From: Mario Limonciello mario.limonciello@amd.com
commit 3eb1a3a04056ba3df3205e169b8acc9da0c65a94 upstream.
The VBIOS image update flow requires userspace to: 1) Write the image to `psp_vbflash` 2) Read `psp_vbflash` 3) Poll `psp_vbflash_status` to check for completion
If userspace reads `psp_vbflash` before writing an image, it's possible that it causes problems that can put the dGPU into an invalid state.
Explicitly check that an image has been written before letting a read succeed.
Cc: stable@vger.kernel.org Fixes: 8424f2ccb3c0 ("drm/amdgpu/psp: Add vbflash sysfs interface support") Reviewed-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Mario Limonciello mario.limonciello@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_psp.c @@ -3538,6 +3538,9 @@ static ssize_t amdgpu_psp_vbflash_read(s void *fw_pri_cpu_addr; int ret;
+ if (adev->psp.vbflash_image_size == 0) + return -EINVAL; + dev_info(adev->dev, "VBIOS flash to PSP started");
ret = amdgpu_bo_create_kernel(adev, adev->psp.vbflash_image_size,