2023-01-10 19:23:00

by Jarkko Sakkinen

Subject: [PATCH v5] crypto: ccp: Sanitize sev_platform_init() error messages

The following functions end up calling sev_platform_init() or
__sev_platform_init_locked():

* sev_guest_init()
* sev_ioctl_do_pek_csr
* sev_ioctl_do_pdh_export()
* sev_ioctl_do_pek_import()
* sev_ioctl_do_pek_pdh_gen()
* sev_pci_init()

However, only sev_pci_init() prints out the failed command error code, and
even there, the error message does not specify which SEV command failed.

Address this by printing out the SEV command errors inside
__sev_platform_init_locked(), and differentiate between DF_FLUSH, INIT and
INIT_EX commands. As a side-effect, @error can be removed from the
parameter list.

This extra information is particularly useful if firmware loading and/or
initialization is going to be made more robust, e.g. by allowing firmware
loading to be postponed.

Signed-off-by: Jarkko Sakkinen <[email protected]>
---
v5:
* Address Tom's feedback:
https://lore.kernel.org/all/[email protected]/
* "failed error" -> "error"
* "SEV_CMD_" -> ""

v4:
* Sorry, v3 was malformed. Here's a proper patch.

v3:
* Address Tom Lendacky's feedback:
https://lore.kernel.org/kvm/[email protected]/

v2:
* Address David Rientjes's feedback:
https://lore.kernel.org/all/[email protected]/
* Remove @error.
* Remove "SEV_" prefix: it is obvious from context so no need to make klog
line longer.
---
drivers/crypto/ccp/sev-dev.c | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
index 06fc7156c04f..3f80cd39cbdf 100644
--- a/drivers/crypto/ccp/sev-dev.c
+++ b/drivers/crypto/ccp/sev-dev.c
@@ -478,17 +478,23 @@ static int __sev_platform_init_locked(int *error)
}
if (error)
*error = psp_ret;
-
- if (rc)
+ if (rc) {
+ dev_err(sev->dev, "SEV: %s error %#x",
+ sev_init_ex_buffer ? "INIT_EX" : "INIT", psp_ret);
return rc;
+ }

sev->state = SEV_STATE_INIT;

/* Prepare for first SEV guest launch after INIT */
wbinvd_on_all_cpus();
- rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error);
- if (rc)
+ rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, &psp_ret);
+ if (error)
+ *error = psp_ret;
+ if (rc) {
+ dev_err(sev->dev, "SEV: DF_FLUSH error %#x", psp_ret);
return rc;
+ }

dev_dbg(sev->dev, "SEV firmware initialized\n");

@@ -1337,8 +1343,7 @@ void sev_pci_init(void)
/* Initialize the platform */
rc = sev_platform_init(&error);
if (rc)
- dev_err(sev->dev, "SEV: failed to INIT error %#x, rc %d\n",
- error, rc);
+ dev_err(sev->dev, "SEV: failed to INIT rc %d\n", rc);

return;

--
2.38.1

2023-01-20 10:12:32

by Herbert Xu

Subject: Re: [PATCH v5] crypto: ccp: Sanitize sev_platform_init() error messages

On Tue, Jan 10, 2023 at 07:12:00PM +0000, Jarkko Sakkinen wrote:
>
> @@ -1337,8 +1343,7 @@ void sev_pci_init(void)
> /* Initialize the platform */
> rc = sev_platform_init(&error);
> if (rc)
> - dev_err(sev->dev, "SEV: failed to INIT error %#x, rc %d\n",
> - error, rc);
> + dev_err(sev->dev, "SEV: failed to INIT rc %d\n", rc);

Please remove error and replace it with NULL.

Thanks,
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt