From: Chris Wilson chris@chris-wilson.co.uk
commit 036867e93ebf4d7e70eba6a8c72db74ee3760bc3 upstream.
When instantiating a tiled object on an L-shaped memory machine, we mark the object as unshrinkable to prevent the shrinker from trying to swap out the pages. We have to do this as we do not know the swizzling on the individual pages, and so the data will be scrambled across swap out/in.
Not only do we need to move the object off the shrinker list, we need to mark the object with shrink_pin so that the counter is consistent across calls to madvise.
v2: in the madvise ioctl we need to check if the object is currently shrinkable/purgeable, not if the object type supports shrinking
Fixes: 0175969e489a ("drm/i915/gem: Use shrinkable status for unknown swizzle quirks") Reported-by: Ville Syrjälä ville.syrjala@linux.intel.com Tested-by: Ville Syrjälä ville.syrjala@linux.intel.com Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Reviewed-by: Matthew Auld matthew.auld@intel.com Signed-off-by: Matthew Auld matthew.auld@intel.com Cc: stable@vger.kernel.org # v5.12+ Link: https://patchwork.freedesktop.org/patch/msgid/20210517084640.18862-1-matthew... (cherry picked from commit 8777d17b68dcfbfbd4d524f444adefae56f41225) Signed-off-by: Jani Nikula jani.nikula@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/i915/gem/i915_gem_pages.c | 2 ++ drivers/gpu/drm/i915/i915_gem.c | 11 +++++------ 2 files changed, 7 insertions(+), 6 deletions(-)
--- a/drivers/gpu/drm/i915/gem/i915_gem_pages.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_pages.c @@ -63,6 +63,8 @@ void __i915_gem_object_set_pages(struct i915->quirks & QUIRK_PIN_SWIZZLED_PAGES) { GEM_BUG_ON(i915_gem_object_has_tiling_quirk(obj)); i915_gem_object_set_tiling_quirk(obj); + GEM_BUG_ON(!list_empty(&obj->mm.link)); + atomic_inc(&obj->mm.shrink_pin); shrinkable = false; }
--- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -972,12 +972,11 @@ i915_gem_madvise_ioctl(struct drm_device obj->mm.madv = args->madv;
if (i915_gem_object_has_pages(obj)) { - struct list_head *list; + unsigned long flags;
- if (i915_gem_object_is_shrinkable(obj)) { - unsigned long flags; - - spin_lock_irqsave(&i915->mm.obj_lock, flags); + spin_lock_irqsave(&i915->mm.obj_lock, flags); + if (!list_empty(&obj->mm.link)) { + struct list_head *list;
if (obj->mm.madv != I915_MADV_WILLNEED) list = &i915->mm.purge_list; @@ -985,8 +984,8 @@ i915_gem_madvise_ioctl(struct drm_device list = &i915->mm.shrink_list; list_move_tail(&obj->mm.link, list);
- spin_unlock_irqrestore(&i915->mm.obj_lock, flags); } + spin_unlock_irqrestore(&i915->mm.obj_lock, flags); }
/* if the object is no longer attached, discard its backing storage */