ts-debian-hvm-install: Allow udev failure in install media

Kernel in "debian-12.1.0-amd64-netinst.iso" prevent debian installer
from booting. Early on, it does `udevadm trigger --action=add`, which
fails, the same way as the following runes fails:

$ cat /sys/devices/virtual/input/input2/name
Xen Virtual Keyboard
$ echo add > /sys/devices/virtual/input/input2/uevent
[   25.884403] synth uevent: /devices/virtual/input/input2: failed to send uevent
[   25.916498] input input2: uevent: failed to send synthetic uevent: -12
sh: write error: Cannot allocate memory
$ uname -a
Linux (none) 6.1.0-10-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.38-1 (2023-07-14) x86_64 GNU/Linux

This doesn't looks like a new issue, Debian Buster ISO seems to do the
same thing (early boot command, and error in Linux logs), so it's
probable that now `udevadm trigger --action=add` return an error when
there's a failure.

Bug report in the kernel and in Debian:
    https://bugzilla.kernel.org/show_bug.cgi?id=207695
    https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=983357

One way to workaround the issue is to remove the vkb device, with xl's
"vkb_device=0", but libvirt doesn't have support for this config
option.

The second option is to edit the installation media, and allow the
failure.

Once installed, the guest boot fine.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>

diff --git a/ts-debian-hvm-install b/ts-debian-hvm-install
index 4deb443e1f8c95788271f621a7f472adee386d7f..44eb3ab1dfe13b3801204fc05b92ffde836dbef9 100755 (executable)
--- a/ts-debian-hvm-install
+++ b/ts-debian-hvm-install
@@ -174,13 +174,14 @@ sub isolinux_cfg () {
 END
 }
 
-sub prepare_initrd ($$$) {
-    my ($initrddir,$newiso,$preseed_file_path) = @_;
+sub prepare_initrd ($$$$) {
+    my ($initrddir,$newiso,$preseed_file_path,$extra_rune) = @_;
     return <<"END";
       rm -rf $initrddir
       mkdir $initrddir
       cd $initrddir
       gzip -d < $newiso$ramdisk | cpio --extract --make-directories --no-absolute-filename
+      $extra_rune
       cp $preseed_file_path preseed.cfg
       find . | cpio -H newc --create | gzip -9 > $newiso$ramdisk
       cd -
@@ -268,7 +269,17 @@ sub prep () {
         target_putfilecontents_root_stash($ho, 10, preseed(),
                                           $preseed_file_path);
 
-        $cmds = prepare_initrd($initrddir,$newiso,$preseed_file_path);
+        my $extra_preseed_rune = '';
+        if ($gsuite =~ m/bookworm/) {
+            # Xen Virtual Keyboard initialisation fails and return ENOMEM
+            # https://bugzilla.kernel.org/show_bug.cgi?id=207695
+            # https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=983357
+            $extra_preseed_rune .= <<END;
+sed -i '/udevadm trigger --action=add/s/\$/ ||:/' lib/debian-installer/start-udev
+END
+        }
+        $cmds = prepare_initrd($initrddir,$newiso,$preseed_file_path,
+            $extra_preseed_rune);
         target_cmd_root($ho, $cmds, $isotimeout);
 
         target_putfilecontents_root_stash($ho, 10, grub_cfg(),