2022-08-08 00:17:21

by Jarkko Sakkinen

[permalink] [raw]
Subject: [PATCH] crypto: ccp: Add a quirk to firmware update

From: Jarkko Sakkinen <[email protected]>

A quirk for fixing the committed TCB version, when upgrading from earlier
firmware version than 1.33.01. This is a known issue, and the documented
workaround is to load the firmware twice.

The issue realizes in a machine where the upgrade is done from firmware
reporting having SEV API version 1.49, and requires the following
workaround:

sudo modprobe -r kvm_amd
sudo modprobe -r ccp
sudo modprobe ccp
sudo modprobe kvm_amd

Implement this workaround inside kernel by checking whether the API
version is less than 1.50, and if so, download the firmware twice.
This addresses the TCB version issue.

Link: https://lore.kernel.org/all/[email protected]/
Reported-by: Harald Hoyer <[email protected]>
Signed-off-by: Jarkko Sakkinen <[email protected]>
---
drivers/crypto/ccp/sev-dev.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
index 799b476fc3e8..8ae26c5c64f6 100644
--- a/drivers/crypto/ccp/sev-dev.c
+++ b/drivers/crypto/ccp/sev-dev.c
@@ -742,6 +742,11 @@ static int sev_update_firmware(struct device *dev)
struct page *p;
u64 data_size;

+ if (!sev_version_greater_or_equal(0, 15)) {
+ dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n");
+ return -1;
+ }
+
if (sev_get_firmware(dev, &firmware) == -ENOENT) {
dev_dbg(dev, "No SEV firmware file present\n");
return -1;
@@ -774,6 +779,14 @@ static int sev_update_firmware(struct device *dev)
data->len = firmware->size;

ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
+
+ /*
+ * A quirk for fixing the committed TCB version, when upgrading from
+ * earlier firmware version than 1.33.01.
+ */
+ if (!ret && !sev_version_greater_or_equal(1, 50))
+ ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
+
if (ret)
dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
else
@@ -1283,8 +1296,7 @@ void sev_pci_init(void)
if (sev_get_api_version())
goto err;

- if (sev_version_greater_or_equal(0, 15) &&
- sev_update_firmware(sev->dev) == 0)
+ if (sev_update_firmware(sev->dev) == 0)
sev_get_api_version();

/* If an init_ex_path is provided rely on INIT_EX for PSP initialization
--
2.37.1


2022-08-09 15:58:49

by Tom Lendacky

[permalink] [raw]
Subject: Re: [PATCH] crypto: ccp: Add a quirk to firmware update

On 8/7/22 19:15, Jarkko Sakkinen wrote:
> From: Jarkko Sakkinen <[email protected]>

Looks good, just some minor commit message and comment changes requested.

>
> A quirk for fixing the committed TCB version, when upgrading from earlier
> firmware version than 1.33.01. This is a known issue, and the documented

", when upgrading from earlier firmware version than 1.33.01" => "when
upgrading from a firmware version earlier than 1.50"

> workaround is to load the firmware twice.
>
> The issue realizes in a machine where the upgrade is done from firmware
> reporting having SEV API version 1.49, and requires the following
> workaround:

Replace the above paragraph with just: "Currently, this issue requires the
following workaround:"

>
> sudo modprobe -r kvm_amd
> sudo modprobe -r ccp
> sudo modprobe ccp
> sudo modprobe kvm_amd
>
> Implement this workaround inside kernel by checking whether the API
> version is less than 1.50, and if so, download the firmware twice.
> This addresses the TCB version issue.
>
> Link: https://lore.kernel.org/all/[email protected]/
> Reported-by: Harald Hoyer <[email protected]>
> Signed-off-by: Jarkko Sakkinen <[email protected]>
> ---
> drivers/crypto/ccp/sev-dev.c | 16 ++++++++++++++--
> 1 file changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
> index 799b476fc3e8..8ae26c5c64f6 100644
> --- a/drivers/crypto/ccp/sev-dev.c
> +++ b/drivers/crypto/ccp/sev-dev.c
> @@ -742,6 +742,11 @@ static int sev_update_firmware(struct device *dev)
> struct page *p;
> u64 data_size;
>
> + if (!sev_version_greater_or_equal(0, 15)) {
> + dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n");
> + return -1;
> + }
> +
> if (sev_get_firmware(dev, &firmware) == -ENOENT) {
> dev_dbg(dev, "No SEV firmware file present\n");
> return -1;
> @@ -774,6 +779,14 @@ static int sev_update_firmware(struct device *dev)
> data->len = firmware->size;
>
> ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
> +
> + /*
> + * A quirk for fixing the committed TCB version, when upgrading from
> + * earlier firmware version than 1.33.01.

s/1.33.01/1.50/

Thanks,
Tom

> + */
> + if (!ret && !sev_version_greater_or_equal(1, 50))
> + ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
> +
> if (ret)
> dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
> else
> @@ -1283,8 +1296,7 @@ void sev_pci_init(void)
> if (sev_get_api_version())
> goto err;
>
> - if (sev_version_greater_or_equal(0, 15) &&
> - sev_update_firmware(sev->dev) == 0)
> + if (sev_update_firmware(sev->dev) == 0)
> sev_get_api_version();
>
> /* If an init_ex_path is provided rely on INIT_EX for PSP initialization

2022-08-09 19:12:58

by Jarkko Sakkinen

[permalink] [raw]
Subject: Re: [PATCH] crypto: ccp: Add a quirk to firmware update

On Tue, Aug 09, 2022 at 10:57:16AM -0500, Tom Lendacky wrote:
> On 8/7/22 19:15, Jarkko Sakkinen wrote:
> > From: Jarkko Sakkinen <[email protected]>
>
> Looks good, just some minor commit message and comment changes requested.
>
> >
> > A quirk for fixing the committed TCB version, when upgrading from earlier
> > firmware version than 1.33.01. This is a known issue, and the documented
>
> ", when upgrading from earlier firmware version than 1.33.01" => "when
> upgrading from a firmware version earlier than 1.50"
>
> > workaround is to load the firmware twice.
> >
> > The issue realizes in a machine where the upgrade is done from firmware
> > reporting having SEV API version 1.49, and requires the following
> > workaround:
>
> Replace the above paragraph with just: "Currently, this issue requires the
> following workaround:"
>
> >
> > sudo modprobe -r kvm_amd
> > sudo modprobe -r ccp
> > sudo modprobe ccp
> > sudo modprobe kvm_amd
> >
> > Implement this workaround inside kernel by checking whether the API
> > version is less than 1.50, and if so, download the firmware twice.
> > This addresses the TCB version issue.
> >
> > Link: https://lore.kernel.org/all/[email protected]/
> > Reported-by: Harald Hoyer <[email protected]>
> > Signed-off-by: Jarkko Sakkinen <[email protected]>
> > ---
> > drivers/crypto/ccp/sev-dev.c | 16 ++++++++++++++--
> > 1 file changed, 14 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
> > index 799b476fc3e8..8ae26c5c64f6 100644
> > --- a/drivers/crypto/ccp/sev-dev.c
> > +++ b/drivers/crypto/ccp/sev-dev.c
> > @@ -742,6 +742,11 @@ static int sev_update_firmware(struct device *dev)
> > struct page *p;
> > u64 data_size;
> > + if (!sev_version_greater_or_equal(0, 15)) {
> > + dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n");
> > + return -1;
> > + }
> > +
> > if (sev_get_firmware(dev, &firmware) == -ENOENT) {
> > dev_dbg(dev, "No SEV firmware file present\n");
> > return -1;
> > @@ -774,6 +779,14 @@ static int sev_update_firmware(struct device *dev)
> > data->len = firmware->size;
> > ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
> > +
> > + /*
> > + * A quirk for fixing the committed TCB version, when upgrading from
> > + * earlier firmware version than 1.33.01.
>
> s/1.33.01/1.50/
>
> Thanks,
> Tom

Thanks Tom, I'll address the issues and send a new version.

BR, Jarkko