Arch linux kernel modules not loading or not found fix notes

instructions.sh

# boot from live disk

# mount user partition
mount /dev/sda3 /mnt

# it might under a different location, such as
# mount /dev/nvme0n1p3 /mnt

# chroot into partition
arch-chroot /mnt

# check current kernel version
uname -r

# check available kernels, it should show no folder for current kernel version
ls /lib/modules

# install latest kernel
pacman -Syu linux linux-headers

# check linux kernel version installed
pacman -Q | grep linux

# creates /boot/initramfs-linux-fallback.img
mkinitcpio -p linux

# generate initramfs for all kernels
# mkinitcpio -P
# if there's errors, run
# pacman -S linux
# and try mkinitcpio again

# check /boot is mounted in fstab, since it may not be updating correct kernel image if not mounted.
lsblk -o NAME,UUID,MOUNTPOINT
cat /etc/fstab
# if it doesn't exist, then add it. Use UUID from lsblk output
#UUID=1A3B-C3D4 					/boot		vfat		defaults 	0 2

# (optional) regenerate grub
exit
mount /dev/sda1 /mnt/boot
arch-chroot /mnt
grub-mkconfig -o /boot/grub/grub.cfg
# check path is correct
cat /boot/grub/grub.cfg | grep vmlinuz

# (optional) customize grub menu
sudo nano /etc/default/grub
GRUB_CMDLINE_LINUX_DEFAULT="loglevel=7"
GRUB_DISABLE_SUBMENU=y
GRUB_DEFAULT=saved
GRUB_SAVEDEFAULT=true
# regenerate with grub-mkconfig -o /boot/grub/grub.cfg

# check last modified date, it should show recently modified images
ls -l /boot/

# check available kernels, should show latest kernel
ls /lib/modules

# reboot and select latest kernel
reboot