[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: [libvirt] [PATCH] nwfilter: re-order lock grabbed by IP addr. learn thread



On 11/18/2010 05:16 AM, Stefan Berger wrote:
> The IP address learning thread was causing a deadlock when it
> instantiated a filter while a filter update/change was ongoing. The
> reason for this was the ordering of locks due to the following calls
> 
> virNWFilterUnlockFilterUpdates()
> virNWFilterPoolObjFindByName()
> 

> 
> + * Call this function while holding the NWFilter filter update lock
>  static int
>  __virNWFilterInstantiateFilter(virConnectPtr conn,

I'm assuming that's a bogus line in your patch,

>                                 bool teardownOld,
> @@ -823,23 +822,30 @@ _virNWFilterInstantiateFilter(virConnect
>                            ? net->data.direct.linkdev
>                            : NULL;
>      int ifindex;
> +    int rc;
> 
>      if (ifaceGetIndex(true, net->ifname, &ifindex))
>          return 1;
...
> +    virNWFilterLockFilterUpdates();
> +
> +    rc = __virNWFilterInstantiateFilter(conn,

...especially given the fact that you grab the lock here, so
__virNWFilterInstantiateFilter should NOT have the filter update lock in
the caller.

ACK, once you fix that compilation error due to the stray line.

-- 
Eric Blake   eblake redhat com    +1-801-349-2682
Libvirt virtualization library http://libvirt.org

Attachment: signature.asc
Description: OpenPGP digital signature


[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]