On Tue, Apr 05, 2016 at 01:12:34PM +0300, Kirill A. Shutemov wrote: > Andrea has found[1] a race condition on MMU-gather based TLB flush vs > split_huge_page() or shrinker which frees huge zero under us (patch 1/2 > and 2/2 respectively). > > With new THP refcounting, we don't need patch 1/2: mmu_gather keeps the > page pinned until flush is complete and the pin prevents the page from > being split under us. > > We still need patch 2/2. This is simplified version of Andrea's patch. > We don't need fancy encoding. > > [1] http://lkml.kernel.org/r/1447938052-22165-1-git-send-email-aarcange@xxxxxxxxxx > > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> > Reported-by: Andrea Arcangeli <aarcange@xxxxxxxxxx> > --- > v2: > - fix build for !THP; > - typos; > --- > include/linux/huge_mm.h | 5 +++++ > mm/huge_memory.c | 6 +++--- > mm/swap.c | 5 +++++ > 3 files changed, 13 insertions(+), 3 deletions(-) Reviewed-by: Andrea Arcangeli <aarcange@xxxxxxxxxx> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>