[PATCH qemu-server v4 3/3] fix #7119: qm cleanup: wait for process exiting for up to 30 seconds

[Dominik Csapak <d.csapak@proxmox.com>]

When qmeventd detects a vm exiting, it starts 'qm cleanup'.

Since the vm process exits is sometimes not instant, wait up to 30
seconds here to start the cleanup process instead of immediately
aborting if the pid still exits. This prevented executing the hookscript
on the 'post-stop' phase when either
* the cleanup mechanism is still the old one
* the guest was powered down from inside, not via the API

This can be reproduced by e.g. passing through a usb device, which
delays the qemu process exit for a few seconds (for most devices).

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
---
changes from v3:
* adapt to indentation change of previous patch
* use non-deprecated vm_running_locally helper
* improve warning message

 src/PVE/CLI/qm.pm | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/src/PVE/CLI/qm.pm b/src/PVE/CLI/qm.pm
index 3c9e8812..a35d9f74 100755
--- a/src/PVE/CLI/qm.pm
+++ b/src/PVE/CLI/qm.pm
@@ -1101,7 +1101,7 @@ __PACKAGE__->register_method({
             60,
             sub {
                 my $conf = PVE::QemuConfig->load_config($vmid);
-                my $pid = PVE::QemuServer::check_running($vmid);
+                my $pid = PVE::QemuServer::Helpers::vm_running_locally($vmid);
 
                 if ($pid) {
                     # With a stop mode backup, we might run here into a running vm with a backup
@@ -1110,7 +1110,21 @@ __PACKAGE__->register_method({
                     die "skipping cleanup - 'backup' lock is present and vm is running again\n"
                         if $clean && $conf->{lock} && $conf->{lock} eq 'backup';
 
-                    die "vm still running\n";
+                    # wait for some time until the QEMU process exits after the QMP
+                    # 'SHUTDOWN' event, since this might not be instant
+
+                    my $timeout = 30;
+                    warn
+                        "QEMU process $pid for VM $vmid still running (or newly started), waiting up to $timeout seconds for it to exit\n";
+                    my $starttime = time();
+
+                    while ($pid && (time() - $starttime) < $timeout) {
+                        sleep(1);
+                        $pid = PVE::QemuServer::Helpers::vm_running_locally($vmid);
+                    }
+
+                    die "aborting cleanup, VM is still running after $timeout seconds\n"
+                        if $pid;
                 }
 
                 # Rollback already does cleanup when preparing and afterwards temporarily drops the
-- 
2.47.3