[pve-devel] [PATCH qemu-server v3] fix #2788: do not resume vms after backup if they were paused before

[Dominik Csapak]

by checking if the vm is paused at the beginning and skipping the resume
now we also skip the qga freeze/thaw (which cannot work if the vm is
paused)

moved the 'vm_is_paused' sub from the api to PVE/QemuServer.pm so it is
available everywhere we need it.

since a suspend backup would pause the vm anyway, we can skip that step
also

Signed-off-by: Dominik Csapak <d.csapak at proxmox.com>
---
changes to v2:
* actually include code changes (git add is not optional), sry for the noise

 PVE/API2/Qemu.pm         | 14 ++------------
 PVE/QemuServer.pm        | 10 ++++++++++
 PVE/VZDump/QemuServer.pm | 11 +++++++++--
 3 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/PVE/API2/Qemu.pm b/PVE/API2/Qemu.pm
index e2d2d67..623c998 100644
--- a/PVE/API2/Qemu.pm
+++ b/PVE/API2/Qemu.pm
@@ -2402,16 +2402,6 @@ __PACKAGE__->register_method({
 	return $rpcenv->fork_worker('qmreset', $vmid, $authuser, $realcmd);
     }});
 
-my sub vm_is_paused {
-    my ($vmid) = @_;
-    my $qmpstatus = eval {
-	PVE::QemuConfig::assert_config_exists_on_node($vmid);
-	mon_cmd($vmid, "query-status");
-    };
-    warn "$@\n" if $@;
-    return $qmpstatus && $qmpstatus->{status} eq "paused";
-}
-
 __PACKAGE__->register_method({
     name => 'vm_shutdown',
     path => '{vmid}/status/shutdown',
@@ -2480,7 +2470,7 @@ __PACKAGE__->register_method({
 	#
 	# checking the qmp status here to get feedback to the gui/cli/api
 	# and the status query should not take too long
-	if (vm_is_paused($vmid)) {
+	if (PVE::QemuServer::vm_is_paused($vmid)) {
 	    if ($param->{forceStop}) {
 		warn "VM is paused - stop instead of shutdown\n";
 		$shutdown = 0;
@@ -2556,7 +2546,7 @@ __PACKAGE__->register_method({
 	my $node = extract_param($param, 'node');
 	my $vmid = extract_param($param, 'vmid');
 
-	die "VM is paused - cannot shutdown\n" if vm_is_paused($vmid);
+	die "VM is paused - cannot shutdown\n" if PVE::QemuServer::vm_is_paused($vmid);
 
 	die "VM $vmid not running\n" if !PVE::QemuServer::check_running($vmid);
 
diff --git a/PVE/QemuServer.pm b/PVE/QemuServer.pm
index 54278e5..d7ee05f 100644
--- a/PVE/QemuServer.pm
+++ b/PVE/QemuServer.pm
@@ -7382,4 +7382,14 @@ sub complete_migration_storage {
     return $res;
 }
 
+sub vm_is_paused {
+    my ($vmid) = @_;
+    my $qmpstatus = eval {
+	PVE::QemuConfig::assert_config_exists_on_node($vmid);
+	mon_cmd($vmid, "query-status");
+    };
+    warn "$@\n" if $@;
+    return $qmpstatus && $qmpstatus->{status} eq "paused";
+}
+
 1;
diff --git a/PVE/VZDump/QemuServer.pm b/PVE/VZDump/QemuServer.pm
index b322701..b5e74d3 100644
--- a/PVE/VZDump/QemuServer.pm
+++ b/PVE/VZDump/QemuServer.pm
@@ -62,8 +62,11 @@ sub prepare {
 	if defined($conf->{name});
 
     $self->{vm_was_running} = 1;
+    $self->{vm_was_paused} = 0;
     if (!PVE::QemuServer::check_running($vmid)) {
 	$self->{vm_was_running} = 0;
+    } elsif (PVE::QemuServer::vm_is_paused($vmid)) {
+	$self->{vm_was_paused} = 1;
     }
 
     $task->{hostname} = $conf->{name};
@@ -176,12 +179,16 @@ sub start_vm {
 sub suspend_vm {
     my ($self, $task, $vmid) = @_;
 
+    return if $self->{vm_was_paused};
+
     $self->cmd ("qm suspend $vmid --skiplock");
 }
 
 sub resume_vm {
     my ($self, $task, $vmid) = @_;
 
+    return if $self->{vm_was_paused};
+
     $self->cmd ("qm resume $vmid --skiplock");
 }
 
@@ -794,7 +801,7 @@ sub _get_task_devlist {
 
 sub qga_fs_freeze {
     my ($self, $task, $vmid) = @_;
-    return if !$self->{vmlist}->{$vmid}->{agent} || $task->{mode} eq 'stop' || !$self->{vm_was_running};
+    return if !$self->{vmlist}->{$vmid}->{agent} || $task->{mode} eq 'stop' || !$self->{vm_was_running} || $self->{vm_was_paused};
 
     if (!PVE::QemuServer::qga_check_running($vmid, 1)) {
 	$self->loginfo("skipping guest-agent 'fs-freeze', agent configured but not running?");
@@ -872,7 +879,7 @@ sub register_qmeventd_handle {
 sub resume_vm_after_job_start {
     my ($self, $task, $vmid) = @_;
 
-    return if !$self->{vm_was_running};
+    return if !$self->{vm_was_running} || $self->{vm_was_paused};
 
     if (my $stoptime = $task->{vmstoptime}) {
 	my $delay = time() - $task->{vmstoptime};
-- 
2.20.1