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

From: Greg KH
Date: Fri Jun 23 2023 - 02:08:43 EST


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@xxxxxxxxxxxxxxx>
> Reported-by: Aneesh Kumar K. V <aneesh.kumar@xxxxxxxxxxxxx>
> Reported-by: Sachin Sant <sachinp@xxxxxxxxxxxxx>
> Link: https://lore.kernel.org/lkml/99B81401-DB46-49B9-B321-CF832B50CAC3@xxxxxxxxxxxxx/
> Tested-by: Sachin Sant <sachinp@xxxxxxxxxxxxx>
> 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@xxxxxxx>
> ---
> drivers/char/tpm/tpm-chip.c | 3 +++
> 1 file changed, 3 insertions(+)

No cc: stable on that list above?

greg k-h