This is a note to let you know that I've just added the patch titled
xtensa: fix TLB sanity checker
to the 4.4-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:
xtensa-fix-tlb-sanity-checker.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 36de10c4788efc6efe6ff9aa10d38cb7eea4c818 Mon Sep 17 00:00:00 2001
From: Max Filippov <jcmvbkbc@xxxxxxxxx>
Date: Wed, 13 Nov 2019 13:18:31 -0800
Subject: xtensa: fix TLB sanity checker
From: Max Filippov <jcmvbkbc@xxxxxxxxx>
commit 36de10c4788efc6efe6ff9aa10d38cb7eea4c818 upstream.
Virtual and translated addresses retrieved by the xtensa TLB sanity
checker must be consistent, i.e. correspond to the same state of the
checked TLB entry. KASAN shadow memory is mapped dynamically using
auto-refill TLB entries and thus may change TLB state between the
virtual and translated address retrieval, resulting in false TLB
insanity report.
Move read_xtlb_translation close to read_xtlb_virtual to make sure that
read values are consistent.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: a99e07ee5e88 ("xtensa: check TLB sanity on return to userspace")
Signed-off-by: Max Filippov <jcmvbkbc@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/xtensa/mm/tlb.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/arch/xtensa/mm/tlb.c
+++ b/arch/xtensa/mm/tlb.c
@@ -218,6 +218,8 @@ static int check_tlb_entry(unsigned w, u
unsigned tlbidx = w | (e << PAGE_SHIFT);
unsigned r0 = dtlb ?
read_dtlb_virtual(tlbidx) : read_itlb_virtual(tlbidx);
+ unsigned r1 = dtlb ?
+ read_dtlb_translation(tlbidx) : read_itlb_translation(tlbidx);
unsigned vpn = (r0 & PAGE_MASK) | (e << PAGE_SHIFT);
unsigned pte = get_pte_for_vaddr(vpn);
unsigned mm_asid = (get_rasid_register() >> 8) & ASID_MASK;
@@ -233,8 +235,6 @@ static int check_tlb_entry(unsigned w, u
}
if (tlb_asid == mm_asid) {
- unsigned r1 = dtlb ? read_dtlb_translation(tlbidx) :
- read_itlb_translation(tlbidx);
if ((pte ^ r1) & PAGE_MASK) {
pr_err("%cTLB: way: %u, entry: %u, mapping: %08x->%08x, PTE: %08x\n",
dtlb ? 'D' : 'I', w, e, r0, r1, pte);
Patches currently in stable-queue which might be from jcmvbkbc@xxxxxxxxx are
queue-4.4/xtensa-fix-tlb-sanity-checker.patch
