Hi all,
The patchset:
- refactors the VMBus negotiation code by introducing the table of
VMBus protocol versions (patch 1/3),
- enables VMBus protocol version 4.1, 5.1 and 5.2 (patch 2/3),
- introduces a module parameter to cap the VMBus protocol versions
which a guest can negotiate with the hypervisor (patch 3/3).
Thanks,
Andrea
---
Changes since v1 ([1]):
- remove the VERSION_INVAL macro (Vitaly Kuznetsov and Dexuan Cui)
- make the table of VMBus protocol versions static (Dexuan Cui)
- enable VMBus protocol version 4.1 (Michael Kelley)
- introduce module parameter to cap the VMBus version (Dexuan Cui)
[1] https://lkml.kernel.org/r/[email protected]
Andrea Parri (3):
Drivers: hv: vmbus: Introduce table of VMBus protocol versions
Drivers: hv: vmbus: Enable VMBus protocol versions 4.1, 5.1 and 5.2
Drivers: hv: vmbus: Add module parameter to cap the VMBus version
drivers/hv/connection.c | 68 ++++++++++++++++----------------
drivers/hv/vmbus_drv.c | 3 +-
drivers/net/hyperv/netvsc.c | 6 +--
include/linux/hyperv.h | 12 +++---
net/vmw_vsock/hyperv_transport.c | 4 +-
5 files changed, 48 insertions(+), 45 deletions(-)
--
2.23.0
Currently, Linux guests negotiate the VMBus version with Hyper-V
and use the highest available VMBus version they can connect to.
This has some drawbacks: by using the highest available version,
certain code paths are never executed and can not be tested when
the guest runs on the newest host.
Add the module parameter "max_version", to upper-bound the VMBus
versions guests can negotiate.
Suggested-by: Dexuan Cui <[email protected]>
Signed-off-by: Andrea Parri <[email protected]>
---
drivers/hv/connection.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index 2f6961ac8c996..f60d7330ff3fd 100644
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -14,6 +14,7 @@
#include <linux/wait.h>
#include <linux/delay.h>
#include <linux/mm.h>
+#include <linux/module.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/hyperv.h>
@@ -55,6 +56,16 @@ static __u32 vmbus_versions[] = {
VERSION_WS2008
};
+/*
+ * Maximal VMBus protocol version guests can negotiate. Useful to cap the
+ * VMBus version for testing and debugging purpose.
+ */
+static uint max_version = VERSION_WIN10_V5_2;
+
+module_param(max_version, uint, S_IRUGO);
+MODULE_PARM_DESC(max_version,
+ "Maximal VMBus protocol version which can be negotiated");
+
int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version)
{
int ret = 0;
@@ -237,6 +248,8 @@ int vmbus_connect(void)
for (i = 0; i < ARRAY_SIZE(vmbus_versions); i++) {
version = vmbus_versions[i];
+ if (version > max_version)
+ continue;
ret = vmbus_negotiate_version(msginfo, version);
if (ret == -ETIMEDOUT)
--
2.23.0
Hyper-V has added VMBus protocol versions 5.1 and 5.2 in recent release
versions. Allow Linux guests to negotiate these new protocol versions
on versions of Hyper-V that support them. While on this, also allow
guests to negotiate the VMBus protocol version 4.1 (which was missing).
Signed-off-by: Andrea Parri <[email protected]>
---
drivers/hv/connection.c | 15 +++++++++------
drivers/net/hyperv/netvsc.c | 6 +++---
include/linux/hyperv.h | 8 +++++++-
net/vmw_vsock/hyperv_transport.c | 4 ++--
4 files changed, 21 insertions(+), 12 deletions(-)
diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index b1f805426e6b4..2f6961ac8c996 100644
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -44,8 +44,11 @@ EXPORT_SYMBOL_GPL(vmbus_proto_version);
* Table of VMBus versions listed from newest to oldest.
*/
static __u32 vmbus_versions[] = {
+ VERSION_WIN10_V5_2,
+ VERSION_WIN10_V5_1,
VERSION_WIN10_V5,
- VERSION_WIN10,
+ VERSION_WIN10_V4_1,
+ VERSION_WIN10_V4,
VERSION_WIN8_1,
VERSION_WIN8,
VERSION_WIN7,
@@ -68,12 +71,12 @@ int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version)
msg->vmbus_version_requested = version;
/*
- * VMBus protocol 5.0 (VERSION_WIN10_V5) requires that we must use
- * VMBUS_MESSAGE_CONNECTION_ID_4 for the Initiate Contact Message,
+ * VMBus protocol 5.0 (VERSION_WIN10_V5) and higher require that we must
+ * use VMBUS_MESSAGE_CONNECTION_ID_4 for the Initiate Contact Message,
* and for subsequent messages, we must use the Message Connection ID
* field in the host-returned Version Response Message. And, with
- * VERSION_WIN10_V5, we don't use msg->interrupt_page, but we tell
- * the host explicitly that we still use VMBUS_MESSAGE_SINT(2) for
+ * VERSION_WIN10_V5 and higher, we don't use msg->interrupt_page, but we
+ * tell the host explicitly that we still use VMBUS_MESSAGE_SINT(2) for
* compatibility.
*
* On old hosts, we should always use VMBUS_MESSAGE_CONNECTION_ID (1).
@@ -399,7 +402,7 @@ int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep)
case HV_STATUS_INVALID_CONNECTION_ID:
/*
* See vmbus_negotiate_version(): VMBus protocol 5.0
- * requires that we must use
+ * and higher require that we must use
* VMBUS_MESSAGE_CONNECTION_ID_4 for the Initiate
* Contact message, but on old hosts that only
* support VMBus protocol 4.0 or lower, here we get
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index d22a36fc7a7c6..d4c1a776b314a 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -624,11 +624,11 @@ void netvsc_device_remove(struct hv_device *device)
* receive buffer GPADL. Do the same for send buffer.
*/
netvsc_revoke_recv_buf(device, net_device, ndev);
- if (vmbus_proto_version < VERSION_WIN10)
+ if (vmbus_proto_version < VERSION_WIN10_V4)
netvsc_teardown_recv_gpadl(device, net_device, ndev);
netvsc_revoke_send_buf(device, net_device, ndev);
- if (vmbus_proto_version < VERSION_WIN10)
+ if (vmbus_proto_version < VERSION_WIN10_V4)
netvsc_teardown_send_gpadl(device, net_device, ndev);
RCU_INIT_POINTER(net_device_ctx->nvdev, NULL);
@@ -650,7 +650,7 @@ void netvsc_device_remove(struct hv_device *device)
* If host is Win2016 or higher then we do the GPADL tear down
* here after VMBus is closed.
*/
- if (vmbus_proto_version >= VERSION_WIN10) {
+ if (vmbus_proto_version >= VERSION_WIN10_V4) {
netvsc_teardown_recv_gpadl(device, net_device, ndev);
netvsc_teardown_send_gpadl(device, net_device, ndev);
}
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index c08b62dbd151f..a4f80e30b0207 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -182,15 +182,21 @@ static inline u32 hv_get_avail_to_write_percent(
* 2 . 4 (Windows 8)
* 3 . 0 (Windows 8 R2)
* 4 . 0 (Windows 10)
+ * 4 . 1 (Windows 10 RS3)
* 5 . 0 (Newer Windows 10)
+ * 5 . 1 (Windows 10 RS4)
+ * 5 . 2 (Windows Server 2019, RS5)
*/
#define VERSION_WS2008 ((0 << 16) | (13))
#define VERSION_WIN7 ((1 << 16) | (1))
#define VERSION_WIN8 ((2 << 16) | (4))
#define VERSION_WIN8_1 ((3 << 16) | (0))
-#define VERSION_WIN10 ((4 << 16) | (0))
+#define VERSION_WIN10_V4 ((4 << 16) | (0))
+#define VERSION_WIN10_V4_1 ((4 << 16) | (1))
#define VERSION_WIN10_V5 ((5 << 16) | (0))
+#define VERSION_WIN10_V5_1 ((5 << 16) | (1))
+#define VERSION_WIN10_V5_2 ((5 << 16) | (2))
/* Make maximum size of pipe payload of 16K */
#define MAX_PIPE_DATA_PAYLOAD (sizeof(u8) * 16384)
diff --git a/net/vmw_vsock/hyperv_transport.c b/net/vmw_vsock/hyperv_transport.c
index c443db7af8d4a..cb0dbae4de14a 100644
--- a/net/vmw_vsock/hyperv_transport.c
+++ b/net/vmw_vsock/hyperv_transport.c
@@ -14,7 +14,7 @@
#include <net/sock.h>
#include <net/af_vsock.h>
-/* Older (VMBUS version 'VERSION_WIN10' or before) Windows hosts have some
+/* Older (VMBUS version 'VERSION_WIN10_V4' or before) Windows hosts have some
* stricter requirements on the hv_sock ring buffer size of six 4K pages. Newer
* hosts don't have this limitation; but, keep the defaults the same for compat.
*/
@@ -955,7 +955,7 @@ static int __init hvs_init(void)
{
int ret;
- if (vmbus_proto_version < VERSION_WIN10)
+ if (vmbus_proto_version < VERSION_WIN10_V4)
return -ENODEV;
ret = vmbus_driver_register(&hvs_drv);
--
2.23.0
From: Andrea Parri <[email protected]> Sent: Thursday, October 10, 2019 8:46 AM
>
> Hyper-V has added VMBus protocol versions 5.1 and 5.2 in recent release
> versions. Allow Linux guests to negotiate these new protocol versions
> on versions of Hyper-V that support them. While on this, also allow
> guests to negotiate the VMBus protocol version 4.1 (which was missing).
>
> Signed-off-by: Andrea Parri <[email protected]>
> ---
> drivers/hv/connection.c | 15 +++++++++------
> drivers/net/hyperv/netvsc.c | 6 +++---
> include/linux/hyperv.h | 8 +++++++-
> net/vmw_vsock/hyperv_transport.c | 4 ++--
> 4 files changed, 21 insertions(+), 12 deletions(-)
>
> diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
> index c08b62dbd151f..a4f80e30b0207 100644
> --- a/include/linux/hyperv.h
> +++ b/include/linux/hyperv.h
> @@ -182,15 +182,21 @@ static inline u32 hv_get_avail_to_write_percent(
> * 2 . 4 (Windows 8)
> * 3 . 0 (Windows 8 R2)
> * 4 . 0 (Windows 10)
> + * 4 . 1 (Windows 10 RS3)
> * 5 . 0 (Newer Windows 10)
> + * 5 . 1 (Windows 10 RS4)
> + * 5 . 2 (Windows Server 2019, RS5)
> */
>
> #define VERSION_WS2008 ((0 << 16) | (13))
> #define VERSION_WIN7 ((1 << 16) | (1))
> #define VERSION_WIN8 ((2 << 16) | (4))
> #define VERSION_WIN8_1 ((3 << 16) | (0))
> -#define VERSION_WIN10 ((4 << 16) | (0))
> +#define VERSION_WIN10_V4 ((4 << 16) | (0))
I would recommend not changing the symbol name for version 4.0.
The change makes it more consistent with the later VERSION_WIN10_*
symbols, but it doesn't fundamentally add any clarity and I'm not sure
it's worth the churn in the other files that have to be touched. It's a
judgment call, and that's just my input.
> +#define VERSION_WIN10_V4_1 ((4 << 16) | (1))
> #define VERSION_WIN10_V5 ((5 << 16) | (0))
> +#define VERSION_WIN10_V5_1 ((5 << 16) | (1))
> +#define VERSION_WIN10_V5_2 ((5 << 16) | (2))
>
Michael
> > @@ -182,15 +182,21 @@ static inline u32 hv_get_avail_to_write_percent(
> > * 2 . 4 (Windows 8)
> > * 3 . 0 (Windows 8 R2)
> > * 4 . 0 (Windows 10)
> > + * 4 . 1 (Windows 10 RS3)
> > * 5 . 0 (Newer Windows 10)
> > + * 5 . 1 (Windows 10 RS4)
> > + * 5 . 2 (Windows Server 2019, RS5)
> > */
> >
> > #define VERSION_WS2008 ((0 << 16) | (13))
> > #define VERSION_WIN7 ((1 << 16) | (1))
> > #define VERSION_WIN8 ((2 << 16) | (4))
> > #define VERSION_WIN8_1 ((3 << 16) | (0))
> > -#define VERSION_WIN10 ((4 << 16) | (0))
> > +#define VERSION_WIN10_V4 ((4 << 16) | (0))
>
> I would recommend not changing the symbol name for version 4.0.
> The change makes it more consistent with the later VERSION_WIN10_*
> symbols, but it doesn't fundamentally add any clarity and I'm not sure
> it's worth the churn in the other files that have to be touched. It's a
> judgment call, and that's just my input.
My fingers were itching: ;-) I've reverted this change, following
your recommendation.
Thanks,
Andrea