diff options
| author | Lai Jiangshan <laijs@cn.fujitsu.com> | 2014-05-16 11:50:42 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-06-11 12:03:24 -0700 |
| commit | 24d52daafcd53f109893ec2faf668c8eeef4a382 (patch) | |
| tree | 8587e0c33c954861f6bf01a9355469341181673c | |
| parent | 50faf9370b0aa357a9d114faafc2327505547928 (diff) | |
| download | lwn-24d52daafcd53f109893ec2faf668c8eeef4a382.tar.gz lwn-24d52daafcd53f109893ec2faf668c8eeef4a382.zip | |
sched: Fix hotplug vs. set_cpus_allowed_ptr()
commit 6acbfb96976fc3350e30d964acb1dbbdf876d55e upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | kernel/cpu.c | 6 | ||||
| -rw-r--r-- | kernel/sched/core.c | 1 |
2 files changed, 4 insertions, 3 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index 198a38883e64..bc255e25d5dd 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -698,10 +698,12 @@ 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 b4308d7da339..2672eca82a2b 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5270,7 +5270,6 @@ static int __cpuinit 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; |