From: Lai Jiangshan <la...@cn.fujitsu.com> 3.12-stable review patch. If anyone has any objections, please let me know.
=============== 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 <la...@cn.fujitsu.com> Signed-off-by: Peter Zijlstra <pet...@infradead.org> Cc: Andrew Morton <a...@linux-foundation.org> Cc: Gautham R. Shenoy <e...@linux.vnet.ibm.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Michael wang <wang...@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortma...@windriver.com> Cc: Rafael J. Wysocki <rafael.j.wyso...@intel.com> Cc: Srivatsa S. Bhat <srivatsa.b...@linux.vnet.ibm.com> Cc: Toshi Kani <toshi.k...@hp.com> Link: http://lkml.kernel.org/r/53758b12.8060...@cn.fujitsu.com Signed-off-by: Ingo Molnar <mi...@kernel.org> Signed-off-by: Jiri Slaby <jsl...@suse.cz> --- 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 d7f07a2da5a6..92599d897125 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -695,10 +695,12 @@ 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 a494ace683e3..07039cba59d9 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -4726,7 +4726,6 @@ 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; -- 2.0.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/