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 <graa...@linux.vnet.ibm.com>
---
drivers/char/virtio_console.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 1b456fe..9dce2f0 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -574,7 +574,8 @@ 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);
@@ -647,7 +648,8 @@ 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);
--
1.8.3.1
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