> -----Original Message----- > From: Vitaly Kuznetsov [mailto:vkuznets@xxxxxxxxxx] > Sent: Tuesday, July 14, 2015 9:03 AM > To: Dexuan Cui > Cc: devel@xxxxxxxxxxxxxxxxxxxxxx; KY Srinivasan; Haiyang Zhang; linux- > kernel@xxxxxxxxxxxxxxx > Subject: Re: [PATCH] Drivers: hv: vmbus: prevent new subchannel creation > on device shutdown > > Dexuan Cui <decui@xxxxxxxxxxxxx> writes: > > >> -----Original Message----- > >> From: Vitaly Kuznetsov > >> Sent: Monday, July 13, 2015 20:19 > >> Subject: [PATCH] Drivers: hv: vmbus: prevent new subchannel creation on > device > >> shutdown > >> > >> When a new subchannel offer from host comes during device shutdown > (e.g. > >> when a netvsc/storvsc module is unloadedshortly after it was loaded) a > >> crash can happen as vmbus_process_offer() is not anyhow serialized with > >> vmbus_remove(). > > > > How about vmbus_onoffer_rescind()? > > It's not serialized with vmbus_remove() either, so I think there is an issue > too? > > > > I remember when 'rmmod hv_netvsc', we get a rescind-offer message for > > each subchannel. > > > > True, I think we have a race with rescind messages as well, we just > never saw crashes for some reason. I'll think how we can make the fix > more general. In an earlier email I had outlined how I was planning to address original issue. I have a patch based on the logic I had described - essentially put the burden on the probe call to ensure that the open (including sub-channels) is complete before we return from probe. I will post this shortly. Regards, K. Y _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
