From: Matthew Auld <matthew.auld@xxxxxxxxx> commit f90daa975911961b65070ec72bd7dd8d448f9ef7 upstream. We need to iterate over the original entries here for the sg_table, pulling out the struct page for each one, to be remapped. However currently this incorrectly iterates over the final dma mapped entries, which is likely just one gigantic sg entry if the iommu is enabled, leading to us only mapping the first struct page (and any physically contiguous pages following it), even if there is potentially lots more data to follow. Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/7306 Fixes: 1286ff739773 ("i915: add dmabuf/prime buffer sharing support.") Signed-off-by: Matthew Auld <matthew.auld@xxxxxxxxx> Cc: Lionel Landwerlin <lionel.g.landwerlin@xxxxxxxxx> Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxxxxxxx> Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Cc: Michael J. Ruhl <michael.j.ruhl@xxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> # v3.5+ Reviewed-by: Michael J. Ruhl <michael.j.ruhl@xxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20221028155029.494736-1-matthew.auld@xxxxxxxxx (cherry picked from commit 28d52f99bbca7227008cf580c9194c9b3516968e) Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c @@ -36,13 +36,13 @@ static struct sg_table *i915_gem_map_dma goto err_unpin_pages; } - ret = sg_alloc_table(st, obj->mm.pages->nents, GFP_KERNEL); + ret = sg_alloc_table(st, obj->mm.pages->orig_nents, GFP_KERNEL); if (ret) goto err_free; src = obj->mm.pages->sgl; dst = st->sgl; - for (i = 0; i < obj->mm.pages->nents; i++) { + for (i = 0; i < obj->mm.pages->orig_nents; i++) { sg_set_page(dst, sg_page(src), src->length, 0); dst = sg_next(dst); src = sg_next(src);
