On 01/27/2014 06:22 PM, Ben Hutchings wrote: > On Mon, 2014-01-27 at 17:40 +0800, Jason Wang wrote: >> On 01/27/2014 04:35 PM, David Miller wrote: >>> From: Jason Wang <jasowang@xxxxxxxxxx> >>> Date: Mon, 27 Jan 2014 15:30:54 +0800 >>> >>>> Call netif_carrier_on() after register_device(). Otherwise it won't work since >>>> the device was still in NETREG_UNINITIALIZED state. >>>> >>>> Fixes a68f9614614749727286f675d15f1e09d13cb54a >>>> (hyperv: Fix race between probe and open calls) >>>> >>>> Cc: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx> >>>> Cc: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> >>>> Reported-by: Di Nie <dnie@xxxxxxxxxx> >>>> Tested-by: Di Nie <dnie@xxxxxxxxxx> >>>> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx> >>> A device up can occur at the moment you call register_netdevice(), >>> therefore that up call can see the carrier as down and fail or >>> similar. So you really cannot resolve the carrier to be on in this >>> way. >> True, we need a workqueue to synchronize them. > Whatever for? All you need to do is: > > rtnl_lock(); > register_netdevice(); > netif_carrier_on(); > rtnl_unlock(); > > It would be nice if we could make the current code work with a change in > the core, though. > > Ben. > Looks like the link status interrupt may happen during this (after netvsc_device_add() was called by rndis_filter_device_add()) without any synchronization. This may lead a wrong link status here. _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
