* Sebastian Andrzej Siewior | 2016-05-12 10:42:30 [+0200]: >>diff --git a/mm/swap.c b/mm/swap.c >>index ca194ae..84c3c21 100644 >>--- a/mm/swap.c >>+++ b/mm/swap.c >>@@ -821,9 +821,9 @@ void lru_add_drain_cpu(int cpu) >> unsigned long flags; >> >> /* No harm done if a racing interrupt already did this */ >>- local_lock_irqsave(rotate_lock, flags); >>+ local_lock_irqsave_other_cpu(rotate_lock, flags, cpu); >> pagevec_move_tail(pvec); >>- local_unlock_irqrestore(rotate_lock, flags); >>+ local_unlock_irqrestore_other_cpu(rotate_lock, flags, cpu); > >This piece might be required independently of this patch. It would be >nice to have it in page_alloc_cpu_notify() :) I take care of this… no, I won't :) It looks halfway like an upstream bug. Vanila has here local_irq_save() which always matches the local CPU except when it is invoked from page_alloc_cpu_notify() CPU_DEAD notifier. Here it does not matter because the CPU is gone and won't take the locks anymore. Unless, we start taking them cross-CPU which is only possible with this patch. Sebastian -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
