Re: [libvirt] [PATCH] qemu: Return meaningful error when qemu dies early
On Mon, Mar 17, 2014 at 13:21:56 +0100, Jiri Denemark wrote:
https://bugzilla.redhat.com/show_bug.cgi?id=844378
When qemu dies early after connecting to its monitor but before we
actually try to read something from the monitor, we would just fail
domain start with useless message:
"An error occurred, but the cause is unknown"
This is because the real error gets reported in a monitor EOF handler
executing within libvirt's event loop.
The fix is to take any error set in qemuMonitor structure and propagate
it into the thread-local error when qemuMonitorClose is called and no
thread-local error is set.
Signed-off-by: Jiri Denemark <jdenemar(a)redhat.com>
---
Oops, I forgot to send notes:
To reproduce the issue, just apply the following patch and kill
qemu process while libvirtd is sleeping:
diff --git i/src/qemu/qemu_process.c w/src/qemu/qemu_process.c
index 400625a..3b77ecc 100644
--- i/src/qemu/qemu_process.c
+++ w/src/qemu/qemu_process.c
@@ -1415,6 +1415,9 @@ qemuConnectMonitor(virQEMUDriverPtr driver, virDomainObjPtr vm, int
logfd)
if (mon)
ignore_value(qemuMonitorSetDomainLog(mon, logfd));
+ VIR_DEBUG("Sleeping");
+ sleep(5);
+
virObjectLock(vm);
virObjectUnref(vm);
priv->monStart = 0;