From: Nadav Amit <[email protected]> fullmm in mmu_gather is supposed to indicate that the mm is torn-down (e.g., on process exit) and can therefore allow certain optimizations. However, tlb_finish_mmu() sets fullmm, when in fact it want to say that the TLB should be fully flushed.
Change tlb_finish_mmu() to set need_flush_all and check this flag in tlb_flush_mmu_tlbonly() when deciding whether a flush is needed. Signed-off-by: Nadav Amit <[email protected]> Cc: Andrea Arcangeli <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Will Deacon <[email protected]> Cc: Yu Zhao <[email protected]> Cc: Nick Piggin <[email protected]> Cc: [email protected] --- include/asm-generic/tlb.h | 2 +- mm/mmu_gather.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h index 2c68a545ffa7..eea113323468 100644 --- a/include/asm-generic/tlb.h +++ b/include/asm-generic/tlb.h @@ -420,7 +420,7 @@ static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb) * these bits. */ if (!(tlb->freed_tables || tlb->cleared_ptes || tlb->cleared_pmds || - tlb->cleared_puds || tlb->cleared_p4ds)) + tlb->cleared_puds || tlb->cleared_p4ds || tlb->need_flush_all)) return; tlb_flush(tlb); diff --git a/mm/mmu_gather.c b/mm/mmu_gather.c index 0dc7149b0c61..5a659d4e59eb 100644 --- a/mm/mmu_gather.c +++ b/mm/mmu_gather.c @@ -323,7 +323,7 @@ void tlb_finish_mmu(struct mmu_gather *tlb) * On x86 non-fullmm doesn't yield significant difference * against fullmm. */ - tlb->fullmm = 1; + tlb->need_flush_all = 1; __tlb_reset_range(tlb); tlb->freed_tables = 1; } -- 2.25.1
