Hugh Dickins 2f10f1a788 powerpc/mm: fix _PAGE_SWP_SOFT_DIRTY breaking swapoff ... Swapoff after swapping hangs on the G5, when CONFIG_CHECKPOINT_RESTORE=y but CONFIG_MEM_SOFT_DIRTY is not set. That's because the non-zero _PAGE_SWP_SOFT_DIRTY bit, added by CONFIG_HAVE_ARCH_SOFT_DIRTY=y, is not discounted when CONFIG_MEM_SOFT_DIRTY is not set: so swap ptes cannot be recognized. (I suspect that the peculiar dependence of HAVE_ARCH_SOFT_DIRTY on CHECKPOINT_RESTORE in arch/powerpc/Kconfig comes from an incomplete attempt to solve this problem.) It's true that the relationship between CONFIG_HAVE_ARCH_SOFT_DIRTY and and CONFIG_MEM_SOFT_DIRTY is too confusing, and it's true that swapoff should be made more robust; but nevertheless, fix up the powerpc ifdefs as x86_64 and s390 (which met the same problem) have them, defining the bits as 0 if CONFIG_MEM_SOFT_DIRTY is not set. Fixes: 7207f43665 ("powerpc/mm: Add page soft dirty tracking") Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: Cyrill Gorcunov <gorcunov@openvz.org> Acked-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>		2016-01-12 11:03:53 +11:00
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32	powerpc/mm: Move PTE bits from generic functions to hash64 functions.	2015-12-14 15:19:08 +11:00
64	powerpc/mm: fix _PAGE_SWP_SOFT_DIRTY breaking swapoff	2016-01-12 11:03:53 +11:00
pgtable.h	powerpc/mm: Move PTE bits from generic functions to hash64 functions.	2015-12-14 15:19:08 +11:00