mirror of
https://gitlab.com/libvirt/libvirt.git
synced 2024-12-23 06:05:27 +00:00
Libvirt provides a portable, long term stable C API for managing the
virtualization technologies provided by many operating systems. It
includes support for QEMU, KVM, Xen, LXC, bhyve, Virtuozzo, VMware
vCenter and ESX, VMware Desktop, Hyper-V, VirtualBox and the POWER
Hypervisor.
e22de286b1
The functions in virCommand() after fork() must be careful with regard
to accessing any mutexes that may have been locked by other threads in
the parent process. It is possible that another thread in the parent
process holds the lock for the virQEMUDriver while fork() is called.
This leads to a deadlock in the child process when
'virQEMUDriverGetConfig(driver)' is called and therefore the handshake
never completes between the child and the parent process. Ultimately
the virDomainObjectPtr will never be unlocked.
It gets much worse if the other thread of the parent process, that
holds the lock for the virQEMUDriver, tries to lock the already locked
virDomainObject. This leads to a completely unresponsive libvirtd.
It's possible to reproduce this case with calling 'virsh start XXX'
and 'virsh managedsave XXX' in a tight loop for multiple domains.
This commit fixes the deadlock in the same way as it is described in
commit
|
||
---|---|---|
.gnulib@94386a1366 | ||
build-aux | ||
daemon | ||
docs | ||
examples | ||
gnulib | ||
include/libvirt | ||
m4 | ||
po | ||
src | ||
tests | ||
tools | ||
.ctags | ||
.dir-locals.el | ||
.gitignore | ||
.gitmodules | ||
.mailmap | ||
AUTHORS.in | ||
autobuild.sh | ||
autogen.sh | ||
bootstrap | ||
bootstrap.conf | ||
cfg.mk | ||
ChangeLog-old | ||
config-post.h | ||
configure.ac | ||
COPYING | ||
COPYING.LESSER | ||
HACKING | ||
libvirt-admin.pc.in | ||
libvirt-lxc.pc.in | ||
libvirt-qemu.pc.in | ||
libvirt.pc.in | ||
libvirt.spec.in | ||
Makefile.am | ||
Makefile.nonreentrant | ||
mingw-libvirt.spec.in | ||
README | ||
README-hacking | ||
run.in | ||
TODO |
LibVirt : simple API for virtualization Libvirt is a C toolkit to interact with the virtualization capabilities of recent versions of Linux (and other OSes). It is free software available under the GNU Lesser General Public License. Virtualization of the Linux Operating System means the ability to run multiple instances of Operating Systems concurrently on a single hardware system where the basic resources are driven by a Linux instance. The library aim at providing long term stable C API initially for the Xen paravirtualization but should be able to integrate other virtualization mechanisms if needed. Daniel Veillard <veillard@redhat.com>