Re: [PATCH] fs: Add 'rootfsflags' to set rootfs mount options

From: Rob Landley
Date: Sat Aug 09 2025 - 11:02:39 EST


On 8/7/25 20:51, Lichen Liu wrote:
This patch introduces a new kernel command-line parameter, rootfsflags,
which allows passing specific mount options directly to the rootfs when
it is first mounted. This gives users control over the rootfs behavior.

Works for me. In an i486 mkroot build against stock 6.16 with this patch:

$ root/i486/run-qemu.sh
...
# grep rootfs /proc/mounts
rootfs / rootfs rw,size=125728k,nr_inodes=31432 0 0
# df
Filesystem 1K-blocks Used Available Use% Mounted on
rootfs 125728 764 124964 1% /
dev 125728 0 125728 0% /dev


$ KARGS="rootfsflags=size=1m" root/i486/run-qemu.sh
...
# grep rootfs /proc/mounts
rootfs / rootfs rw,size=1024k,nr_inodes=31432 0 0
# df
Filesystem 1K-blocks Used Available Use% Mounted on
rootfs 1024 764 260 75% /
dev 125728 0 125728 0% /dev

Tested-by: Rob Landley <rob@xxxxxxxxxxx>

Rob