[tip:irq/core] x86: ioapic: Call free_irte only if interrupt remapping enabled

From: tip-bot for Yinghai Lu
Date: Tue Oct 19 2010 - 03:28:57 EST


Commit-ID: 9717967c4b704ce344c954afb5bb160aa9c01c34
Gitweb: http://git.kernel.org/tip/9717967c4b704ce344c954afb5bb160aa9c01c34
Author: Yinghai Lu <yinghai@xxxxxxxxxx>
AuthorDate: Mon, 18 Oct 2010 13:47:48 -0700
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Tue, 19 Oct 2010 09:25:33 +0200

x86: ioapic: Call free_irte only if interrupt remapping enabled

On a system that support intr-rempping when booting with "intremap=off"

[ 177.895501] BUG: unable to handle kernel NULL pointer dereference at 00000000000000f8
[ 177.913316] IP: [<ffffffff8145fc18>] free_irte+0x47/0xc0
...
[ 178.173326] Call Trace:
[ 178.173574] [<ffffffff810515b4>] destroy_irq+0x3a/0x75
[ 178.192934] [<ffffffff81051834>] arch_teardown_msi_irq+0xe/0x10
[ 178.193418] [<ffffffff81458dc3>] arch_teardown_msi_irqs+0x56/0x7f
[ 178.213021] [<ffffffff81458e79>] free_msi_irqs+0x8d/0xeb

Call free_irte only when interrupt remapping is enabled.

Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
LKML-Reference: <4CBCB274.7010108@xxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

---
arch/x86/kernel/apic/io_apic.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 20e47e0..8ae808d 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -3109,7 +3109,8 @@ void destroy_irq(unsigned int irq)

irq_set_status_flags(irq, IRQ_NOREQUEST|IRQ_NOPROBE);

- free_irte(irq);
+ if (intr_remapping_enabled)
+ free_irte(irq);
raw_spin_lock_irqsave(&vector_lock, flags);
__clear_irq_vector(irq, cfg);
raw_spin_unlock_irqrestore(&vector_lock, flags);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/