drm/i915: Mark contents as dirty on a write fault

Since dropping the set-to-gtt-domain in commit a679f58d05 ("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: a679f58d05 ("drm/i915: Flush pages on acquisition")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: <stable@vger.kernel.org> # v5.2+
Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190920121821.7223-1-chris@chris-wilson.co.uk
(cherry picked from commit 5028851cdf)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
This commit is contained in:
Chris Wilson 2019-09-20 13:18:21 +01:00 committed by Rodrigo Vivi
parent 7d0eb51dd9
commit b925708f28
1 changed files with 5 additions and 1 deletions

View File

@ -316,7 +316,11 @@ vm_fault_t i915_gem_fault(struct vm_fault *vmf)
intel_wakeref_auto(&i915->ggtt.userfault_wakeref,
msecs_to_jiffies_timeout(CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND));
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);