From 7b79462a20826a7269322113c68ca78d5f67c0bd Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Sat, 30 Oct 2010 01:19:29 -0700 Subject: [PATCH] x86: Check irq_remapped instead of remapping_enabled in destroy_irq() Russ Anderson reported: | There is a regression that is causing a NULL pointer dereference | in free_irte when shutting down xpc. git bisect narrowed it down | to git commit d585d06(intr_remap: Simplify the code further), which | changed free_irte(). Reverse applying the patch fixes the problem. We need to use irq_remapped() for each irq instead of checking only intr_remapping_enabled as there might be non remapped irqs even when remapping is enabled. [ tglx: use cfg instead of retrieving it again. Massaged changelog ] Reported-bisected-and-tested-by: Russ Anderson Signed-off-by: Yinghai Lu Cc: Suresh Siddha LKML-Reference: <4CCBD511.40607@kernel.org> Signed-off-by: Thomas Gleixner --- arch/x86/kernel/apic/io_apic.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index 0929191d83cf..7cc0a721f628 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -3109,7 +3109,7 @@ void destroy_irq(unsigned int irq) irq_set_status_flags(irq, IRQ_NOREQUEST|IRQ_NOPROBE); - if (intr_remapping_enabled) + if (irq_remapped(cfg)) free_irte(irq); raw_spin_lock_irqsave(&vector_lock, flags); __clear_irq_vector(irq, cfg); -- 2.20.1