Merge autopkgtest-cloud:no-nohz into autopkgtest-cloud:master

[Brian Murray]

When adding the virtio_rng workaround I noticed an arm64 nohz workaround which isn't doing anything anymore and the original bug it was working around (LP: #1531768) is now closed.

Proof its not taking effect:

ubuntu@bdmurray-test-1531768:~$ uname -m
aarch64
ubuntu@bdmurray-test-1531768:~$ cat /proc/cmdline
BOOT_IMAGE=/boot/vmlinuz-5.19.0-15-generic root=UUID=cfe829f2-2ab5-42d9-8de4-87138700704d ro console=tty1 console=ttyS0
ubuntu@bdmurray-test-1531768:~$ grep CMDLINE /etc/default/grub
GRUB_CMDLINE_LINUX_DEFAULT="nohz=off"
GRUB_CMDLINE_LINUX=""
ubuntu@bdmurray-test-1531768:~$ grep "console=tty" /boot/grub/grub.cfg
        linux /boot/vmlinuz-5.19.0-15-generic root=UUID=cfe829f2-2ab5-42d9-8de4-87138700704d ro console=tty1 console=ttyS0
                linux /boot/vmlinuz-5.19.0-15-generic root=UUID=cfe829f2-2ab5-42d9-8de4-87138700704d ro console=tty1 console=ttyS0

[Paride Legovini (paride)]

LGTM, thanks!

review: Approve

diff --git a/charms/focal/autopkgtest-cloud-worker/autopkgtest-cloud/worker-config-production/setup-canonical.sh b/charms/focal/autopkgtest-cloud-worker/autopkgtest-cloud/worker-config-production/setup-canonical.sh
index b53dfac..d23f658 100644
--- a/charms/focal/autopkgtest-cloud-worker/autopkgtest-cloud/worker-config-production/setup-canonical.sh
+++ b/charms/focal/autopkgtest-cloud-worker/autopkgtest-cloud/worker-config-production/setup-canonical.sh
@@ -19,12 +19,6 @@ EOF
     . /etc/rc.local
 fi
 
-# work around arm64 lockups (LP: #1531768)
-if [ "$(uname -m)" = aarch64 ] && ! grep -q 'GRUB_CMDLINE_LINUX.*nohz-off' /etc/default/grub; then
-    sed -i '/GRUB_CMDLINE_LINUX_DEFAULT/ s/=".*$/="nohz=off"/' /etc/default/grub
-    update-grub
-fi
-
 # work around hung tasks timeout w/ virtio_rng (LP: #1989258)
 if grep -q kinetic /etc/lsb-release; then
     if [ "$(uname -m)" = x86_64 ] && ! grep -q 'GRUB_CMDLINE_LINUX=.*module_blacklist=virtio_rng' /etc/default/grub; then