The MES scheduler ring has no drm scheduler (no_scheduler = true), so it is skipped by the force-completion loop in amdgpu_device_pre_asic_reset(). It uses a polling fence whose hw value lives in wb (GTT) memory and survives a MODE1 reset, while fence_drv.sync_seq keeps advancing for every packet.
When the reset is triggered because MES itself stopped responding, the timed-out packets advance sync_seq past the last hw fence value MES wrote. After resume the first MES submission polls forever on a seq that is never written back, failing the resume and wedging the box on a second reset: amdgpu: MES ring buffer is full. amdgpu: *ERROR* ring gfx_0.0.0 test failed (-110) amdgpu: resume of IP block <gfx_v11_0> failed -110 amdgpu: GPU reset end with ret = -110 Force complete the MES scheduler ring fences together with the scheduler rings so their hw fence is realigned to sync_seq. v2: cover all XCCs (one scheduler ring each), not just mes.ring[0]. Signed-off-by: Jesse Zhang <[email protected]> --- --- drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c index 520fd59036d5..e2b8253489f3 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c @@ -5036,6 +5036,19 @@ int amdgpu_device_pre_asic_reset(struct amdgpu_device *adev, amdgpu_fence_driver_force_completion(ring, fence); } + /* + * MES scheduler rings have no drm scheduler, so they are missed by the + * loop above. Realign their polling fence too (one per XCC), otherwise the + * first post-reset submission polls forever on a stale seq. sched.ready + * skips KIQ pipes. + */ + for (i = 0; i < AMDGPU_MAX_MES_INST_PIPES; i++) { + struct amdgpu_ring *mes_ring = &adev->mes.ring[i]; + + if (mes_ring->fence_drv.initialized && mes_ring->sched.ready) + amdgpu_fence_driver_force_completion(mes_ring, fence); + } + amdgpu_fence_driver_isr_toggle(adev, false); r = amdgpu_reset_prepare_hwcontext(adev, reset_context); -- 2.49.0
