Re: [PATCH 40/45] powerpc, irq: Use GFP_ATOMIC allocations in atomic context
From: Michael Ellerman <hidden>
Date: 2013-06-25 02:08:47
Also in:
linux-arch, linux-pm, lkml, netdev
On Sun, Jun 23, 2013 at 07:17:00PM +0530, Srivatsa S. Bhat wrote:
The function migrate_irqs() is called with interrupts disabled and hence its not safe to do GFP_KERNEL allocations inside it, because they can sleep. So change the gfp mask to GFP_ATOMIC.
OK so it gets there via:
__stop_machine()
take_cpu_down()
__cpu_disable()
smp_ops->cpu_disable()
generic_cpu_disable()
migrate_irqs()
quoted hunk ↗ jump to hunk
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index ea185e0..ca39bac 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c@@ -412,7 +412,7 @@ void migrate_irqs(void) cpumask_var_t mask; const struct cpumask *map = cpu_online_mask; - alloc_cpumask_var(&mask, GFP_KERNEL); + alloc_cpumask_var(&mask, GFP_ATOMIC);
We're not checking for allocation failure, which we should be. But this code is only used on powermac and 85xx, so it should probably just be a TODO to fix this up to handle the failure. cheers