On 10/19/19 3:59 AM, David Rientjes wrote:
> On Thu, 17 Oct 2019, Kalra, Ashish wrote:
>
>> From: Ashish Kalra <ashish.kalra@xxxxxxx>
>>
>> SEV INIT command loads the SEV related persistent data from NVS
>> and initializes the platform context. The firmware validates the
>> persistent state. If validation fails, the firmware will reset
>> the persisent state and return an integrity check failure status.
>>
>> At this point, a subsequent INIT command should succeed, so retry
>> the command. The INIT command retry is only done during driver
>> initialization.
>>
>> Additional enums along with SEV_RET_SECURE_DATA_INVALID are added
>> to sev_ret_code to maintain continuity and relevance of enum values.
>>
>> Signed-off-by: Ashish Kalra <ashish.kalra@xxxxxxx>
>> ---
>> drivers/crypto/ccp/psp-dev.c | 12 ++++++++++++
>> include/uapi/linux/psp-sev.h | 3 +++
>> 2 files changed, 15 insertions(+)
>>
>> diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
>> index 6b17d179ef8a..f9318d4482f2 100644
>> --- a/drivers/crypto/ccp/psp-dev.c
>> +++ b/drivers/crypto/ccp/psp-dev.c
>> @@ -1064,6 +1064,18 @@ void psp_pci_init(void)
>>
>> /* Initialize the platform */
>> rc = sev_platform_init(&error);
>> + if (rc && (error == SEV_RET_SECURE_DATA_INVALID)) {
>> + /*
>> + * INIT command returned an integrity check failure
>> + * status code, meaning that firmware load and
>> + * validation of SEV related persistent data has
>> + * failed and persistent state has been erased.
>> + * Retrying INIT command here should succeed.
>> + */
>> + dev_dbg(sp->dev, "SEV: retrying INIT command");
>> + rc = sev_platform_init(&error);
>> + }
>> +
>> if (rc) {
>> dev_err(sp->dev, "SEV: failed to INIT error %#x\n", error);
>> return;
>
> Curious why this isn't done in __sev_platform_init_locked() since
> sev_platform_init() can be called when loading the kvm module and the same
> init failure can happen that way.
>
The FW initialization (aka PLATFORM_INIT) is called in the following
code paths:
1. During system boot up
and
2. After the platform reset command is issued
The patch takes care of #1. Based on the spec, platform reset command
should erase the persistent data and the PLATFORM_INIT should *not* fail
with SEV_RET_SECURE_DATA_INVALID error code. So, I am not able to see
any strong reason to move the retry code in
__sev_platform_init_locked().
thanks
