diff options
author | Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> | 2010-05-28 15:28:27 -0700 |
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committer | Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> | 2010-05-28 15:28:27 -0700 |
commit | 3f5e554f669098c84c82ce75e7577f7e0f3fccde (patch) | |
tree | fb8147269b5f9b412e03e3539fdb2dd3cedc0ace /drivers/xen | |
parent | 1a1a17cddbfb1f81222b3f18ee8530c41fbc3b82 (diff) |
xen/evtchn: don't do unbind_from_irqhandler under spinlock
unbind_from_irqhandler can end up doing /proc operations, which can't
happen under a spinlock. So before removing the IRQ handler,
disable the irq under the port_user lock (masking the underlying event
channel and making sure the irq handler isn't running concurrently and
won't start running), then remove the handler without the lock.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Diffstat (limited to 'drivers/xen')
-rw-r--r-- | drivers/xen/evtchn.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/drivers/xen/evtchn.c b/drivers/xen/evtchn.c index f79ac5ca379..6a3a12945d0 100644 --- a/drivers/xen/evtchn.c +++ b/drivers/xen/evtchn.c @@ -375,10 +375,12 @@ static long evtchn_ioctl(struct file *file, break; } - evtchn_unbind_from_user(u, unbind.port); + disable_irq(irq_from_evtchn(unbind.port)); spin_unlock_irq(&port_user_lock); + evtchn_unbind_from_user(u, unbind.port); + rc = 0; break; } @@ -484,11 +486,18 @@ static int evtchn_release(struct inode *inode, struct file *filp) if (get_port_user(i) != u) continue; - evtchn_unbind_from_user(get_port_user(i), i); + disable_irq(irq_from_evtchn(i)); } spin_unlock_irq(&port_user_lock); + for (i = 0; i < NR_EVENT_CHANNELS; i++) { + if (get_port_user(i) != u) + continue; + + evtchn_unbind_from_user(get_port_user(i), i); + } + kfree(u->name); kfree(u); |