From: Andy Lutomirski <luto@kernel.org>
Date: Sun, 28 May 2017 10:00:13 -0700
Subject: x86/mm: Use new merged flush logic in arch_tlbbatch_flush()
Git-commit: 3f79e4c7c9c2f5c30751ea5c8dd9fd1d56b81947
Patch-mainline: v4.13-rc1
References: bsc#1068032 CVE-2017-5754

Now there's only one copy of the local tlb flush logic for
non-kernel pages on SMP kernels.

The only functional change is that arch_tlbbatch_flush() will now
leave_mm() on the local CPU if that CPU is in the batch and is in
TLBSTATE_LAZY mode.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Borislav Petkov <bp@suse.de>
---
 arch/x86/mm/tlb.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
index 12b8812e8926..c03b4a0ce58c 100644
--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -382,12 +382,8 @@ void arch_tlbbatch_flush(struct arch_tlbflush_unmap_batch *batch)
 
 	int cpu = get_cpu();
 
-	if (cpumask_test_cpu(cpu, &batch->cpumask)) {
-		count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ALL);
-		local_flush_tlb();
-		trace_tlb_flush(TLB_LOCAL_SHOOTDOWN, TLB_FLUSH_ALL);
-	}
-
+	if (cpumask_test_cpu(cpu, &batch->cpumask))
+		flush_tlb_func_local(&info, TLB_LOCAL_SHOOTDOWN);
 	if (cpumask_any_but(&batch->cpumask, cpu) < nr_cpu_ids)
 		flush_tlb_others(&batch->cpumask, &info);
 	cpumask_clear(&batch->cpumask);