From eb5e482ded9ae6aeb6575de9441b79b90a5de531 Mon Sep 17 00:00:00 2001
From: Oguz Bektas <o.bektas@proxmox.com>
Date: Tue, 7 Jan 2020 16:55:18 +0100
Subject: [PATCH] vmconfig_apply_pending: add error handling

wrap around code which can possibly fail in evals to handle them
gracefully, and log errors.

note: this results in a change of behavior in the API. since errors
are handled gracefully instead of "die"ing, when there is a pending
change which cannot be applied for some reason, it will get logged in
the tasklog but the vm will continue booting regardless. the
non-applied change will stay in the pending section of the
configuration.

Signed-off-by: Oguz Bektas <o.bektas@proxmox.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
 PVE/API2/Qemu.pm  |  6 ++---
 PVE/QemuServer.pm | 61 ++++++++++++++++++++++++++++++++---------------
 2 files changed, 45 insertions(+), 22 deletions(-)

diff --git a/PVE/API2/Qemu.pm b/PVE/API2/Qemu.pm
index 5bae513..e853a83 100644
--- a/PVE/API2/Qemu.pm
+++ b/PVE/API2/Qemu.pm
@@ -1242,13 +1242,13 @@ my $update_vm_api  = sub {
 
 	    $conf = PVE::QemuConfig->load_config($vmid); # update/reload
 
+	    my $errors = {};
 	    if ($running) {
-		my $errors = {};
 		PVE::QemuServer::vmconfig_hotplug_pending($vmid, $conf, $storecfg, $modified, $errors);
-		raise_param_exc($errors) if scalar(keys %$errors);
 	    } else {
-		PVE::QemuServer::vmconfig_apply_pending($vmid, $conf, $storecfg, $running);
+		PVE::QemuServer::vmconfig_apply_pending($vmid, $conf, $storecfg, $running, $errors);
 	    }
+	    raise_param_exc($errors) if scalar(keys %$errors);
 
 	    return;
 	};
diff --git a/PVE/QemuServer.pm b/PVE/QemuServer.pm
index 2b68d81..2de8376 100644
--- a/PVE/QemuServer.pm
+++ b/PVE/QemuServer.pm
@@ -4977,23 +4977,39 @@ sub vmconfig_delete_or_detach_drive {
 
 
 sub vmconfig_apply_pending {
-    my ($vmid, $conf, $storecfg) = @_;
+    my ($vmid, $conf, $storecfg, $errors) = @_;
+
+    my $add_apply_error = sub {
+	my ($opt, $msg) = @_;
+	my $err_msg = "unable to apply pending change $opt : $msg";
+	$errors->{$opt} = $err_msg;
+	warn $err_msg;
+    };
 
     # cold plug
 
     my $pending_delete_hash = PVE::QemuConfig->parse_pending_delete($conf->{pending}->{delete});
     foreach my $opt (sort keys %$pending_delete_hash) {
-	die "internal error" if $opt =~ m/^unused/;
 	my $force = $pending_delete_hash->{$opt}->{force};
-	$conf = PVE::QemuConfig->load_config($vmid); # update/reload
-	if (!defined($conf->{$opt})) {
-	    PVE::QemuConfig->remove_from_pending_delete($conf, $opt);
-	    PVE::QemuConfig->write_config($vmid, $conf);
-	} elsif (is_valid_drivename($opt)) {
-	    vmconfig_delete_or_detach_drive($vmid, $storecfg, $conf, $opt, $force);
-	    PVE::QemuConfig->remove_from_pending_delete($conf, $opt);
-	    delete $conf->{$opt};
-	    PVE::QemuConfig->write_config($vmid, $conf);
+	eval {
+	    die "internal error" if $opt =~ m/^unused/;
+	    $conf = PVE::QemuConfig->load_config($vmid); # update/reload
+	    if (!defined($conf->{$opt})) {
+		PVE::QemuConfig->remove_from_pending_delete($conf, $opt);
+		PVE::QemuConfig->write_config($vmid, $conf);
+	    } elsif (is_valid_drivename($opt)) {
+		vmconfig_delete_or_detach_drive($vmid, $storecfg, $conf, $opt, $force);
+		PVE::QemuConfig->remove_from_pending_delete($conf, $opt);
+		delete $conf->{$opt};
+		PVE::QemuConfig->write_config($vmid, $conf);
+	    } else {
+		PVE::QemuConfig->remove_from_pending_delete($conf, $opt);
+		delete $conf->{$opt};
+		PVE::QemuConfig->write_config($vmid, $conf);
+	    }
+	};
+	if (my $err = $@) {
+	    $add_apply_error->($opt, $err);
 	} else {
 	    PVE::QemuConfig->remove_from_pending_delete($conf, $opt);
 	    delete $conf->{$opt};
@@ -5006,17 +5022,24 @@ sub vmconfig_apply_pending {
     foreach my $opt (keys %{$conf->{pending}}) { # add/change
 	$conf = PVE::QemuConfig->load_config($vmid); # update/reload
 
-	if (defined($conf->{$opt}) && ($conf->{$opt} eq $conf->{pending}->{$opt})) {
-	    # skip if nothing changed
-	} elsif (is_valid_drivename($opt)) {
-	    vmconfig_register_unused_drive($storecfg, $vmid, $conf, parse_drive($opt, $conf->{$opt}))
-		if defined($conf->{$opt});
-	    $conf->{$opt} = $conf->{pending}->{$opt};
+	eval {
+	    if (defined($conf->{$opt}) && ($conf->{$opt} eq $conf->{pending}->{$opt})) {
+		# skip if nothing changed
+	    } elsif (is_valid_drivename($opt)) {
+		vmconfig_register_unused_drive($storecfg, $vmid, $conf, parse_drive($opt, $conf->{$opt}))
+		    if defined($conf->{$opt});
+		$conf->{$opt} = $conf->{pending}->{$opt};
+	    } else {
+		$conf->{$opt} = $conf->{pending}->{$opt};
+	    }
+	};
+	if (my $err = $@) {
+	    $add_apply_error->($opt, $err);
 	} else {
-	    $conf->{$opt} = $conf->{pending}->{$opt};
+	    $conf->{$opt} = delete $conf->{pending}->{$opt};
+	    PVE::QemuConfig->cleanup_pending($conf);
 	}
 
-	delete $conf->{pending}->{$opt};
 	PVE::QemuConfig->write_config($vmid, $conf);
     }
 }
-- 
2.39.2