6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Wayne Lin Wayne.Lin@amd.com
commit 396dc51b3b7ea524bf8061f478332d0039e96d5d upstream.
[Why & How] "Request length != reply length" is expected behavior defined in spec. It's not an invalid reply. Besides, replied data handling logic is not designed to be written in amdgpu_dm_process_dmub_aux_transfer_sync(). Remove the incorrectly handling section.
Fixes: ead08b95fa50 ("drm/amd/display: Fix race condition in DPIA AUX transfer") Cc: Mario Limonciello mario.limonciello@amd.com Cc: Alex Deucher alexander.deucher@amd.com Reviewed-by: Ray Wu ray.wu@amd.com Signed-off-by: Wayne Lin Wayne.Lin@amd.com Signed-off-by: Ray Wu ray.wu@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com (cherry picked from commit 81b5c6fa62af62fe89ae9576f41aae37830b94cb) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 12 +----------- 1 file changed, 1 insertion(+), 11 deletions(-)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -12547,19 +12547,9 @@ int amdgpu_dm_process_dmub_aux_transfer_ payload->reply[0] = (adev->dm.dmub_notify->aux_reply.command >> 4) & 0xF;
if (!payload->write && p_notify->aux_reply.length && - (payload->reply[0] == AUX_TRANSACTION_REPLY_AUX_ACK)) { - - if (payload->length != p_notify->aux_reply.length) { - DRM_WARN("invalid read length %d from DPIA AUX 0x%x(%d)!\n", - p_notify->aux_reply.length, - payload->address, payload->length); - *operation_result = AUX_RET_ERROR_INVALID_REPLY; - goto out; - } - + (payload->reply[0] == AUX_TRANSACTION_REPLY_AUX_ACK)) memcpy(payload->data, p_notify->aux_reply.data, p_notify->aux_reply.length); - }
/* success */ ret = p_notify->aux_reply.length;