Re: [libvirt] [PATCH] qemu: fix sometimes error overwrite when we fail to start/migrate/restore

On Thu, Mar 19, 2015 at 11:14:39AM +0800, Luyao Huang wrote: > https://bugzilla.redhat.com/show_bug.cgi?id=1196934 > Adding a comment in the bugzilla saying you posted a patch (with a link to libvir-list archives) can be helpful. Otherwise they might send the exact same patch - if your was not merged yet, or it was rejected.

> When start/migrate/restore a vm failed, libvirt will try to catch the log in Libvirt only uses the error from qemu if qemu exits during the startup. Start/migrate/restore could fail for other reasons. > /var/log/libvirt/qemu/vm.log and output them before. However we add a check in > qemuDomainObjExitMonitor after commit dc2fd51f, this will overwrite > the error set in priv->mon which has set by qemuMonitorIO (a qemu monitor > I/O event callback function). qemuMonitorIO only stores the error in mon->lastError. It's the functions like qemuMonitorSend and qemuMonitorClose that take this error and set it via virSetError.

> Add a check in qemuDomainObjExitMonitor, if there is an error have been > set by other function, we won't overwrite it. Reworded as: When qemu exits during startup, libvirt includes the error from /var/log/libvirt/qemu/vm.log in the error message: $ virsh start test3 error: Failed to start domain test3 error: internal error: early end of file from monitor: possible problem: 2015-02-27T03:03:16.985494Z qemu-kvm: -numa memdev is not supported by machine rhel6.5.0 The check for domain liveness added to qemuDomainObjExitMonitor in commit dc2fd51f sometimes overwrites this error: $ virsh start test3 error: Failed to start domain test3 error: operation failed: domain is no longer running Fix the check to only report an error if there is none set.

> Signed-off-by: Luyao Huang <lhuang(a)redhat.com&gt; > --- > src/qemu/qemu_domain.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > ACK and pushed. Jan

> diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c > index 2eacef2..41d1263 100644 > --- a/src/qemu/qemu_domain.c > +++ b/src/qemu/qemu_domain.c > @@ -1609,8 +1609,9 @@ int qemuDomainObjExitMonitor(virQEMUDriverPtr driver, > { > qemuDomainObjExitMonitorInternal(driver, obj); > if (!virDomainObjIsActive(obj)) { > - virReportError(VIR_ERR_OPERATION_FAILED, "%s", > - _("domain is no longer running")); > + if (!virGetLastError()) > + virReportError(VIR_ERR_OPERATION_FAILED, "%s", > + _("domain is no longer running")); > return -1; > } > return 0; > -- > 1.8.3.1 > > -- > libvir-list mailing list > libvir-list(a)redhat.com > https://www.redhat.com/mailman/listinfo/libvir-list