From c1d827d62f71eb6eaa0b2ffad4d893faa99e4c87 Mon Sep 17 00:00:00 2001 From: Tom St Denis Date: Fri, 14 Jun 2019 11:47:21 -0400 Subject: [PATCH] drm/amd/amdgpu: cast mem->num_pages to 64-bits when shifting (v2) On 32-bit hosts mem->num_pages is 32-bits and can overflow when shifted. Add a cast to avoid this. (v2): Style fix. Signed-off-by: Tom St Denis Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c index c963ad8..1150e34 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c @@ -276,7 +276,7 @@ static int amdgpu_vram_mgr_new(struct ttm_mem_type_manager *man, struct drm_mm_node *nodes; enum drm_mm_insert_mode mode; unsigned long lpfn, num_nodes, pages_per_node, pages_left; - uint64_t vis_usage = 0; + uint64_t vis_usage = 0, mem_bytes; unsigned i; int r; @@ -285,8 +285,9 @@ static int amdgpu_vram_mgr_new(struct ttm_mem_type_manager *man, lpfn = man->size; /* bail out quickly if there's likely not enough VRAM for this BO */ - if (atomic64_add_return(mem->num_pages << PAGE_SHIFT, &mgr->usage) > adev->gmc.mc_vram_size) { - atomic64_sub(mem->num_pages << PAGE_SHIFT, &mgr->usage); + mem_bytes = (u64)mem->num_pages << PAGE_SHIFT; + if (atomic64_add_return(mem_bytes, &mgr->usage) > adev->gmc.mc_vram_size) { + atomic64_sub(mem_bytes, &mgr->usage); mem->mm_node = NULL; return 0; } @@ -308,7 +309,7 @@ static int amdgpu_vram_mgr_new(struct ttm_mem_type_manager *man, nodes = kvmalloc_array((uint32_t)num_nodes, sizeof(*nodes), GFP_KERNEL | __GFP_ZERO); if (!nodes) { - atomic64_sub(mem->num_pages << PAGE_SHIFT, &mgr->usage); + atomic64_sub(mem_bytes, &mgr->usage); return -ENOMEM; } -- 2.7.4