Since we introduced fine grained locking into the QEMU driver so that VM start can run in parallel, we appear to have caused a race with the nwfilter code. In particular since we no longer hold the global QEMU driver lock for the duration of VM startup we have a lock ordering flaw. This results in deadlock when nwfilter operations happen in parallel with VM startup. This also affects the LXC driver. This patch series attempts to address the problem https://bugzilla.redhat.com/show_bug.cgi?id=929412 the removal of the windows thread impl isn't strictly required, I just didn't want to waste time creating a read/write lock impl for Windows threads. See also this callgraph http://berrange.fedorapeople.org/nwfilter.ps In v3: - Removed addition of extra lock for serializing iptables since it was overkill - Added patch to make libvirt compile with mingw32-pthreads from Fedora 19 and earlier - Fix errno handling with rwlock creation In v2: - Re-ordered patches and squashed two together - Add missing locking in state reload function - Don't remove locking from virNWFilterInstantiateFilterLate *** BLURB HERE *** Daniel P. Berrange (4): Add a read/write lock implementation Fix pthread_sigmask check for mingw32 without winpthreads Remove windows thread implementation in favour of pthreads Push nwfilter update locking up to top level configure.ac | 21 +- src/Makefile.am | 4 - src/conf/nwfilter_conf.c | 23 +- src/conf/nwfilter_conf.h | 3 +- src/libvirt_private.syms | 8 +- src/lxc/lxc_driver.c | 6 + src/nwfilter/nwfilter_driver.c | 10 +- src/nwfilter/nwfilter_gentech_driver.c | 6 +- src/qemu/qemu_driver.c | 6 + src/uml/uml_driver.c | 4 + src/util/virthread.c | 293 +++++++++++++++++++++++- src/util/virthread.h | 51 ++++- src/util/virthreadpthread.c | 278 ----------------------- src/util/virthreadpthread.h | 49 ---- src/util/virthreadwin32.c | 396 --------------------------------- src/util/virthreadwin32.h | 53 ----- 16 files changed, 388 insertions(+), 823 deletions(-) delete mode 100644 src/util/virthreadpthread.c delete mode 100644 src/util/virthreadpthread.h delete mode 100644 src/util/virthreadwin32.c delete mode 100644 src/util/virthreadwin32.h -- 1.8.4.2 -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list