summaryrefslogtreecommitdiffstats
path: root/arch/xtensa/kernel
diff options
context:
space:
mode:
authorMax Filippov <jcmvbkbc@gmail.com>2022-04-23 12:52:23 +0200
committerMax Filippov <jcmvbkbc@gmail.com>2022-05-02 04:58:12 +0200
commit2a26f4ee399db65ccd97465d57002339afe48572 (patch)
treebb376e8e804d44c7768f9f68fa2f8ed94f7d8325 /arch/xtensa/kernel
parentxtensa: fix declaration of _SecondaryResetVector_text_* (diff)
downloadlinux-2a26f4ee399db65ccd97465d57002339afe48572.tar.xz
linux-2a26f4ee399db65ccd97465d57002339afe48572.zip
xtensa: don't leave invalid TLB entry in fast_store_prohibited
When fast_store_prohibited needs to go to the C-level exception handler it leaves TLB entry that caused page fault in the TLB. If the faulting task gets switched to a different CPU and completes page table update there the TLB entry will get out of sync with the page table which may cause a livelock on access to that page. Invalidate faulting TLB entry on a slow path exit from the fast_store_prohibited. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Diffstat (limited to 'arch/xtensa/kernel')
-rw-r--r--arch/xtensa/kernel/entry.S6
1 files changed, 5 insertions, 1 deletions
diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S
index d703ed31254a..7852481d779c 100644
--- a/arch/xtensa/kernel/entry.S
+++ b/arch/xtensa/kernel/entry.S
@@ -1882,7 +1882,11 @@ ENTRY(fast_store_prohibited)
j 8b
2: /* If there was a problem, handle fault in C */
-
+ rsr a1, excvaddr
+ pdtlb a0, a1
+ bbci.l a0, DTLB_HIT_BIT, 1f
+ idtlb a0
+1:
rsr a3, depc # still holds a2
s32i a3, a2, PT_AREG2
mov a1, a2