[PATCH] drm/amdgpu: fix deadlock of reservation between cs and gpu reset v2

[Chunming Zhou]

the case could happen when gpu reset:
1. when gpu reset, cs can be continue until sw queue is full, then push job will wait with holding pd reservation.
2. gpu_reset routine will also need pd reservation to restore page table from their shadow.
3. cs is waiting for gpu_reset complete, but gpu reset is waiting for cs releases reservation.

v2: handle amdgpu_cs_submit error path.

Change-Id: I0f66d04b2bef3433035109623c8a5c5992c84202
Signed-off-by: Chunming Zhou <David1.Zhou at amd.com>
Reviewed-by: Christian König <christian.koenig at amd.com>
Reviewed-by: Junwei Zhang <Jerry.Zhang at amd.com>
Reviewed-by: Monk Liu <monk.liu at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
index 26168df..699f5fe 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_cs.c
@@ -1074,6 +1074,7 @@ static int amdgpu_cs_submit(struct amdgpu_cs_parser *p,
 	cs->out.handle = amdgpu_ctx_add_fence(p->ctx, ring, p->fence);
 	job->uf_sequence = cs->out.handle;
 	amdgpu_job_free_resources(job);
+	amdgpu_cs_parser_fini(p, 0, true);
 
 	trace_amdgpu_cs_ioctl(job);
 	amd_sched_entity_push_job(&job->base);
@@ -1129,7 +1130,10 @@ int amdgpu_cs_ioctl(struct drm_device *dev, void *data, struct drm_file *filp)
 		goto out;
 
 	r = amdgpu_cs_submit(&parser, cs);
+	if (r)
+		goto out;
 
+	return 0;
 out:
 	amdgpu_cs_parser_fini(&parser, r, reserved_buffers);
 	return r;
-- 
1.9.1