On 05/22/2014 05:56 PM, tip-bot for Lai Jiangshan wrote: > 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]>
Reviewed-by: Srivatsa S. Bhat <[email protected]> Regards, Srivatsa S. Bhat > --- > 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; > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
