From: Mario Limonciello <mario.limonciello@xxxxxxx>
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@xxxxxxxxxxxxxxx
Fixes: 8424f2ccb3c0 ("drm/amdgpu/psp: Add vbflash sysfs interface support")
Reviewed-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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,
