On 10/13/21 05:02, Michal Prívozník wrote:
On 10/8/21 11:37 PM, Jim Fehlig wrote:
There have been countless reports from users concerned about the following
error reported by libvirtd when qemu domains are shutdown
internal error: End of file from qemu monitor
While the error is harmless, users often mistaken it for real problem with
their deployments. EOF from the monitor can't be entirely ignored since
other threads may be using the monitor and must be able to detect the EOF
condition.
One potential fix is to delay reporting EOF until the monitor is used
after EOF is detected. This patch adds a 'goteof' member to the
qemuMonitor structure, which is set when EOF is detected on the monitor
socket. If another thread later tries to send data on the monitor, the
EOF error is reported.
Signed-off-by: Jim Fehlig <jfehlig@xxxxxxxx>
---
An RFC patch to squelch qemu monitor EOF error messages on VM shutdown.
Previous discussions and information on testing of the patch can be
found in this thread
https://listman.redhat.com/archives/libvir-list/2021-September/msg00949.html
src/qemu/qemu_monitor.c | 29 ++++++++++++++++-------------
1 file changed, 16 insertions(+), 13 deletions(-)
diff --git a/src/qemu/qemu_monitor.c b/src/qemu/qemu_monitor.c
index 5fc23f13d3..751ec8ba6c 100644
--- a/src/qemu/qemu_monitor.c
+++ b/src/qemu/qemu_monitor.c
@@ -113,6 +113,7 @@ struct _qemuMonitor {
/* true if qemu no longer wants 'props' sub-object of object-add */
bool objectAddNoWrap;
+ bool goteof;
};
/**
@@ -526,10 +527,10 @@ qemuMonitorIO(GSocket *socket G_GNUC_UNUSED,
{
qemuMonitor *mon = opaque;
bool error = false;
- bool eof = false;
bool hangup = false;
virObjectRef(mon);
+ mon->goteof = false;
At this point, the monitor object is unlocked (see the line below). So
setting this flag outside is potentially dangerous. But, I don't think
we need to set ->goteof here at all, do we? I mean, the moment we see
EOF the monitor object will be disposed and not ever used again.
Agreed. I've removed it and sent a non-RFC version of the patch
https://listman.redhat.com/archives/libvir-list/2021-October/msg00664.html
As an update to the commentary in that patch, my tests have now survived 220
iterations.
Regards,
Jim
