From 7a78f4f0497f903756183f8b227f6fddaba8cdb0 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 20 Sep 2019 13:18:21 +0100 Subject: [PATCH] drm/i915: Mark contents as dirty on a write fault MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Since dropping the set-to-gtt-domain in commit a679f58d0510 ("drm/i915: Flush pages on acquisition"), we no longer mark the contents as dirty on a write fault. This has the issue of us then not marking the pages as dirty on releasing the buffer, which means the contents are not written out to the swap device (should we ever pick that buffer as a victim). Notably, this is visible in the dumb buffer interface used for cursors. Having updated the cursor contents via mmap, and swapped away, if the shrinker should evict the old cursor, upon next reuse, the cursor would be invisible. E.g. echo 80 > /proc/sys/kernel/sysrq ; echo f > /proc/sysrq-trigger Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111541 Fixes: a679f58d0510 ("drm/i915: Flush pages on acquisition") Signed-off-by: Chris Wilson Cc: Matthew Auld Cc: Ville Syrjälä Cc: # v5.2+ Reviewed-by: Matthew Auld Link: https://patchwork.freedesktop.org/patch/msgid/20190920121821.7223-1-chris@chris-wilson.co.uk (cherry picked from commit 5028851cdfdf78dc22eacbc44a0ab0b3f599ee4a) Signed-off-by: Rodrigo Vivi --- drivers/gpu/drm/i915/gem/i915_gem_mman.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c index 39a661927d8e..c201289039fe 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c @@ -317,7 +317,11 @@ vm_fault_t i915_gem_fault(struct vm_fault *vmf) msecs_to_jiffies_timeout(CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND)); GEM_BUG_ON(!obj->userfault_count); - i915_vma_set_ggtt_write(vma); + if (write) { + GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj)); + i915_vma_set_ggtt_write(vma); + obj->mm.dirty = true; + } err_fence: i915_vma_unpin_fence(vma); -- 2.21.0