Re: [PATCH v3] rootfs: Fix support for rootfstype= when root= is given

[Greg KH]

On Sun, Nov 19, 2023 at 08:12:48PM -0500, Stefan Berger wrote:
> Documentation/filesystems/ramfs-rootfs-initramfs.rst states:
> 
>   If CONFIG_TMPFS is enabled, rootfs will use tmpfs instead of ramfs by
>   default.  To force ramfs, add "rootfstype=ramfs" to the kernel command
>   line.
> 
> This currently does not work when root= is provided since then
> saved_root_name contains a string and rootfstype= is ignored. Therefore,
> ramfs is currently always chosen when root= is provided.
> 
> The current behavior for rootfs's filesystem is:
> 
>    root=       | rootfstype= | chosen rootfs filesystem
>    ------------+-------------+--------------------------
>    unspecified | unspecified | tmpfs
>    unspecified | tmpfs       | tmpfs
>    unspecified | ramfs       | ramfs
>     provided   | ignored     | ramfs
> 
> rootfstype= should be respected regardless whether root= is given,
> as shown below:
> 
>    root=       | rootfstype= | chosen rootfs filesystem
>    ------------+-------------+--------------------------
>    unspecified | unspecified | tmpfs  (as before)
>    unspecified | tmpfs       | tmpfs  (as before)
>    unspecified | ramfs       | ramfs  (as before)
>     provided   | unspecified | ramfs  (compatibility with before)
>     provided   | tmpfs       | tmpfs  (new)
>     provided   | ramfs       | ramfs  (new)
> 
> This table represents the new behavior.
> 
> Fixes: 6e19eded3684 ("initmpfs: use initramfs if rootfstype= or root=  specified")
> Cc: <stable@xxxxxxxxxxxxxxx>
> Signed-off-by: Rob Landley <rob@xxxxxxxxxxx>
> Link: https://lore.kernel.org/lkml/8244c75f-445e-b15b-9dbf-266e7ca666e2@xxxxxxxxxxx/
> Signed-off-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>

Acked-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

Who should take this patch?  Me?  Or someone else?

thanks,

greg k-h