From 1986a3b022bee7ad34d0c539b32a81575bf3c9a3 Mon Sep 17 00:00:00 2001 From: Felix Kuehling Date: Tue, 7 May 2019 17:46:14 -0400 Subject: [PATCH] drm/amdgpu: Improve error handling for HMM Use unsigned long for number of pages. Check that pfns are valid after hmm_vma_fault. If they are not, return an error instead of continuing with invalid page pointers and PTEs. Signed-off-by: Felix Kuehling Reviewed-by: Philip Yang Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c index b25922e3d1ed..7138dc1dd1f4 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -734,10 +734,11 @@ int amdgpu_ttm_tt_get_user_pages(struct ttm_tt *ttm, struct page **pages) struct mm_struct *mm = gtt->usertask->mm; unsigned long start = gtt->userptr; unsigned long end = start + ttm->num_pages * PAGE_SIZE; - struct hmm_range *ranges; struct vm_area_struct *vma = NULL, *vmas[MAX_NR_VMAS]; + struct hmm_range *ranges; + unsigned long nr_pages, i; uint64_t *pfns, f; - int r = 0, i, nr_pages; + int r = 0; if (!mm) /* Happens during process shutdown */ return -ESRCH; @@ -813,8 +814,14 @@ int amdgpu_ttm_tt_get_user_pages(struct ttm_tt *ttm, struct page **pages) up_read(&mm->mmap_sem); - for (i = 0; i < ttm->num_pages; i++) + for (i = 0; i < ttm->num_pages; i++) { pages[i] = hmm_pfn_to_page(&ranges[0], pfns[i]); + if (!pages[i]) { + pr_err("Page fault failed for pfn[%lu] = 0x%llx\n", + i, pfns[i]); + goto out_invalid_pfn; + } + } gtt->ranges = ranges; return 0; @@ -827,6 +834,13 @@ out: up_read(&mm->mmap_sem); return r; + +out_invalid_pfn: + for (i = 0; i < gtt->nr_ranges; i++) + hmm_vma_range_done(&ranges[i]); + kvfree(pfns); + kvfree(ranges); + return -ENOMEM; } /** @@ -871,7 +885,7 @@ bool amdgpu_ttm_tt_get_user_pages_done(struct ttm_tt *ttm) */ void amdgpu_ttm_tt_set_user_pages(struct ttm_tt *ttm, struct page **pages) { - unsigned i; + unsigned long i; for (i = 0; i < ttm->num_pages; ++i) ttm->pages[i] = pages ? pages[i] : NULL; -- 2.20.1