[PATCH 0/1] mm/debug_vm_pgtable: fix alignment for pmd/pud_advanced_tests()

Gerald Schaefer
2021-05-25T13:01:47Z

We sometimes see a "BUG task_struct (Not tainted): Padding overwritten"
on s390, directly after running debug_vm_pgtable. This is because of
wrong vaddr alignment in pmd/pud_advanced_tests(), leading to memory
corruption at least on s390, see patch description.

At first glance, other architectures do not seem to care about vaddr in
their xxx_get_and_clear() implementations, so they should not be affected.
One exception is sparc, where the addr is passed over to some tlb_batch
code, but I'm not sure what implication the wrongly aligned vaddr would
have in this case.

Also adding linux-arch, just to make sure.

Gerald Schaefer (1):
mm/debug_vm_pgtable: fix alignment for pmd/pud_advanced_tests()

mm/debug_vm_pgtable.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

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2.25.1