From 1753f5f81ab60a553287f9ee659a6ac363adf8d7 Mon Sep 17 00:00:00 2001 From: Tvrtko Ursulin Date: Mon, 23 Feb 2026 12:41:31 +0000 Subject: [PATCH] drm/amdgpu/userq: Do not allow userspace to trivially triger kernel warnings MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit 7b7d7693a55d606d700beb9549c9f7f0e5d9c24f ] Userspace can either deliberately pass in the too small num_fences, or the required number can legitimately grow between the two calls to the userq wait ioctl. In both cases we do not want the emit the kernel warning backtrace since nothing is wrong with the kernel and userspace will simply get an errno reported back. So lets simply drop the WARN_ONs. Reviewed-by: Alex Deucher Signed-off-by: Tvrtko Ursulin Fixes: a292fdecd728 ("drm/amdgpu: Implement userqueue signal/wait IOCTL") Cc: Arunpravin Paneer Selvam Cc: Christian König Cc: Alex Deucher Reviewed-by: Christian König Signed-off-by: Alex Deucher (cherry picked from commit 2c333ea579de6cc20ea7bc50e9595ef72863e65c) Signed-off-by: Sasha Levin --- drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c index 5c181ac75d54..ead153897445 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_userq_fence.c @@ -829,7 +829,7 @@ int amdgpu_userq_wait_ioctl(struct drm_device *dev, void *data, dma_resv_for_each_fence(&resv_cursor, gobj_read[i]->resv, DMA_RESV_USAGE_READ, fence) { - if (WARN_ON_ONCE(num_fences >= wait_info->num_fences)) { + if (num_fences >= wait_info->num_fences) { r = -EINVAL; goto free_fences; } @@ -846,7 +846,7 @@ int amdgpu_userq_wait_ioctl(struct drm_device *dev, void *data, dma_resv_for_each_fence(&resv_cursor, gobj_write[i]->resv, DMA_RESV_USAGE_WRITE, fence) { - if (WARN_ON_ONCE(num_fences >= wait_info->num_fences)) { + if (num_fences >= wait_info->num_fences) { r = -EINVAL; goto free_fences; } @@ -870,7 +870,7 @@ int amdgpu_userq_wait_ioctl(struct drm_device *dev, void *data, goto free_fences; dma_fence_unwrap_for_each(f, &iter, fence) { - if (WARN_ON_ONCE(num_fences >= wait_info->num_fences)) { + if (num_fences >= wait_info->num_fences) { r = -EINVAL; goto free_fences; } @@ -894,7 +894,7 @@ int amdgpu_userq_wait_ioctl(struct drm_device *dev, void *data, if (r) goto free_fences; - if (WARN_ON_ONCE(num_fences >= wait_info->num_fences)) { + if (num_fences >= wait_info->num_fences) { r = -EINVAL; goto free_fences; }