x86: Fix NULL pointer access in irq_force_complete_move() for Xen guests
authorPrarit Bhargava <prarit@redhat.com>
Tue, 27 Apr 2010 15:24:42 +0000 (11:24 -0400)
committerH. Peter Anvin <hpa@zytor.com>
Fri, 30 Apr 2010 21:31:38 +0000 (14:31 -0700)
Upstream PV guests fail to boot because of a NULL pointer in
irq_force_complete_move().  It is possible that xen guests have
irq_desc->chip_data = NULL.

Test for NULL chip_data pointer before attempting to complete an irq move.

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
LKML-Reference: <20100427152434.16193.49104.sendpatchset@prarit.bos.redhat.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: <stable@kernel.org> [2.6.33]
arch/x86/kernel/apic/io_apic.c

index 127b8718abfb0abd389334865f0bf3159b8e0fa3..eb2789c3f7216a43eb4017e44fed32556a703918 100644 (file)
@@ -2545,6 +2545,9 @@ void irq_force_complete_move(int irq)
        struct irq_desc *desc = irq_to_desc(irq);
        struct irq_cfg *cfg = desc->chip_data;
 
+       if (!cfg)
+               return;
+
        __irq_complete_move(&desc, cfg->vector);
 }
 #else