| From 541676078b52f365f53d46ee5517d305cd1b6350 Mon Sep 17 00:00:00 2001 |
| From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| Date: Fri, 15 Dec 2017 14:23:10 -0500 |
| Subject: membarrier: Disable preemption when calling smp_call_function_many() |
| |
| From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| |
| commit 541676078b52f365f53d46ee5517d305cd1b6350 upstream. |
| |
| smp_call_function_many() requires disabling preemption around the call. |
| |
| Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| Cc: Andrea Parri <parri.andrea@gmail.com> |
| Cc: Andrew Hunter <ahh@google.com> |
| Cc: Avi Kivity <avi@scylladb.com> |
| Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> |
| Cc: Boqun Feng <boqun.feng@gmail.com> |
| Cc: Dave Watson <davejwatson@fb.com> |
| Cc: H. Peter Anvin <hpa@zytor.com> |
| Cc: Linus Torvalds <torvalds@linux-foundation.org> |
| Cc: Maged Michael <maged.michael@gmail.com> |
| Cc: Michael Ellerman <mpe@ellerman.id.au> |
| Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com> |
| Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> |
| Cc: Paul Mackerras <paulus@samba.org> |
| Cc: Peter Zijlstra <peterz@infradead.org> |
| Cc: Thomas Gleixner <tglx@linutronix.de> |
| Link: http://lkml.kernel.org/r/20171215192310.25293-1-mathieu.desnoyers@efficios.com |
| Signed-off-by: Ingo Molnar <mingo@kernel.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| 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(); |