diff mbox series

[2/4] virtio_net: add a timeout in virtnet_send_command()

Message ID 20230122100526.2302556-3-lvivier@redhat.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series virtio_net: vdpa: update MAC address when it is generated by virtio-net | expand

Checks

Context Check Description
netdev/tree_selection success Guessed tree name to be net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers warning 3 maintainers not CCed: edumazet@google.com pabeni@redhat.com kuba@kernel.org
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 18 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Laurent Vivier Jan. 22, 2023, 10:05 a.m. UTC 
if the device control queue is buggy, don't crash the kernel by
waiting for ever the response.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
 drivers/net/virtio_net.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 25511a86590e..29b3cc72082d 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -1974,6 +1974,7 @@  static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
 	struct scatterlist *sgs[4], hdr, stat;
 	unsigned out_num = 0, tmp;
 	int ret;
+	unsigned long timeout;
 
 	/* Caller should know better */
 	BUG_ON(!virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ));
@@ -2006,8 +2007,10 @@  static bool virtnet_send_command(struct virtnet_info *vi, u8 class, u8 cmd,
 	/* Spin for a response, the kick causes an ioport write, trapping
 	 * into the hypervisor, so the request should be handled immediately.
 	 */
+	timeout = jiffies + 20 * HZ;
 	while (!virtqueue_get_buf(vi->cvq, &tmp) &&
-	       !virtqueue_is_broken(vi->cvq))
+	       !virtqueue_is_broken(vi->cvq) &&
+	       !time_after(jiffies, timeout))
 		cpu_relax();
 
 	return vi->ctrl->status == VIRTIO_NET_OK;