This is a note to let you know that I've just added the patch titled drm/vc4: bo: Fix drmm_mutex_init memory hog to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-vc4-bo-fix-drmm_mutex_init-memory-hog.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 295de5c27d7bec7c2dd3853d63eace90d132809f Author: Maxime Ripard <maxime@xxxxxxxxxx> Date: Thu Jan 12 10:12:43 2023 +0100 drm/vc4: bo: Fix drmm_mutex_init memory hog [ Upstream commit 07a2975c65f2be2e22591d795a9c39b00f95fd11 ] Commit 374146cad469 ("drm/vc4: Switch to drmm_mutex_init") converted, among other functions, vc4_create_object() to use drmm_mutex_init(). However, that function is used to allocate a BO, and therefore the mutex needs to be freed much sooner than when the DRM device is removed from the system. For each buffer allocation we thus end up allocating a small structure as part of the DRM-managed mechanism that is never freed, eventually leading us to no longer having any free memory anymore. Let's switch back to mutex_init/mutex_destroy to deal with it properly. Fixes: 374146cad469 ("drm/vc4: Switch to drmm_mutex_init") Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx> Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20230112091243.490799-1-maxime@xxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/vc4/vc4_bo.c b/drivers/gpu/drm/vc4/vc4_bo.c index 231add8b8e12..ab2573525d77 100644 --- a/drivers/gpu/drm/vc4/vc4_bo.c +++ b/drivers/gpu/drm/vc4/vc4_bo.c @@ -179,6 +179,7 @@ static void vc4_bo_destroy(struct vc4_bo *bo) bo->validated_shader = NULL; } + mutex_destroy(&bo->madv_lock); drm_gem_dma_free(&bo->base); } @@ -406,9 +407,7 @@ struct drm_gem_object *vc4_create_object(struct drm_device *dev, size_t size) bo->madv = VC4_MADV_WILLNEED; refcount_set(&bo->usecnt, 0); - ret = drmm_mutex_init(dev, &bo->madv_lock); - if (ret) - return ERR_PTR(ret); + mutex_init(&bo->madv_lock); mutex_lock(&vc4->bo_lock); bo->label = VC4_BO_TYPE_KERNEL;