Daniel P. Berrange 2cb0899eec Fix potential events deadlock when unref'ing virConnectPtr ... When the last reference to a virConnectPtr is released by libvirtd, it was possible for a deadlock to occur in the virDomainEventState functions. The virDomainEventStatePtr holds a reference on virConnectPtr for each registered callback. When removing a callback, the virUnrefConnect function is run. If this causes the last reference on the virConnectPtr to be released, then virReleaseConnect can be run, which in turns calls qemudClose. This function has a call to virDomainEventStateDeregisterConn which is intended to remove all callbacks associated with the virConnectPtr instance. This will try to grab a lock on virDomainEventState but this lock is already held. Deadlock ensues Thread 1 (Thread 0x7fcbb526a840 (LWP 23185)): Since each callback associated with a virConnectPtr holds a reference on virConnectPtr, it is impossible for the qemudClose method to be invoked while any callbacks are still registered. Thus the call to virDomainEventStateDeregisterConn must in fact be a no-op. Thus it is possible to just remove all trace of virDomainEventStateDeregisterConn and avoid the deadlock. * src/conf/domain_event.c, src/conf/domain_event.h, src/libvirt_private.syms: Delete virDomainEventStateDeregisterConn * src/libxl/libxl_driver.c, src/lxc/lxc_driver.c, src/qemu/qemu_driver.c, src/uml/uml_driver.c: Remove calls to virDomainEventStateDeregisterConn		2012-05-21 18:50:47 +01:00
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uml_conf.c	Attach vm-id to Open vSwitch interfaces.	2012-03-08 14:44:15 -05:00
uml_conf.h	Rename hash.h and hash.c to virhash.h and virhash.c	2012-01-26 14:11:13 +00:00
uml_driver.c	Fix potential events deadlock when unref'ing virConnectPtr	2012-05-21 18:50:47 +01:00
uml_driver.h	build: consistently indent preprocessor directives	2010-03-09 19:22:28 +01:00