]> git.baikalelectronics.ru Git - kernel.git/commit
powerpc/iommu: Do not call PageTransHuge() on tail pages
authorAlexey Kardashevskiy <aik@ozlabs.ru>
Tue, 11 Apr 2017 07:54:57 +0000 (17:54 +1000)
committerMichael Ellerman <mpe@ellerman.id.au>
Wed, 19 Apr 2017 10:00:20 +0000 (20:00 +1000)
commit554873c89f7c898e897af55ddda1b13736d0b699
tree81e76f9496a2517efc25f8ca0dd631c4f8f94b41
parent7bff8c37767ef14dca58f0269e91648d5058895a
powerpc/iommu: Do not call PageTransHuge() on tail pages

The CMA pages migration code does not support compound pages at
the moment so it performs few tests before proceeding to actual page
migration.

One of the tests - PageTransHuge() - has VM_BUG_ON_PAGE(PageTail()) as
it is designed to be called on head pages only. Since we also test for
PageCompound(), and it contains PageTail() and PageHead(), we can
simplify the check by leaving just PageCompound() and therefore avoid
possible VM_BUG_ON_PAGE.

Fixes: adc605ce14b2 ("KVM: PPC: Book3S HV: Migrate pinned pages out of CMA")
Cc: stable@vger.kernel.org # v4.9+
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/mm/mmu_context_iommu.c