| From f45da8204ff1707c529a8769f5467ff16f504b26 Mon Sep 17 00:00:00 2001 |
| From: Boris Brezillon <boris.brezillon@collabora.com> |
| Date: Fri, 5 Feb 2021 12:17:56 +0100 |
| Subject: drm/panfrost: Don't try to map pages that are already mapped |
| |
| From: Boris Brezillon <boris.brezillon@collabora.com> |
| |
| 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: <stable@vger.kernel.org> |
| Fixes: 187d2929206e ("drm/panfrost: Add support for GPU heap allocations") |
| Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com> |
| Reviewed-by: Steven Price <steven.price@arm.com> |
| Link: https://patchwork.freedesktop.org/patch/msgid/20210205111757.585248-3-boris.brezillon@collabora.com |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/gpu/drm/panfrost/panfrost_mmu.c | 9 ++++++++- |
| 1 file changed, 8 insertions(+), 1 deletion(-) |
| |
| --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c |
| +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c |
| @@ -495,8 +495,14 @@ static int panfrost_mmu_map_fault_addr(s |
| } |
| 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(s |
| |
| dev_dbg(pfdev->dev, "mapped page fault @ AS%d %llx", as, addr); |
| |
| +out: |
| panfrost_gem_mapping_put(bomapping); |
| |
| return 0; |