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

    x86/kasan: Flush TLBs after switching CR3

to the 4.1-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-kasan-flush-tlbs-after-switching-cr3.patch
and it can be found in the queue-4.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 241d2c54c62fa0939fc9a9512b48ac3434e90a89 Mon Sep 17 00:00:00 2001
From: Andrey Ryabinin <[email protected]>
Date: Thu, 2 Jul 2015 12:09:35 +0300
Subject: x86/kasan: Flush TLBs after switching CR3

From: Andrey Ryabinin <[email protected]>

commit 241d2c54c62fa0939fc9a9512b48ac3434e90a89 upstream.

load_cr3() doesn't cause tlb_flush if PGE enabled.

This may cause tons of false positive reports spamming the
kernel to death.

To fix this __flush_tlb_all() should be called explicitly
after CR3 changed.

Signed-off-by: Andrey Ryabinin <[email protected]>
Cc: Alexander Popov <[email protected]>
Cc: Alexander Potapenko <[email protected]>
Cc: Andrey Konovalov <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Dmitry Vyukov <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: 
http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 arch/x86/mm/kasan_init_64.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/arch/x86/mm/kasan_init_64.c
+++ b/arch/x86/mm/kasan_init_64.c
@@ -208,6 +208,7 @@ void __init kasan_init(void)
 
        memcpy(early_level4_pgt, init_level4_pgt, sizeof(early_level4_pgt));
        load_cr3(early_level4_pgt);
+       __flush_tlb_all();
 
        clear_pgds(KASAN_SHADOW_START, KASAN_SHADOW_END);
 
@@ -234,5 +235,6 @@ void __init kasan_init(void)
        memset(kasan_zero_page, 0, PAGE_SIZE);
 
        load_cr3(init_level4_pgt);
+       __flush_tlb_all();
        init_task.kasan_depth = 0;
 }


Patches currently in stable-queue which might be from [email protected] are

queue-4.1/x86-kasan-fix-kasan-shadow-region-page-tables.patch
queue-4.1/x86-kasan-fix-boot-crash-on-amd-processors.patch
queue-4.1/x86-init-clear-init_level4_pgt-earlier.patch
queue-4.1/x86-kasan-flush-tlbs-after-switching-cr3.patch
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