If you wish to add to it 'manually', you can use the APPEND variable, in for example your conf/local.conf
APPEND += "oops=panic panic=5"
Then, depending on which boot mechanism you're using, you will need to force building of the boot configuration, to include the change.
eg.
$ bitbake -C populate_sysroot grub-efi
$ grep panic build/tmp/work/genericx86_64-poky-linux/core-image-minimal/1.0-r0/core-image-minimal-1.0/hddimg/EFI/BOOT/grub.cfg
linux /vmlinuz LABEL=boot root=/dev/ram0 oops=panic panic=5
Unfortunately, as is sometimes the case with Yocto, the left hand doesn't know what the right is doing.
qb_kernel_cmdline_append = vga=0 uvesafb.mode_option=640x480-32 oprofile.timer=1 uvesafb.task_timeout=-1
This likely needs tweaking below -
$ grep QB_KERNEL_CMDLINE_APPEND meta/conf/machine/include/qemuboot-x86.inc
QB_KERNEL_CMDLINE_APPEND = "vga=0 uvesafb.mode_option=${UVESA_MODE} oprofile.timer=1 uvesafb.task_timeout=-1"
Similarly, the append is not present, in the wic image -
$ bitbake -C image_wic core-image-minimal
$ sudo losetup -o $((2048*512)) --show -f core-image-minimal-genericx86-64.wic
/dev/loop1
$ mkdir /mnt/loop1
$ sudo mount /dev/loop1 /mnt/loop1
$ cat /mnt/loop1/EFI/BOOT/grub.cfg
serial --unit=0 --speed=115200 --word=8 --parity=no --stop=1
default=boot
timeout=5
menuentry 'boot'{
linux /bzImage root=PARTUUID=c496bfa5-a796-473c-bb6f-50d7b0161295 rootwait rootfstype=ext4 console=ttyS0,115200 console=tty0
}
This can be tweaked in the 'kickstart' file below -
$ grep append meta-yocto-bsp/wic/genericx86.wks
bootloader --ptable gpt --timeout=5 --append="rootfstype=ext4 console=ttyS0,115200 console=tty0"
