In case when the hypervisor does report the reason for the I/O error as
an unstable string to display to users we can add a @reason possibility
for the I/O error event noting that the error is available.
Add 'hypervisor-message' as a reason enumeration value and document it
to instruct users to look at the logs or virDomainGetMessages().
The resulting event looks like:
event 'io-error' for domain 'cd': /dev/mapper/errdev0 (virtio-disk0) report due to hypervisor-message
Users then can look at the virDomainGetMessages() API:
I/O error: disk='vda', index='1', path='/dev/mapper/errdev0', timestamp='2025-01-28 15:47:52.776+0000', message'Input/output error'
Or at the VM log file:
2025-01-28 15:47:52.776+0000: IO error device='virtio-disk0' node-name='libvirt-1-storage' reason='Input/output error'
Signed-off-by: Peter Krempa <pkrempa@xxxxxxxxxx>
---
include/libvirt/libvirt-domain.h | 4 ++++
src/qemu/qemu_process.c | 2 ++
2 files changed, 6 insertions(+)
diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h
index 941e67aab1..2615d7b76a 100644
--- a/include/libvirt/libvirt-domain.h
+++ b/include/libvirt/libvirt-domain.h
@@ -4812,6 +4812,10 @@ typedef void (*virConnectDomainEventIOErrorCallback)(virConnectPtr conn,
* - "enospc": The I/O error is known to be caused by an ENOSPC condition in
* the host. Resizing the disk source to be larger will allow the
* guest to be resumed as if nothing happened.
+ * - "hypervisor-message": The hypervisor reported a string description of the
+ * I/O error. The errors are usually logged into the
+ * domain log file or the last instance of the error
+ * string can be queried via virDomainGetMessages().
*
* Since: 0.8.1
*/
diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index e9342287ab..cf6e0517ef 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -862,6 +862,8 @@ qemuProcessHandleIOError(qemuMonitor *mon G_GNUC_UNUSED,
if (nospace)
eventReason = "enospc";
+ else if (reason)
+ eventReason = "hypervisor-message";
ioErrorEvent = virDomainEventIOErrorNewFromObj(vm, eventPath, eventAlias, action);
ioErrorEvent2 = virDomainEventIOErrorReasonNewFromObj(vm, eventPath, eventAlias, action, eventReason);
--
2.48.1
