diff options
| author | Bjørn Mork <bjorn@mork.no> | 2012-09-02 22:26:18 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-09-03 13:49:00 -0400 |
| commit | 85e87870fa18ec9f5df98e2d3b48f3699560a570 (patch) | |
| tree | 4130f26405eb5cd803b5f553faf8b4c8cb5a8548 /drivers/net/usb | |
| parent | 4c3a5bdae293f75cdf729c6c00124e8489af2276 (diff) | |
net: usbnet: fix softirq storm on suspend
Suspending an open usbnet device results in constant
rescheduling of usbnet_bh.
commit 65841fd5 "usbnet: handle remote wakeup asap"
refactored the usbnet_bh code to allow sharing the
urb allocate and submit code with usbnet_resume. In
this process, a test for, and immediate return on,
ENOLINK from rx_submit was unintentionally dropped.
The rx queue will not grow if rx_submit fails,
making usbnet_bh reschedule itself. This results
in a softirq storm if the error is persistent.
rx_submit translates the usb_submit_urb error
EHOSTUNREACH into ENOLINK, so this is an expected
and persistent error for a suspended device. The
old code tested for this condition and avoided
rescheduling. Putting this test back.
Cc: <stable@vger.kernel.org> # v3.5
Cc: Ming Lei <ming.lei@canonical.com>
Cc: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/usb')
| -rw-r--r-- | drivers/net/usb/usbnet.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c index fd4b26d46fd5..fc9f578a1e25 100644 --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -1201,19 +1201,26 @@ deferred: } EXPORT_SYMBOL_GPL(usbnet_start_xmit); -static void rx_alloc_submit(struct usbnet *dev, gfp_t flags) +static int rx_alloc_submit(struct usbnet *dev, gfp_t flags) { struct urb *urb; int i; + int ret = 0; /* don't refill the queue all at once */ for (i = 0; i < 10 && dev->rxq.qlen < RX_QLEN(dev); i++) { urb = usb_alloc_urb(0, flags); if (urb != NULL) { - if (rx_submit(dev, urb, flags) == -ENOLINK) - return; + ret = rx_submit(dev, urb, flags); + if (ret) + goto err; + } else { + ret = -ENOMEM; + goto err; } } +err: + return ret; } /*-------------------------------------------------------------------------*/ @@ -1257,7 +1264,8 @@ static void usbnet_bh (unsigned long param) int temp = dev->rxq.qlen; if (temp < RX_QLEN(dev)) { - rx_alloc_submit(dev, GFP_ATOMIC); + if (rx_alloc_submit(dev, GFP_ATOMIC) == -ENOLINK) + return; if (temp != dev->rxq.qlen) netif_dbg(dev, link, dev->net, "rxqlen %d --> %d\n", |