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| author | David Vrabel <david.vrabel@citrix.com> | 2015-05-19 18:40:49 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-06-06 08:19:32 -0700 |
| commit | 8d3cbb90968e6fc0114b6666d393ad968eaeb16a (patch) | |
| tree | 2f5bc82a84ff562e670da1b0b9f5c0da6b3b7aed /include | |
| parent | c018f62178c6a14d61c6dc3885d42e0c3f977782 (diff) | |
| download | lwn-8d3cbb90968e6fc0114b6666d393ad968eaeb16a.tar.gz lwn-8d3cbb90968e6fc0114b6666d393ad968eaeb16a.zip | |
xen/events: don't bind non-percpu VIRQs with percpu chip
commit 77bb3dfdc0d554befad58fdefbc41be5bc3ed38a upstream.
A non-percpu VIRQ (e.g., VIRQ_CONSOLE) may be freed on a different
VCPU than it is bound to. This can result in a race between
handle_percpu_irq() and removing the action in __free_irq() because
handle_percpu_irq() does not take desc->lock. The interrupt handler
sees a NULL action and oopses.
Only use the percpu chip/handler for per-CPU VIRQs (like VIRQ_TIMER).
# cat /proc/interrupts | grep virq
40: 87246 0 xen-percpu-virq timer0
44: 0 0 xen-percpu-virq debug0
47: 0 20995 xen-percpu-virq timer1
51: 0 0 xen-percpu-virq debug1
69: 0 0 xen-dyn-virq xen-pcpu
74: 0 0 xen-dyn-virq mce
75: 29 0 xen-dyn-virq hvc_console
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/xen/events.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/xen/events.h b/include/xen/events.h index c9c85cf84895..5d84cd0a51b7 100644 --- a/include/xen/events.h +++ b/include/xen/events.h @@ -14,7 +14,7 @@ int bind_evtchn_to_irqhandler(unsigned int evtchn, irq_handler_t handler, unsigned long irqflags, const char *devname, void *dev_id); -int bind_virq_to_irq(unsigned int virq, unsigned int cpu); +int bind_virq_to_irq(unsigned int virq, unsigned int cpu, bool percpu); int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu, irq_handler_t handler, unsigned long irqflags, const char *devname, |