❦ 4 avril 2018 15:59 +0200, Michal Privoznik <mprivozn@xxxxxxxxxx> : >> I may have missed this suggestion. Maybe Dan only sent it to you? > > No, there is another thread where this issue is discussed: > > https://www.redhat.com/archives/libvir-list/2018-April/msg00190.html > > In the >> meantime, could I change the locks around virHashForEach() and similar >> as read/write locks? >> > > You can do that locally, but as a patch it's very unlikely to be > accepted upstream because we've introduced RW locks to be able to access > domain list from multiple threads. Looking a bit more, the whole "iterating" bit is currently unsafe. First, it is racy since it's "check then take". Two threads may check the value is false and start iterating both. Moreover, at some places, it is not set, for example in virHashAddOrUpdateEntry(). So, it would be possible to call this function and during the update to iterate over the hash. This seems to be prevented only by callers using RW lock. So, it seems we can just remove this "iterating" bool and just check all users of these functions are using the appropriate lock. -- Make sure all variables are initialised before use. - The Elements of Programming Style (Kernighan & Plauger) _______________________________________________ libvirt-users mailing list libvirt-users@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvirt-users
