This is a note to let you know that I've just added the patch titled
membarrier: Disable preemption when calling smp_call_function_many()
to the 4.14-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:
membarrier-disable-preemption-when-calling-smp_call_function_many.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 541676078b52f365f53d46ee5517d305cd1b6350 Mon Sep 17 00:00:00 2001
From: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Date: Fri, 15 Dec 2017 14:23:10 -0500
Subject: membarrier: Disable preemption when calling smp_call_function_many()
From: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
commit 541676078b52f365f53d46ee5517d305cd1b6350 upstream.
smp_call_function_many() requires disabling preemption around the call.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Cc: Andrea Parri <parri.andrea@xxxxxxxxx>
Cc: Andrew Hunter <ahh@xxxxxxxxxx>
Cc: Avi Kivity <avi@xxxxxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Boqun Feng <boqun.feng@xxxxxxxxx>
Cc: Dave Watson <davejwatson@xxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Maged Michael <maged.michael@xxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Paul E . McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
Cc: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/20171215192310.25293-1-mathieu.desnoyers@xxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/sched/membarrier.c | 2 ++
1 file changed, 2 insertions(+)
--- a/kernel/sched/membarrier.c
+++ b/kernel/sched/membarrier.c
@@ -89,7 +89,9 @@ static int membarrier_private_expedited(
rcu_read_unlock();
}
if (!fallback) {
+ preempt_disable();
smp_call_function_many(tmpmask, ipi_mb, NULL, 1);
+ preempt_enable();
free_cpumask_var(tmpmask);
}
cpus_read_unlock();
Patches currently in stable-queue which might be from mathieu.desnoyers@xxxxxxxxxxxx are
queue-4.14/membarrier-disable-preemption-when-calling-smp_call_function_many.patch
queue-4.14/kvm-fix-stack-out-of-bounds-read-in-write_mmio.patch