path: root/kernel/cpu.c
diff options
authorLai Jiangshan <laijs@cn.fujitsu.com>2014-05-16 11:50:42 +0800
committerIngo Molnar <mingo@kernel.org>2014-05-22 10:21:31 +0200
commit6acbfb96976fc3350e30d964acb1dbbdf876d55e (patch)
tree545a0c3d49d4603b568bf33c295f5c5504c0d334 /kernel/cpu.c
parent4dac0b638310d2e92f6e19958b73d4c97c9734bb (diff)
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 <laijs@cn.fujitsu.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael wang <wangyun@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Toshi Kani <toshi.kani@hp.com> Link: http://lkml.kernel.org/r/53758B12.8060609@cn.fujitsu.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/cpu.c')
1 files changed, 4 insertions, 2 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c
index a9e710eef0e2..247979a1b815 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)

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