On Mon, Jan 27, 2025 at 03:43:32PM -0500, Brian Geffon wrote:
When converting to folios the cleanup path of shmem_get_pages() was missed. When a DMA remap fails and the max segment size is greater than PAGE_SIZE it will attempt to retry the remap with a PAGE_SIZEd segment size. The cleanup code isn't properly using the folio apis and as a result isn't handling compound pages correctly.
v2 -> v3: (Ville) Just use shmem_sg_free_table() as-is in the failure path of shmem_get_pages(). shmem_sg_free_table() will clear mapping unevictable but it will be reset when it retries in shmem_sg_alloc_table().
v1 -> v2: (Ville) Fixed locations where we were not clearing mapping unevictable.
Cc: stable@vger.kernel.org Cc: Ville Syrjala ville.syrjala@linux.intel.com Cc: Vidya Srinivas vidya.srinivas@intel.com Link: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/13487 Link: https://lore.kernel.org/lkml/20250116135636.410164-1-bgeffon@google.com/ Fixes: 0b62af28f249 ("i915: convert shmem_sg_free_table() to use a folio_batch") Signed-off-by: Brian Geffon bgeffon@google.com Suggested-by: Tomasz Figa tfiga@google.com
Thanks. Pushed to drm-intel-gt-next.
drivers/gpu/drm/i915/gem/i915_gem_shmem.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c index fe69f2c8527d..ae3343c81a64 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c @@ -209,8 +209,6 @@ static int shmem_get_pages(struct drm_i915_gem_object *obj) struct address_space *mapping = obj->base.filp->f_mapping; unsigned int max_segment = i915_sg_segment_size(i915->drm.dev); struct sg_table *st;
- struct sgt_iter sgt_iter;
- struct page *page; int ret;
/* @@ -239,9 +237,7 @@ static int shmem_get_pages(struct drm_i915_gem_object *obj) * for PAGE_SIZE chunks instead may be helpful. */ if (max_segment > PAGE_SIZE) {
for_each_sgt_page(page, sgt_iter, st)put_page(page);sg_free_table(st);
shmem_sg_free_table(st, mapping, false, false); kfree(st);max_segment = PAGE_SIZE; -- 2.48.1.262.g85cc9f2d1e-goog