From d5971c5c34303a00bf841a902ca00a703602c500 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Christian=20K=C3=B6nig?= Date: Mon, 20 Apr 2026 20:18:43 +0200 Subject: [PATCH 1/7] drm/amdgpu: remove deadlocks from amdgpu_userq_pre_reset MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The purpose of a GPU reset is to make sure that fence can be signaled again and the signal and resume workers can make progress again. So waiting for the resume worker or any fence in the GPU reset path is just utterly nonsense. Signed-off-by: Christian König Reviewed-by: Prike Liang Signed-off-by: Alex Deucher (cherry picked from commit fcd5f065eab46993af43442fd77ee8d9eb9c5bdf) --- drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c | 26 +++++++++++------------ 1 file changed, 12 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c index de140a8ed135..692f7e3513df 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c @@ -1504,23 +1504,21 @@ void amdgpu_userq_pre_reset(struct amdgpu_device *adev) { const struct amdgpu_userq_funcs *userq_funcs; struct amdgpu_usermode_queue *queue; - struct amdgpu_userq_mgr *uqm; unsigned long queue_id; + /* TODO: We probably need a new lock for the queue state */ xa_for_each(&adev->userq_doorbell_xa, queue_id, queue) { - uqm = queue->userq_mgr; - cancel_delayed_work_sync(&uqm->resume_work); - if (queue->state == AMDGPU_USERQ_STATE_MAPPED) { - amdgpu_userq_wait_for_last_fence(queue); - userq_funcs = adev->userq_funcs[queue->queue_type]; - userq_funcs->unmap(queue); - /* just mark all queues as hung at this point. - * if unmap succeeds, we could map again - * in amdgpu_userq_post_reset() if vram is not lost - */ - queue->state = AMDGPU_USERQ_STATE_HUNG; - amdgpu_userq_fence_driver_force_completion(queue); - } + if (queue->state != AMDGPU_USERQ_STATE_MAPPED) + continue; + + userq_funcs = adev->userq_funcs[queue->queue_type]; + userq_funcs->unmap(queue); + /* just mark all queues as hung at this point. + * if unmap succeeds, we could map again + * in amdgpu_userq_post_reset() if vram is not lost + */ + queue->state = AMDGPU_USERQ_STATE_HUNG; + amdgpu_userq_fence_driver_force_completion(queue); } } From 44e5bc73bdcbec115cfe1c4b4394d25eb3deaff2 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Christian=20K=C3=B6nig?= Date: Thu, 16 Apr 2026 15:32:11 +0200 Subject: [PATCH 2/7] drm/amdgpu: rework amdgpu_userq_signal_ioctl v3 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This one was fortunately not looking so bad as the wait ioctl path, but there were still a few things which could be fixed/improved: 1. Allocating with GFP_ATOMIC was quite unnecessary, we can do that before taking the userq_lock. 2. Use a new mutex as protection for the fence_drv_xa so that we can do memory allocations while holding it. 3. Starting the reset timer is unnecessary when the fence is already signaled when we create it. 4. Cleanup error handling, avoid trying to free the queue when we don't even got one. v2: fix incorrect usage of xa_find, destroy the new mutex on error v3: cleanup ref ordering Signed-off-by: Christian König Reviewed-by: Sunil Khatri Signed-off-by: Alex Deucher (cherry picked from commit 1609eb0f81a609d350169839128cecf298c84e7a) --- drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c | 2 + drivers/gpu/drm/amd/amdgpu/amdgpu_userq.h | 12 + .../gpu/drm/amd/amdgpu/amdgpu_userq_fence.c | 228 ++++++++---------- 3 files changed, 120 insertions(+), 122 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c index 692f7e3513df..2d4f159f3362 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c @@ -800,6 +800,7 @@ amdgpu_userq_create(struct drm_file *filp, union drm_amdgpu_userq *args) } queue->doorbell_index = index; + mutex_init(&queue->fence_drv_lock); xa_init_flags(&queue->fence_drv_xa, XA_FLAGS_ALLOC); r = amdgpu_userq_fence_driver_alloc(adev, &queue->fence_drv); if (r) { @@ -873,6 +874,7 @@ amdgpu_userq_create(struct drm_file *filp, union drm_amdgpu_userq *args) amdgpu_bo_reserve(fpriv->vm.root.bo, true); amdgpu_userq_buffer_vas_list_cleanup(adev, queue); amdgpu_bo_unreserve(fpriv->vm.root.bo); + mutex_destroy(&queue->fence_drv_lock); free_queue: kfree(queue); err_pm_runtime: diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.h index 8b8f345b60b6..843ea8ecc5d7 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.h @@ -66,6 +66,18 @@ struct amdgpu_usermode_queue { struct amdgpu_userq_obj db_obj; struct amdgpu_userq_obj fw_obj; struct amdgpu_userq_obj wptr_obj; + + /** + * @fence_drv_lock: Protecting @fence_drv_xa. + */ + struct mutex fence_drv_lock; + + /** + * @fence_drv_xa: + * + * References to the external fence drivers returned by wait_ioctl. + * Dropped on the next signaled dma_fence or queue destruction. + */ struct xarray fence_drv_xa; struct amdgpu_userq_fence_driver *fence_drv; struct dma_fence *last_fence; diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c index e2d5f04296e1..c9dbf03c4eea 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c @@ -121,6 +121,7 @@ amdgpu_userq_fence_driver_free(struct amdgpu_usermode_queue *userq) userq->last_fence = NULL; amdgpu_userq_walk_and_drop_fence_drv(&userq->fence_drv_xa); xa_destroy(&userq->fence_drv_xa); + mutex_destroy(&userq->fence_drv_lock); /* Drop the queue's ownership reference to fence_drv explicitly */ amdgpu_userq_fence_driver_put(userq->fence_drv); } @@ -209,80 +210,84 @@ void amdgpu_userq_fence_driver_put(struct amdgpu_userq_fence_driver *fence_drv) kref_put(&fence_drv->refcount, amdgpu_userq_fence_driver_destroy); } -static int amdgpu_userq_fence_alloc(struct amdgpu_userq_fence **userq_fence) +static int amdgpu_userq_fence_alloc(struct amdgpu_usermode_queue *userq, + struct amdgpu_userq_fence **pfence) { - *userq_fence = kmalloc(sizeof(**userq_fence), GFP_KERNEL); - return *userq_fence ? 0 : -ENOMEM; + struct amdgpu_userq_fence_driver *fence_drv = userq->fence_drv; + struct amdgpu_userq_fence *userq_fence; + void *entry; + + userq_fence = kmalloc(sizeof(*userq_fence), GFP_KERNEL); + if (!userq_fence) + return -ENOMEM; + + /* + * Get the next unused entry, since we fill from the start this can be + * used as size to allocate the array. + */ + mutex_lock(&userq->fence_drv_lock); + XA_STATE(xas, &userq->fence_drv_xa, 0); + + rcu_read_lock(); + do { + entry = xas_find_marked(&xas, ULONG_MAX, XA_FREE_MARK); + } while (xas_retry(&xas, entry)); + rcu_read_unlock(); + + userq_fence->fence_drv_array = kvmalloc_array(xas.xa_index, + sizeof(fence_drv), + GFP_KERNEL); + if (!userq_fence->fence_drv_array) { + mutex_unlock(&userq->fence_drv_lock); + kfree(userq_fence); + return -ENOMEM; + } + + userq_fence->fence_drv_array_count = xas.xa_index; + xa_extract(&userq->fence_drv_xa, (void **)userq_fence->fence_drv_array, + 0, ULONG_MAX, xas.xa_index, XA_PRESENT); + xa_destroy(&userq->fence_drv_xa); + + mutex_unlock(&userq->fence_drv_lock); + + amdgpu_userq_fence_driver_get(fence_drv); + userq_fence->fence_drv = fence_drv; + + *pfence = userq_fence; + return 0; } -static int amdgpu_userq_fence_create(struct amdgpu_usermode_queue *userq, - struct amdgpu_userq_fence *userq_fence, - u64 seq, struct dma_fence **f) +static void amdgpu_userq_fence_init(struct amdgpu_usermode_queue *userq, + struct amdgpu_userq_fence *fence, + u64 seq) { - struct amdgpu_userq_fence_driver *fence_drv; - struct dma_fence *fence; + struct amdgpu_userq_fence_driver *fence_drv = userq->fence_drv; unsigned long flags; bool signaled = false; - fence_drv = userq->fence_drv; - if (!fence_drv) - return -EINVAL; - - spin_lock_init(&userq_fence->lock); - INIT_LIST_HEAD(&userq_fence->link); - fence = &userq_fence->base; - userq_fence->fence_drv = fence_drv; - - dma_fence_init64(fence, &amdgpu_userq_fence_ops, &userq_fence->lock, + spin_lock_init(&fence->lock); + dma_fence_init64(&fence->base, &amdgpu_userq_fence_ops, &fence->lock, fence_drv->context, seq); - amdgpu_userq_fence_driver_get(fence_drv); - dma_fence_get(fence); + /* Make sure the fence is visible to the hang detect worker */ + dma_fence_put(userq->last_fence); + userq->last_fence = dma_fence_get(&fence->base); - if (!xa_empty(&userq->fence_drv_xa)) { - struct amdgpu_userq_fence_driver *stored_fence_drv; - unsigned long index, count = 0; - int i = 0; - - xa_lock(&userq->fence_drv_xa); - xa_for_each(&userq->fence_drv_xa, index, stored_fence_drv) - count++; - - userq_fence->fence_drv_array = - kvmalloc_objs(struct amdgpu_userq_fence_driver *, count, - GFP_ATOMIC); - - if (userq_fence->fence_drv_array) { - xa_for_each(&userq->fence_drv_xa, index, stored_fence_drv) { - userq_fence->fence_drv_array[i] = stored_fence_drv; - __xa_erase(&userq->fence_drv_xa, index); - i++; - } - } - - userq_fence->fence_drv_array_count = i; - xa_unlock(&userq->fence_drv_xa); - } else { - userq_fence->fence_drv_array = NULL; - userq_fence->fence_drv_array_count = 0; - } - - /* Check if hardware has already processed the job */ + /* Check if hardware has already processed the fence */ spin_lock_irqsave(&fence_drv->fence_list_lock, flags); - if (!dma_fence_is_signaled(fence)) { - list_add_tail(&userq_fence->link, &fence_drv->fences); + if (!dma_fence_is_signaled(&fence->base)) { + dma_fence_get(&fence->base); + list_add_tail(&fence->link, &fence_drv->fences); } else { + INIT_LIST_HEAD(&fence->link); signaled = true; - dma_fence_put(fence); } spin_unlock_irqrestore(&fence_drv->fence_list_lock, flags); if (signaled) - amdgpu_userq_fence_put_fence_drv_array(userq_fence); - - *f = fence; - - return 0; + amdgpu_userq_fence_put_fence_drv_array(fence); + else + amdgpu_userq_start_hang_detect_work(userq); } static const char *amdgpu_userq_fence_get_driver_name(struct dma_fence *f) @@ -403,11 +408,6 @@ static int amdgpu_userq_fence_read_wptr(struct amdgpu_device *adev, return r; } -static void amdgpu_userq_fence_cleanup(struct dma_fence *fence) -{ - dma_fence_put(fence); -} - static void amdgpu_userq_fence_driver_set_error(struct amdgpu_userq_fence *fence, int error) @@ -451,13 +451,14 @@ int amdgpu_userq_signal_ioctl(struct drm_device *dev, void *data, const unsigned int num_read_bo_handles = args->num_bo_read_handles; struct amdgpu_fpriv *fpriv = filp->driver_priv; struct amdgpu_userq_mgr *userq_mgr = &fpriv->userq_mgr; + struct drm_gem_object **gobj_write, **gobj_read; u32 *syncobj_handles, num_syncobj_handles; - struct amdgpu_userq_fence *userq_fence; - struct amdgpu_usermode_queue *queue = NULL; - struct drm_syncobj **syncobj = NULL; - struct dma_fence *fence; + struct amdgpu_usermode_queue *queue; + struct amdgpu_userq_fence *fence; + struct drm_syncobj **syncobj; struct drm_exec exec; + void __user *ptr; int r, i, entry; u64 wptr; @@ -469,13 +470,14 @@ int amdgpu_userq_signal_ioctl(struct drm_device *dev, void *data, return -EINVAL; num_syncobj_handles = args->num_syncobj_handles; - syncobj_handles = memdup_array_user(u64_to_user_ptr(args->syncobj_handles), - num_syncobj_handles, sizeof(u32)); + ptr = u64_to_user_ptr(args->syncobj_handles); + syncobj_handles = memdup_array_user(ptr, num_syncobj_handles, + sizeof(u32)); if (IS_ERR(syncobj_handles)) return PTR_ERR(syncobj_handles); - /* Array of pointers to the looked up syncobjs */ - syncobj = kmalloc_array(num_syncobj_handles, sizeof(*syncobj), GFP_KERNEL); + syncobj = kmalloc_array(num_syncobj_handles, sizeof(*syncobj), + GFP_KERNEL); if (!syncobj) { r = -ENOMEM; goto free_syncobj_handles; @@ -489,21 +491,17 @@ int amdgpu_userq_signal_ioctl(struct drm_device *dev, void *data, } } - r = drm_gem_objects_lookup(filp, - u64_to_user_ptr(args->bo_read_handles), - num_read_bo_handles, - &gobj_read); + ptr = u64_to_user_ptr(args->bo_read_handles); + r = drm_gem_objects_lookup(filp, ptr, num_read_bo_handles, &gobj_read); if (r) goto free_syncobj; - r = drm_gem_objects_lookup(filp, - u64_to_user_ptr(args->bo_write_handles), - num_write_bo_handles, + ptr = u64_to_user_ptr(args->bo_write_handles); + r = drm_gem_objects_lookup(filp, ptr, num_write_bo_handles, &gobj_write); if (r) goto put_gobj_read; - /* Retrieve the user queue */ queue = amdgpu_userq_get(userq_mgr, args->queue_id); if (!queue) { r = -ENOENT; @@ -512,73 +510,61 @@ int amdgpu_userq_signal_ioctl(struct drm_device *dev, void *data, r = amdgpu_userq_fence_read_wptr(adev, queue, &wptr); if (r) - goto put_gobj_write; + goto put_queue; - r = amdgpu_userq_fence_alloc(&userq_fence); + r = amdgpu_userq_fence_alloc(queue, &fence); if (r) - goto put_gobj_write; + goto put_queue; /* We are here means UQ is active, make sure the eviction fence is valid */ amdgpu_userq_ensure_ev_fence(&fpriv->userq_mgr, &fpriv->evf_mgr); - /* Create a new fence */ - r = amdgpu_userq_fence_create(queue, userq_fence, wptr, &fence); - if (r) { - mutex_unlock(&userq_mgr->userq_mutex); - kfree(userq_fence); - goto put_gobj_write; - } + /* Create the new fence */ + amdgpu_userq_fence_init(queue, fence, wptr); - dma_fence_put(queue->last_fence); - queue->last_fence = dma_fence_get(fence); - amdgpu_userq_start_hang_detect_work(queue); mutex_unlock(&userq_mgr->userq_mutex); + /* + * This needs to come after the fence is created since + * amdgpu_userq_ensure_ev_fence() can't be called while holding the resv + * locks. + */ drm_exec_init(&exec, DRM_EXEC_INTERRUPTIBLE_WAIT, (num_read_bo_handles + num_write_bo_handles)); - /* Lock all BOs with retry handling */ drm_exec_until_all_locked(&exec) { - r = drm_exec_prepare_array(&exec, gobj_read, num_read_bo_handles, 1); + r = drm_exec_prepare_array(&exec, gobj_read, + num_read_bo_handles, 1); drm_exec_retry_on_contention(&exec); - if (r) { - amdgpu_userq_fence_cleanup(fence); + if (r) goto exec_fini; - } - r = drm_exec_prepare_array(&exec, gobj_write, num_write_bo_handles, 1); + r = drm_exec_prepare_array(&exec, gobj_write, + num_write_bo_handles, 1); drm_exec_retry_on_contention(&exec); - if (r) { - amdgpu_userq_fence_cleanup(fence); + if (r) goto exec_fini; - } } - for (i = 0; i < num_read_bo_handles; i++) { - if (!gobj_read || !gobj_read[i]->resv) - continue; - - dma_resv_add_fence(gobj_read[i]->resv, fence, + /* And publish the new fence in the BOs and syncobj */ + for (i = 0; i < num_read_bo_handles; i++) + dma_resv_add_fence(gobj_read[i]->resv, &fence->base, DMA_RESV_USAGE_READ); - } - for (i = 0; i < num_write_bo_handles; i++) { - if (!gobj_write || !gobj_write[i]->resv) - continue; - - dma_resv_add_fence(gobj_write[i]->resv, fence, + for (i = 0; i < num_write_bo_handles; i++) + dma_resv_add_fence(gobj_write[i]->resv, &fence->base, DMA_RESV_USAGE_WRITE); - } - /* Add the created fence to syncobj/BO's */ for (i = 0; i < num_syncobj_handles; i++) - drm_syncobj_replace_fence(syncobj[i], fence); - - /* drop the reference acquired in fence creation function */ - dma_fence_put(fence); + drm_syncobj_replace_fence(syncobj[i], &fence->base); exec_fini: + /* drop the reference acquired in fence creation function */ + dma_fence_put(&fence->base); + drm_exec_fini(&exec); +put_queue: + amdgpu_userq_put(queue); put_gobj_write: for (i = 0; i < num_write_bo_handles; i++) drm_gem_object_put(gobj_write[i]); @@ -589,15 +575,11 @@ int amdgpu_userq_signal_ioctl(struct drm_device *dev, void *data, kvfree(gobj_read); free_syncobj: while (entry-- > 0) - if (syncobj[entry]) - drm_syncobj_put(syncobj[entry]); + drm_syncobj_put(syncobj[entry]); kfree(syncobj); free_syncobj_handles: kfree(syncobj_handles); - if (queue) - amdgpu_userq_put(queue); - return r; } @@ -872,8 +854,10 @@ amdgpu_userq_wait_return_fence_info(struct drm_file *filp, * Otherwise, we would gather those references until we don't * have any more space left and crash. */ + mutex_lock(&waitq->fence_drv_lock); r = xa_alloc(&waitq->fence_drv_xa, &index, fence_drv, xa_limit_32b, GFP_KERNEL); + mutex_unlock(&waitq->fence_drv_lock); if (r) goto put_waitq; From d0053441ad7eaf7920b71e2263097ece53c5af34 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Christian=20K=C3=B6nig?= Date: Mon, 20 Apr 2026 15:13:57 +0200 Subject: [PATCH 3/7] drm/amdgpu: remove almost all calls to amdgpu_userq_detect_and_reset_queues MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Well the reset handling seems broken on multiple levels. As first step of fixing this remove most calls to the hang detection. That function should only be called after we run into a timeout! And *NOT* as random check spread over the code in multiple places. Signed-off-by: Christian König Reviewed-by: Sunil Khatri Signed-off-by: Alex Deucher (cherry picked from commit 71bea36b54ccfb14cbc90f94267af6369af4e702) --- drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c | 38 +++++++++-------------- 1 file changed, 14 insertions(+), 24 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c index 2d4f159f3362..ba03d2a42e1e 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c @@ -345,23 +345,18 @@ static int amdgpu_userq_preempt_helper(struct amdgpu_usermode_queue *queue) struct amdgpu_device *adev = uq_mgr->adev; const struct amdgpu_userq_funcs *userq_funcs = adev->userq_funcs[queue->queue_type]; - bool found_hung_queue = false; - int r = 0; + int r; if (queue->state == AMDGPU_USERQ_STATE_MAPPED) { r = userq_funcs->preempt(queue); if (r) { queue->state = AMDGPU_USERQ_STATE_HUNG; - found_hung_queue = true; + return r; } else { queue->state = AMDGPU_USERQ_STATE_PREEMPTED; } } - - if (found_hung_queue) - amdgpu_userq_detect_and_reset_queues(uq_mgr); - - return r; + return 0; } static int amdgpu_userq_restore_helper(struct amdgpu_usermode_queue *queue) @@ -390,24 +385,21 @@ static int amdgpu_userq_unmap_helper(struct amdgpu_usermode_queue *queue) struct amdgpu_device *adev = uq_mgr->adev; const struct amdgpu_userq_funcs *userq_funcs = adev->userq_funcs[queue->queue_type]; - bool found_hung_queue = false; - int r = 0; + int r; if ((queue->state == AMDGPU_USERQ_STATE_MAPPED) || - (queue->state == AMDGPU_USERQ_STATE_PREEMPTED)) { + (queue->state == AMDGPU_USERQ_STATE_PREEMPTED)) { + r = userq_funcs->unmap(queue); if (r) { queue->state = AMDGPU_USERQ_STATE_HUNG; - found_hung_queue = true; + return r; } else { queue->state = AMDGPU_USERQ_STATE_UNMAPPED; } } - if (found_hung_queue) - amdgpu_userq_detect_and_reset_queues(uq_mgr); - - return r; + return 0; } static int amdgpu_userq_map_helper(struct amdgpu_usermode_queue *queue) @@ -416,19 +408,19 @@ static int amdgpu_userq_map_helper(struct amdgpu_usermode_queue *queue) struct amdgpu_device *adev = uq_mgr->adev; const struct amdgpu_userq_funcs *userq_funcs = adev->userq_funcs[queue->queue_type]; - int r = 0; + int r; if (queue->state == AMDGPU_USERQ_STATE_UNMAPPED) { r = userq_funcs->map(queue); if (r) { queue->state = AMDGPU_USERQ_STATE_HUNG; - amdgpu_userq_detect_and_reset_queues(uq_mgr); + return r; } else { queue->state = AMDGPU_USERQ_STATE_MAPPED; } } - return r; + return 0; } static void amdgpu_userq_wait_for_last_fence(struct amdgpu_usermode_queue *queue) @@ -654,7 +646,6 @@ amdgpu_userq_destroy(struct amdgpu_userq_mgr *uq_mgr, struct amdgpu_usermode_que #if defined(CONFIG_DEBUG_FS) debugfs_remove_recursive(queue->debugfs_queue); #endif - amdgpu_userq_detect_and_reset_queues(uq_mgr); r = amdgpu_userq_unmap_helper(queue); atomic_dec(&uq_mgr->userq_count[queue->queue_type]); amdgpu_userq_cleanup(queue); @@ -1264,7 +1255,6 @@ amdgpu_userq_evict_all(struct amdgpu_userq_mgr *uq_mgr) unsigned long queue_id; int ret = 0, r; - amdgpu_userq_detect_and_reset_queues(uq_mgr); /* Try to unmap all the queues in this process ctx */ xa_for_each(&uq_mgr->userq_xa, queue_id, queue) { r = amdgpu_userq_preempt_helper(queue); @@ -1272,9 +1262,11 @@ amdgpu_userq_evict_all(struct amdgpu_userq_mgr *uq_mgr) ret = r; } - if (ret) + if (ret) { drm_file_err(uq_mgr->file, "Couldn't unmap all the queues, eviction failed ret=%d\n", ret); + amdgpu_userq_detect_and_reset_queues(uq_mgr); + } return ret; } @@ -1374,7 +1366,6 @@ int amdgpu_userq_suspend(struct amdgpu_device *adev) uqm = queue->userq_mgr; cancel_delayed_work_sync(&uqm->resume_work); guard(mutex)(&uqm->userq_mutex); - amdgpu_userq_detect_and_reset_queues(uqm); if (adev->in_s0ix) r = amdgpu_userq_preempt_helper(queue); else @@ -1433,7 +1424,6 @@ int amdgpu_userq_stop_sched_for_enforce_isolation(struct amdgpu_device *adev, if (((queue->queue_type == AMDGPU_HW_IP_GFX) || (queue->queue_type == AMDGPU_HW_IP_COMPUTE)) && (queue->xcp_id == idx)) { - amdgpu_userq_detect_and_reset_queues(uqm); r = amdgpu_userq_preempt_helper(queue); if (r) ret = r; From 0071e01c61aa73f22edd5252f0a3e2c2eff744d6 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Christian=20K=C3=B6nig?= Date: Mon, 20 Apr 2026 16:08:35 +0200 Subject: [PATCH 4/7] drm/amdgpu: fix userq hang detection and reset MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Fix lock inversions pointed out by Prike and Sunil. The hang detection timeout *CAN'T* grab locks under which we wait for fences, especially not the userq_mutex lock. Then instead of this completely broken handling with the hang_detect_fence just cancel the work when fences are processed and re-start if necessary. Signed-off-by: Christian König Reviewed-by: Sunil Khatri Signed-off-by: Alex Deucher (cherry picked from commit 1b62077f045ac6ffde7c97005c6659569ac5c1ec) --- drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c | 65 ++++++++----------- drivers/gpu/drm/amd/amdgpu/amdgpu_userq.h | 1 - .../gpu/drm/amd/amdgpu/amdgpu_userq_fence.c | 17 +++-- .../gpu/drm/amd/amdgpu/amdgpu_userq_fence.h | 2 +- 4 files changed, 40 insertions(+), 45 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c index ba03d2a42e1e..70d74f04d2dd 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.c @@ -106,9 +106,6 @@ amdgpu_userq_detect_and_reset_queues(struct amdgpu_userq_mgr *uq_mgr) int r = 0; int i; - /* Warning if current process mutex is not held */ - WARN_ON(!mutex_is_locked(&uq_mgr->userq_mutex)); - if (unlikely(adev->debug_disable_gpu_ring_reset)) { dev_err(adev->dev, "userq reset disabled by debug mask\n"); return 0; @@ -127,9 +124,11 @@ amdgpu_userq_detect_and_reset_queues(struct amdgpu_userq_mgr *uq_mgr) */ for (i = 0; i < num_queue_types; i++) { int ring_type = queue_types[i]; - const struct amdgpu_userq_funcs *funcs = adev->userq_funcs[ring_type]; + const struct amdgpu_userq_funcs *funcs = + adev->userq_funcs[ring_type]; - if (!amdgpu_userq_is_reset_type_supported(adev, ring_type, AMDGPU_RESET_TYPE_PER_QUEUE)) + if (!amdgpu_userq_is_reset_type_supported(adev, ring_type, + AMDGPU_RESET_TYPE_PER_QUEUE)) continue; if (atomic_read(&uq_mgr->userq_count[ring_type]) > 0 && @@ -150,38 +149,22 @@ amdgpu_userq_detect_and_reset_queues(struct amdgpu_userq_mgr *uq_mgr) static void amdgpu_userq_hang_detect_work(struct work_struct *work) { - struct amdgpu_usermode_queue *queue = container_of(work, - struct amdgpu_usermode_queue, - hang_detect_work.work); - struct dma_fence *fence; - struct amdgpu_userq_mgr *uq_mgr; + struct amdgpu_usermode_queue *queue = + container_of(work, struct amdgpu_usermode_queue, + hang_detect_work.work); - if (!queue->userq_mgr) - return; - - uq_mgr = queue->userq_mgr; - fence = READ_ONCE(queue->hang_detect_fence); - /* Fence already signaled – no action needed */ - if (!fence || dma_fence_is_signaled(fence)) - return; - - mutex_lock(&uq_mgr->userq_mutex); - amdgpu_userq_detect_and_reset_queues(uq_mgr); - mutex_unlock(&uq_mgr->userq_mutex); + amdgpu_userq_detect_and_reset_queues(queue->userq_mgr); } /* * Start hang detection for a user queue fence. A delayed work will be scheduled - * to check if the fence is still pending after the timeout period. -*/ + * to reset the queues when the fence doesn't signal in time. + */ void amdgpu_userq_start_hang_detect_work(struct amdgpu_usermode_queue *queue) { struct amdgpu_device *adev; unsigned long timeout_ms; - if (!queue || !queue->userq_mgr || !queue->userq_mgr->adev) - return; - adev = queue->userq_mgr->adev; /* Determine timeout based on queue type */ switch (queue->queue_type) { @@ -199,8 +182,6 @@ void amdgpu_userq_start_hang_detect_work(struct amdgpu_usermode_queue *queue) break; } - /* Store the fence to monitor and schedule hang detection */ - WRITE_ONCE(queue->hang_detect_fence, queue->last_fence); schedule_delayed_work(&queue->hang_detect_work, msecs_to_jiffies(timeout_ms)); } @@ -210,18 +191,24 @@ void amdgpu_userq_process_fence_irq(struct amdgpu_device *adev, u32 doorbell) struct xarray *xa = &adev->userq_doorbell_xa; struct amdgpu_usermode_queue *queue; unsigned long flags; + int r; xa_lock_irqsave(xa, flags); queue = xa_load(xa, doorbell); - if (queue) - amdgpu_userq_fence_driver_process(queue->fence_drv); - xa_unlock_irqrestore(xa, flags); -} + if (queue) { + r = amdgpu_userq_fence_driver_process(queue->fence_drv); + /* + * We are in interrupt context here, this *can't* wait for + * reset work to finish. + */ + if (r >= 0) + cancel_delayed_work(&queue->hang_detect_work); -static void amdgpu_userq_init_hang_detect_work(struct amdgpu_usermode_queue *queue) -{ - INIT_DELAYED_WORK(&queue->hang_detect_work, amdgpu_userq_hang_detect_work); - queue->hang_detect_fence = NULL; + /* Restart the timer when there are still fences pending */ + if (r == 1) + amdgpu_userq_start_hang_detect_work(queue); + } + xa_unlock_irqrestore(xa, flags); } static int amdgpu_userq_buffer_va_list_add(struct amdgpu_usermode_queue *queue, @@ -640,7 +627,6 @@ amdgpu_userq_destroy(struct amdgpu_userq_mgr *uq_mgr, struct amdgpu_usermode_que amdgpu_bo_unreserve(vm->root.bo); mutex_lock(&uq_mgr->userq_mutex); - queue->hang_detect_fence = NULL; amdgpu_userq_wait_for_last_fence(queue); #if defined(CONFIG_DEBUG_FS) @@ -847,7 +833,8 @@ amdgpu_userq_create(struct drm_file *filp, union drm_amdgpu_userq *args) up_read(&adev->reset_domain->sem); amdgpu_debugfs_userq_init(filp, queue, qid); - amdgpu_userq_init_hang_detect_work(queue); + INIT_DELAYED_WORK(&queue->hang_detect_work, + amdgpu_userq_hang_detect_work); args->out.queue_id = qid; atomic_inc(&uq_mgr->userq_count[queue->queue_type]); diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.h index 843ea8ecc5d7..85f460e7c31b 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq.h @@ -85,7 +85,6 @@ struct amdgpu_usermode_queue { int priority; struct dentry *debugfs_queue; struct delayed_work hang_detect_work; - struct dma_fence *hang_detect_fence; struct kref refcount; struct list_head userq_va_list; diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c index c9dbf03c4eea..53a8944bab05 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c @@ -135,7 +135,14 @@ amdgpu_userq_fence_put_fence_drv_array(struct amdgpu_userq_fence *userq_fence) userq_fence->fence_drv_array_count = 0; } -void amdgpu_userq_fence_driver_process(struct amdgpu_userq_fence_driver *fence_drv) +/* + * Returns: + * -ENOENT when no fences were processes + * 1 when more fences are pending + * 0 when no fences are pending any more + */ +int +amdgpu_userq_fence_driver_process(struct amdgpu_userq_fence_driver *fence_drv) { struct amdgpu_userq_fence *userq_fence, *tmp; LIST_HEAD(to_be_signaled); @@ -143,9 +150,6 @@ void amdgpu_userq_fence_driver_process(struct amdgpu_userq_fence_driver *fence_d unsigned long flags; u64 rptr; - if (!fence_drv) - return; - spin_lock_irqsave(&fence_drv->fence_list_lock, flags); rptr = amdgpu_userq_fence_read(fence_drv); @@ -158,6 +162,9 @@ void amdgpu_userq_fence_driver_process(struct amdgpu_userq_fence_driver *fence_d &userq_fence->link); spin_unlock_irqrestore(&fence_drv->fence_list_lock, flags); + if (list_empty(&to_be_signaled)) + return -ENOENT; + list_for_each_entry_safe(userq_fence, tmp, &to_be_signaled, link) { fence = &userq_fence->base; list_del_init(&userq_fence->link); @@ -169,6 +176,8 @@ void amdgpu_userq_fence_driver_process(struct amdgpu_userq_fence_driver *fence_d dma_fence_put(fence); } + /* That doesn't need to be accurate so no locking */ + return list_empty(&fence_drv->fences) ? 0 : 1; } void amdgpu_userq_fence_driver_destroy(struct kref *ref) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.h index d355a0eecc07..0bd51616cef1 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.h @@ -63,7 +63,7 @@ void amdgpu_userq_fence_driver_put(struct amdgpu_userq_fence_driver *fence_drv); int amdgpu_userq_fence_driver_alloc(struct amdgpu_device *adev, struct amdgpu_userq_fence_driver **fence_drv_req); void amdgpu_userq_fence_driver_free(struct amdgpu_usermode_queue *userq); -void amdgpu_userq_fence_driver_process(struct amdgpu_userq_fence_driver *fence_drv); +int amdgpu_userq_fence_driver_process(struct amdgpu_userq_fence_driver *fence_drv); void amdgpu_userq_fence_driver_force_completion(struct amdgpu_usermode_queue *userq); void amdgpu_userq_fence_driver_destroy(struct kref *ref); int amdgpu_userq_signal_ioctl(struct drm_device *dev, void *data, From 183182235f6d53bac62c6c39014738a54a68dfa6 Mon Sep 17 00:00:00 2001 From: Mikhail Gavrilov Date: Tue, 5 May 2026 09:05:37 +0800 Subject: [PATCH 5/7] drm/amd/display: Wrap DCN32 phantom-plane allocation in DC_RUN_WITH_PREEMPTION_ENABLED [Why] dcn32_validate_bandwidth() wraps dcn32_internal_validate_bw() with DC_FP_START()/DC_FP_END(). In x86 non-RT, DC_FP_START takes fpregs_lock(), which disables local softirqs. The DML1 path through dcn32_enable_phantom_plane() calls kvzalloc() to allocate ~335 KiB for dc_plane_state. This triggers the vmalloc path, which calls BUG_ON(in_interrupt()) because it's invoked within the FPU-enabled (softirq disabled) region, leading to a kernel crash. [How] Wrap the dc_state_create_phantom_plane() call with the DC_RUN_WITH_PREEMPTION_ENABLED() macro to allow preemption during this memory allocation. Fixes: 235c67634230 ("drm/amd/display: add DCN32/321 specific files for Display Core") Closes: https://gitlab.freedesktop.org/drm/amd/-/work_items/4470 Reviewed-by: Aurabindo Pillai Signed-off-by: Mikhail Gavrilov Signed-off-by: James Lin Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 885ccbef7b94a8b38f69c4211c679021aa27ad11) Cc: stable@vger.kernel.org --- .../drm/amd/display/dc/resource/dcn32/dcn32_resource.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c index 82f81b586986..3751f7a94a05 100644 --- a/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c +++ b/drivers/gpu/drm/amd/display/dc/resource/dcn32/dcn32_resource.c @@ -92,9 +92,14 @@ #include "dml/dcn32/dcn32_fpu.h" #include "dc_state_priv.h" +#include "dc_fpu.h" #include "dml2_0/dml2_wrapper.h" +#if !defined(DC_RUN_WITH_PREEMPTION_ENABLED) +#define DC_RUN_WITH_PREEMPTION_ENABLED(code) code +#endif + #define DC_LOGGER_INIT(logger) enum dcn32_clk_src_array_id { @@ -1684,7 +1689,8 @@ static void dcn32_enable_phantom_plane(struct dc *dc, if (curr_pipe->top_pipe && curr_pipe->top_pipe->plane_state == curr_pipe->plane_state) phantom_plane = prev_phantom_plane; else - phantom_plane = dc_state_create_phantom_plane(dc, context, curr_pipe->plane_state); + DC_RUN_WITH_PREEMPTION_ENABLED(phantom_plane = + dc_state_create_phantom_plane(dc, context, curr_pipe->plane_state)); if (!phantom_plane) continue; From 6bbede02dc62a1021aeeae87ab243bd7a93c61d2 Mon Sep 17 00:00:00 2001 From: Xiang Liu Date: Thu, 7 May 2026 20:56:15 +0800 Subject: [PATCH 6/7] drm/amd/ras: Fix CPER ring debugfs read overflow The legacy CPER debugfs reader can reach the payload path without a valid pointer snapshot. The remaining user byte count is also treated as the ring occupancy in dwords, so reads past the header can copy more than requested. Take the CPER lock before sampling pointers. Resample rptr/wptr for payload reads, bound the payload copy by available dwords and the remaining user size, and advance the file position for each dword copied. Signed-off-by: Xiang Liu Reviewed-by: Tao Zhou Signed-off-by: Alex Deucher (cherry picked from commit 1e40ef87ffdc291e05ccdade8b9170cc9c1c4249) --- drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c | 29 +++++++++++++++++------- 1 file changed, 21 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c index 66e8a2f7afcf..d6bee5c30073 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c @@ -552,8 +552,9 @@ static ssize_t amdgpu_debugfs_ring_read(struct file *f, char __user *buf, size_t size, loff_t *pos) { struct amdgpu_ring *ring = file_inode(f)->i_private; - uint32_t value, result, early[3]; + u32 value, result, early[3] = { 0 }; uint64_t p; + u32 avail_dw, start_dw, read_dw; loff_t i; int r; @@ -565,10 +566,10 @@ static ssize_t amdgpu_debugfs_ring_read(struct file *f, char __user *buf, result = 0; - if (*pos < 12) { - if (ring->funcs->type == AMDGPU_RING_TYPE_CPER) - mutex_lock(&ring->adev->cper.ring_lock); + if (ring->funcs->type == AMDGPU_RING_TYPE_CPER) + mutex_lock(&ring->adev->cper.ring_lock); + if (*pos < 12) { early[0] = amdgpu_ring_get_rptr(ring) & ring->buf_mask; early[1] = amdgpu_ring_get_wptr(ring) & ring->buf_mask; early[2] = ring->wptr & ring->buf_mask; @@ -600,13 +601,24 @@ static ssize_t amdgpu_debugfs_ring_read(struct file *f, char __user *buf, *pos += 4; } } else { + early[0] = amdgpu_ring_get_rptr(ring) & ring->buf_mask; + early[1] = amdgpu_ring_get_wptr(ring) & ring->buf_mask; + p = early[0]; if (early[0] <= early[1]) - size = (early[1] - early[0]); + avail_dw = early[1] - early[0]; else - size = ring->ring_size - (early[0] - early[1]); + avail_dw = ring->buf_mask + 1 - (early[0] - early[1]); - while (size) { + start_dw = (*pos > 12) ? ((*pos - 12) >> 2) : 0; + if (start_dw >= avail_dw) + goto out; + + p = (p + start_dw) & ring->ptr_mask; + avail_dw -= start_dw; + read_dw = min_t(u32, avail_dw, size >> 2); + + while (read_dw) { if (p == early[1]) goto out; @@ -619,9 +631,10 @@ static ssize_t amdgpu_debugfs_ring_read(struct file *f, char __user *buf, buf += 4; result += 4; - size--; + read_dw--; p++; p &= ring->ptr_mask; + *pos += 4; } } From 5d08559c910cc37673b965a0d4e8d004444d0332 Mon Sep 17 00:00:00 2001 From: Jesse Zhang Date: Fri, 3 Apr 2026 15:58:31 +0800 Subject: [PATCH 7/7] drm/amdgpu/gfx_v12_0: set gfx.rs64_enable from PFP header on GFX12 gfx_v12_0_init_microcode() always loads RS64 CP ucode but never set adev->gfx.rs64_enable, so it stayed false and code that branches on it (e.g. MEC pipe reset) used the legacy CP_MEC_CNTL path incorrectly. Match GFX11: derive RS64 mode from the PFP firmware header (v2.0) via amdgpu_ucode_hdr_version(). Log at debug when RS64 is enabled. Reviewed-by: Alex Deucher Signed-off-by: Jesse Zhang Signed-off-by: Alex Deucher (cherry picked from commit b03d53598b0d2048e8fa7303b8d0784768ec4fa6) --- drivers/gpu/drm/amd/amdgpu/gfx_v12_0.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v12_0.c b/drivers/gpu/drm/amd/amdgpu/gfx_v12_0.c index 0e0b1e5b88fc..c35372e21261 100644 --- a/drivers/gpu/drm/amd/amdgpu/gfx_v12_0.c +++ b/drivers/gpu/drm/amd/amdgpu/gfx_v12_0.c @@ -602,6 +602,13 @@ static int gfx_v12_0_init_microcode(struct amdgpu_device *adev) "amdgpu/%s_pfp.bin", ucode_prefix); if (err) goto out; + + adev->gfx.rs64_enable = amdgpu_ucode_hdr_version( + (union amdgpu_firmware_header *) + adev->gfx.pfp_fw->data, 2, 0); + if (adev->gfx.rs64_enable) + dev_dbg(adev->dev, "CP RS64 enable\n"); + amdgpu_gfx_cp_init_microcode(adev, AMDGPU_UCODE_ID_CP_RS64_PFP); amdgpu_gfx_cp_init_microcode(adev, AMDGPU_UCODE_ID_CP_RS64_PFP_P0_STACK);