User-mode Linux kernel port

I'm having issues with UML.

I've got a rootfs that used to work with an older UML.  With 2.4.24, I 
try and boot with the following arguments:

./linux-2.4.24  mem=256M con0=fd:0,fd:1 con=pts ubd0=test,rootfs debug 
msp_view=build_neptune_2.0_int11

The msp_view thing causes additional mounts to be created at init time. 
  However, I get a bunch of errors in my console window when I try to 
log in:

ed Hat Linux release 8.0 (Psyche)
Plankton/CELP 2.5.0 - Kernel 2.4.24-1um on an i686

(none) login: Registering fd 47 twice
Irqs : 3, 3
Ids : 0xa022c3f8, 0xa022c3f8
Registering fd 47 twice
Irqs : 3, 3
Ids : 0xa022c3f8, 0xa022c3f8



If I then keep going, I end up with a whole bunch of lines like:

Failed to forward -1359446016 to pid 16452, err = 9


As part of my efforts to try and debug this, I wanted to dump out the 
names of the processes that were calling os_set_owner().  Accordingly in 
  um/os/file.c I included <linux/sched.c> and wrote some code with 
appropriate locking around the tasklist_lock so that I could match the 
pid against the process name.

When I compiled, it grabbed the sched.h from /usr/include rather than 
from the kernel build, and everything blew up.

So I guess I'm asking for help on two fronts.  1) How do I fix the build 
process to pick up the kernel includes (and why doesn't it do that by 
default?).  2) Any ideas why I'm getting the descriptor thing?

Thanks,

Chris

-- 
Chris Friesen                    | MailStop: 043/33/F10
Nortel Networks                  | work: (613) 765-0557
3500 Carling Avenue              | fax:  (613) 765-2986
Nepean, ON K2H 8E9 Canada        | email: cfriesen@...

Hi all,

>> Problem 1.) How do I shutdown a kernel thread when the uml goes
>> down? At the moment my patched kernle gets stuck with 100% CPU
>> usage when I trie to shut down the uml kernel.
Ok uml_exitcall fixed this problem.

>> Problem 2.) How can I make sure that my kernel thread I startet
>> after the networking stuff is inited? At the moment I start the
>> kernel thread with a __initcall and just do a sleep(30) in the
>> thread.
> I didn't know about late_initcall, but it sounds promising.
And it works too.


>> Problem 3.) I can only create sockets in the "anonymous" namespace.
>> The normal namespace gives me some error which I don't rememeber
>> right now but I could find out what th errorcode was.
Well bind is returning -2 which seams to be -ENOENT. Does somebody know why 
this happens?

>> I guess the "normal" namespace is PF_LOCAL.
>IIRC yes.
I use PF_UNIX in the code. But that should be the same as PF_LOCAL.

> There has been a lot of request for a such feature, so I would like
> if you can post it here or rather on uml-devel (especially to avoid
> anyone trying it without specific knowledge), even if it is not
> complete. So we could better help you. Also, state whether it is onto
> 2.4 or 2.6.
At the moment I am working on 2.6.0-test11


Thanks for your help,
Patrick "Petschge" Kilian

Hi=0A=0AThanks a lot for your mail. As I have missed to select the=0Aoption=
 realted to UBD device in Block device while compiling.=0ANow the problem i=
s get solved.=0A=0ARahul.=0A=0AOn Thu, 26 Feb 2004 M A Young wrote :=0A>On =
Thu, 26 Feb 2004, Rahul Deshmukh wrote:=0A>=0A> >I am facing the problem of=
 "Kernel panic: VFS: Unable to mount root fs" I=0A> >am not getting what is=
 the solution for the problem.As I have gone=0A> >through mailing as well g=
ot solution as to give root=3D/dev/ubd/0 . But=0A> >that thing is also not =
working.=0A>=0A>root=3D/dev/ubd/0 is for when you have devfs enabled. One o=
f /dev/ubd0=0A>/dev/ubda or 98:0 should work (assuming you do have a root i=
mage called=0A>root_fs).=0A>=0A> 	Michael Young=0A=0A=0A=0A=0AKnowledge spe=
aks, but wisdom listens.=0A=0A

Hi,

I was looking at the way timer works on UML and noticed that missed_ticks
is not actually used for anything. Is there a plan for it? If not, maybe
we should drop it.

Cheers,
-- Pete

diff -ur -X dontdiff linux-2.6.3-rc2-uml-1/arch/um/kernel/skas/trap_user.c linux-2.6.3-rc2-uml-1-t1/arch/um/kernel/skas/trap_user.c
--- linux-2.6.3-rc2-uml-1/arch/um/kernel/skas/trap_user.c	2004-02-15 21:26:30.000000000 -0800
+++ linux-2.6.3-rc2-uml-1-t1/arch/um/kernel/skas/trap_user.c	2004-02-29 18:48:11.000000000 -0800
@@ -35,8 +35,6 @@
 	errno = save_errno;
 }
 
-extern int missed_ticks[];
-
 void user_signal(int sig, union uml_pt_regs *regs)
 {
 	struct signal_info *info;
diff -ur -X dontdiff linux-2.6.3-rc2-uml-1/arch/um/kernel/time_kern.c linux-2.6.3-rc2-uml-1-t1/arch/um/kernel/time_kern.c
--- linux-2.6.3-rc2-uml-1/arch/um/kernel/time_kern.c	2004-02-15 21:26:31.000000000 -0800
+++ linux-2.6.3-rc2-uml-1-t1/arch/um/kernel/time_kern.c	2004-02-29 19:02:44.000000000 -0800
@@ -41,12 +41,6 @@
 /* Changed at early boot */
 int timer_irq_inited = 0;
 
-/* missed_ticks will be modified after kernel memory has been 
- * write-protected, so this puts it in a section which will be left 
- * write-enabled.
- */
-int __attribute__ ((__section__ (".unprotected"))) missed_ticks[NR_CPUS];
-
 static int first_tick;
 static unsigned long long prev_tsc;
 static long long delta;   		/* Deviation per interval */
diff -ur -X dontdiff linux-2.6.3-rc2-uml-1/arch/um/kernel/trap_user.c linux-2.6.3-rc2-uml-1-t1/arch/um/kernel/trap_user.c
--- linux-2.6.3-rc2-uml-1/arch/um/kernel/trap_user.c	2004-02-15 21:26:31.000000000 -0800
+++ linux-2.6.3-rc2-uml-1-t1/arch/um/kernel/trap_user.c	2004-02-29 19:02:28.000000000 -0800
@@ -102,12 +102,11 @@
 			 sig, &sc);
 }
 
-extern int timer_irq_inited, missed_ticks[];
+extern int timer_irq_inited;
 
 void alarm_handler(int sig, struct sigcontext sc)
 {
 	if(!timer_irq_inited) return;
-	missed_ticks[cpu()]++;
 
 	if(sig == SIGALRM)
 		switch_timers(0);