* [PATCH] drm/amdkfd: fix kgd_mem memory leak when importing dmabuf
@ 2022-07-26 11:15 Lang Yu
2022-07-26 14:03 ` Felix Kuehling
0 siblings, 1 reply; 3+ messages in thread
From: Lang Yu @ 2022-07-26 11:15 UTC (permalink / raw)
To: amd-gfx; +Cc: Felix Kuehling, Lang Yu
The kgd_mem memory allocated in amdgpu_amdkfd_gpuvm_import_dmabuf()
is not freed properly.
Explicitly free it in amdgpu_amdkfd_gpuvm_free_memory_of_gpu()
under condition "mem->bo->kfd_bo != mem".
Suggested-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Lang Yu <Lang.Yu@amd.com>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
index 6bba6961eee7..086bed40cf34 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
@@ -1803,6 +1803,7 @@ int amdgpu_amdkfd_gpuvm_free_memory_of_gpu(
uint64_t *size)
{
struct amdkfd_process_info *process_info = mem->process_info;
+ struct kgd_mem *tmp_mem = mem->bo->kfd_bo;
unsigned long bo_size = mem->bo->tbo.base.size;
struct kfd_mem_attachment *entry, *tmp;
struct bo_vm_reservation_context ctx;
@@ -1895,6 +1896,13 @@ int amdgpu_amdkfd_gpuvm_free_memory_of_gpu(
*/
drm_gem_object_put(&mem->bo->tbo.base);
+ /*
+ * For kgd_mem allocated in amdgpu_amdkfd_gpuvm_import_dmabuf(),
+ * explicitly free it here.
+ */
+ if (mem != tmp_mem)
+ kfree(mem);
+
return ret;
}
--
2.25.1
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] drm/amdkfd: fix kgd_mem memory leak when importing dmabuf
2022-07-26 11:15 [PATCH] drm/amdkfd: fix kgd_mem memory leak when importing dmabuf Lang Yu
@ 2022-07-26 14:03 ` Felix Kuehling
2022-07-27 1:04 ` Lang Yu
0 siblings, 1 reply; 3+ messages in thread
From: Felix Kuehling @ 2022-07-26 14:03 UTC (permalink / raw)
To: Lang Yu, amd-gfx
Am 2022-07-26 um 07:15 schrieb Lang Yu:
> The kgd_mem memory allocated in amdgpu_amdkfd_gpuvm_import_dmabuf()
> is not freed properly.
>
> Explicitly free it in amdgpu_amdkfd_gpuvm_free_memory_of_gpu()
> under condition "mem->bo->kfd_bo != mem".
>
> Suggested-by: Felix Kuehling <Felix.Kuehling@amd.com>
> Signed-off-by: Lang Yu <Lang.Yu@amd.com>
Some suggestions inline to make the code more readable. Other than that,
the patch is
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> index 6bba6961eee7..086bed40cf34 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> @@ -1803,6 +1803,7 @@ int amdgpu_amdkfd_gpuvm_free_memory_of_gpu(
> uint64_t *size)
> {
> struct amdkfd_process_info *process_info = mem->process_info;
> + struct kgd_mem *tmp_mem = mem->bo->kfd_bo;
Right, you need this because using mem after drm_gem_object_put would be
a potential use-after-free. Instead of saving this pointer with some
obscure variable name, you could just save a bool with a more meaningful
name. E.g.:
bool use_release_notifier = (mem->bo->kfd_bo == mem);
This way you have the entire condition in one place, and the variable
name explains the meaning.
> unsigned long bo_size = mem->bo->tbo.base.size;
> struct kfd_mem_attachment *entry, *tmp;
> struct bo_vm_reservation_context ctx;
> @@ -1895,6 +1896,13 @@ int amdgpu_amdkfd_gpuvm_free_memory_of_gpu(
> */
> drm_gem_object_put(&mem->bo->tbo.base);
>
> + /*
> + * For kgd_mem allocated in amdgpu_amdkfd_gpuvm_import_dmabuf(),
> + * explicitly free it here.
> + */
> + if (mem != tmp_mem)
if (!use_release_notifier)
kfree(mem);
Regards,
Felix
> + kfree(mem);
> +
> return ret;
> }
>
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] drm/amdkfd: fix kgd_mem memory leak when importing dmabuf
2022-07-26 14:03 ` Felix Kuehling
@ 2022-07-27 1:04 ` Lang Yu
0 siblings, 0 replies; 3+ messages in thread
From: Lang Yu @ 2022-07-27 1:04 UTC (permalink / raw)
To: Felix Kuehling; +Cc: amd-gfx
On 07/26/ , Felix Kuehling wrote:
> Am 2022-07-26 um 07:15 schrieb Lang Yu:
> > The kgd_mem memory allocated in amdgpu_amdkfd_gpuvm_import_dmabuf()
> > is not freed properly.
> >
> > Explicitly free it in amdgpu_amdkfd_gpuvm_free_memory_of_gpu()
> > under condition "mem->bo->kfd_bo != mem".
> >
> > Suggested-by: Felix Kuehling <Felix.Kuehling@amd.com>
> > Signed-off-by: Lang Yu <Lang.Yu@amd.com>
>
> Some suggestions inline to make the code more readable. Other than that, the
> patch is
>
> Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
>
>
> > ---
> > drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 8 ++++++++
> > 1 file changed, 8 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> > index 6bba6961eee7..086bed40cf34 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> > @@ -1803,6 +1803,7 @@ int amdgpu_amdkfd_gpuvm_free_memory_of_gpu(
> > uint64_t *size)
> > {
> > struct amdkfd_process_info *process_info = mem->process_info;
> > + struct kgd_mem *tmp_mem = mem->bo->kfd_bo;
>
> Right, you need this because using mem after drm_gem_object_put would be a
> potential use-after-free. Instead of saving this pointer with some obscure
> variable name, you could just save a bool with a more meaningful name. E.g.:
>
> bool use_release_notifier = (mem->bo->kfd_bo == mem);
>
> This way you have the entire condition in one place, and the variable name
> explains the meaning.
Got it. Thanks!
Regards,
Lang
>
> > unsigned long bo_size = mem->bo->tbo.base.size;
> > struct kfd_mem_attachment *entry, *tmp;
> > struct bo_vm_reservation_context ctx;
> > @@ -1895,6 +1896,13 @@ int amdgpu_amdkfd_gpuvm_free_memory_of_gpu(
> > */
> > drm_gem_object_put(&mem->bo->tbo.base);
> > + /*
> > + * For kgd_mem allocated in amdgpu_amdkfd_gpuvm_import_dmabuf(),
> > + * explicitly free it here.
> > + */
> > + if (mem != tmp_mem)
>
> if (!use_release_notifier)
> kfree(mem);
>
> Regards,
> Felix
>
>
> > + kfree(mem);
> > +
> > return ret;
> > }
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2022-07-27 1:04 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2022-07-26 11:15 [PATCH] drm/amdkfd: fix kgd_mem memory leak when importing dmabuf Lang Yu
2022-07-26 14:03 ` Felix Kuehling
2022-07-27 1:04 ` Lang Yu
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