Patch "x86/mm: Change the leave_mm() condition for local TLB flushes" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    x86/mm: Change the leave_mm() condition for local TLB flushes

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     x86-mm-change-the-leave_mm-condition-for-local-tlb-flushes.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 59f537c1dea04287165bb11407921e095250dc80 Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <luto@kernel.org>
Date: Sun, 28 May 2017 10:00:11 -0700
Subject: x86/mm: Change the leave_mm() condition for local TLB flushes

From: Andy Lutomirski <luto@kernel.org>

commit 59f537c1dea04287165bb11407921e095250dc80 upstream.

On a remote TLB flush, we leave_mm() if we're TLBSTATE_LAZY.  For a
local flush_tlb_mm_range(), we leave_mm() if !current->mm.  These
are approximately the same condition -- the scheduler sets lazy TLB
mode when switching to a thread with no mm.

I'm about to merge the local and remote flush code, but for ease of
verifying and bisecting the patch, I want the local and remote flush
behavior to match first.  This patch changes the local code to match
the remote code.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Acked-by: Rik van Riel <riel@redhat.com>
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>
Signed-off-by: Eduardo Valentin <eduval@amazon.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/x86/mm/tlb.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -328,7 +328,7 @@ void flush_tlb_mm_range(struct mm_struct
 		goto out;
 	}
 
-	if (!current->mm) {
+	if (this_cpu_read(cpu_tlbstate.state) != TLBSTATE_OK) {
 		leave_mm(smp_processor_id());
 
 		/* Synchronize with switch_mm. */


Patches currently in stable-queue which might be from luto@kernel.org are

queue-4.9/x86-mm-refactor-flush_tlb_mm_range-to-merge-local-and-remote-cases.patch
queue-4.9/x86-mm-pass-flush_tlb_info-to-flush_tlb_others-etc.patch
queue-4.9/x86-mm-rework-lazy-tlb-to-track-the-actual-loaded-mm.patch
queue-4.9/x86-mm-kvm-teach-kvm-s-vmx-code-that-cr3-isn-t-a-constant.patch
queue-4.9/x86-mm-use-new-merged-flush-logic-in-arch_tlbbatch_flush.patch
queue-4.9/x86-kvm-vmx-simplify-segment_base.patch
queue-4.9/x86-entry-unwind-create-stack-frames-for-saved-interrupt-registers.patch
queue-4.9/x86-mm-reduce-indentation-in-flush_tlb_func.patch
queue-4.9/x86-mm-remove-the-up-asm-tlbflush.h-code-always-use-the-formerly-smp-code.patch
queue-4.9/x86-mm-reimplement-flush_tlb_page-using-flush_tlb_mm_range.patch
queue-4.9/mm-x86-mm-make-the-batched-unmap-tlb-flush-api-more-generic.patch
queue-4.9/x86-kvm-vmx-defer-tr-reload-after-vm-exit.patch
queue-4.9/x86-mm-change-the-leave_mm-condition-for-local-tlb-flushes.patch
queue-4.9/x86-mm-be-more-consistent-wrt-page_shift-vs-page_size-in-tlb-flush-code.patch