aboutsummaryrefslogtreecommitdiff
path: root/drivers/char
diff options
context:
space:
mode:
authorHeinz Graalfs <graalfs@linux.vnet.ibm.com>2013-10-29 09:40:39 +1030
committerRusty Russell <rusty@rustcorp.com.au>2013-10-29 11:28:18 +1030
commit40e4dc530118dbb79e270d5554ac8415588378d2 (patch)
tree06582a56e89dc9cb3654de1bdcb9afa6adb5ce94 /drivers/char
parent7f03b17d5c3f3b63dcacf0e481cf94c9d07267ab (diff)
downloadlinux-linaro-stable-40e4dc530118dbb79e270d5554ac8415588378d2.tar.gz
virtio_console: verify if queue is broken after virtqueue_get_buf()
If virtqueue_get_buf() returns with a NULL pointer it should be verified if the virtqueue is broken, in order to avoid loop calling cpu_relax(). Signed-off-by: Heinz Graalfs <graalfs@linux.vnet.ibm.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Diffstat (limited to 'drivers/char')
-rw-r--r--drivers/char/virtio_console.c6
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 2a8d9a7a1834..feea87cc6b8f 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -577,7 +577,8 @@ static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id,
spin_lock(&portdev->c_ovq_lock);
if (virtqueue_add_outbuf(vq, sg, 1, &cpkt, GFP_ATOMIC) == 0) {
virtqueue_kick(vq);
- while (!virtqueue_get_buf(vq, &len))
+ while (!virtqueue_get_buf(vq, &len)
+ && !virtqueue_is_broken(vq))
cpu_relax();
}
spin_unlock(&portdev->c_ovq_lock);
@@ -650,7 +651,8 @@ static ssize_t __send_to_port(struct port *port, struct scatterlist *sg,
* we need to kmalloc a GFP_ATOMIC buffer each time the
* console driver writes something out.
*/
- while (!virtqueue_get_buf(out_vq, &len))
+ while (!virtqueue_get_buf(out_vq, &len)
+ && !virtqueue_is_broken(out_vq))
cpu_relax();
done:
spin_unlock_irqrestore(&port->outvq_lock, flags);