From 4aea3ddac00a5b6f106416ef849af252dca79cd3 Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Fri, 5 Feb 2021 12:17:56 +0100 Subject: [PATCH] drm/panfrost: Don't try to map pages that are already mapped commit f45da8204ff1707c529a8769f5467ff16f504b26 upstream. We allocate 2MB chunks at a time, so it might appear that a page fault has already been handled by a previous page fault when we reach panfrost_mmu_map_fault_addr(). Bail out in that case to avoid mapping the same area twice. Cc: Fixes: 187d2929206e ("drm/panfrost: Add support for GPU heap allocations") Signed-off-by: Boris Brezillon Reviewed-by: Steven Price Link: https://patchwork.freedesktop.org/patch/msgid/20210205111757.585248-3-boris.brezillon@collabora.com Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/panfrost/panfrost_mmu.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index fee962ab46969..bfd503d220881 100644 --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c @@ -494,8 +494,14 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as, } bo->base.pages = pages; bo->base.pages_use_count = 1; - } else + } else { pages = bo->base.pages; + if (pages[page_offset]) { + /* Pages are already mapped, bail out. */ + mutex_unlock(&bo->base.pages_lock); + goto out; + } + } mapping = bo->base.base.filp->f_mapping; mapping_set_unevictable(mapping); @@ -529,6 +535,7 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as, dev_dbg(pfdev->dev, "mapped page fault @ AS%d %llx", as, addr); +out: panfrost_gem_mapping_put(bomapping); return 0; -- 2.47.3