6.6-stable review patch. If anyone has any objections, please let me know.
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From: Christian König christian.koenig@amd.com
[ Upstream commit d7ddcf921e7d0d8ebe82e89635bc9dc26ba9540d ]
Gang submission means that the kernel driver guarantees that multiple submissions are executed on the HW at the same time on different engines.
Background is that those submissions then depend on each other and each can't finish stand alone.
SRIOV now uses world switch to preempt submissions on the engines to allow sharing the HW resources between multiple VFs.
The problem is now that the SRIOV world switch can't know about such inter dependencies and will cause a timeout if it waits for a partially running gang submission.
To conclude SRIOV and gang submissions are fundamentally incompatible at the moment. For now just disable them.
Signed-off-by: Christian König christian.koenig@amd.com Reviewed-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c index 958034bc3b6d5..5b4d7fe148586 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c @@ -286,7 +286,7 @@ static int amdgpu_cs_pass1(struct amdgpu_cs_parser *p, } }
- if (!p->gang_size) { + if (!p->gang_size || (amdgpu_sriov_vf(p->adev) && p->gang_size > 1)) { ret = -EINVAL; goto free_all_kdata; }