Re: [PATCH] tpm: Ensure that tpm chip has ops to check if it's defective

["Limonciello, Mario" <mario.limonciello@amd.com>]

On 6/23/2023 1:08 AM, Greg KH wrote:
> On Thu, Jun 22, 2023 at 10:04:27PM -0500, Mario Limonciello wrote:
>> The ibmvtpm doesn't have `chip->ops` set, and so trying to check
>> if it's a defective AMD fTPM doesn't work.
>>
>> Add an extra check to tpm_amd_is_rng_defective() to ensure the
>> TPM being checked has `chip->ops`.
>>
>> Cc: Linux regressions mailing list <regressions@lists.linux.dev>
>> Reported-by: Aneesh Kumar K. V <aneesh.kumar@linux.ibm.com>
>> Reported-by: Sachin Sant <sachinp@linux.ibm.com>
>> Link: https://lore.kernel.org/lkml/99B81401-DB46-49B9-B321-CF832B50CAC3@linux.ibm.com/
>> Tested-by: Sachin Sant <sachinp@linux.ibm.com>
>> Fixes: bd8621ca1510 ("tpm: Add !tpm_amd_is_rng_defective() to the hwrng_unregister() call site")
>> Fixes: f1324bbc4011 ("tpm: disable hwrng for fTPM on some AMD designs")
>> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
>> ---
>>   drivers/char/tpm/tpm-chip.c | 3 +++
>>   1 file changed, 3 insertions(+)
> No cc: stable on that list above?

Good point, my mistake on that miss.

If Jarkko agrees with the direction of this patch, I think
it can be added while committing.

Thanks!