Commit d64c8053 authored by Mostafa Saleh's avatar Mostafa Saleh Committed by Will Deacon
Browse files

iommu/io-pgtable-arm: Add self test for the last page in the IAS 



Add a case in the selftests that can detect some bugs with concatenated
page tables, where it maps the biggest supported page size at the end of
the IAS, this test would fail without the previous fix.

Signed-off-by: default avatarMostafa Saleh <smostafa@google.com>
Link: https://lore.kernel.org/r/20241024162516.2005652-3-smostafa@google.com


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent d71fa842

drivers/iommu/io-pgtable-arm.c

+17 −0
Original line number Diff line number Diff line
@@ -1394,6 +1394,23 @@ static int __init arm_lpae_run_tests(struct io_pgtable_cfg *cfg) 
			iova += SZ_1G;

		}



		/*

		 * Map/unmap the last largest supported page of the IAS, this can

		 * trigger corner cases in the concatednated page tables.

		 */

		mapped = 0;

		size = 1UL << __fls(cfg->pgsize_bitmap);

		iova = (1UL << cfg->ias) - size;

		if (ops->map_pages(ops, iova, iova, size, 1,

				   IOMMU_READ | IOMMU_WRITE |

				   IOMMU_NOEXEC | IOMMU_CACHE,

				   GFP_KERNEL, &mapped))

			return __FAIL(ops, i);

		if (mapped != size)

			return __FAIL(ops, i);

		if (ops->unmap_pages(ops, iova, size, 1, NULL) != size)

			return __FAIL(ops, i);



		free_io_pgtable_ops(ops);

	}