From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7E4C7CD4855 for ; Tue, 12 May 2026 06:59:43 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D1D3710E98F; Tue, 12 May 2026 06:59:42 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=collabora.com header.i=@collabora.com header.b="ozso+RVb"; dkim-atps=neutral Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) by gabe.freedesktop.org (Postfix) with ESMTPS id 1B5E510E97E; Tue, 12 May 2026 06:59:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1778569179; bh=J+NY9aw302p6PN11QMd9bND2sUR0QuHE8mhg4lF7Css=; h=From:Date:Subject:To:Cc:From; b=ozso+RVbBP17gfGWovL+21GYPpDekhdTu/DH8w3NCLG3JIWF4gEALgsR6gDZBUEtY QLbfzPEEoQ8rzB0HhWz1Hk/ntkKijkqqBIwkG4S8eg8yVWs8cb6UpRdIIucjIJDFRf f/EIFq9bUnqJFWEHerutxGmC3hlnE8zLTto0BS4z+PFbxbxp6B0Jl308NbnnwBr85Y W5m/MV3rmScAKAHKyAxOy487D2JmrMRxnUCib6JjJHMkO5XkDryQoHm/KrXGv3nmCM nRBQWm4LYSxydfn8vpeIfYbVHLlob/q4Q5/5hCKovkqmRg48vqSnNkvkTxzuwm4j2g TattjjU3VGVrg== Received: from [192.168.1.38] (unknown [100.64.0.11]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bbrezillon) by bali.collaboradmins.com (Postfix) with ESMTPSA id F2B9517E0615; Tue, 12 May 2026 08:59:38 +0200 (CEST) From: Boris Brezillon Date: Tue, 12 May 2026 08:59:17 +0200 Subject: [PATCH v3] drm/gem: Make the GEM LRU lock part of drm_device MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260512-panthor-shrinker-fixes-v3-1-3bf066259471@collabora.com> X-B4-Tracking: v=1; b=H4sIAAAAAAAC/4WQwQ6CMBBEf4X0bE1bLAVO/ofxUNpFGoHqFonG+ O+ucjEmxuPsZN5O5s4SYIDE6uzOEOaQQhxJ5KuMuc6OB+DBk2ZKqEJoUfCTHacuIk8dhvEIyNt whcR16WS70a51G8kofEJ4G5Td7Ul3IU0Rb+8/s3xd/yJnyQUHY5TUqvBQFVsX+942Ee3axYG9s LP6RJU/UYpQeeV8Y7w2xlXfqMdSGeF8oQmmpTdrbAJO/hCmOmsUeCHBWJ97CjyeQS0WTTsBAAA = X-Change-ID: 20260506-panthor-shrinker-fixes-58c1f45cfc41 To: Steven Price , Liviu Dudau , Boris Brezillon Cc: Dmitry Osipenko , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Akash Goel , Chia-I Wu , Rob Clark , Dmitry Baryshkov , Abhinav Kumar , Jessica Zhang , Sean Paul , Marijn Suijten , linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Rob Clark X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1778569178; l=19580; i=boris.brezillon@collabora.com; s=20260429; h=from:subject:message-id; bh=J+NY9aw302p6PN11QMd9bND2sUR0QuHE8mhg4lF7Css=; b=Tv311XGXWzgBQYA4ZdW8NJfXHhI/4UUFmbVxpjcZzd3ZEOYMuuGcnbhzosWwWJm9j9yEuFIQw nYvLDTAonlwCy7PJq5fEoCmcXDDa9j31FNRN7lZyX68gK0thz83paWe X-Developer-Key: i=boris.brezillon@collabora.com; a=ed25519; pk=eN+ORdOgQY7d5U+0kA8h5bf67XdD8bhKbjD/TCHexSY= X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Recently, a few races have been discovered in the GEM LRU logic, all of them caused by the fact the LRU lock is accessed through gem->lru->lock, and that very same lock also protects changes to gem->lru, leading to situations where gem->lru needs to first be accessed without the lock held, to then get the lru to access the lock through and finally take the lock and do the expected operation. Currently, the only driver making use of this API (MSM) declares a device-wide lock, and the user we're about to add (panthor) will do the same. There's no evidence that we will ever have a driver that wants different pools of LRUs protected by different locks under the same drm_device. So we're better off moving this lock to drm_device and always locking it through obj->dev->gem_lru_mutex, or directly through dev->gem_lru_mutex. If anyone ever needs more fine-grained locking, this can be revisited to pass some drm_gem_lru_pool object representing the pool of LRUs under a specific lock, but for now, the per-device lock seems to be enough. Fixes: e7c2af13f811 ("drm/gem: Add LRU/shrinker helper") Reported-by: Chia-I Wu Closes: https://gitlab.freedesktop.org/panfrost/linux/-/work_items/86 Reviewed-by: Rob Clark Reviewed-by: Liviu Dudau Signed-off-by: Boris Brezillon --- As reported by Chia-I [1], a race exists between drm_gem_lru_remove() and drm_gem_lru_scan(), causing a UAF on a stack-allocated object. This new version only keeps the last patch of the series that addresses the problem more generically by moving the LRU lock to the drm_device object. [1]https://gitlab.freedesktop.org/panfrost/linux/-/work_items/86 --- Changes in v3: - Only keep patch 4 and flag it for backport - Rebase on drm-misc-fixes - Link to v2: https://lore.kernel.org/r/20260508-panthor-shrinker-fixes-v2-0-39cdb7d577c9@collabora.com Changes in v2: - Collect R-b - Drop a useless obj->lru != NULL check in drm_gem_lru_scan() - Fix another race introduced in patch 2 - Document why the lru != NULL check done without the lru lock held in drm_gem_lru_remove() is safe - Add a patch to sanitize the GEM LRU locking: lock is now part of drm_device, meaning we don't have this chicken/egg problem where the lock that needs to acquired is under gem->lru->lock, and gem->lru is also supposed to be accessed with the lru->lock held - Fix typos in commit messages and comments - Link to v1: https://lore.kernel.org/r/20260506-panthor-shrinker-fixes-v1-0-e7721526de96@collabora.com --- drivers/gpu/drm/drm_drv.c | 2 ++ drivers/gpu/drm/drm_gem.c | 34 +++++++++++++++------------------- drivers/gpu/drm/msm/msm_drv.c | 11 +++++------ drivers/gpu/drm/msm/msm_drv.h | 7 ------- drivers/gpu/drm/msm/msm_gem.c | 32 ++++++++++++++++---------------- drivers/gpu/drm/msm/msm_gem_shrinker.c | 4 ++-- drivers/gpu/drm/msm/msm_gem_submit.c | 6 +++--- drivers/gpu/drm/msm/msm_gem_vma.c | 12 ++++++------ drivers/gpu/drm/msm/msm_ringbuffer.c | 6 +++--- include/drm/drm_device.h | 7 +++++++ include/drm/drm_gem.h | 20 +++++++++----------- 11 files changed, 68 insertions(+), 73 deletions(-) diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c index 985c283cf59f..675675480da4 100644 --- a/drivers/gpu/drm/drm_drv.c +++ b/drivers/gpu/drm/drm_drv.c @@ -697,6 +697,7 @@ static void drm_dev_init_release(struct drm_device *dev, void *res) mutex_destroy(&dev->master_mutex); mutex_destroy(&dev->clientlist_mutex); mutex_destroy(&dev->filelist_mutex); + mutex_destroy(&dev->gem_lru_mutex); } static int drm_dev_init(struct drm_device *dev, @@ -738,6 +739,7 @@ static int drm_dev_init(struct drm_device *dev, INIT_LIST_HEAD(&dev->vblank_event_list); spin_lock_init(&dev->event_lock); + mutex_init(&dev->gem_lru_mutex); mutex_init(&dev->filelist_mutex); mutex_init(&dev->clientlist_mutex); mutex_init(&dev->master_mutex); diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index d6424267260b..2b1ac2b02b14 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -1544,9 +1544,8 @@ EXPORT_SYMBOL(drm_gem_unlock_reservations); * @lock: The lock protecting the LRU */ void -drm_gem_lru_init(struct drm_gem_lru *lru, struct mutex *lock) +drm_gem_lru_init(struct drm_gem_lru *lru) { - lru->lock = lock; lru->count = 0; INIT_LIST_HEAD(&lru->list); } @@ -1571,14 +1570,10 @@ drm_gem_lru_remove_locked(struct drm_gem_object *obj) void drm_gem_lru_remove(struct drm_gem_object *obj) { - struct drm_gem_lru *lru = obj->lru; - - if (!lru) - return; - - mutex_lock(lru->lock); - drm_gem_lru_remove_locked(obj); - mutex_unlock(lru->lock); + mutex_lock(&obj->dev->gem_lru_mutex); + if (obj->lru) + drm_gem_lru_remove_locked(obj); + mutex_unlock(&obj->dev->gem_lru_mutex); } EXPORT_SYMBOL(drm_gem_lru_remove); @@ -1593,7 +1588,7 @@ EXPORT_SYMBOL(drm_gem_lru_remove); void drm_gem_lru_move_tail_locked(struct drm_gem_lru *lru, struct drm_gem_object *obj) { - lockdep_assert_held_once(lru->lock); + lockdep_assert_held_once(&obj->dev->gem_lru_mutex); if (obj->lru) drm_gem_lru_remove_locked(obj); @@ -1617,9 +1612,9 @@ EXPORT_SYMBOL(drm_gem_lru_move_tail_locked); void drm_gem_lru_move_tail(struct drm_gem_lru *lru, struct drm_gem_object *obj) { - mutex_lock(lru->lock); + mutex_lock(&obj->dev->gem_lru_mutex); drm_gem_lru_move_tail_locked(lru, obj); - mutex_unlock(lru->lock); + mutex_unlock(&obj->dev->gem_lru_mutex); } EXPORT_SYMBOL(drm_gem_lru_move_tail); @@ -1640,7 +1635,8 @@ EXPORT_SYMBOL(drm_gem_lru_move_tail); * @ticket: Optional ww_acquire_ctx context to use for locking */ unsigned long -drm_gem_lru_scan(struct drm_gem_lru *lru, +drm_gem_lru_scan(struct drm_device *dev, + struct drm_gem_lru *lru, unsigned int nr_to_scan, unsigned long *remaining, bool (*shrink)(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket), @@ -1650,9 +1646,9 @@ drm_gem_lru_scan(struct drm_gem_lru *lru, struct drm_gem_object *obj; unsigned freed = 0; - drm_gem_lru_init(&still_in_lru, lru->lock); + drm_gem_lru_init(&still_in_lru); - mutex_lock(lru->lock); + mutex_lock(&dev->gem_lru_mutex); while (freed < nr_to_scan) { obj = list_first_entry_or_null(&lru->list, typeof(*obj), lru_node); @@ -1675,7 +1671,7 @@ drm_gem_lru_scan(struct drm_gem_lru *lru, * rest of the loop body, to reduce contention with other * code paths that need the LRU lock */ - mutex_unlock(lru->lock); + mutex_unlock(&dev->gem_lru_mutex); if (ticket) ww_acquire_init(ticket, &reservation_ww_class); @@ -1709,7 +1705,7 @@ drm_gem_lru_scan(struct drm_gem_lru *lru, tail: drm_gem_object_put(obj); - mutex_lock(lru->lock); + mutex_lock(&dev->gem_lru_mutex); } /* @@ -1721,7 +1717,7 @@ drm_gem_lru_scan(struct drm_gem_lru *lru, list_splice_tail(&still_in_lru.list, &lru->list); lru->count += still_in_lru.count; - mutex_unlock(lru->lock); + mutex_unlock(&dev->gem_lru_mutex); return freed; } diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c index 195f40e331e5..cc2bcd14b1c2 100644 --- a/drivers/gpu/drm/msm/msm_drv.c +++ b/drivers/gpu/drm/msm/msm_drv.c @@ -128,11 +128,10 @@ static int msm_drm_init(struct device *dev, const struct drm_driver *drv, /* * Initialize the LRUs: */ - mutex_init(&priv->lru.lock); - drm_gem_lru_init(&priv->lru.unbacked, &priv->lru.lock); - drm_gem_lru_init(&priv->lru.pinned, &priv->lru.lock); - drm_gem_lru_init(&priv->lru.willneed, &priv->lru.lock); - drm_gem_lru_init(&priv->lru.dontneed, &priv->lru.lock); + drm_gem_lru_init(&priv->lru.unbacked); + drm_gem_lru_init(&priv->lru.pinned); + drm_gem_lru_init(&priv->lru.willneed); + drm_gem_lru_init(&priv->lru.dontneed); /* Initialize stall-on-fault */ spin_lock_init(&priv->fault_stall_lock); @@ -140,7 +139,7 @@ static int msm_drm_init(struct device *dev, const struct drm_driver *drv, /* Teach lockdep about lock ordering wrt. shrinker: */ fs_reclaim_acquire(GFP_KERNEL); - might_lock(&priv->lru.lock); + might_lock(&ddev->gem_lru_mutex); fs_reclaim_release(GFP_KERNEL); if (priv->kms_init) { diff --git a/drivers/gpu/drm/msm/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h index 6d847d593f1a..617b3c4b42c0 100644 --- a/drivers/gpu/drm/msm/msm_drv.h +++ b/drivers/gpu/drm/msm/msm_drv.h @@ -150,13 +150,6 @@ struct msm_drm_private { * DONTNEED state (ie. can be purged) */ struct drm_gem_lru dontneed; - - /** - * lock: - * - * Protects manipulation of all of the LRUs. - */ - struct mutex lock; } lru; struct notifier_block vmap_notifier; diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c index 2cb3ab04f125..070f5fc4bc17 100644 --- a/drivers/gpu/drm/msm/msm_gem.c +++ b/drivers/gpu/drm/msm/msm_gem.c @@ -177,11 +177,11 @@ static void update_lru_locked(struct drm_gem_object *obj) static void update_lru(struct drm_gem_object *obj) { - struct msm_drm_private *priv = obj->dev->dev_private; + struct drm_device *dev = obj->dev; - mutex_lock(&priv->lru.lock); + mutex_lock(&dev->gem_lru_mutex); update_lru_locked(obj); - mutex_unlock(&priv->lru.lock); + mutex_unlock(&dev->gem_lru_mutex); } static struct page **get_pages(struct drm_gem_object *obj) @@ -292,11 +292,11 @@ void msm_gem_pin_obj_locked(struct drm_gem_object *obj) static void pin_obj_locked(struct drm_gem_object *obj) { - struct msm_drm_private *priv = obj->dev->dev_private; + struct drm_device *dev = obj->dev; - mutex_lock(&priv->lru.lock); + mutex_lock(&dev->gem_lru_mutex); msm_gem_pin_obj_locked(obj); - mutex_unlock(&priv->lru.lock); + mutex_unlock(&dev->gem_lru_mutex); } struct page **msm_gem_pin_pages_locked(struct drm_gem_object *obj) @@ -487,16 +487,16 @@ int msm_gem_pin_vma_locked(struct drm_gem_object *obj, struct drm_gpuva *vma) void msm_gem_unpin_locked(struct drm_gem_object *obj) { - struct msm_drm_private *priv = obj->dev->dev_private; + struct drm_device *dev = obj->dev; struct msm_gem_object *msm_obj = to_msm_bo(obj); msm_gem_assert_locked(obj); - mutex_lock(&priv->lru.lock); + mutex_lock(&dev->gem_lru_mutex); msm_obj->pin_count--; GEM_WARN_ON(msm_obj->pin_count < 0); update_lru_locked(obj); - mutex_unlock(&priv->lru.lock); + mutex_unlock(&dev->gem_lru_mutex); } /* Special unpin path for use in fence-signaling path, avoiding the need @@ -507,10 +507,10 @@ void msm_gem_unpin_locked(struct drm_gem_object *obj) */ void msm_gem_unpin_active(struct drm_gem_object *obj) { - struct msm_drm_private *priv = obj->dev->dev_private; + struct drm_device *dev = obj->dev; struct msm_gem_object *msm_obj = to_msm_bo(obj); - GEM_WARN_ON(!mutex_is_locked(&priv->lru.lock)); + GEM_WARN_ON(!mutex_is_locked(&dev->gem_lru_mutex)); msm_obj->pin_count--; GEM_WARN_ON(msm_obj->pin_count < 0); @@ -797,12 +797,12 @@ void msm_gem_put_vaddr(struct drm_gem_object *obj) */ int msm_gem_madvise(struct drm_gem_object *obj, unsigned madv) { - struct msm_drm_private *priv = obj->dev->dev_private; + struct drm_device *dev = obj->dev; struct msm_gem_object *msm_obj = to_msm_bo(obj); msm_gem_lock(obj); - mutex_lock(&priv->lru.lock); + mutex_lock(&dev->gem_lru_mutex); if (msm_obj->madv != __MSM_MADV_PURGED) msm_obj->madv = madv; @@ -814,7 +814,7 @@ int msm_gem_madvise(struct drm_gem_object *obj, unsigned madv) */ update_lru_locked(obj); - mutex_unlock(&priv->lru.lock); + mutex_unlock(&dev->gem_lru_mutex); msm_gem_unlock(obj); @@ -839,10 +839,10 @@ void msm_gem_purge(struct drm_gem_object *obj) put_pages(obj); - mutex_lock(&priv->lru.lock); + mutex_lock(&dev->gem_lru_mutex); /* A one-way transition: */ msm_obj->madv = __MSM_MADV_PURGED; - mutex_unlock(&priv->lru.lock); + mutex_unlock(&dev->gem_lru_mutex); drm_gem_free_mmap_offset(obj); diff --git a/drivers/gpu/drm/msm/msm_gem_shrinker.c b/drivers/gpu/drm/msm/msm_gem_shrinker.c index 31fa51a44f86..c07af9602fee 100644 --- a/drivers/gpu/drm/msm/msm_gem_shrinker.c +++ b/drivers/gpu/drm/msm/msm_gem_shrinker.c @@ -186,7 +186,7 @@ msm_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc) if (!stages[i].cond) continue; stages[i].freed = - drm_gem_lru_scan(stages[i].lru, nr, + drm_gem_lru_scan(priv->dev, stages[i].lru, nr, &stages[i].remaining, stages[i].shrink, &ticket); @@ -255,7 +255,7 @@ msm_gem_shrinker_vmap(struct notifier_block *nb, unsigned long event, void *ptr) unsigned long remaining = 0; for (idx = 0; lrus[idx] && unmapped < vmap_shrink_limit; idx++) { - unmapped += drm_gem_lru_scan(lrus[idx], + unmapped += drm_gem_lru_scan(priv->dev, lrus[idx], vmap_shrink_limit - unmapped, &remaining, vmap_shrink, diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c index 26ea8a28be47..3c6bc90c3d48 100644 --- a/drivers/gpu/drm/msm/msm_gem_submit.c +++ b/drivers/gpu/drm/msm/msm_gem_submit.c @@ -352,7 +352,7 @@ static int submit_fence_sync(struct msm_gem_submit *submit) static int submit_pin_objects(struct msm_gem_submit *submit) { - struct msm_drm_private *priv = submit->dev->dev_private; + struct drm_device *dev = submit->dev; int i, ret = 0; for (i = 0; i < submit->nr_bos; i++) { @@ -381,11 +381,11 @@ static int submit_pin_objects(struct msm_gem_submit *submit) * get_pages() which could trigger reclaim.. and if we held the LRU lock * could trigger deadlock with the shrinker). */ - mutex_lock(&priv->lru.lock); + mutex_lock(&dev->gem_lru_mutex); for (i = 0; i < submit->nr_bos; i++) { msm_gem_pin_obj_locked(submit->bos[i].obj); } - mutex_unlock(&priv->lru.lock); + mutex_unlock(&dev->gem_lru_mutex); submit->bos_pinned = true; diff --git a/drivers/gpu/drm/msm/msm_gem_vma.c b/drivers/gpu/drm/msm/msm_gem_vma.c index 1a952b171ed7..c4cfe036066b 100644 --- a/drivers/gpu/drm/msm/msm_gem_vma.c +++ b/drivers/gpu/drm/msm/msm_gem_vma.c @@ -702,7 +702,7 @@ static struct dma_fence * msm_vma_job_run(struct drm_sched_job *_job) { struct msm_vm_bind_job *job = to_msm_vm_bind_job(_job); - struct msm_drm_private *priv = job->vm->drm->dev_private; + struct drm_device *dev = job->vm->drm; struct msm_gem_vm *vm = to_msm_vm(job->vm); struct drm_gem_object *obj; int ret = vm->unusable ? -EINVAL : 0; @@ -745,13 +745,13 @@ msm_vma_job_run(struct drm_sched_job *_job) if (ret) msm_gem_vm_unusable(job->vm); - mutex_lock(&priv->lru.lock); + mutex_lock(&dev->gem_lru_mutex); job_foreach_bo (obj, job) { msm_gem_unpin_active(obj); } - mutex_unlock(&priv->lru.lock); + mutex_unlock(&dev->gem_lru_mutex); /* VM_BIND ops are synchronous, so no fence to wait on: */ return NULL; @@ -1305,7 +1305,7 @@ vm_bind_job_pin_objects(struct msm_vm_bind_job *job) return PTR_ERR(pages); } - struct msm_drm_private *priv = job->vm->drm->dev_private; + struct drm_device *dev = job->vm->drm; /* * A second loop while holding the LRU lock (a) avoids acquiring/dropping @@ -1314,10 +1314,10 @@ vm_bind_job_pin_objects(struct msm_vm_bind_job *job) * get_pages() which could trigger reclaim.. and if we held the LRU lock * could trigger deadlock with the shrinker). */ - mutex_lock(&priv->lru.lock); + mutex_lock(&dev->gem_lru_mutex); job_foreach_bo (obj, job) msm_gem_pin_obj_locked(obj); - mutex_unlock(&priv->lru.lock); + mutex_unlock(&dev->gem_lru_mutex); job->bos_pinned = true; diff --git a/drivers/gpu/drm/msm/msm_ringbuffer.c b/drivers/gpu/drm/msm/msm_ringbuffer.c index 30ddb5351e98..2d6b930b766e 100644 --- a/drivers/gpu/drm/msm/msm_ringbuffer.c +++ b/drivers/gpu/drm/msm/msm_ringbuffer.c @@ -16,13 +16,13 @@ static struct dma_fence *msm_job_run(struct drm_sched_job *job) struct msm_gem_submit *submit = to_msm_submit(job); struct msm_fence_context *fctx = submit->ring->fctx; struct msm_gpu *gpu = submit->gpu; - struct msm_drm_private *priv = gpu->dev->dev_private; + struct drm_device *dev = gpu->dev; unsigned nr_cmds = submit->nr_cmds; int i; msm_fence_init(submit->hw_fence, fctx); - mutex_lock(&priv->lru.lock); + mutex_lock(&dev->gem_lru_mutex); for (i = 0; i < submit->nr_bos; i++) { struct drm_gem_object *obj = submit->bos[i].obj; @@ -32,7 +32,7 @@ static struct dma_fence *msm_job_run(struct drm_sched_job *job) submit->bos_pinned = false; - mutex_unlock(&priv->lru.lock); + mutex_unlock(&dev->gem_lru_mutex); /* TODO move submit path over to using a per-ring lock.. */ mutex_lock(&gpu->lock); diff --git a/include/drm/drm_device.h b/include/drm/drm_device.h index bc78fb77cc27..768a8dae83c5 100644 --- a/include/drm/drm_device.h +++ b/include/drm/drm_device.h @@ -375,6 +375,13 @@ struct drm_device { * Root directory for debugfs files. */ struct dentry *debugfs_root; + + /** + * @gem_lru_mutex: + * + * Lock protecting movement of GEM objects between LRUs. + */ + struct mutex gem_lru_mutex; }; void drm_dev_set_dma_dev(struct drm_device *dev, struct device *dma_dev); diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h index 86f5846154f7..8a704f6a65c1 100644 --- a/include/drm/drm_gem.h +++ b/include/drm/drm_gem.h @@ -245,17 +245,11 @@ struct drm_gem_object_funcs { * for lockless &shrinker.count_objects, and provides * &drm_gem_lru_scan for driver's &shrinker.scan_objects * implementation. + * + * Any access to this kind of object must be done with + * drm_device::gem_lru_mutex held. */ struct drm_gem_lru { - /** - * @lock: - * - * Lock protecting movement of GEM objects between LRUs. All - * LRUs that the object can move between should be protected - * by the same lock. - */ - struct mutex *lock; - /** * @count: * @@ -453,6 +447,9 @@ struct drm_gem_object { * @lru: * * The current LRU list that the GEM object is on. + * + * Access to this field must be done with drm_device::gem_lru_mutex + * held. */ struct drm_gem_lru *lru; }; @@ -610,12 +607,13 @@ void drm_gem_unlock_reservations(struct drm_gem_object **objs, int count, int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev, u32 handle, u64 *offset); -void drm_gem_lru_init(struct drm_gem_lru *lru, struct mutex *lock); +void drm_gem_lru_init(struct drm_gem_lru *lru); void drm_gem_lru_remove(struct drm_gem_object *obj); void drm_gem_lru_move_tail_locked(struct drm_gem_lru *lru, struct drm_gem_object *obj); void drm_gem_lru_move_tail(struct drm_gem_lru *lru, struct drm_gem_object *obj); unsigned long -drm_gem_lru_scan(struct drm_gem_lru *lru, +drm_gem_lru_scan(struct drm_device *dev, + struct drm_gem_lru *lru, unsigned int nr_to_scan, unsigned long *remaining, bool (*shrink)(struct drm_gem_object *obj, struct ww_acquire_ctx *ticket), --- base-commit: b2ed01e7ad3de80333e9b962a44024b094bc0b2b change-id: 20260506-panthor-shrinker-fixes-58c1f45cfc41 Best regards, -- Boris Brezillon