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authorTakashi Iwai <tiwai@suse.de>2013-04-12 10:27:39 +0200
committerTakashi Iwai <tiwai@suse.de>2013-04-12 10:27:39 +0200
commit232a73dda2f2dba9002b727eb3ec76d82882b90c (patch)
tree308cdeea9bf18de71af79dcd5a30a8f2be9af6da /drivers/xen/events.c
parent889d66848b12d891248b03abcb2a42047f8e172a (diff)
parentca62bed0bbf9baf88d8bb404d72dee3b44ef057e (diff)
Merge tag 'asoc-v3.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Updates for v3.9 A few updates, more than I'd like, fixing some relatively small issues but mostly driver specific ones. Nothing wildly exciting so if it doesn't make v3.9 it won't be the end of the world but it'd be nice.
Diffstat (limited to 'drivers/xen/events.c')
-rw-r--r--drivers/xen/events.c20
1 files changed, 15 insertions, 5 deletions
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index d17aa41a9041..aa85881d17b2 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -403,11 +403,23 @@ static void unmask_evtchn(int port)
if (unlikely((cpu != cpu_from_evtchn(port))))
do_hypercall = 1;
- else
+ else {
+ /*
+ * Need to clear the mask before checking pending to
+ * avoid a race with an event becoming pending.
+ *
+ * EVTCHNOP_unmask will only trigger an upcall if the
+ * mask bit was set, so if a hypercall is needed
+ * remask the event.
+ */
+ sync_clear_bit(port, BM(&s->evtchn_mask[0]));
evtchn_pending = sync_test_bit(port, BM(&s->evtchn_pending[0]));
- if (unlikely(evtchn_pending && xen_hvm_domain()))
- do_hypercall = 1;
+ if (unlikely(evtchn_pending && xen_hvm_domain())) {
+ sync_set_bit(port, BM(&s->evtchn_mask[0]));
+ do_hypercall = 1;
+ }
+ }
/* Slow path (hypercall) if this is a non-local port or if this is
* an hvm domain and an event is pending (hvm domains don't have
@@ -418,8 +430,6 @@ static void unmask_evtchn(int port)
} else {
struct vcpu_info *vcpu_info = __this_cpu_read(xen_vcpu);
- sync_clear_bit(port, BM(&s->evtchn_mask[0]));
-
/*
* The following is basically the equivalent of
* 'hw_resend_irq'. Just like a real IO-APIC we 'lose