2022-10-13 23:49:56

by Rob Clark

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

From: Rob Clark <[email protected]>

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


2022-10-14 00:07:53

by Rob Clark

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

From: Rob Clark <[email protected]>

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 <[email protected]>
---
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

2022-10-14 00:53:29

by Chia-I Wu

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

On Thu, Oct 13, 2022 at 3:55 PM Rob Clark <[email protected]> wrote:
>
> From: Rob Clark <[email protected]>
>
> First patch fixes a recently introduced memory corruption, the remaining
> two are cleanups.
Series is

Reviewed-by: Chia-I Wu <[email protected]>

> 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
>

2022-10-14 07:17:42

by Akhil P Oommen

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

On 10/14/2022 4:25 AM, Rob Clark wrote:
> From: Rob Clark <[email protected]>
>
> 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 <[email protected]>


-Akhil