diff options
| author | Ian Campbell <ian.campbell@citrix.com> | 2010-07-29 11:16:35 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-08-13 13:27:34 -0700 |
| commit | fccf1002f4767104ed75422d9e34f21e4a29661f (patch) | |
| tree | 589e6ecd9d1b696347ffe3e10144afac96bc84f5 | |
| parent | ac013b45e6c2a32fbc11445a012bf88865750d1a (diff) | |
xen: Do not suspend IPI IRQs.
commit 4877c737283813bdb4bebfa3168c1585f6e3a8ca upstream.
In general the semantics of IPIs are that they are are expected to
continue functioning after dpm_suspend_noirq().
Specifically I have seen a deadlock between the callfunc IPI and the
stop machine used by xen's do_suspend() routine. If one CPU has already
called dpm_suspend_noirq() then there is a window where it can be sent
a callfunc IPI before all the other CPUs have entered stop_cpu().
If this happens then the first CPU ends up spinning in stop_cpu()
waiting for the other to rendezvous in state STOPMACHINE_PREPARE while
the other is spinning in csd_lock_wait().
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: xen-devel@lists.xensource.com
LKML-Reference: <1280398595-29708-4-git-send-email-ian.campbell@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | drivers/xen/events.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/xen/events.c b/drivers/xen/events.c index db8f506817f..28f133ae76a 100644 --- a/drivers/xen/events.c +++ b/drivers/xen/events.c @@ -536,6 +536,7 @@ int bind_ipi_to_irqhandler(enum ipi_vector ipi, if (irq < 0) return irq; + irqflags |= IRQF_NO_SUSPEND; retval = request_irq(irq, handler, irqflags, devname, dev_id); if (retval != 0) { unbind_from_irq(irq); |