From: Boris Brezillon Date: Fri, 5 Feb 2021 11:17:56 +0000 (+0100) Subject: drm/panfrost: Don't try to map pages that are already mapped X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=f45da8204ff1707c529a8769f5467ff16f504b26;p=linux.git drm/panfrost: Don't try to map pages that are already mapped 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 --- diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index 904d634508626..21e552d1ac71a 100644 --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c @@ -488,8 +488,14 @@ 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); @@ -522,6 +528,7 @@ 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;