https://bugs.freedesktop.org/show_bug.cgi?id=107456
Bug ID: 107456 Summary: WARNING: CPU: 11 PID: 1137 at drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu _dm_mst_types.c:88 dm_dp_aux_transfer+0xa5/0xc0 [amdgpu] Product: DRI Version: unspecified Hardware: x86-64 (AMD64) OS: Linux (All) Status: NEW Severity: normal Priority: medium Component: DRM/AMDgpu Assignee: dri-devel@lists.freedesktop.org Reporter: marc@dragonfly.plus.com
Created attachment 140936 --> https://bugs.freedesktop.org/attachment.cgi?id=140936&action=edit dmesg output
I see the following warning during boot with Linux kernel 4.18.0-rc6 & 4.17.10:
root@deepthought:~# dmesg | grep WARN [ 9.346100] WARNING: CPU: 11 PID: 1137 at drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_mst_types.c:88 dm_dp_aux_transfer+0xa5/0xc0 [amdgpu] [ 9.346162] WARNING: CPU: 14 PID: 1139 at drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_mst_types.c:88 dm_dp_aux_transfer+0xa5/0xc0 [amdgpu]
Hardware is Ryzen 7 2700x, Sapphire Technology Radeon RX 480, IIyama ProLite XB2380HS connected via DVI.
It looks like "dm_dp_aux_transfer" is used to setup DisplayPort, using "struct drm_dp_aux_msg — DisplayPort AUX channel transaction". Now, with my hardware I don't have any monitors connected via DisplayPort. Is that relevant?
I patched in a "printk("msg->size = %d\n", msg->size);" and it displays the result twice, which is curious.
# dmesg | grep -i "msg->size" [ 9.469511] msg->size = -5 [ 9.469803] msg->size = -5
Anyway, full "dmesg" attached.