* Re: [PATCH] fix: drm/vmwgfx: vmw_user_shader_alloc: fix base object refcount leak on ttm_base_object_init failure
2026-06-26 15:01 [PATCH] fix: drm/vmwgfx: vmw_user_shader_alloc: fix base object refcount leak on ttm_base_object_init failure WenTao Liang
@ 2026-06-28 4:03 ` WenTao Liang
2026-08-07 20:24 ` kernel test robot
2026-08-08 0:58 ` kernel test robot
2 siblings, 0 replies; 4+ messages in thread
From: WenTao Liang @ 2026-06-28 4:03 UTC (permalink / raw)
To: Zack Rusin, dri-devel
Cc: bcm-kernel-feedback-list, Maarten Lankhorst, Maxime Ripard,
Thomas Zimmermann, David Airlie, Simona Vetter, Thomas Hellstrom,
stable, linux-kernel
> 2026年6月26日 23:01，WenTao Liang <vulab@iscas.ac.cn> 写道：
>
> ttm_base_object_init unconditionally acquires a base object reference via
> kref_init. When it fails, the error path in vmw_user_shader_alloc only
> calls vmw_resource_unreference but never calls ttm_base_object_unref to
> release the base object reference, causing a refcount leak.
>
> Add ttm_base_object_unref in the error path to properly release the base
> object reference when ttm_base_object_init fails.
>
> Cc: stable@vger.kernel.org
> Fixes: 0b8762e997df ("drm/ttm, drm/vmwgfx: Move the lock- and object functionality to the vmwgfx driver")
> Signed-off-by: WenTao Liang <vulab@iscas.ac.cn>
> ---
> drivers/gpu/drm/vmwgfx/vmwgfx_shader.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c b/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c
> index eca4e3e97eb4..d82ec43c8901 100644
> --- a/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c
> +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c
> @@ -724,6 +724,7 @@ static int vmw_user_shader_alloc(struct vmw_private *dev_priv,
>
> if (unlikely(ret != 0)) {
> vmw_resource_unreference(&tmp);
> + ttm_base_object_unref(&ushader->base);
> goto out_err;
> }
>
> --
> 2.39.5 (Apple Git-154)
Please ignore this patch. I will resend a proper version after
learning the kernel submission process.
Apologies for the noise.
Best regards,
WenTao Liang
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] fix: drm/vmwgfx: vmw_user_shader_alloc: fix base object refcount leak on ttm_base_object_init failure
2026-06-26 15:01 [PATCH] fix: drm/vmwgfx: vmw_user_shader_alloc: fix base object refcount leak on ttm_base_object_init failure WenTao Liang
2026-06-28 4:03 ` WenTao Liang
@ 2026-08-07 20:24 ` kernel test robot
2026-08-08 0:58 ` kernel test robot
2 siblings, 0 replies; 4+ messages in thread
From: kernel test robot @ 2026-08-07 20:24 UTC (permalink / raw)
To: WenTao Liang, Zack Rusin, dri-devel
Cc: oe-kbuild-all, bcm-kernel-feedback-list, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Simona Vetter,
Thomas Hellstrom, stable, linux-kernel, WenTao Liang
Hi WenTao,
kernel test robot noticed the following build errors:
[auto build test ERROR on drm-misc/drm-misc-next]
[also build test ERROR on daeinki-drm-exynos/exynos-drm-next drm/drm-next drm-i915/for-linux-next drm-i915/for-linux-next-fixes drm-tip/drm-tip linus/master v7.2-rc6 next-20260806]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/WenTao-Liang/fix-drm-vmwgfx-vmw_user_shader_alloc-fix-base-object-refcount-leak-on-ttm_base_object_init-failure/20260807-080356
base: https://gitlab.freedesktop.org/drm/misc/kernel.git drm-misc-next
patch link: https://lore.kernel.org/r/20260626150142.49732-1-vulab%40iscas.ac.cn
patch subject: [PATCH] fix: drm/vmwgfx: vmw_user_shader_alloc: fix base object refcount leak on ttm_base_object_init failure
config: i386-allmodconfig (https://download.01.org/0day-ci/archive/20260808/202608080444.GqlrPBjd-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260808/202608080444.GqlrPBjd-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202608080444.GqlrPBjd-lkp@intel.com/
All errors (new ones prefixed by >>):
drivers/gpu/drm/vmwgfx/vmwgfx_shader.c: In function 'vmw_user_shader_alloc':
>> drivers/gpu/drm/vmwgfx/vmwgfx_shader.c:727:39: error: passing argument 1 of 'ttm_base_object_unref' from incompatible pointer type [-Wincompatible-pointer-types]
727 | ttm_base_object_unref(&ushader->base);
| ^~~~~~~~~~~~~~
| |
| struct ttm_base_object *
In file included from drivers/gpu/drm/vmwgfx/vmwgfx_drv.h:27,
from drivers/gpu/drm/vmwgfx/vmwgfx_shader.c:32:
drivers/gpu/drm/vmwgfx/ttm_object.h:192:60: note: expected 'struct ttm_base_object **' but argument is of type 'struct ttm_base_object *'
192 | extern void ttm_base_object_unref(struct ttm_base_object **p_base);
| ~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~
vim +/ttm_base_object_unref +727 drivers/gpu/drm/vmwgfx/vmwgfx_shader.c
684
685 static int vmw_user_shader_alloc(struct vmw_private *dev_priv,
686 struct vmw_bo *buffer,
687 size_t shader_size,
688 size_t offset,
689 SVGA3dShaderType shader_type,
690 uint8_t num_input_sig,
691 uint8_t num_output_sig,
692 struct ttm_object_file *tfile,
693 u32 *handle)
694 {
695 struct vmw_user_shader *ushader;
696 struct vmw_resource *res, *tmp;
697 int ret;
698
699 ushader = kzalloc_obj(*ushader);
700 if (unlikely(!ushader)) {
701 ret = -ENOMEM;
702 goto out;
703 }
704
705 res = &ushader->shader.res;
706 ushader->base.shareable = false;
707 ushader->base.tfile = NULL;
708
709 /*
710 * From here on, the destructor takes over resource freeing.
711 */
712
713 ret = vmw_gb_shader_init(dev_priv, res, shader_size,
714 offset, shader_type, num_input_sig,
715 num_output_sig, buffer,
716 vmw_user_shader_free);
717 if (unlikely(ret != 0))
718 goto out;
719
720 tmp = vmw_resource_reference(res);
721 ret = ttm_base_object_init(tfile, &ushader->base, false,
722 VMW_RES_SHADER,
723 &vmw_user_shader_base_release);
724
725 if (unlikely(ret != 0)) {
726 vmw_resource_unreference(&tmp);
> 727 ttm_base_object_unref(&ushader->base);
728 goto out_err;
729 }
730
731 if (handle)
732 *handle = ushader->base.handle;
733 out_err:
734 vmw_resource_unreference(&res);
735 out:
736 return ret;
737 }
738
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] fix: drm/vmwgfx: vmw_user_shader_alloc: fix base object refcount leak on ttm_base_object_init failure
2026-06-26 15:01 [PATCH] fix: drm/vmwgfx: vmw_user_shader_alloc: fix base object refcount leak on ttm_base_object_init failure WenTao Liang
2026-06-28 4:03 ` WenTao Liang
2026-08-07 20:24 ` kernel test robot
@ 2026-08-08 0:58 ` kernel test robot
2 siblings, 0 replies; 4+ messages in thread
From: kernel test robot @ 2026-08-08 0:58 UTC (permalink / raw)
To: WenTao Liang, Zack Rusin, dri-devel
Cc: llvm, oe-kbuild-all, bcm-kernel-feedback-list, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Simona Vetter,
Thomas Hellstrom, stable, linux-kernel, WenTao Liang
Hi WenTao,
kernel test robot noticed the following build errors:
[auto build test ERROR on drm-misc/drm-misc-next]
[also build test ERROR on daeinki-drm-exynos/exynos-drm-next drm/drm-next drm-i915/for-linux-next drm-i915/for-linux-next-fixes drm-tip/drm-tip linus/master v7.2-rc6 next-20260807]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/WenTao-Liang/fix-drm-vmwgfx-vmw_user_shader_alloc-fix-base-object-refcount-leak-on-ttm_base_object_init-failure/20260807-080356
base: https://gitlab.freedesktop.org/drm/misc/kernel.git drm-misc-next
patch link: https://lore.kernel.org/r/20260626150142.49732-1-vulab%40iscas.ac.cn
patch subject: [PATCH] fix: drm/vmwgfx: vmw_user_shader_alloc: fix base object refcount leak on ttm_base_object_init failure
config: arm64-randconfig-002-20260807 (https://download.01.org/0day-ci/archive/20260808/202608080849.rqxWdd9U-lkp@intel.com/config)
compiler: clang version 24.0.0git (https://github.com/llvm/llvm-project 12df34b8469b8095359de8c249cb1b2753fadeea)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260808/202608080849.rqxWdd9U-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202608080849.rqxWdd9U-lkp@intel.com/
All errors (new ones prefixed by >>):
>> drivers/gpu/drm/vmwgfx/vmwgfx_shader.c:727:25: error: incompatible pointer types passing 'struct ttm_base_object *' to parameter of type 'struct ttm_base_object **' [-Wincompatible-pointer-types]
727 | ttm_base_object_unref(&ushader->base);
| ^~~~~~~~~~~~~~
drivers/gpu/drm/vmwgfx/ttm_object.h:192:60: note: passing argument to parameter 'p_base' here
192 | extern void ttm_base_object_unref(struct ttm_base_object **p_base);
| ^
1 error generated.
vim +727 drivers/gpu/drm/vmwgfx/vmwgfx_shader.c
684
685 static int vmw_user_shader_alloc(struct vmw_private *dev_priv,
686 struct vmw_bo *buffer,
687 size_t shader_size,
688 size_t offset,
689 SVGA3dShaderType shader_type,
690 uint8_t num_input_sig,
691 uint8_t num_output_sig,
692 struct ttm_object_file *tfile,
693 u32 *handle)
694 {
695 struct vmw_user_shader *ushader;
696 struct vmw_resource *res, *tmp;
697 int ret;
698
699 ushader = kzalloc_obj(*ushader);
700 if (unlikely(!ushader)) {
701 ret = -ENOMEM;
702 goto out;
703 }
704
705 res = &ushader->shader.res;
706 ushader->base.shareable = false;
707 ushader->base.tfile = NULL;
708
709 /*
710 * From here on, the destructor takes over resource freeing.
711 */
712
713 ret = vmw_gb_shader_init(dev_priv, res, shader_size,
714 offset, shader_type, num_input_sig,
715 num_output_sig, buffer,
716 vmw_user_shader_free);
717 if (unlikely(ret != 0))
718 goto out;
719
720 tmp = vmw_resource_reference(res);
721 ret = ttm_base_object_init(tfile, &ushader->base, false,
722 VMW_RES_SHADER,
723 &vmw_user_shader_base_release);
724
725 if (unlikely(ret != 0)) {
726 vmw_resource_unreference(&tmp);
> 727 ttm_base_object_unref(&ushader->base);
728 goto out_err;
729 }
730
731 if (handle)
732 *handle = ushader->base.handle;
733 out_err:
734 vmw_resource_unreference(&res);
735 out:
736 return ret;
737 }
738
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 4+ messages in thread