of
EFI_ALLOC_ALIGN to efistub.h, and replacing a division by a value
we know to be a power of 2 with a right shift (this is required since
ARM does not have any integer division helper routines in its decompressor)

Signed-off-by: Ard Biesheuvel <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
drivers/firmware/efi/libstub/Makefile | 4 ++--
drivers/firmware/efi/libstub/efi-stub-helper.c | 9 ---------
drivers/firmware/efi/libstub/efistub.h | 9 +++++++++
drivers/firmware/efi/libstub/random.c | 8 +++++---
4 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index 5e23e2d..6621b13 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -36,11 +36,11 @@ arm-deps := fdt_rw.c fdt_ro.c fdt_wip.c fdt.c fdt_empty_tree.c fdt_sw.c sort.c
$(obj)/lib-%.o: $(srctree)/lib/%.c FORCE
$(call if_changed_rule,cc_o_c)

-lib-$(CONFIG_EFI_ARMSTUB) += arm-stub.o fdt.o string.o \
+lib-$(CONFIG_EFI_ARMSTUB) += arm-stub.o fdt.o string.o random.o \
$(patsubst %.c,lib-%.o,$(arm-deps))

lib-$(CONFIG_ARM) += arm32-stub.o
-lib-$(CONFIG_ARM64) += arm64-stub.o random.o
+lib-$(CONFIG_ARM64) += arm64-stub.o
CFLAGS_arm64-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET)

#
diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index 4b74bf8..757badc 100644
--- a/drivers/firmware/efi/libstub/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
@@ -32,15 +32,6 @@

static unsigned long __chunk_size = EFI_READ_CHUNK_SIZE;

-/*
- * Allow the platform to override the allocation granularity: this allows
- * systems that have the capability to run with a larger page size to deal
- * with the allocations for initrd and fdt more efficiently.
- */
-#ifndef EFI_ALLOC_ALIGN
-#define EFI_ALLOC_ALIGN EFI_PAGE_SIZE
-#endif
-
#define EFI_MMAP_NR_SLACK_SLOTS 8

struct file_info {
diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index ee49cd2..fe1f225 100644
--- a/drivers/firmware/efi/libstub/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -15,6 +15,15 @@
*/
#undef __init

+/*
+ * Allow the platform to override the allocation granularity: this allows
+ * systems that have the capability to run with a larger page size to deal
+ * with the allocations for initrd and fdt more efficiently.
+ */
+#ifndef EFI_ALLOC_ALIGN
+#define EFI_ALLOC_ALIGN EFI_PAGE_SIZE
+#endif
+
void efi_char16_printk(efi_system_table_t *, efi_char16_t *);

efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg, void *__image,
diff --git a/drivers/firmware/efi/libstub/random.c b/drivers/firmware/efi/libstub/random.c
index 0c9f58c..f8e2e5a 100644
--- a/drivers/firmware/efi/libstub/random.c
+++ b/drivers/firmware/efi/libstub/random.c
@@ -8,6 +8,7 @@
*/

#include <linux/efi.h>
+#include <linux/log2.h>
#include <asm/efi.h>

#include "efistub.h"
@@ -41,8 +42,9 @@ efi_status_t efi_get_random_bytes(efi_system_table_t *sys_table_arg,
*/
static unsigned long get_entry_num_slots(efi_memory_desc_t *md,
unsigned long size,
- unsigned long align)
+ unsigned long align_shift)
{
+ unsigned long align = 1UL << align_shift;
u64 start, end;

if (md->type != EFI_CONVENTIONAL_MEMORY)
@@ -55,7 +57,7 @@ static unsigned long get_entry_num_slots(efi_memory_desc_t *md,
if (start > end)
return 0;

- return (end - start + 1) / align;
+ return (end - start + 1) >> align_shift;
}

/*
@@ -98,7 +100,7 @@ efi_status_t efi_random_alloc(efi_system_table_t *sys_table_arg,
efi_memory_desc_t *md = (void *)memory_map + map_offset;
unsigned long slots;

- slots = get_entry_num_slots(md, size, align);
+ slots = get_entry_num_slots(md, size, ilog2(align));
MD_NUM_SLOTS(md) = slots;
total_slots += slots;
}

Subject: [tip:efi/core] MAINTAINERS: Add ARM and arm64 EFI specific files to EFI subsystem

Commit-ID: f135a176426fc643caf6480e3200f1733f58dbf6
Gitweb: http://git.kernel.org/tip/f135a176426fc643caf6480e3200f1733f58dbf6
Author: Ard Biesheuvel <[email protected]>
AuthorDate: Sat, 12 Nov 2016 21:32:30 +0000
Committer: Ingo Molnar <[email protected]>
CommitDate: Sun, 13 Nov 2016 08:23:14 +0100

MAINTAINERS: Add ARM and arm64 EFI specific files to EFI subsystem

Since I will be co-maintaining the EFI subsystem, it makes sense to
mention the ARM and arm64 EFI bits in the EFI section in MAINTAINERS
so that Matt, the list and I get cc'ed on proposed changes.

Signed-off-by: Ard Biesheuvel <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
Acked-by: Will Deacon <[email protected]>
Acked-by: Russell King <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: M: Matthew Garrett <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
MAINTAINERS | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/MAINTAINERS b/MAINTAINERS
index 851b89b..afaf24f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4631,12 +4631,14 @@ L: [email protected]
T: git git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi.git
S: Maintained
F: Documentation/efi-stub.txt
-F: arch/ia64/kernel/efi.c
+F: arch/*/kernel/efi.c
F: arch/x86/boot/compressed/eboot.[ch]
-F: arch/x86/include/asm/efi.h
+F: arch/*/include/asm/efi.h
F: arch/x86/platform/efi/
F: drivers/firmware/efi/
F: include/linux/efi*.h
+F: arch/arm/boot/compressed/efi-header.S
+F: arch/arm64/kernel/efi-entry.S

EFI VARIABLE FILESYSTEM
M: Matthew Garrett <[email protected]>

Subject: [tip:efi/core] efi/arm*/libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table

Commit-ID: 568bc4e87033d232c5fd00d5b0cd22a2ccc04944
Gitweb: http://git.kernel.org/tip/568bc4e87033d232c5fd00d5b0cd22a2ccc04944
Author: Ard Biesheuvel <[email protected]>
AuthorDate: Sat, 12 Nov 2016 21:32:33 +0000
Committer: Ingo Molnar <[email protected]>
CommitDate: Sun, 13 Nov 2016 08:23:15 +0100

efi/arm*/libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table

Invoke the EFI_RNG_PROTOCOL protocol in the context of the stub and
install the Linux-specific RNG seed UEFI config table. This will be
picked up by the EFI routines in the core kernel to seed the kernel
entropy pool.

Signed-off-by: Ard Biesheuvel <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
drivers/firmware/efi/libstub/arm-stub.c | 2 ++
drivers/firmware/efi/libstub/efistub.h | 2 ++
drivers/firmware/efi/libstub/random.c | 48 +++++++++++++++++++++++++++++++++
include/linux/efi.h | 1 +
4 files changed, 53 insertions(+)

diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c
index 993aa56..b4f7d78 100644
--- a/drivers/firmware/efi/libstub/arm-stub.c
+++ b/drivers/firmware/efi/libstub/arm-stub.c
@@ -340,6 +340,8 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table,
if (status != EFI_SUCCESS)
pr_efi_err(sys_table, "Failed initrd from command line!\n");

+ efi_random_get_seed(sys_table);
+
new_fdt_addr = fdt_addr;
status = allocate_new_fdt_and_exit_boot(sys_table, handle,
&new_fdt_addr, dram_base + MAX_FDT_OFFSET,
diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index fe1f225..b98824e 100644
--- a/drivers/firmware/efi/libstub/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -71,4 +71,6 @@ efi_status_t efi_random_alloc(efi_system_table_t *sys_table_arg,

efi_status_t check_platform_features(efi_system_table_t *sys_table_arg);

+efi_status_t efi_random_get_seed(efi_system_table_t *sys_table_arg);
+
#endif
diff --git a/drivers/firmware/efi/libstub/random.c b/drivers/firmware/efi/libstub/random.c
index f8e2e5a..3a3feac 100644
--- a/drivers/firmware/efi/libstub/random.c
+++ b/drivers/firmware/efi/libstub/random.c
@@ -143,3 +143,51 @@ efi_status_t efi_random_alloc(efi_system_table_t *sys_table_arg,

return status;
}
+
+#define RANDOM_SEED_SIZE 32
+
+efi_status_t efi_random_get_seed(efi_system_table_t *sys_table_arg)
+{
+ efi_guid_t rng_proto = EFI_RNG_PROTOCOL_GUID;
+ efi_guid_t rng_algo_raw = EFI_RNG_ALGORITHM_RAW;
+ efi_guid_t rng_table_guid = LINUX_EFI_RANDOM_SEED_TABLE_GUID;
+ struct efi_rng_protocol *rng;
+ struct linux_efi_random_seed *seed;
+ efi_status_t status;
+
+ status = efi_call_early(locate_protocol, &rng_proto, NULL,
+ (void **)&rng);
+ if (status != EFI_SUCCESS)
+ return status;
+
+ status = efi_call_early(allocate_pool, EFI_RUNTIME_SERVICES_DATA,
+ sizeof(*seed) + RANDOM_SEED_SIZE,
+ (void **)&seed);
+ if (status != EFI_SUCCESS)
+ return status;
+
+ status = rng->get_rng(rng, &rng_algo_raw, RANDOM_SEED_SIZE,
+ seed->bits);
+ if (status == EFI_UNSUPPORTED)
+ /*
+ * Use whatever algorithm we have available if the raw algorithm
+ * is not implemented.
+ */
+ status = rng->get_rng(rng, NULL, RANDOM_SEED_SIZE,
+ seed->bits);
+
+ if (status != EFI_SUCCESS)
+ goto err_freepool;
+
+ seed->size = RANDOM_SEED_SIZE;
+ status = efi_call_early(install_configuration_table, &rng_table_guid,
+ seed);
+ if (status != EFI_SUCCESS)
+ goto err_freepool;
+
+ return EFI_SUCCESS;
+
+err_freepool:
+ efi_call_early(free_pool, seed);
+ return status;
+}
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 85e28b1..f5a821d 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -589,6 +589,7 @@ void efi_native_runtime_setup(void);
#define DEVICE_TREE_GUID EFI_GUID(0xb1b621d5, 0xf19c, 0x41a5, 0x83, 0x0b, 0xd9, 0x15, 0x2c, 0x69, 0xaa, 0xe0)
#define EFI_PROPERTIES_TABLE_GUID EFI_GUID(0x880aaca3, 0x4adc, 0x4a04, 0x90, 0x79, 0xb7, 0x47, 0x34, 0x08, 0x25, 0xe5)
#define EFI_RNG_PROTOCOL_GUID EFI_GUID(0x3152bca5, 0xeade, 0x433d, 0x86, 0x2e, 0xc0, 0x1c, 0xdc, 0x29, 0x1f, 0x44)
+#define EFI_RNG_ALGORITHM_RAW EFI_GUID(0xe43176d7, 0xb6e8, 0x4827, 0xb7, 0x84, 0x7f, 0xfd, 0xc4, 0xb6, 0x85, 0x61)
#define EFI_MEMORY_ATTRIBUTES_TABLE_GUID EFI_GUID(0xdcfa911d, 0x26eb, 0x469f, 0xa2, 0x20, 0x38, 0xb7, 0xdc, 0x46, 0x12, 0x20)
#define EFI_CONSOLE_OUT_DEVICE_GUID EFI_GUID(0xd3b36f2c, 0xd551, 0x11d4, 0x9a, 0x46, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d)


Subject: [tip:efi/core] efi: Add device path parser

Commit-ID: 46cd4b75cd0edee76e0096225c2d31f8d90e92a2
Gitweb: http://git.kernel.org/tip/46cd4b75cd0edee76e0096225c2d31f8d90e92a2
Author: Lukas Wunner <[email protected]>
AuthorDate: Sat, 12 Nov 2016 21:32:34 +0000
Committer: Ingo Molnar <[email protected]>
CommitDate: Sun, 13 Nov 2016 08:23:15 +0100

efi: Add device path parser

We're about to extended the efistub to retrieve device properties from
EFI on Apple Macs. The properties use EFI Device Paths to indicate the
device they belong to. This commit adds a parser which, given an EFI
Device Path, locates the corresponding struct device and returns a
reference to it.

Initially only ACPI and PCI Device Path nodes are supported, these are
the only types needed for Apple device properties (the corresponding
macOS function AppleACPIPlatformExpert::matchEFIDevicePath() does not
support any others). Further node types can be added with little to
moderate effort.

Apple device properties is currently the only use case of this parser,
but Peter Jones intends to use it to match up devices with the
ConInDev/ConOutDev/ErrOutDev variables and add sysfs attributes to these
devices to say the hardware supports using them as console. Thus,
make this parser a separate component which can be selected with config
option EFI_DEV_PATH_PARSER. It can in principle be compiled as a module
if acpi_get_first_physical_node() and acpi_bus_type are exported (and
efi_get_device_by_path() itself is exported).

The dependency on CONFIG_ACPI is needed for acpi_match_device_ids().
It can be removed if an empty inline stub is added for that function.

Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
Cc: Andreas Noever <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Jones <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
drivers/firmware/efi/Kconfig | 5 +
drivers/firmware/efi/Makefile | 1 +
drivers/firmware/efi/dev-path-parser.c | 203 +++++++++++++++++++++++++++++++++
include/linux/efi.h | 20 ++++
4 files changed, 229 insertions(+)

diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index c981be1..893fda4 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -133,3 +133,8 @@ endmenu

config UEFI_CPER
bool
+
+config EFI_DEV_PATH_PARSER
+ bool
+ depends on ACPI
+ default n
diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile
index c8a439f..3e91ae3 100644
--- a/drivers/firmware/efi/Makefile
+++ b/drivers/firmware/efi/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_EFI_STUB) += libstub/
obj-$(CONFIG_EFI_FAKE_MEMMAP) += fake_mem.o
obj-$(CONFIG_EFI_BOOTLOADER_CONTROL) += efibc.o
obj-$(CONFIG_EFI_TEST) += test/
+obj-$(CONFIG_EFI_DEV_PATH_PARSER) += dev-path-parser.o

arm-obj-$(CONFIG_EFI) := arm-init.o arm-runtime.o
obj-$(CONFIG_ARM) += $(arm-obj-y)
diff --git a/drivers/firmware/efi/dev-path-parser.c b/drivers/firmware/efi/dev-path-parser.c
new file mode 100644
index 0000000..85d1834
--- /dev/null
+++ b/drivers/firmware/efi/dev-path-parser.c
@@ -0,0 +1,203 @@
+/*
+ * dev-path-parser.c - EFI Device Path parser
+ * Copyright (C) 2016 Lukas Wunner <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2) as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/acpi.h>
+#include <linux/efi.h>
+#include <linux/pci.h>
+
+struct acpi_hid_uid {
+ struct acpi_device_id hid[2];
+ char uid[11]; /* UINT_MAX + null byte */
+};
+
+static int __init match_acpi_dev(struct device *dev, void *data)
+{
+ struct acpi_hid_uid hid_uid = *(struct acpi_hid_uid *)data;
+ struct acpi_device *adev = to_acpi_device(dev);
+
+ if (acpi_match_device_ids(adev, hid_uid.hid))
+ return 0;
+
+ if (adev->pnp.unique_id)
+ return !strcmp(adev->pnp.unique_id, hid_uid.uid);
+ else
+ return !strcmp("0", hid_uid.uid);
+}
+
+static long __init parse_acpi_path(struct efi_dev_path *node,
+ struct device *parent, struct device **child)
+{
+ struct acpi_hid_uid hid_uid = {};
+ struct device *phys_dev;
+
+ if (node->length != 12)
+ return -EINVAL;
+
+ sprintf(hid_uid.hid[0].id, "%c%c%c%04X",
+ 'A' + ((node->acpi.hid >> 10) & 0x1f) - 1,
+ 'A' + ((node->acpi.hid >> 5) & 0x1f) - 1,
+ 'A' + ((node->acpi.hid >> 0) & 0x1f) - 1,
+ node->acpi.hid >> 16);
+ sprintf(hid_uid.uid, "%u", node->acpi.uid);
+
+ *child = bus_find_device(&acpi_bus_type, NULL, &hid_uid,
+ match_acpi_dev);
+ if (!*child)
+ return -ENODEV;
+
+ phys_dev = acpi_get_first_physical_node(to_acpi_device(*child));
+ if (phys_dev) {
+ get_device(phys_dev);
+ put_device(*child);
+ *child = phys_dev;
+ }
+
+ return 0;
+}
+
+static int __init match_pci_dev(struct device *dev, void *data)
+{
+ unsigned int devfn = *(unsigned int *)data;
+
+ return dev_is_pci(dev) && to_pci_dev(dev)->devfn == devfn;
+}
+
+static long __init parse_pci_path(struct efi_dev_path *node,
+ struct device *parent, struct device **child)
+{
+ unsigned int devfn;
+
+ if (node->length != 6)
+ return -EINVAL;
+ if (!parent)
+ return -EINVAL;
+
+ devfn = PCI_DEVFN(node->pci.dev, node->pci.fn);
+
+ *child = device_find_child(parent, &devfn, match_pci_dev);
+ if (!*child)
+ return -ENODEV;
+
+ return 0;
+}
+
+/*
+ * Insert parsers for further node types here.
+ *
+ * Each parser takes a pointer to the @node and to the @parent (will be NULL
+ * for the first device path node). If a device corresponding to @node was
+ * found below @parent, its reference count should be incremented and the
+ * device returned in @child.
+ *
+ * The return value should be 0 on success or a negative int on failure.
+ * The special return values 0x01 (EFI_DEV_END_INSTANCE) and 0xFF
+ * (EFI_DEV_END_ENTIRE) signal the end of the device path, only
+ * parse_end_path() is supposed to return this.
+ *
+ * Be sure to validate the node length and contents before commencing the
+ * search for a device.
+ */
+
+static long __init parse_end_path(struct efi_dev_path *node,
+ struct device *parent, struct device **child)
+{
+ if (node->length != 4)
+ return -EINVAL;
+ if (node->sub_type != EFI_DEV_END_INSTANCE &&
+ node->sub_type != EFI_DEV_END_ENTIRE)
+ return -EINVAL;
+ if (!parent)
+ return -ENODEV;
+
+ *child = get_device(parent);
+ return node->sub_type;
+}
+
+/**
+ * efi_get_device_by_path - find device by EFI Device Path
+ * @node: EFI Device Path
+ * @len: maximum length of EFI Device Path in bytes
+ *
+ * Parse a series of EFI Device Path nodes at @node and find the corresponding
+ * device. If the device was found, its reference count is incremented and a
+ * pointer to it is returned. The caller needs to drop the reference with
+ * put_device() after use. The @node pointer is updated to point to the
+ * location immediately after the "End of Hardware Device Path" node.
+ *
+ * If another Device Path instance follows, @len is decremented by the number
+ * of bytes consumed. Otherwise @len is set to %0.
+ *
+ * If a Device Path node is malformed or its corresponding device is not found,
+ * @node is updated to point to this offending node and an ERR_PTR is returned.
+ *
+ * If @len is initially %0, the function returns %NULL. Thus, to iterate over
+ * all instances in a path, the following idiom may be used:
+ *
+ * while (!IS_ERR_OR_NULL(dev = efi_get_device_by_path(&node, &len))) {
+ * // do something with dev
+ * put_device(dev);
+ * }
+ * if (IS_ERR(dev))
+ * // report error
+ *
+ * Devices can only be found if they're already instantiated. Most buses
+ * instantiate devices in the "subsys" initcall level, hence the earliest
+ * initcall level in which this function should be called is "fs".
+ *
+ * Returns the device on success or
+ * %ERR_PTR(-ENODEV) if no device was found,
+ * %ERR_PTR(-EINVAL) if a node is malformed or exceeds @len,
+ * %ERR_PTR(-ENOTSUPP) if support for a node type is not yet implemented.
+ */
+struct device * __init efi_get_device_by_path(struct efi_dev_path **node,
+ size_t *len)
+{
+ struct device *parent = NULL, *child;
+ long ret = 0;
+
+ if (!*len)
+ return NULL;
+
+ while (!ret) {
+ if (*len < 4 || *len < (*node)->length)
+ ret = -EINVAL;
+ else if ((*node)->type == EFI_DEV_ACPI &&
+ (*node)->sub_type == EFI_DEV_BASIC_ACPI)
+ ret = parse_acpi_path(*node, parent, &child);
+ else if ((*node)->type == EFI_DEV_HW &&
+ (*node)->sub_type == EFI_DEV_PCI)
+ ret = parse_pci_path(*node, parent, &child);
+ else if (((*node)->type == EFI_DEV_END_PATH ||
+ (*node)->type == EFI_DEV_END_PATH2))
+ ret = parse_end_path(*node, parent, &child);
+ else
+ ret = -ENOTSUPP;
+
+ put_device(parent);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
+ parent = child;
+ *node = (void *)*node + (*node)->length;
+ *len -= (*node)->length;
+ }
+
+ if (ret == EFI_DEV_END_ENTIRE)
+ *len = 0;
+
+ return child;
+}
diff --git a/include/linux/efi.h b/include/linux/efi.h
index f5a821d..2617672 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -1148,6 +1148,26 @@ struct efi_generic_dev_path {
u16 length;
} __attribute ((packed));

+struct efi_dev_path {
+ u8 type; /* can be replaced with unnamed */
+ u8 sub_type; /* struct efi_generic_dev_path; */
+ u16 length; /* once we've moved to -std=c11 */
+ union {
+ struct {
+ u32 hid;
+ u32 uid;
+ } acpi;
+ struct {
+ u8 fn;
+ u8 dev;
+ } pci;
+ };
+} __attribute ((packed));
+
+#if IS_ENABLED(CONFIG_EFI_DEV_PATH_PARSER)
+struct device *efi_get_device_by_path(struct efi_dev_path **node, size_t *len);
+#endif
+
static inline void memrange_efi_to_native(u64 *addr, u64 *npages)
{
*npages = PFN_UP(*addr + (*npages<<EFI_PAGE_SHIFT)) - PFN_DOWN(*addr);

Subject: [tip:efi/core] efi: Allow bitness-agnostic protocol calls

Commit-ID: 3552fdf29f01e5a889e88202dc55b67aa6766620
Gitweb: http://git.kernel.org/tip/3552fdf29f01e5a889e88202dc55b67aa6766620
Author: Lukas Wunner <[email protected]>
AuthorDate: Sat, 12 Nov 2016 21:32:35 +0000
Committer: Ingo Molnar <[email protected]>
CommitDate: Sun, 13 Nov 2016 08:23:16 +0100

efi: Allow bitness-agnostic protocol calls

We already have a macro to invoke boot services which on x86 adapts
automatically to the bitness of the EFI firmware: efi_call_early().

The macro allows sharing of functions across arches and bitness variants
as long as those functions only call boot services. However in practice
functions in the EFI stub contain a mix of boot services calls and
protocol calls.

Add an efi_call_proto() macro for bitness-agnostic protocol calls to
allow sharing more code across arches as well as deduplicating 32 bit
and 64 bit code paths.

On x86, implement it using a new efi_table_attr() macro for bitness-
agnostic table lookups. Refactor efi_call_early() to make use of the
same macro. (The resulting object code remains identical.)

Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
Cc: Andreas Noever <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Jones <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
arch/arm/include/asm/efi.h | 3 +++
arch/arm64/include/asm/efi.h | 3 +++
arch/x86/include/asm/efi.h | 16 +++++++++++-----
3 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/arch/arm/include/asm/efi.h b/arch/arm/include/asm/efi.h
index 766bf9b..0b06f53 100644
--- a/arch/arm/include/asm/efi.h
+++ b/arch/arm/include/asm/efi.h
@@ -57,6 +57,9 @@ void efi_virtmap_unload(void);
#define __efi_call_early(f, ...) f(__VA_ARGS__)
#define efi_is_64bit() (false)

+#define efi_call_proto(protocol, f, instance, ...) \
+ ((protocol##_t *)instance)->f(instance, ##__VA_ARGS__)
+
struct screen_info *alloc_screen_info(efi_system_table_t *sys_table_arg);
void free_screen_info(efi_system_table_t *sys_table, struct screen_info *si);

diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h
index a9e54aa..771b3f0 100644
--- a/arch/arm64/include/asm/efi.h
+++ b/arch/arm64/include/asm/efi.h
@@ -51,6 +51,9 @@ int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md);
#define __efi_call_early(f, ...) f(__VA_ARGS__)
#define efi_is_64bit() (true)

+#define efi_call_proto(protocol, f, instance, ...) \
+ ((protocol##_t *)instance)->f(instance, ##__VA_ARGS__)
+
#define alloc_screen_info(x...) &screen_info
#define free_screen_info(x...)

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 389d700..e99675b 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -210,12 +210,18 @@ static inline bool efi_is_64bit(void)
return __efi_early()->is64;
}

+#define efi_table_attr(table, attr, instance) \
+ (efi_is_64bit() ? \
+ ((table##_64_t *)(unsigned long)instance)->attr : \
+ ((table##_32_t *)(unsigned long)instance)->attr)
+
+#define efi_call_proto(protocol, f, instance, ...) \
+ __efi_early()->call(efi_table_attr(protocol, f, instance), \
+ instance, ##__VA_ARGS__)
+
#define efi_call_early(f, ...) \
- __efi_early()->call(efi_is_64bit() ? \
- ((efi_boot_services_64_t *)(unsigned long) \
- __efi_early()->boot_services)->f : \
- ((efi_boot_services_32_t *)(unsigned long) \
- __efi_early()->boot_services)->f, __VA_ARGS__)
+ __efi_early()->call(efi_table_attr(efi_boot_services, f, \
+ __efi_early()->boot_services), __VA_ARGS__)

#define __efi_call_early(f, ...) \
__efi_early()->call((unsigned long)f, __VA_ARGS__);

Subject: [tip:efi/core] x86/efi: Retrieve and assign Apple device properties

Commit-ID: 58c5475aba67706b31d9237808d5d3d54074e5ea
Gitweb: http://git.kernel.org/tip/58c5475aba67706b31d9237808d5d3d54074e5ea
Author: Lukas Wunner <[email protected]>
AuthorDate: Sat, 12 Nov 2016 21:32:36 +0000
Committer: Ingo Molnar <[email protected]>
CommitDate: Sun, 13 Nov 2016 08:23:16 +0100

x86/efi: Retrieve and assign Apple device properties

Apple's EFI drivers supply device properties which are needed to support
Macs optimally. They contain vital information which cannot be obtained
any other way (e.g. Thunderbolt Device ROM). They're also used to convey
the current device state so that OS drivers can pick up where EFI
drivers left (e.g. GPU mode setting).

There's an EFI driver dubbed "AAPL,PathProperties" which implements a
per-device key/value store. Other EFI drivers populate it using a custom
protocol. The macOS bootloader /System/Library/CoreServices/boot.efi
retrieves the properties with the same protocol. The kernel extension
AppleACPIPlatform.kext subsequently merges them into the I/O Kit
registry (see ioreg(8)) where they can be queried by other kernel
extensions and user space.

This commit extends the efistub to retrieve the device properties before
ExitBootServices is called. It assigns them to devices in an fs_initcall
so that they can be queried with the API in <linux/property.h>.

Note that the device properties will only be available if the kernel is
booted with the efistub. Distros should adjust their installers to
always use the efistub on Macs. grub with the "linux" directive will not
work unless the functionality of this commit is duplicated in grub.
(The "linuxefi" directive should work but is not included upstream as of
this writing.)

The custom protocol has GUID 91BD12FE-F6C3-44FB-A5B7-5122AB303AE0 and
looks like this:

typedef struct {
unsigned long version; /* 0x10000 */
efi_status_t (*get) (
IN struct apple_properties_protocol *this,
IN struct efi_dev_path *device,
IN efi_char16_t *property_name,
OUT void *buffer,
IN OUT u32 *buffer_len);
/* EFI_SUCCESS, EFI_NOT_FOUND, EFI_BUFFER_TOO_SMALL */
efi_status_t (*set) (
IN struct apple_properties_protocol *this,
IN struct efi_dev_path *device,
IN efi_char16_t *property_name,
IN void *property_value,
IN u32 property_value_len);
/* allocates copies of property name and value */
/* EFI_SUCCESS, EFI_OUT_OF_RESOURCES */
efi_status_t (*del) (
IN struct apple_properties_protocol *this,
IN struct efi_dev_path *device,
IN efi_char16_t *property_name);
/* EFI_SUCCESS, EFI_NOT_FOUND */
efi_status_t (*get_all) (
IN struct apple_properties_protocol *this,
OUT void *buffer,
IN OUT u32 *buffer_len);
/* EFI_SUCCESS, EFI_BUFFER_TOO_SMALL */
} apple_properties_protocol;

Thanks to Pedro Vilaça for this blog post which was helpful in reverse
engineering Apple's EFI drivers and bootloader:
https://reverse.put.as/2016/06/25/apple-efi-firmware-passwords-and-the-scbo-myth/

If someone at Apple is reading this, please note there's a memory leak
in your implementation of the del() function as the property struct is
freed but the name and value allocations are not.

Neither the macOS bootloader nor Apple's EFI drivers check the protocol
version, but we do to avoid breakage if it's ever changed. It's been the
same since at least OS X 10.6 (2009).

The get_all() function conveniently fills a buffer with all properties
in marshalled form which can be passed to the kernel as a setup_data
payload. The number of device properties is dynamic and can change
between a first invocation of get_all() (to determine the buffer size)
and a second invocation (to retrieve the actual buffer), hence the
peculiar loop which does not finish until the buffer size settles.
The macOS bootloader does the same.

The setup_data payload is later on unmarshalled in an fs_initcall. The
idea is that most buses instantiate devices in "subsys" initcall level
and drivers are usually bound to these devices in "device" initcall
level, so we assign the properties in-between, i.e. in "fs" initcall
level.

This assumes that devices to which properties pertain are instantiated
from a "subsys" initcall or earlier. That should always be the case
since on macOS, AppleACPIPlatformExpert::matchEFIDevicePath() only
supports ACPI and PCI nodes and we've fully scanned those buses during
"subsys" initcall level.

The second assumption is that properties are only needed from a "device"
initcall or later. Seems reasonable to me, but should this ever not work
out, an alternative approach would be to store the property sets e.g. in
a btree early during boot. Then whenever device_add() is called, an EFI
Device Path would have to be constructed for the newly added device,
and looked up in the btree. That way, the property set could be assigned
to the device immediately on instantiation. And this would also work for
devices instantiated in a deferred fashion. It seems like this approach
would be more complicated and require more code. That doesn't seem
justified without a specific use case.

For comparison, the strategy on macOS is to assign properties to objects
in the ACPI namespace (AppleACPIPlatformExpert::mergeEFIProperties()).
That approach is definitely wrong as it fails for devices not present in
the namespace: The NHI EFI driver supplies properties for attached
Thunderbolt devices, yet on Macs with Thunderbolt 1 only one device
level behind the host controller is described in the namespace.
Consequently macOS cannot assign properties for chained devices. With
Thunderbolt 2 they started to describe three device levels behind host
controllers in the namespace but this grossly inflates the SSDT and
still fails if the user daisy-chained more than three devices.

We copy the property names and values from the setup_data payload to
swappable virtual memory and afterwards make the payload available to
the page allocator. This is just for the sake of good housekeeping, it
wouldn't occupy a meaningful amount of physical memory (4444 bytes on my
machine). Only the payload is freed, not the setup_data header since
otherwise we'd break the list linkage and we cannot safely update the
predecessor's ->next link because there's no locking for the list.

The payload is currently not passed on to kexec'ed kernels, same for PCI
ROMs retrieved by setup_efi_pci(). This can be added later if there is
demand by amending setup_efi_state(). The payload can then no longer be
made available to the page allocator of course.

Tested-by: Lukas Wunner <[email protected]> [MacBookPro9,1]
Tested-by: Pierre Moreau <[email protected]> [MacBookPro11,3]
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
Cc: Andreas Noever <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Pedro Vilaça <[email protected]>
Cc: Peter Jones <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
Documentation/kernel-parameters.txt | 5 +
arch/x86/boot/compressed/eboot.c | 65 +++++++++
arch/x86/include/uapi/asm/bootparam.h | 1 +
drivers/firmware/efi/Kconfig | 13 ++
drivers/firmware/efi/Makefile | 1 +
drivers/firmware/efi/apple-properties.c | 248 ++++++++++++++++++++++++++++++++
include/linux/efi.h | 17 +++
7 files changed, 350 insertions(+)

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 37babf9..86a31df 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1062,6 +1062,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.

dscc4.setup= [NET]

+ dump_apple_properties [X86]
+ Dump name and content of EFI device properties on
+ x86 Macs. Useful for driver authors to determine
+ what data is available or for reverse-engineering.
+
dyndbg[="val"] [KNL,DYNAMIC_DEBUG]
module.dyndbg[="val"]
Enable debug messages at boot time. See
diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
index cc69e37..ff01c8f 100644
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -537,6 +537,69 @@ free_handle:
efi_call_early(free_pool, pci_handle);
}

+static void retrieve_apple_device_properties(struct boot_params *boot_params)
+{
+ efi_guid_t guid = APPLE_PROPERTIES_PROTOCOL_GUID;
+ struct setup_data *data, *new;
+ efi_status_t status;
+ u32 size = 0;
+ void *p;
+
+ status = efi_call_early(locate_protocol, &guid, NULL, &p);
+ if (status != EFI_SUCCESS)
+ return;
+
+ if (efi_table_attr(apple_properties_protocol, version, p) != 0x10000) {
+ efi_printk(sys_table, "Unsupported properties proto version\n");
+ return;
+ }
+
+ efi_call_proto(apple_properties_protocol, get_all, p, NULL, &size);
+ if (!size)
+ return;
+
+ do {
+ status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
+ size + sizeof(struct setup_data), &new);
+ if (status != EFI_SUCCESS) {
+ efi_printk(sys_table,
+ "Failed to alloc mem for properties\n");
+ return;
+ }
+
+ status = efi_call_proto(apple_properties_protocol, get_all, p,
+ new->data, &size);
+
+ if (status == EFI_BUFFER_TOO_SMALL)
+ efi_call_early(free_pool, new);
+ } while (status == EFI_BUFFER_TOO_SMALL);
+
+ new->type = SETUP_APPLE_PROPERTIES;
+ new->len = size;
+ new->next = 0;
+
+ data = (struct setup_data *)(unsigned long)boot_params->hdr.setup_data;
+ if (!data)
+ boot_params->hdr.setup_data = (unsigned long)new;
+ else {
+ while (data->next)
+ data = (struct setup_data *)(unsigned long)data->next;
+ data->next = (unsigned long)new;
+ }
+}
+
+static void setup_quirks(struct boot_params *boot_params)
+{
+ efi_char16_t const apple[] = { 'A', 'p', 'p', 'l', 'e', 0 };
+ efi_char16_t *fw_vendor = (efi_char16_t *)(unsigned long)
+ efi_table_attr(efi_system_table, fw_vendor, sys_table);
+
+ if (!memcmp(fw_vendor, apple, sizeof(apple))) {
+ if (IS_ENABLED(CONFIG_APPLE_PROPERTIES))
+ retrieve_apple_device_properties(boot_params);
+ }
+}
+
static efi_status_t
setup_uga32(void **uga_handle, unsigned long size, u32 *width, u32 *height)
{
@@ -1098,6 +1161,8 @@ struct boot_params *efi_main(struct efi_config *c,

setup_efi_pci(boot_params);

+ setup_quirks(boot_params);
+
status = efi_call_early(allocate_pool, EFI_LOADER_DATA,
sizeof(*gdt), (void **)&gdt);
if (status != EFI_SUCCESS) {
diff --git a/arch/x86/include/uapi/asm/bootparam.h b/arch/x86/include/uapi/asm/bootparam.h
index c18ce67..b10bf31 100644
--- a/arch/x86/include/uapi/asm/bootparam.h
+++ b/arch/x86/include/uapi/asm/bootparam.h
@@ -7,6 +7,7 @@
#define SETUP_DTB 2
#define SETUP_PCI 3
#define SETUP_EFI 4
+#define SETUP_APPLE_PROPERTIES 5

/* ram_size flags */
#define RAMDISK_IMAGE_START_MASK 0x07FF
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index 893fda4..2e78b0b 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -129,6 +129,19 @@ config EFI_TEST
Say Y here to enable the runtime services support via /dev/efi_test.
If unsure, say N.

+config APPLE_PROPERTIES
+ bool "Apple Device Properties"
+ depends on EFI_STUB && X86
+ select EFI_DEV_PATH_PARSER
+ select UCS2_STRING
+ help
+ Retrieve properties from EFI on Apple Macs and assign them to
+ devices, allowing for improved support of Apple hardware.
+ Properties that would otherwise be missing include the
+ Thunderbolt Device ROM and GPU configuration data.
+
+ If unsure, say Y if you have a Mac. Otherwise N.
+
endmenu

config UEFI_CPER
diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile
index 3e91ae3..ad67342 100644
--- a/drivers/firmware/efi/Makefile
+++ b/drivers/firmware/efi/Makefile
@@ -22,6 +22,7 @@ obj-$(CONFIG_EFI_FAKE_MEMMAP) += fake_mem.o
obj-$(CONFIG_EFI_BOOTLOADER_CONTROL) += efibc.o
obj-$(CONFIG_EFI_TEST) += test/
obj-$(CONFIG_EFI_DEV_PATH_PARSER) += dev-path-parser.o
+obj-$(CONFIG_APPLE_PROPERTIES) += apple-properties.o

arm-obj-$(CONFIG_EFI) := arm-init.o arm-runtime.o
obj-$(CONFIG_ARM) += $(arm-obj-y)
diff --git a/drivers/firmware/efi/apple-properties.c b/drivers/firmware/efi/apple-properties.c
new file mode 100644
index 0000000..c473f4c
--- /dev/null
+++ b/drivers/firmware/efi/apple-properties.c
@@ -0,0 +1,248 @@
+/*
+ * apple-properties.c - EFI device properties on Macs
+ * Copyright (C) 2016 Lukas Wunner <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2) as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define pr_fmt(fmt) "apple-properties: " fmt
+
+#include <linux/bootmem.h>
+#include <linux/dmi.h>
+#include <linux/efi.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+#include <linux/ucs2_string.h>
+#include <asm/setup.h>
+
+static bool dump_properties __initdata;
+
+static int __init dump_properties_enable(char *arg)
+{
+ dump_properties = true;
+ return 0;
+}
+
+__setup("dump_apple_properties", dump_properties_enable);
+
+struct dev_header {
+ u32 len;
+ u32 prop_count;
+ struct efi_dev_path path[0];
+ /*
+ * followed by key/value pairs, each key and value preceded by u32 len,
+ * len includes itself, value may be empty (in which case its len is 4)
+ */
+};
+
+struct properties_header {
+ u32 len;
+ u32 version;
+ u32 dev_count;
+ struct dev_header dev_header[0];
+};
+
+static u8 one __initdata = 1;
+
+static void __init unmarshal_key_value_pairs(struct dev_header *dev_header,
+ struct device *dev, void *ptr,
+ struct property_entry entry[])
+{
+ int i;
+
+ for (i = 0; i < dev_header->prop_count; i++) {
+ int remaining = dev_header->len - (ptr - (void *)dev_header);
+ u32 key_len, val_len;
+ char *key;
+
+ if (sizeof(key_len) > remaining)
+ break;
+
+ key_len = *(typeof(key_len) *)ptr;
+ if (key_len + sizeof(val_len) > remaining ||
+ key_len < sizeof(key_len) + sizeof(efi_char16_t) ||
+ *(efi_char16_t *)(ptr + sizeof(key_len)) == 0) {
+ dev_err(dev, "invalid property name len at %#zx\n",
+ ptr - (void *)dev_header);
+ break;
+ }
+
+ val_len = *(typeof(val_len) *)(ptr + key_len);
+ if (key_len + val_len > remaining ||
+ val_len < sizeof(val_len)) {
+ dev_err(dev, "invalid property val len at %#zx\n",
+ ptr - (void *)dev_header + key_len);
+ break;
+ }
+
+ /* 4 bytes to accommodate UTF-8 code points + null byte */
+ key = kzalloc((key_len - sizeof(key_len)) * 4 + 1, GFP_KERNEL);
+ if (!key) {
+ dev_err(dev, "cannot allocate property name\n");
+ break;
+ }
+ ucs2_as_utf8(key, ptr + sizeof(key_len),
+ key_len - sizeof(key_len));
+
+ entry[i].name = key;
+ entry[i].is_array = true;
+ entry[i].length = val_len - sizeof(val_len);
+ entry[i].pointer.raw_data = ptr + key_len + sizeof(val_len);
+ if (!entry[i].length) {
+ /* driver core doesn't accept empty properties */
+ entry[i].length = 1;
+ entry[i].pointer.raw_data = &one;
+ }
+
+ if (dump_properties) {
+ dev_info(dev, "property: %s\n", entry[i].name);
+ print_hex_dump(KERN_INFO, pr_fmt(), DUMP_PREFIX_OFFSET,
+ 16, 1, entry[i].pointer.raw_data,
+ entry[i].length, true);
+ }
+
+ ptr += key_len + val_len;
+ }
+
+ if (i != dev_header->prop_count) {
+ dev_err(dev, "got %d device properties, expected %u\n", i,
+ dev_header->prop_count);
+ print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
+ 16, 1, dev_header, dev_header->len, true);
+ return;
+ }
+
+ dev_info(dev, "assigning %d device properties\n", i);
+}
+
+static int __init unmarshal_devices(struct properties_header *properties)
+{
+ size_t offset = offsetof(struct properties_header, dev_header[0]);
+
+ while (offset + sizeof(struct dev_header) < properties->len) {
+ struct dev_header *dev_header = (void *)properties + offset;
+ struct property_entry *entry = NULL;
+ struct device *dev;
+ size_t len;
+ int ret, i;
+ void *ptr;
+
+ if (offset + dev_header->len > properties->len ||
+ dev_header->len <= sizeof(*dev_header)) {
+ pr_err("invalid len in dev_header at %#zx\n", offset);
+ return -EINVAL;
+ }
+
+ ptr = dev_header->path;
+ len = dev_header->len - sizeof(*dev_header);
+
+ dev = efi_get_device_by_path((struct efi_dev_path **)&ptr, &len);
+ if (IS_ERR(dev)) {
+ pr_err("device path parse error %ld at %#zx:\n",
+ PTR_ERR(dev), ptr - (void *)dev_header);
+ print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
+ 16, 1, dev_header, dev_header->len, true);
+ dev = NULL;
+ goto skip_device;
+ }
+
+ entry = kcalloc(dev_header->prop_count + 1, sizeof(*entry),
+ GFP_KERNEL);
+ if (!entry) {
+ dev_err(dev, "cannot allocate properties\n");
+ goto skip_device;
+ }
+
+ unmarshal_key_value_pairs(dev_header, dev, ptr, entry);
+ if (!entry[0].name)
+ goto skip_device;
+
+ ret = device_add_properties(dev, entry); /* makes deep copy */
+ if (ret)
+ dev_err(dev, "error %d assigning properties\n", ret);
+
+ for (i = 0; entry[i].name; i++)
+ kfree(entry[i].name);
+
+skip_device:
+ kfree(entry);
+ put_device(dev);
+ offset += dev_header->len;
+ }
+
+ return 0;
+}
+
+static int __init map_properties(void)
+{
+ struct properties_header *properties;
+ struct setup_data *data;
+ u32 data_len;
+ u64 pa_data;
+ int ret;
+
+ if (!dmi_match(DMI_SYS_VENDOR, "Apple Inc.") &&
+ !dmi_match(DMI_SYS_VENDOR, "Apple Computer, Inc."))
+ return 0;
+
+ pa_data = boot_params.hdr.setup_data;
+ while (pa_data) {
+ data = ioremap(pa_data, sizeof(*data));
+ if (!data) {
+ pr_err("cannot map setup_data header\n");
+ return -ENOMEM;
+ }
+
+ if (data->type != SETUP_APPLE_PROPERTIES) {
+ pa_data = data->next;
+ iounmap(data);
+ continue;
+ }
+
+ data_len = data->len;
+ iounmap(data);
+
+ data = ioremap(pa_data, sizeof(*data) + data_len);
+ if (!data) {
+ pr_err("cannot map setup_data payload\n");
+ return -ENOMEM;
+ }
+
+ properties = (struct properties_header *)data->data;
+ if (properties->version != 1) {
+ pr_err("unsupported version:\n");
+ print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
+ 16, 1, properties, data_len, true);
+ ret = -ENOTSUPP;
+ } else if (properties->len != data_len) {
+ pr_err("length mismatch, expected %u\n", data_len);
+ print_hex_dump(KERN_ERR, pr_fmt(), DUMP_PREFIX_OFFSET,
+ 16, 1, properties, data_len, true);
+ ret = -EINVAL;
+ } else
+ ret = unmarshal_devices(properties);
+
+ /*
+ * Can only free the setup_data payload but not its header
+ * to avoid breaking the chain of ->next pointers.
+ */
+ data->len = 0;
+ iounmap(data);
+ free_bootmem_late(pa_data + sizeof(*data), data_len);
+
+ return ret;
+ }
+ return 0;
+}
+
+fs_initcall(map_properties);
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 2617672..a07a476 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -443,6 +443,22 @@ typedef struct {
#define EFI_PCI_IO_ATTRIBUTE_VGA_PALETTE_IO_16 0x20000
#define EFI_PCI_IO_ATTRIBUTE_VGA_IO_16 0x40000

+typedef struct {
+ u32 version;
+ u32 get;
+ u32 set;
+ u32 del;
+ u32 get_all;
+} apple_properties_protocol_32_t;
+
+typedef struct {
+ u64 version;
+ u64 get;
+ u64 set;
+ u64 del;
+ u64 get_all;
+} apple_properties_protocol_64_t;
+
/*
* Types and defines for EFI ResetSystem
*/
@@ -592,6 +608,7 @@ void efi_native_runtime_setup(void);
#define EFI_RNG_ALGORITHM_RAW EFI_GUID(0xe43176d7, 0xb6e8, 0x4827, 0xb7, 0x84, 0x7f, 0xfd, 0xc4, 0xb6, 0x85, 0x61)
#define EFI_MEMORY_ATTRIBUTES_TABLE_GUID EFI_GUID(0xdcfa911d, 0x26eb, 0x469f, 0xa2, 0x20, 0x38, 0xb7, 0xdc, 0x46, 0x12, 0x20)
#define EFI_CONSOLE_OUT_DEVICE_GUID EFI_GUID(0xd3b36f2c, 0xd551, 0x11d4, 0x9a, 0x46, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d)
+#define APPLE_PROPERTIES_PROTOCOL_GUID EFI_GUID(0x91bd12fe, 0xf6c3, 0x44fb, 0xa5, 0xb7, 0x51, 0x22, 0xab, 0x30, 0x3a, 0xe0)

/*
* This GUID is used to pass to the kernel proper the struct screen_info

Subject: [tip:efi/core] thunderbolt: Use Device ROM retrieved from EFI

Commit-ID: c9cc3aaa0281fec487794a473c82544bb7ac1b68
Gitweb: http://git.kernel.org/tip/c9cc3aaa0281fec487794a473c82544bb7ac1b68
Author: Lukas Wunner <[email protected]>
AuthorDate: Sat, 12 Nov 2016 21:32:37 +0000
Committer: Ingo Molnar <[email protected]>
CommitDate: Sun, 13 Nov 2016 08:23:16 +0100

thunderbolt: Use Device ROM retrieved from EFI

Macs with Thunderbolt 1 do not have a unit-specific DROM: The DROM is
empty with uid 0x1000000000000. (Apple started factory-burning a unit-
specific DROM with Thunderbolt 2.)

Instead, the NHI EFI driver supplies a DROM in a device property. Use
it if available. It's only available when booting with the efistub.
If it's not available, silently fall back to our hardcoded DROM.

The size of the DROM is always 256 bytes. The number is hardcoded into
the NHI EFI driver. This commit can deal with an arbitrary size however,
just in case they ever change that.

Background information: The EFI firmware volume contains ROM files for
the NHI, GMUX and several other chips as well as key material. This
strategy allows Apple to deploy ROM or key updates by simply publishing
an EFI firmware update on their website. Drivers do not access those
files directly but rather through a file server via EFI protocol
AC5E4829-A8FD-440B-AF33-9FFE013B12D8. Files are identified by GUID, the
NHI DROM has 339370BD-CFC6-4454-8EF7-704653120818.

The NHI EFI driver amends that file with a unit-specific uid. The uid
has 64 bit but its entropy is much lower: 24 bit represent the model,
24 bit are taken from a serial number, 16 bit are fixed. The NHI EFI
driver obtains the serial number via the DataHub protocol, copies it
into the DROM, calculates the CRC and submits the result as a device
property.

A modification is needed in the resume code where we currently read the
uid of all switches in the hierarchy to detect plug events that occurred
during sleep. On Thunderbolt 1 root switches this will now lead to a
mismatch between the uid of the empty DROM and the EFI DROM. Exempt the
root switch from this check: It's built in, so the uid should never
change. However we continue to *read* the uid of the root switch, this
seems like a good way to test its reachability after resume.

Tested-by: Lukas Wunner <[email protected]> [MacBookPro9,1]
Tested-by: Pierre Moreau <[email protected]> [MacBookPro11,3]
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
Acked-by: Andreas Noever <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Pedro Vilaça <[email protected]>
Cc: Peter Jones <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
drivers/thunderbolt/Kconfig | 1 +
drivers/thunderbolt/eeprom.c | 43 +++++++++++++++++++++++++++++++++++++++++++
drivers/thunderbolt/switch.c | 2 +-
3 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/drivers/thunderbolt/Kconfig b/drivers/thunderbolt/Kconfig
index c121acc..0056df7 100644
--- a/drivers/thunderbolt/Kconfig
+++ b/drivers/thunderbolt/Kconfig
@@ -1,6 +1,7 @@
menuconfig THUNDERBOLT
tristate "Thunderbolt support for Apple devices"
depends on PCI
+ select APPLE_PROPERTIES
select CRC32
help
Cactus Ridge Thunderbolt Controller driver
diff --git a/drivers/thunderbolt/eeprom.c b/drivers/thunderbolt/eeprom.c
index 2b9602c..6392990 100644
--- a/drivers/thunderbolt/eeprom.c
+++ b/drivers/thunderbolt/eeprom.c
@@ -5,6 +5,7 @@
*/

#include <linux/crc32.h>
+#include <linux/property.h>
#include <linux/slab.h>
#include "tb.h"

@@ -360,6 +361,40 @@ static int tb_drom_parse_entries(struct tb_switch *sw)
}

/**
+ * tb_drom_copy_efi - copy drom supplied by EFI to sw->drom if present
+ */
+static int tb_drom_copy_efi(struct tb_switch *sw, u16 *size)
+{
+ struct device *dev = &sw->tb->nhi->pdev->dev;
+ int len, res;
+
+ len = device_property_read_u8_array(dev, "ThunderboltDROM", NULL, 0);
+ if (len < 0 || len < sizeof(struct tb_drom_header))
+ return -EINVAL;
+
+ sw->drom = kmalloc(len, GFP_KERNEL);
+ if (!sw->drom)
+ return -ENOMEM;
+
+ res = device_property_read_u8_array(dev, "ThunderboltDROM", sw->drom,
+ len);
+ if (res)
+ goto err;
+
+ *size = ((struct tb_drom_header *)sw->drom)->data_len +
+ TB_DROM_DATA_START;
+ if (*size > len)
+ goto err;
+
+ return 0;
+
+err:
+ kfree(sw->drom);
+ sw->drom = NULL;
+ return -EINVAL;
+}
+
+/**
* tb_drom_read - copy drom to sw->drom and parse it
*/
int tb_drom_read(struct tb_switch *sw)
@@ -374,6 +409,13 @@ int tb_drom_read(struct tb_switch *sw)

if (tb_route(sw) == 0) {
/*
+ * Apple's NHI EFI driver supplies a DROM for the root switch
+ * in a device property. Use it if available.
+ */
+ if (tb_drom_copy_efi(sw, &size) == 0)
+ goto parse;
+
+ /*
* The root switch contains only a dummy drom (header only,
* no entries). Hardcode the configuration here.
*/
@@ -418,6 +460,7 @@ int tb_drom_read(struct tb_switch *sw)
if (res)
goto err;

+parse:
header = (void *) sw->drom;

if (header->data_len + TB_DROM_DATA_START != size) {
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index 9840fde..c6f30b1 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -460,7 +460,7 @@ int tb_switch_resume(struct tb_switch *sw)
tb_sw_warn(sw, "uid read failed\n");
return err;
}
- if (sw->uid != uid) {
+ if (sw != sw->tb->root_switch && sw->uid != uid) {
tb_sw_info(sw,
"changed while suspended (uid %#llx -> %#llx)\n",
sw->uid, uid);

2016-11-14 13:23:55

by Matt Fleming

[permalink] [raw]
Subject: Re: [PATCH 5/9] efi/arm*: libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table

On Sun, 13 Nov, at 08:19:39AM, Ingo Molnar wrote:
>
> * Matt Fleming <[email protected]> wrote:
>
> > From: Ard Biesheuvel <[email protected]>
> >
> > Invoke the EFI_RNG_PROTOCOL protocol in the context of the stub and
> > install the Linux-specific RNG seed UEFI config table. This will be
> > picked up by the EFI routines in the core kernel to seed the kernel
> > entropy pool.
> >
> > Cc: Matt Fleming <[email protected]>
> > Reviewed-by: Kees Cook <[email protected]>
> > Signed-off-by: Ard Biesheuvel <[email protected]>
>
> This commit (and the commits after this one) doesn't have a proper signoff chain,
> probably due to rebasing?

Argh, my bad. This is fallout from moving to the co-maintainer model.
My scripts assume they don't need to append a SoB because that was
handled when applying the patch to the git tree.

But that obviously doesn't hold if Ard applies the patch to git, but I
mail out the patches as part of the pull request (or vice versa).

I guess in future you'd wanna see the SoB of the person mailing the
patches, right?

> I'll apply the patches from email and add your SOB.

Thanks.

2016-11-14 13:28:38

by Matt Fleming

[permalink] [raw]
Subject: Re: [PATCH 5/9] efi/arm*: libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table

On Sun, 13 Nov, at 09:59:32AM, Ingo Molnar wrote:
>
> * Ingo Molnar <[email protected]> wrote:
>
> > I'll apply the patches from email and add your SOB.
>
> Note that the attached config produces this build error:
>
> drivers/firmware/efi/apple-properties.c:149:9: error: implicit declaration of function ‘efi_get_device_by_path’ [-Werror=implicit-function-declaration]
>
> also:
>
> warning: (THUNDERBOLT) selects APPLE_PROPERTIES which has unmet direct dependencies (EFI && EFI_STUB && X86)

Oops. Lukas, could you take a look at this (config attached).


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2016-11-14 13:55:28

by Ingo Molnar

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Subject: Re: [PATCH 5/9] efi/arm*: libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table


* Matt Fleming <[email protected]> wrote:

> On Sun, 13 Nov, at 08:19:39AM, Ingo Molnar wrote:
> >
> > * Matt Fleming <[email protected]> wrote:
> >
> > > From: Ard Biesheuvel <[email protected]>
> > >
> > > Invoke the EFI_RNG_PROTOCOL protocol in the context of the stub and
> > > install the Linux-specific RNG seed UEFI config table. This will be
> > > picked up by the EFI routines in the core kernel to seed the kernel
> > > entropy pool.
> > >
> > > Cc: Matt Fleming <[email protected]>
> > > Reviewed-by: Kees Cook <[email protected]>
> > > Signed-off-by: Ard Biesheuvel <[email protected]>
> >
> > This commit (and the commits after this one) doesn't have a proper signoff chain,
> > probably due to rebasing?
>
> Argh, my bad. This is fallout from moving to the co-maintainer model.
> My scripts assume they don't need to append a SoB because that was
> handled when applying the patch to the git tree.
>
> But that obviously doesn't hold if Ard applies the patch to git, but I
> mail out the patches as part of the pull request (or vice versa).
>
> I guess in future you'd wanna see the SoB of the person mailing the
> patches, right?

The problem is not that Ard applied the patches, but that you subsequently rebased
the tree. For example:

commit bf5d1f98c1d8be04a40eabb9dd6913347b1b3fc4
Author: Ard Biesheuvel <[email protected]>
AuthorDate: Thu Oct 20 12:21:26 2016 +0100
Commit: Matt Fleming <[email protected]>
CommitDate: Sat Nov 12 21:14:41 2016 +0000

efi/arm*: libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table

Invoke the EFI_RNG_PROTOCOL protocol in the context of the stub and
install the Linux-specific RNG seed UEFI config table. This will be
picked up by the EFI routines in the core kernel to seed the kernel
entropy pool.

Cc: Matt Fleming <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: Ard Biesheuvel <[email protected]>

if you rebase it (with your co-maintainer's permission) then you need to add your
SoB tag.

Thanks,

Ingo

2016-11-14 14:02:19

by Matt Fleming

[permalink] [raw]
Subject: Re: [PATCH 5/9] efi/arm*: libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table

On Mon, 14 Nov, at 02:55:22PM, Ingo Molnar wrote:
>
> The problem is not that Ard applied the patches, but that you subsequently rebased
> the tree. For example:
>
> commit bf5d1f98c1d8be04a40eabb9dd6913347b1b3fc4
> Author: Ard Biesheuvel <[email protected]>
> AuthorDate: Thu Oct 20 12:21:26 2016 +0100
> Commit: Matt Fleming <[email protected]>
> CommitDate: Sat Nov 12 21:14:41 2016 +0000
>
> efi/arm*: libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table
>
> Invoke the EFI_RNG_PROTOCOL protocol in the context of the stub and
> install the Linux-specific RNG seed UEFI config table. This will be
> picked up by the EFI routines in the core kernel to seed the kernel
> entropy pool.
>
> Cc: Matt Fleming <[email protected]>
> Reviewed-by: Kees Cook <[email protected]>
> Signed-off-by: Ard Biesheuvel <[email protected]>

Ah yes, this is exactly what happened.

> if you rebase it (with your co-maintainer's permission) then you need to add your
> SoB tag.

OK, will do so in future. Thanks Ingo.

2016-11-14 15:09:26

by Lukas Wunner

[permalink] [raw]
Subject: Re: [PATCH 5/9] efi/arm*: libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table

On Mon, Nov 14, 2016 at 01:27:08PM +0000, Matt Fleming wrote:
> On Sun, 13 Nov, at 09:59:32AM, Ingo Molnar wrote:
> > * Ingo Molnar <[email protected]> wrote:
> > > I'll apply the patches from email and add your SOB.
> >
> > Note that the attached config produces this build error:
> >
> > drivers/firmware/efi/apple-properties.c:149:9: error: implicit declaration of function ???efi_get_device_by_path??? [-Werror=implicit-function-declaration]
> >
> > also:
> >
> > warning: (THUNDERBOLT) selects APPLE_PROPERTIES which has unmet direct dependencies (EFI && EFI_STUB && X86)
>
> Oops. Lukas, could you take a look at this (config attached).

Sorry for the breakage, I think the simplest solution is to modify
the last commit on the tip.git efi/core branch like this:


diff --git a/drivers/thunderbolt/Kconfig b/drivers/thunderbolt/Kconfig
index 0056df7..bb0318c 100644
--- a/drivers/thunderbolt/Kconfig
+++ b/drivers/thunderbolt/Kconfig
@@ -1,7 +1,7 @@
menuconfig THUNDERBOLT
tristate "Thunderbolt support for Apple devices"
depends on PCI
- select APPLE_PROPERTIES
+ select APPLE_PROPERTIES if EFI_STUB
select CRC32
help
Cactus Ridge Thunderbolt Controller driver


A drop-in replacement commit is included below.

Thanks,

Lukas

-- >8 --
Subject: [PATCH] thunderbolt: Use Device ROM retrieved from EFI

Macs with Thunderbolt 1 do not have a unit-specific DROM: The DROM is
empty with uid 0x1000000000000. (Apple started factory-burning a unit-
specific DROM with Thunderbolt 2.)

Instead, the NHI EFI driver supplies a DROM in a device property. Use
it if available. It's only available when booting with the efistub.
If it's not available, silently fall back to our hardcoded DROM.

The size of the DROM is always 256 bytes. The number is hardcoded into
the NHI EFI driver. This commit can deal with an arbitrary size however,
just in case they ever change that.

Background information: The EFI firmware volume contains ROM files for
the NHI, GMUX and several other chips as well as key material. This
strategy allows Apple to deploy ROM or key updates by simply publishing
an EFI firmware update on their website. Drivers do not access those
files directly but rather through a file server via EFI protocol
AC5E4829-A8FD-440B-AF33-9FFE013B12D8. Files are identified by GUID, the
NHI DROM has 339370BD-CFC6-4454-8EF7-704653120818.

The NHI EFI driver amends that file with a unit-specific uid. The uid
has 64 bit but its entropy is much lower: 24 bit represent the model,
24 bit are taken from a serial number, 16 bit are fixed. The NHI EFI
driver obtains the serial number via the DataHub protocol, copies it
into the DROM, calculates the CRC and submits the result as a device
property.

A modification is needed in the resume code where we currently read the
uid of all switches in the hierarchy to detect plug events that occurred
during sleep. On Thunderbolt 1 root switches this will now lead to a
mismatch between the uid of the empty DROM and the EFI DROM. Exempt the
root switch from this check: It's built in, so the uid should never
change. However we continue to *read* the uid of the root switch, this
seems like a good way to test its reachability after resume.

Tested-by: Lukas Wunner <[email protected]> [MacBookPro9,1]
Tested-by: Pierre Moreau <[email protected]> [MacBookPro11,3]
Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
Acked-by: Andreas Noever <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Pedro Vilaça <[email protected]>
Cc: Peter Jones <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
drivers/thunderbolt/Kconfig | 1 +
drivers/thunderbolt/eeprom.c | 43 +++++++++++++++++++++++++++++++++++++++++++
drivers/thunderbolt/switch.c | 2 +-
3 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/drivers/thunderbolt/Kconfig b/drivers/thunderbolt/Kconfig
index c121acc..bb0318c 100644
--- a/drivers/thunderbolt/Kconfig
+++ b/drivers/thunderbolt/Kconfig
@@ -1,6 +1,7 @@
menuconfig THUNDERBOLT
tristate "Thunderbolt support for Apple devices"
depends on PCI
+ select APPLE_PROPERTIES if EFI_STUB
select CRC32
help
Cactus Ridge Thunderbolt Controller driver
diff --git a/drivers/thunderbolt/eeprom.c b/drivers/thunderbolt/eeprom.c
index 2b9602c..6392990 100644
--- a/drivers/thunderbolt/eeprom.c
+++ b/drivers/thunderbolt/eeprom.c
@@ -5,6 +5,7 @@
*/

#include <linux/crc32.h>
+#include <linux/property.h>
#include <linux/slab.h>
#include "tb.h"

@@ -360,6 +361,40 @@ static int tb_drom_parse_entries(struct tb_switch *sw)
}

/**
+ * tb_drom_copy_efi - copy drom supplied by EFI to sw->drom if present
+ */
+static int tb_drom_copy_efi(struct tb_switch *sw, u16 *size)
+{
+ struct device *dev = &sw->tb->nhi->pdev->dev;
+ int len, res;
+
+ len = device_property_read_u8_array(dev, "ThunderboltDROM", NULL, 0);
+ if (len < 0 || len < sizeof(struct tb_drom_header))
+ return -EINVAL;
+
+ sw->drom = kmalloc(len, GFP_KERNEL);
+ if (!sw->drom)
+ return -ENOMEM;
+
+ res = device_property_read_u8_array(dev, "ThunderboltDROM", sw->drom,
+ len);
+ if (res)
+ goto err;
+
+ *size = ((struct tb_drom_header *)sw->drom)->data_len +
+ TB_DROM_DATA_START;
+ if (*size > len)
+ goto err;
+
+ return 0;
+
+err:
+ kfree(sw->drom);
+ sw->drom = NULL;
+ return -EINVAL;
+}
+
+/**
* tb_drom_read - copy drom to sw->drom and parse it
*/
int tb_drom_read(struct tb_switch *sw)
@@ -374,6 +409,13 @@ int tb_drom_read(struct tb_switch *sw)

if (tb_route(sw) == 0) {
/*
+ * Apple's NHI EFI driver supplies a DROM for the root switch
+ * in a device property. Use it if available.
+ */
+ if (tb_drom_copy_efi(sw, &size) == 0)
+ goto parse;
+
+ /*
* The root switch contains only a dummy drom (header only,
* no entries). Hardcode the configuration here.
*/
@@ -418,6 +460,7 @@ int tb_drom_read(struct tb_switch *sw)
if (res)
goto err;

+parse:
header = (void *) sw->drom;

if (header->data_len + TB_DROM_DATA_START != size) {
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
index 9840fde..c6f30b1 100644
--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -460,7 +460,7 @@ int tb_switch_resume(struct tb_switch *sw)
tb_sw_warn(sw, "uid read failed\n");
return err;
}
- if (sw->uid != uid) {
+ if (sw != sw->tb->root_switch && sw->uid != uid) {
tb_sw_info(sw,
"changed while suspended (uid %#llx -> %#llx)\n",
sw->uid, uid);
--
2.10.1

Subject: [tip:efi/core] thunderbolt, efi: Fix Kconfig dependencies

Commit-ID: 79f9cd35b05e3e91ccf9b4038a8b74b9362b5da7
Gitweb: http://git.kernel.org/tip/79f9cd35b05e3e91ccf9b4038a8b74b9362b5da7
Author: Lukas Wunner <[email protected]>
AuthorDate: Mon, 14 Nov 2016 16:10:33 +0100
Committer: Ingo Molnar <[email protected]>
CommitDate: Tue, 15 Nov 2016 08:33:22 +0100

thunderbolt, efi: Fix Kconfig dependencies

Fix this EFI build failure on certain (rand)configs:

drivers/firmware/efi/apple-properties.c:149:9: error: implicit declaration of function ???efi_get_device_by_path??? [-Werror=implicit-function-declaration]

which is due to:

warning: (THUNDERBOLT) selects APPLE_PROPERTIES which has unmet direct dependencies (EFI && EFI_STUB && X86)

Signed-off-by: Lukas Wunner <[email protected]>
Cc: Andreas Noever <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Pedro Vilaça <[email protected]>
Cc: Peter Jones <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Pierre Moreau <[email protected]> [MacBookPro11,3]
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
drivers/thunderbolt/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/thunderbolt/Kconfig b/drivers/thunderbolt/Kconfig
index 0056df7..bb0318c 100644
--- a/drivers/thunderbolt/Kconfig
+++ b/drivers/thunderbolt/Kconfig
@@ -1,7 +1,7 @@
menuconfig THUNDERBOLT
tristate "Thunderbolt support for Apple devices"
depends on PCI
- select APPLE_PROPERTIES
+ select APPLE_PROPERTIES if EFI_STUB
select CRC32
help
Cactus Ridge Thunderbolt Controller driver