Re: [User-mode-linux-devel] New root_fs; problems with Toms Root/boot (libc5)

[William S. <wst...@po...>]

Good morning, Jeff,

On Sun, 18 Jun 2000, Jeff Dike wrote:

> > Try booting with 'devfs=nomount' and see if it  works better.

	OK, that helped.

> I forgot to mention that you'll also need to add a ubd device or two (block 
> major 98) to /dev.

	That didn't seem to make a difference to my current problem;
/sbin/init seems to execute rc.S but not get any further.  I added an
"echo Exiting rc.S" to the end and that shows up on the screen, but the
corresponding "entering rc.M" does not show up on the screen.  Init and
the tracing thread start fighting for CPU time.
	Here's a snippet from strace -p 6081 (the tracing thread).  6083
is init.  I'm not sure whether this is normal or abnormal:

--- SIGCHLD (Child exited) ---
wait4(-1, [WIFSTOPPED(s) && WSTOPSIG(s) == SIGTRAP], WUNTRACED, NULL) =
6083
gettimeofday({961299583, 134497}, NULL) = 0
ptrace(PTRACE_PEEKUSER, 6083, 4*EIP, [0x4005b1b4]) = 0
ptrace(PTRACE_???, 6083, 0, 0x50fe827c) = 0
ptrace(PTRACE_???, 6083, 0, 0x50fe82c0) = 0
ptrace(PTRACE_POKEUSER, 6083, 4*ORIG_EAX, 0x14) = 0
ptrace(PTRACE_CONT, 6083, 0, SIG_0)     = 0
--- SIGCHLD (Child exited) ---
wait4(-1, [WIFSTOPPED(s) && WSTOPSIG(s) == SIGUSR1], WUNTRACED, NULL) =
6083
gettimeofday({961299583, 139633}, NULL) = 0
ptrace(PTRACE_PEEKUSER, 6083, 4*EIP, [0x100a4541]) = 0
ptrace(PTRACE_???, 6083, 0, 0x50fe827c) = 0
ptrace(PTRACE_SYSCALL, 6083, 0, SIG_0)  = 0
--- SIGCHLD (Child exited) ---
wait4(-1, [WIFSTOPPED(s) && WSTOPSIG(s) == SIGTRAP], WUNTRACED, NULL) =
6083
gettimeofday({961299583, 142397}, NULL) = 0
ptrace(PTRACE_PEEKUSER, 6083, 4*EIP, [0x4005b1b4]) = 0
ptrace(PTRACE_???, 6083, 0, 0x50fe827c) = 0
ptrace(PTRACE_???, 6083, 0, 0x50fe82c0) = 0
ptrace(PTRACE_POKEUSER, 6083, 4*ORIG_EAX, 0x14) = 0
ptrace(PTRACE_CONT, 6083, 0, SIG_0)     = 0
--- SIGCHLD (Child exited) ---
(repeat, ad infinitum)

	By adding "init=/bin/ash" to the command line, I can get to a
command prompt.  Hey, we're getting somewhere, bit by bit.

> BTW, what is Tom's Root/boot?  Is there anything special about it?  Would it 
> make sense to add it to my downloads when it can boot uml?

	Toms Root/boot (available at ftp.toms.net) is a single floppy
Linux.  Tom Oehser <to...@to...> has done a marvelous job of packing an
entire recovery environment into a 1.7M floppy.  It's really indespensible
for emergencies.
	Ny using a libc5 environment and doing insane things to shrink the
binaries, he's succeded at getting a very functional Linux system on a
single floppy.

	I'd love to see it as one of the available root environments for
uml.  He does have a short copyright message and two urls that he'd like
included in any derivative works, but I suspect that's not too much of a
problem; they could be included in a short README.toms.
	Quite honestly, if the last few details can be worked out, the
availability of a 3.6M root filesystem is a nice plus for simple projects.  
While I'm all for full distributions and their features, a slim root_fs
should be useful in itself.

	I've attached a tar file of the current work.  I'll be traveling
for a few days, so if anybody feels like playing, feel free.  I'd love to
see what people find...

mkdir --parents /mnt/spare/mirrors/	#Or change workpath in the script
cd /mnt/spare/mirrors
tar -xzvf toms-uml.tar.gz
cd /mnt/spare/mirrors/toms-uml

	If you don't have wget on your system, you'll have to
manually download tomsrtbt-1.7.205.tar.gz from ftp.toms.net to
/mnt/spare/mirrors/toms-uml
	Copy/link the uml kernel into /mnt/spare/mirrors/toms-uml .

./mk_toms_root 1.7.205

	Cheers,
	- Bill

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(Courtesy of Andrej Todosic <ato...@ub...>)
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William Stearns (wst...@po...).  Mason, Buildkernel, named2hosts, 
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