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

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

[Jarkko Sakkinen]

From: Jarkko Sakkinen <jarkko@profian.com>

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/de02389f-249d-f565-1136-4af3655fab2a@profian.com/
Reported-by: Harald Hoyer <harald@profian.com>
Signed-off-by: Jarkko Sakkinen <jarkko@profian.com>
---
 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

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

[Tom Lendacky]

On 8/7/22 19:15, Jarkko Sakkinen wrote:
> From: Jarkko Sakkinen <jarkko@profian.com>

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/de02389f-249d-f565-1136-4af3655fab2a@profian.com/
> Reported-by: Harald Hoyer <harald@profian.com>
> Signed-off-by: Jarkko Sakkinen <jarkko@profian.com>
> ---
>   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

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

[Jarkko Sakkinen]

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 <jarkko@profian.com>
> 
> 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/de02389f-249d-f565-1136-4af3655fab2a@profian.com/
> > Reported-by: Harald Hoyer <harald@profian.com>
> > Signed-off-by: Jarkko Sakkinen <jarkko@profian.com>
> > ---
> >   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