Commit-ID: 6acbfb96976fc3350e30d964acb1dbbdf876d55e
Gitweb: http://git.kernel.org/tip/6acbfb96976fc3350e30d964acb1dbbdf876d55e
Author: Lai Jiangshan <[email protected]>
AuthorDate: Fri, 16 May 2014 11:50:42 +0800
Committer: Ingo Molnar <[email protected]>
CommitDate: Thu, 22 May 2014 10:21:31 +0200
sched: Fix hotplug vs. set_cpus_allowed_ptr()
Lai found that:
WARNING: CPU: 1 PID: 13 at arch/x86/kernel/smp.c:124
native_smp_send_reschedule+0x2d/0x4b()
...
migration_cpu_stop+0x1d/0x22
was caused by set_cpus_allowed_ptr() assuming that cpu_active_mask is
always a sub-set of cpu_online_mask.
This isn't true since 5fbd036b552f ("sched: Cleanup cpu_active madness").
So set active and online at the same time to avoid this particular
problem.
Fixes: 5fbd036b552f ("sched: Cleanup cpu_active madness")
Signed-off-by: Lai Jiangshan <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Gautham R. Shenoy <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Michael wang <[email protected]>
Cc: Paul Gortmaker <[email protected]>
Cc: Rafael J. Wysocki <[email protected]>
Cc: Srivatsa S. Bhat <[email protected]>
Cc: Toshi Kani <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
kernel/cpu.c | 6 ++++--
kernel/sched/core.c | 1 -
2 files changed, 4 insertions(+), 3 deletions(-)
diff --git a/kernel/cpu.c b/kernel/cpu.c
index a9e710e..247979a 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -726,10 +726,12 @@ void set_cpu_present(unsigned int cpu, bool present)
void set_cpu_online(unsigned int cpu, bool online)
{
- if (online)
+ if (online) {
cpumask_set_cpu(cpu, to_cpumask(cpu_online_bits));
- else
+ cpumask_set_cpu(cpu, to_cpumask(cpu_active_bits));
+ } else {
cpumask_clear_cpu(cpu, to_cpumask(cpu_online_bits));
+ }
}
void set_cpu_active(unsigned int cpu, bool active)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 44e00ab..86f3890 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -5076,7 +5076,6 @@ static int sched_cpu_active(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_STARTING:
case CPU_DOWN_FAILED:
set_cpu_active((long)hcpu, true);
return NOTIFY_OK;
--
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