From: Vitaly Prosyak <vitaly.prosyak@xxxxxxx> We allow sending PSP messages LOAD_ASD and UNLOAD_TA without acquiring a lock in drm_dev_enter during driver unload because we must call drm_dev_unplug as the beginning of unload driver sequence. Added WARNING if other PSP messages are sent without a lock. After this commit, the following commands would work -sudo modprobe -r amdgpu -sudo modeprobe amdgpu Signed-off-by: Vitaly Prosyak <vitaly.prosyak@xxxxxxx> Reviewed-by Alex Deucher <alexander.deucher@xxxxxxx> --- drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c index a8391f269cd0..7ef18e062c0e 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c @@ -606,12 +606,21 @@ psp_cmd_submit_buf(struct psp_context *psp, int timeout = 20000; bool ras_intr = false; bool skip_unsupport = false; + bool dev_entered; if (psp->adev->no_hw_access) return 0; - if (!drm_dev_enter(adev_to_drm(psp->adev), &idx)) - return 0; + dev_entered = drm_dev_enter(adev_to_drm(psp->adev), &idx); + /* + * We allow sending PSP messages LOAD_ASD and UNLOAD_TA without acquiring + * a lock in drm_dev_enter during driver unload because we must call + * drm_dev_unplug as the beginning of unload driver sequence . It is very + * crucial that userspace can't access device instances anymore. + */ + if (!dev_entered) + WARN_ON(psp->cmd_buf_mem->cmd_id != GFX_CMD_ID_LOAD_ASD && + psp->cmd_buf_mem->cmd_id != GFX_CMD_ID_UNLOAD_TA); memset(psp->cmd_buf_mem, 0, PSP_CMD_BUFFER_SIZE); @@ -676,7 +685,8 @@ psp_cmd_submit_buf(struct psp_context *psp, } exit: - drm_dev_exit(idx); + if (dev_entered == true ) + drm_dev_exit(idx); return ret; } -- 2.25.1
