From 1fc9af813b25e146d3607669247d0f970f5a87c3 Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Fri, 5 Jan 2024 21:46:11 +0300 Subject: [PATCH] drm/panfrost: Fix the error path in panfrost_mmu_map_fault_addr() Subject: [PATCH] drm/panfrost: Fix the error path in panfrost_mmu_map_fault_addr() If some the pages or sgt allocation failed, we shouldn't release the pages ref we got earlier, otherwise we will end up with unbalanced get/put_pages() calls. We should instead leave everything in place and let the BO release function deal with extra cleanup when the object is destroyed, or let the fault handler try again next time it's called. Fixes: 187d2929206e ("drm/panfrost: Add support for GPU heap allocations") Cc: Reviewed-by: Steven Price Reviewed-by: AngeloGioacchino Del Regno Signed-off-by: Boris Brezillon Co-developed-by: Dmitry Osipenko Signed-off-by: Dmitry Osipenko Link: https://patchwork.freedesktop.org/patch/msgid/20240105184624.508603-18-dmitry.osipenko@collabora.com --- drivers/gpu/drm/panfrost/panfrost_mmu.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index f38385fe76bb..b91019cd5acb 100644 --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c @@ -502,11 +502,18 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as, mapping_set_unevictable(mapping); for (i = page_offset; i < page_offset + NUM_FAULT_PAGES; i++) { + /* Can happen if the last fault only partially filled this + * section of the pages array before failing. In that case + * we skip already filled pages. + */ + if (pages[i]) + continue; + pages[i] = shmem_read_mapping_page(mapping, i); if (IS_ERR(pages[i])) { ret = PTR_ERR(pages[i]); pages[i] = NULL; - goto err_pages; + goto err_unlock; } } @@ -514,7 +521,7 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as, ret = sg_alloc_table_from_pages(sgt, pages + page_offset, NUM_FAULT_PAGES, 0, SZ_2M, GFP_KERNEL); if (ret) - goto err_pages; + goto err_unlock; ret = dma_map_sgtable(pfdev->dev, sgt, DMA_BIDIRECTIONAL, 0); if (ret) @@ -537,8 +544,6 @@ out: err_map: sg_free_table(sgt); -err_pages: - drm_gem_shmem_put_pages(&bo->base); err_unlock: dma_resv_unlock(obj->resv); err_bo: