kernel.git/drivers/net/xen-netback, branch linux-5.8.y

net: xen-netback: hash.c: Use built-in RCU list checking

2020-01-17T09:57:22Z

list_for_each_entry_rcu has built-in RCU and lock checking. Pass cond argument to list_for_each_entry_rcu. Signed-off-by: Madhuparna Bhowmik Acked-by: Wei Liu Signed-off-by: David S. Miller

xen-netback: support dynamic unbind/bind

2019-12-26T23:16:26Z

By re-attaching RX, TX, and CTL rings during connect() rather than assuming they are freshly allocated (i.e. assuming the counters are zero), and avoiding forcing state to Closed in netback_remove() it is possible for vif instances to be unbound and re-bound from and to (respectively) a running guest. Dynamic unbind/bind is a highly useful feature for a backend module as it allows it to be unloaded and re-loaded (i.e. updated) without requiring domUs to be halted. This has been tested by running iperf as a server in the test VM and then running a client against it in a continuous loop, whilst also running: while true; do echo vif-$DOMID-$VIF >unbind; echo down; rmmod xen-netback; echo unloaded; modprobe xen-netback; cd $(pwd); brctl addif xenbr0 vif$DOMID.$VIF; ip link set vif$DOMID.$VIF up; echo up; sleep 5; done in dom0 from /sys/bus/xen-backend/drivers/vif to continuously unbind, unload, re-load, re-bind and re-plumb the backend. Clearly a performance drop was seen but no TCP connection resets were observed during this test and moreover a parallel SSH connection into the guest remained perfectly usable throughout. Signed-off-by: Paul Durrant Reviewed-by: Wei Liu Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2019-12-22T23:15:05Z

Mere overlapping changes in the conflicts here. Signed-off-by: David S. Miller

xen-netback: remove 'hotplug-status' once it has served its purpose

2019-12-18T07:03:33Z

Removing the 'hotplug-status' node in netback_remove() is wrong; the script may not have completed. Only remove the node once the watch has fired and has been unregistered. Signed-off-by: Paul Durrant Acked-by: Wei Liu Signed-off-by: David S. Miller

xen-netback: switch state to InitWait at the end of netback_probe()...

2019-12-18T07:03:33Z

...as the comment above the function states. The switch to Initialising at the start of the function is somewhat bogus as the toolstack will have set that initial state anyway. To behave correctly, a backend should switch to InitWait once it has set up all xenstore values that may be required by a initialising frontend. This patch calls backend_switch_state() to make the transition at the appropriate point. NOTE: backend_switch_state() ignores errors from xenbus_switch_state() and so this patch removes an error path from netback_probe(). This means a failure to change state at this stage (in the absence of other failures) will leave the device instantiated. This is highly unlikley to happen as a failure to change state would indicate a failure to write to xenstore, and that will trigger other error paths. Also, a 'stuck' device can still be cleaned up using 'unbind' in any case. Signed-off-by: Paul Durrant Acked-by: Wei Liu Signed-off-by: David S. Miller

xen-netback: move netback_probe() and netback_remove() to the end...

2019-12-18T07:03:33Z

...of xenbus.c This is a cosmetic function re-ordering to reduce churn in a subsequent patch. Some style fix-up was done to make checkpatch.pl happier. No functional change. Signed-off-by: Paul Durrant Acked-by: Wei Liu Signed-off-by: David S. Miller

xen-netback: avoid race that can lead to NULL pointer dereference

2019-12-15T19:40:15Z

In function xenvif_disconnect_queue(), the value of queue->rx_irq is zeroed *before* queue->task is stopped. Unfortunately that task may call notify_remote_via_irq(queue->rx_irq) and calling that function with a zero value results in a NULL pointer dereference in evtchn_from_irq(). This patch simply re-orders things, stopping all tasks before zero-ing the irq values, thereby avoiding the possibility of the race. Fixes: 2ac061ce97f4 ("xen/netback: cleanup init and deinit code") Signed-off-by: Paul Durrant Acked-by: Wei Liu Signed-off-by: Jakub Kicinski

xen/netback: cleanup init and deinit code

2019-10-22T16:52:04Z

Do some cleanup of the netback init and deinit code: - add an omnipotent queue deinit function usable from xenvif_disconnect_data() and the error path of xenvif_connect_data() - only install the irq handlers after initializing all relevant items (especially the kthreads related to the queue) - there is no need to use get_task_struct() after creating a kthread and using put_task_struct() again after having stopped it. - use kthread_run() instead of kthread_create() to spare the call of wake_up_process(). Signed-off-by: Juergen Gross Reviewed-by: Paul Durrant Signed-off-by: Jakub Kicinski

xen/netback: fix error path of xenvif_connect_data()

2019-10-19T18:43:29Z

xenvif_connect_data() calls module_put() in case of error. This is wrong as there is no related module_get(). Remove the superfluous module_put(). Fixes: 279f438e36c0a7 ("xen-netback: Don't destroy the netdev until the vif is shut down") Cc: # 3.12 Signed-off-by: Juergen Gross Reviewed-by: Paul Durrant Reviewed-by: Wei Liu Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2019-08-19T18:54:03Z

Merge conflict of mlx5 resolved using instructions in merge commit 9566e650bf7fdf58384bb06df634f7531ca3a97e. Signed-off-by: David S. Miller