6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Thomas Hellström thomas.hellstrom@linux.intel.com
[ Upstream commit 9106713bd2ab0cacd380cda0d3f0219f2e488086 ]
The assert incorrectly checks the total length processed which can in fact be greater than the number of pages. Fix.
Fixes: 0a98219bcc96 ("drm/xe/hmm: Don't dereference struct page pointers without notifier lock") Cc: Matthew Auld matthew.auld@intel.com Cc: Matthew Brost matthew.brost@intel.com Signed-off-by: Thomas Hellström thomas.hellstrom@linux.intel.com Reviewed-by: Matthew Auld matthew.auld@intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20250307100109.21397-1-thomas.... (cherry picked from commit 70e5043ba85eae199b232e39921abd706b5c1fa4) Signed-off-by: Rodrigo Vivi rodrigo.vivi@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/xe/xe_hmm.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/xe/xe_hmm.c b/drivers/gpu/drm/xe/xe_hmm.c index d7a9408b3a97c..f6bc4f29d7538 100644 --- a/drivers/gpu/drm/xe/xe_hmm.c +++ b/drivers/gpu/drm/xe/xe_hmm.c @@ -138,13 +138,17 @@ static int xe_build_sg(struct xe_device *xe, struct hmm_range *range, i += size;
if (unlikely(j == st->nents - 1)) { + xe_assert(xe, i >= npages); if (i > npages) size -= (i - npages); + sg_mark_end(sgl); + } else { + xe_assert(xe, i < npages); } + sg_set_page(sgl, page, size << PAGE_SHIFT, 0); } - xe_assert(xe, i == npages);
return dma_map_sgtable(dev, st, write ? DMA_BIDIRECTIONAL : DMA_TO_DEVICE, DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_NO_KERNEL_MAPPING);