append option to drive if the option is defined

if the value was '0', we did not append the option to the drive,
resulting in wrong command line if the qemu default of an option is not
'0'

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>

diff --git a/PVE/QemuServer.pm b/PVE/QemuServer.pm
index acd4047a62830099377e0bea0af1475bef27eb97..686c864ca9c1762e414ea57b481de5cdd0735c1d 100644 (file)
--- a/PVE/QemuServer.pm
+++ b/PVE/QemuServer.pm
@@ -1624,7 +1624,7 @@ sub print_drive_full {
     my $opts = '';
     my @qemu_drive_options = qw(heads secs cyls trans media format cache rerror werror aio discard);
     foreach my $o (@qemu_drive_options) {
-       $opts .= ",$o=$drive->{$o}" if $drive->{$o};
+       $opts .= ",$o=$drive->{$o}" if defined($drive->{$o});
     }
 
     # snapshot only accepts on|off