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%3Ba=su...
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