[AMD Official Use Only]
> -----Original Message-----
> From: amd-gfx <[email protected]> On Behalf Of Marina
> Nikolic
> Sent: Monday, December 20, 2021 11:09 AM
> To: [email protected]
> Cc: Mitrovic, Milan <[email protected]>; Nikolic, Marina
> <[email protected]>; Kitchen, Greg <[email protected]>
> Subject: [PATCH] amdgpu/pm: Modify sysfs pp_dpm_sclk to have only read
> premission in
> ONEVF mode
>
> == Description ==
> Due to security reasons setting through sysfs
> should only be allowed in passthrough mode.
> Options that are not mapped as SMU messages
> do not have any mechanizm to distinguish between
> passthorugh, onevf and mutivf usecase.
> A unified approach is needed.
>
> == Changes ==
> This patch introduces a new mechanizm to distinguish
> ONEVF and PASSTHROUGH use case on sysfs level
> and prohibit setting (writting to sysfs).
> It also applies the new mechanizm on pp_dpm_sclk sysfs file.
>
> == Test ==
> Writing to pp_dpm_sclk sysfs file in passthrough mode will succeed.
> Writing to pp_dpm_sclk sysfs file in ONEVF mode will yield error:
> "calling process does not have sufficient permission to execute a command".
> Sysfs pp_dpm_sclk will not be created in MULTIVF mode.
>
> Signed-off-by: Marina Nikolic <[email protected]>
> ---
> drivers/gpu/drm/amd/pm/amdgpu_pm.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/pm/amdgpu_pm.c
> b/drivers/gpu/drm/amd/pm/amdgpu_pm.c
> index 082539c70fd4..d2b168babc7d 100644
> --- a/drivers/gpu/drm/amd/pm/amdgpu_pm.c
> +++ b/drivers/gpu/drm/amd/pm/amdgpu_pm.c
> @@ -2133,6 +2133,12 @@ static int default_attr_update(struct amdgpu_device
> *adev,
> struct amdgpu_device_
> }
> }
>
> + /* security: setting should not be allowed from VF */
> + if (amdgpu_sriov_vf(adev)) {
You should be checking for pp_dpm_sclk here, for example:
if (DEVICE_ATTR_IS(pp_dpm_sclk) {
Otherwise I am pretty sure you're setting this for every single file. And is it
only sclk? Or does it also need to affect mclk/fclk/etc? If it's only sclk, the
line above should help. If it's for more, then the commit should try to clarify
that as it's not 100% clear.
Kent
> + dev_attr->attr.mode &= ~S_IWUGO;
> + dev_attr->store = NULL;
> + }
> +
> #undef DEVICE_ATTR_IS
>
> return 0;
> --
> 2.20.1
