** Description changed: + [Impact] + + * Fix a potential deadlock + + * The trigger is essentially a race, so it is rare and repro unreliable + + [Test Case] + + * This is the hard part for this issue, essentially changing NWFilters + through libvirt. The reporter hits it on removing a guest, but it is + hard to make a recipe by that. + + * We have to fall back to general regression checks with an extra eye on + NWFilter handling + + + [Regression Potential] + + * The only bad part is the hard repro, everything else seems to make this + low risk + - the patch is small + - the patch got no follow on fix in 2 years (so it is very stable) + - it unlocks earlier (so deadlocks are less likely) + - there is no data issue (being unlocked early) as explained in the + patch + + [Other Info] + + * n/a + + --- + When deleting a VM, libvirt-bin intermittently hits a deadlock in nwfilter instantiation code. This is fixed in libvirt upstream, but the below commit is not cherrypicked in ubuntu yet: https://github.com/libvirt/libvirt/commit/2f5e24ba00d93c25b87561cb1f5259de175d70f9 Thread 5 (Thread 0x7f2ce1c4b700 (LWP 13866)): #0 __lll_lock_wait () at ../sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:135 #1 0x00007f2cee30ce42 in __GI___pthread_mutex_lock (mutex=0x7f2c980008d0) at ../nptl/pthread_mutex_lock.c:115 #2 0x00007f2cc7d7a62f in virNWFilterLockIface () from /usr/lib/libvirt/connection-driver/libvirt_driver_nwfilter.so #3 0x00007f2cc7d6ebf5 in ?? () from /usr/lib/libvirt/connection-driver/libvirt_driver_nwfilter.so #4 0x00007f2cc7d6f84c in virNWFilterTeardownFilter () from /usr/lib/libvirt/connection-driver/libvirt_driver_nwfilter.so ---Type <return> to continue, or q <return> to quit--- #5 0x00007f2ceea32f0c in virDomainConfVMNWFilterTeardown () from /usr/lib/x86_64-linux-gnu/libvirt.so.0 #6 0x00007f2cc73d5a86 in qemuProcessStop () from /usr/lib/libvirt/connection-driver/libvirt_driver_qemu.so #7 0x00007f2cc7420577 in ?? () from /usr/lib/libvirt/connection-driver/libvirt_driver_qemu.so #8 0x00007f2ceea857cf in virDomainDestroy () from /usr/lib/x86_64-linux-gnu/libvirt.so.0 #9 0x000055c4ba3fe9db in ?? () #10 0x00007f2ceeaf8f69 in virNetServerProgramDispatch () from /usr/lib/x86_64-linux-gnu/libvirt.so.0 #11 0x00007f2ceeaf4478 in ?? () from /usr/lib/x86_64-linux-gnu/libvirt.so.0 #12 0x00007f2cee9eb566 in ?? () from /usr/lib/x86_64-linux-gnu/libvirt.so.0 #13 0x00007f2cee9eaae8 in ?? () from /usr/lib/x86_64-linux-gnu/libvirt.so.0 #14 0x00007f2cee30a6ba in start_thread (arg=0x7f2ce1c4b700) at pthread_create.c:333 #15 0x00007f2cee04041d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109 - Thread 17 (Thread 0x7f2cc2801700 (LWP 8866)): #0 __lll_lock_wait () at ../sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:135 #1 0x00007f2cee30ce42 in __GI___pthread_mutex_lock (mutex=0x7f2cc7f8d280) at ../nptl/pthread_mutex_lock.c:115 #2 0x00007f2cc7d6f6d3 in virNWFilterInstantiateFilterLate () from /usr/lib/libvirt/connection-driver/libvirt_driver_nwfilter.so #3 0x00007f2cc7d7a9b2 in ?? () from /usr/lib/libvirt/connection-driver/libvirt_driver_nwfilter.so #4 0x00007f2cee9eab12 in ?? () from /usr/lib/x86_64-linux-gnu/libvirt.so.0 #5 0x00007f2cee30a6ba in start_thread (arg=0x7f2cc2801700) at pthread_create.c:333 #6 0x00007f2cee04041d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1753604 Title: libvirt-bin nwfilter deadlock To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1753604/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
