[PATCH 1/2] drm/amdgpu: Fix sigsev when accessing MMIO on hot unplug.

[Andrey Grodzovsky]

Protect with drm_dev_enter/exit

Signed-off-by: Andrey Grodzovsky <andrey.grodzov...@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c 
b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
index f522b52725e4..4294f17cedcb 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c
@@ -23,6 +23,7 @@
  */
 
 #include <drm/drm_auth.h>
+#include <drm/drm_drv.h>
 #include "amdgpu.h"
 #include "amdgpu_sched.h"
 #include "amdgpu_ras.h"
@@ -339,7 +340,7 @@ static void amdgpu_ctx_fini(struct kref *ref)
 {
        struct amdgpu_ctx *ctx = container_of(ref, struct amdgpu_ctx, refcount);
        struct amdgpu_device *adev = ctx->adev;
-       unsigned i, j;
+       unsigned i, j, idx;
 
        if (!adev)
                return;
@@ -350,7 +351,12 @@ static void amdgpu_ctx_fini(struct kref *ref)
                        ctx->entities[i][j] = NULL;
                }
        }
-       amdgpu_ctx_set_stable_pstate(ctx, AMDGPU_CTX_STABLE_PSTATE_NONE);
+
+       if (drm_dev_enter(&adev->ddev, &idx)) {
+               amdgpu_ctx_set_stable_pstate(ctx, 
AMDGPU_CTX_STABLE_PSTATE_NONE);
+               drm_dev_exit(idx);
+       }
+
        kfree(ctx);
 }
 
-- 
2.25.1