Re: [Trinux-talk] (Solution) Alternative kernels and trinux-uml

[Matthew F. <mf...@ci...>]

Thanks for tracking this down -- if there is enough interest I can create
a trinux-uml mailing list so we can take this off the trinux-talk list.

I really haven't done a formal release announcement but there might be
some interest in using a UML version of trinux for various things.

- mdf

> Date: Tue, 12 Feb 2002 01:06:31 -0500 (EST)
> From: Jonathan Rosenbaum <mma...@ya...>
> To: Bill Burdick <bi...@ap...>
> Cc: tri...@li..., Matthew Franz <mf...@ci...>
> Subject: Re: [Trinux-talk] (Solution) Alternative kernels and trinux-uml
>
> Hi trinux-talkers,
>
> Yes, the solution did come from looking at Bill's kernel config
> for his uml.  This is a really interesting problem.  What is happening is
> that the order in which the VFS (Virtual File System) is being checked by
> the kernel for filesystem type determines when the bug occurs.
>
> In this case cramfs is the culprit.  Notice what is happening below:
>
> RAMDISK: Minix filesystem found at block 0
> RAMDISK: Loading 4096 blocks [1 disk] into ram disk... done.
> Freeing initrd memory: 4096k freed
> cramfs: wrong magic
> MINIX-fs: mounting unchecked file system, running fsck is recommended.
> VFS: Mounted root (minix filesystem).
> Warning: unable to open an initial console.
> Kernel panic: No init found.  Try passing init= option to kernel.
>
> When CONFIG_CRAMFS is made into a module or not included, the problem
> disappears.  But when I ran the same uml kernel with cramfs on an initrd
> which has ext2 fs, the problem also disappears.  This is because the
> kernel uses an order when checking the fs.  You can look at this order in
> /proc/filesystems.
>
> For instance:
>
> nodev   rootfs
> nodev   bdev
> nodev   proc
> nodev   sockfs
> nodev   tmpfs
> nodev   shm
> nodev   pipefs
> nodev   binfmt_misc
>         ext2
>         cramfs
>         minix
>         umsdos
>         msdos
>
> An initrd with minix will fail in the above situation, but an initrd with
> ext2 won't.  So at this point if you want minix or msdos you can't have
> cramfs included in the kernel.  This may be related to a documented bug in
> cramfs, regardless, a simple solution would be to put cramf at the end of
> the VFS check list since it would be nice to have cramfs and everything
> else, too.
>
> Thanks for the config.  I am going to be posting a bug report at
> user-mode-linux-devel, if you notice another fs causing this VFS problem
> contact me, or add to this post.
>
> Regards,
>
>
> Jonathan
>
>
>
> _______________________________________________
> Trinux-talk mailing list
> Tri...@li...
> https://lists.sourceforge.net/lists/listinfo/trinux-talk
>