Fix panic in panic in smp_irq_move_cleanup_interrupt

This commit is contained in:
Justin M. Forbes 2012-11-15 11:00:40 -06:00
parent de28018acf
commit c428a20204
2 changed files with 58 additions and 1 deletions

View File

@ -62,7 +62,7 @@ Summary: The Linux kernel
# For non-released -rc kernels, this will be appended after the rcX and
# gitX tags, so a 3 here would become part of release "0.rcX.gitX.3"
#
%global baserelease 7
%global baserelease 8
%global fedora_build %{baserelease}
# base_sublevel is the kernel version we're starting with and patching
@ -796,6 +796,8 @@ Patch22110: usb-audio-fix-crash-at-re-preparing-the-PCM-stream.patch
Patch22111: USB-EHCI-urb-hcpriv-should-not-be-NULL.patch
Patch22112: USB-report-submission-of-active-URBs.patch
Patch22113: smp_irq_move_cleanup_interrupt.patch
# END OF PATCH DEFINITIONS
%endif
@ -1539,6 +1541,8 @@ ApplyPatch usb-audio-fix-crash-at-re-preparing-the-PCM-stream.patch
ApplyPatch USB-EHCI-urb-hcpriv-should-not-be-NULL.patch
ApplyPatch USB-report-submission-of-active-URBs.patch
ApplyPatch smp_irq_move_cleanup_interrupt.patch
# END OF PATCH APPLICATIONS
%endif
@ -2404,6 +2408,9 @@ fi
# ||----w |
# || ||
%changelog
* Thu Nov 15 2012 Justin M. Forbes <jforbes@redhat.com>
- Fix panic in panic in smp_irq_move_cleanup_interrupt
* Wed Nov 14 2012 Josh Boyer <jwboyer@redhat.com>
- Fix module signing of kernel flavours

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@ -0,0 +1,50 @@
commit 94777fc51b3ad85ff9f705ddf7cdd0eb3bbad5a6
Author: Dimitri Sivanich <sivanich@sgi.com>
Date: Tue Oct 16 07:50:21 2012 -0500
x86/irq/ioapic: Check for valid irq_cfg pointer in smp_irq_move_cleanup_interrupt
Posting this patch to fix an issue concerning sparse irq's that
I raised a while back. There was discussion about adding
refcounting to sparse irqs (to fix other potential race
conditions), but that does not appear to have been addressed
yet. This covers the only issue of this type that I've
encountered in this area.
A NULL pointer dereference can occur in
smp_irq_move_cleanup_interrupt() if we haven't yet setup the
irq_cfg pointer in the irq_desc.irq_data.chip_data.
In create_irq_nr() there is a window where we have set
vector_irq in __assign_irq_vector(), but not yet called
irq_set_chip_data() to set the irq_cfg pointer.
Should an IRQ_MOVE_CLEANUP_VECTOR hit the cpu in question during
this time, smp_irq_move_cleanup_interrupt() will attempt to
process the aforementioned irq, but panic when accessing
irq_cfg.
Only continue processing the irq if irq_cfg is non-NULL.
Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Joerg Roedel <joerg.roedel@amd.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Alexander Gordeev <agordeev@redhat.com>
Link: http://lkml.kernel.org/r/20121016125021.GA22935@sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index c265593..1817fa9 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2257,6 +2257,9 @@ asmlinkage void smp_irq_move_cleanup_interrupt(void)
continue;
cfg = irq_cfg(irq);
+ if (!cfg)
+ continue;
+
raw_spin_lock(&desc->lock);
/*