[PATCH 0/3] drm/msm/a6xx: devcore dump fixes

[PATCH 0/3] drm/msm/a6xx: devcore dump fixes

[Rob Clark]

From: Rob Clark <robdclark@chromium.org>

First patch fixes a recently introduced memory corruption, the remaining
two are cleanups.

Rob Clark (3):
  drm/msm/a6xx: Fix kvzalloc vs state_kcalloc usage
  drm/msm/a6xx: Skip snapshotting unused GMU buffers
  drm/msm/a6xx: Remove state objects from list before freeing

 drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c | 18 ++++++++++++++++--
 drivers/gpu/drm/msm/adreno/adreno_gpu.c     |  7 ++++++-
 2 files changed, 22 insertions(+), 3 deletions(-)

-- 
2.37.3

[PATCH 1/3] drm/msm/a6xx: Fix kvzalloc vs state_kcalloc usage

[Rob Clark]

From: Rob Clark <robdclark@chromium.org>

adreno_show_object() is a trap!  It will re-allocate the pointer it is
passed on first call, when the data is ascii85 encoded, using kvmalloc/
kvfree().  Which means the data *passed* to it must be kvmalloc'd, ie.
we cannot use the state_kcalloc() helper.

This partially reverts
ec8f1813bf8d ("drm/msm/a6xx: Replace kcalloc() with kvzalloc()"), but
fix the missing kvfree() to fix the memory leak that was present
previously.  And adds a warning comment.

Fixes: ec8f1813bf8d ("drm/msm/a6xx: Replace kcalloc() with kvzalloc()")
Closes: https://gitlab.freedesktop.org/drm/msm/-/issues/20
Signed-off-by: Rob Clark <robdclark@chromium.org>
---
 drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c | 11 ++++++++++-
 drivers/gpu/drm/msm/adreno/adreno_gpu.c     |  7 ++++++-
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c
index 3c112a6cc8a2..730355f9e2d4 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c
@@ -819,7 +819,7 @@ static struct msm_gpu_state_bo *a6xx_snapshot_gmu_bo(
 
 	snapshot->iova = bo->iova;
 	snapshot->size = bo->size;
-	snapshot->data = state_kcalloc(a6xx_state, 1, snapshot->size);
+	snapshot->data = kvzalloc(snapshot->size, GFP_KERNEL);
 	if (!snapshot->data)
 		return NULL;
 
@@ -1034,6 +1034,15 @@ static void a6xx_gpu_state_destroy(struct kref *kref)
 	struct a6xx_gpu_state *a6xx_state = container_of(state,
 			struct a6xx_gpu_state, base);
 
+	if (a6xx_state->gmu_log)
+		kvfree(a6xx_state->gmu_log->data);
+
+	if (a6xx_state->gmu_hfi)
+		kvfree(a6xx_state->gmu_hfi->data);
+
+	if (a6xx_state->gmu_debug)
+		kvfree(a6xx_state->gmu_debug->data);
+
 	list_for_each_entry_safe(obj, tmp, &a6xx_state->objs, node)
 		kvfree(obj);
 
diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
index 382fb7f9e497..5a0e8491cd3a 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
@@ -729,7 +729,12 @@ static char *adreno_gpu_ascii85_encode(u32 *src, size_t len)
 	return buf;
 }
 
-/* len is expected to be in bytes */
+/* len is expected to be in bytes
+ *
+ * WARNING: *ptr should be allocated with kvmalloc or friends.  It can be free'd
+ * with kvfree() and replaced with a newly kvmalloc'd buffer on the first call
+ * when the unencoded raw data is encoded
+ */
 void adreno_show_object(struct drm_printer *p, void **ptr, int len,
 		bool *encoded)
 {
-- 
2.37.3

[PATCH 2/3] drm/msm/a6xx: Skip snapshotting unused GMU buffers

[Rob Clark]

From: Rob Clark <robdclark@chromium.org>

Some buffers are unused on certain sub-generations of a6xx.  So just
skip them.

Signed-off-by: Rob Clark <robdclark@chromium.org>
---
 drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c
index 730355f9e2d4..b0124d0f286c 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c
@@ -813,6 +813,9 @@ static struct msm_gpu_state_bo *a6xx_snapshot_gmu_bo(
 {
 	struct msm_gpu_state_bo *snapshot;
 
+	if (!bo->size)
+		return NULL;
+
 	snapshot = state_kcalloc(a6xx_state, 1, sizeof(*snapshot));
 	if (!snapshot)
 		return NULL;
-- 
2.37.3

[PATCH 3/3] drm/msm/a6xx: Remove state objects from list before freeing

[Rob Clark]

From: Rob Clark <robdclark@chromium.org>

Technically it worked as it was before, only because it was using the
_safe version of the iterator.  But it is sloppy practice to leave
dangling pointers.

Signed-off-by: Rob Clark <robdclark@chromium.org>
---
 drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c
index b0124d0f286c..a5c3d1ed255a 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c
@@ -1046,8 +1046,10 @@ static void a6xx_gpu_state_destroy(struct kref *kref)
 	if (a6xx_state->gmu_debug)
 		kvfree(a6xx_state->gmu_debug->data);
 
-	list_for_each_entry_safe(obj, tmp, &a6xx_state->objs, node)
+	list_for_each_entry_safe(obj, tmp, &a6xx_state->objs, node) {
+		list_del(&obj->node);
 		kvfree(obj);
+	}
 
 	adreno_gpu_state_destroy(state);
 	kfree(a6xx_state);
-- 
2.37.3

Re: [Freedreno] [PATCH 0/3] drm/msm/a6xx: devcore dump fixes

[Chia-I Wu]

On Thu, Oct 13, 2022 at 3:55 PM Rob Clark <robdclark@gmail.com> wrote:
>
> From: Rob Clark <robdclark@chromium.org>
>
> First patch fixes a recently introduced memory corruption, the remaining
> two are cleanups.
Series is

Reviewed-by: Chia-I Wu <olvaffe@gmail.com>

> Rob Clark (3):
>   drm/msm/a6xx: Fix kvzalloc vs state_kcalloc usage
>   drm/msm/a6xx: Skip snapshotting unused GMU buffers
>   drm/msm/a6xx: Remove state objects from list before freeing
>
>  drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c | 18 ++++++++++++++++--
>  drivers/gpu/drm/msm/adreno/adreno_gpu.c     |  7 ++++++-
>  2 files changed, 22 insertions(+), 3 deletions(-)
>
> --
> 2.37.3
>

Re: [PATCH 0/3] drm/msm/a6xx: devcore dump fixes

[Akhil P Oommen]

On 10/14/2022 4:25 AM, Rob Clark wrote:
> From: Rob Clark <robdclark@chromium.org>
>
> First patch fixes a recently introduced memory corruption, the remaining
> two are cleanups.
>
> Rob Clark (3):
>    drm/msm/a6xx: Fix kvzalloc vs state_kcalloc usage
>    drm/msm/a6xx: Skip snapshotting unused GMU buffers
>    drm/msm/a6xx: Remove state objects from list before freeing
>
>   drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c | 18 ++++++++++++++++--
>   drivers/gpu/drm/msm/adreno/adreno_gpu.c     |  7 ++++++-
>   2 files changed, 22 insertions(+), 3 deletions(-)
For the entire series:

Reviewed-by: Akhil P Oommen <quic_akhilpo@quicinc.com>


-Akhil