Not getting login prompt after CPU entered into cpu_idle() state

Not getting login prompt after CPU entered into cpu_idle() state

[Srinidhi M]

Hi All,

We have ported the kernel from 2.6.10 version to 2.6.32 kernel version
for our Phytec LPC-3180 board. We have done good work and able to
complete the kernel part i.e. completed the start_kernel function and
CPU entered into IDLE state from cpu_idle() function which is defined
in rest_init() function in main.c file. However, rest_init() function
also creates TWO threads. One thread is for running the kernel_init()
function where it calls the init_post() function. In this, after a few
other calls, there is a call to init the init-process i.e.
run_init_process("/sbin/init"). After this, we are not seeing neither
any errors nor login prompt in hyper terminal. We end up without
getting any login prompt. Any idea would be greatly help us in getting
the login prompt / for debugging the sources further for identifying
the exact reason / location to find out the error.

Here are the final debug statements which we are seeing in the hyper terminal.

<6>VFP support v0.3: implementor 41 architecture 1 part 10 variant 9 rev 1
<5>RAMDISK: gzip image found at block 0
VFS: Mounted root (ext2 filesystem) on device 1:0.
<6>Freeing init memory: 80K
.....@ <init/main.c>  <init_post>  <900>
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <271> ret = 0 : /sbin/init
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <274>
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <271> ret = 0 :
/sbin/modprobe
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <274>
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <271> ret = 0 :
/sbin/modprobe
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <274>
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <271> ret = 0 :
/sbin/modprobe
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <274>
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <271> ret = 0 :
/sbin/modprobe
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <274>

If we load 2.6.10 kernel image, we are getting login prompt in the
hyper terminal on the same Phytec board.

NOTE: We are using the same file system on 2.6.32 kernel which was
running fine on 2.6.10 kernel.

We will provide if any one need additional information / complete log.

Thanks in advance.

Regards,
Srinidhi.

Not getting login prompt after CPU entered into cpu_idle() state

[Mulyadi Santosa]

Hi...

On Thu, Jul 5, 2012 at 12:12 PM, Srinidhi M <srinidhi.m26@gmail.com> wrote:
> .....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <271> ret = 0 : /sbin/init

FYI I absolutely has no hands on experience on this kind of hack, so
this is purely speculation.

I am thinking, ret=0 when calling /sbin/init? AFAIK, a successful
open() operation should return something bigger than 0 as the file
descriptor.

Also, init should call /sbin/login or something similar. maybe
something is wrong when reading /etc/fstab or anything similar for
your kernel?



-- 
regards,

Mulyadi Santosa
Freelance Linux trainer and consultant

blog: the-hydra.blogspot.com
training: mulyaditraining.blogspot.com

Not getting login prompt after CPU entered into cpu_idle() state

[Jonathan Neuschäfer]

On Fri, Jul 06, 2012 at 12:56:45AM +0700, Mulyadi Santosa wrote:
> Hi...
> 
> On Thu, Jul 5, 2012 at 12:12 PM, Srinidhi M <srinidhi.m26@gmail.com> wrote:
> > .....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <271> ret = 0 : /sbin/init
> 
> FYI I absolutely has no hands on experience on this kind of hack, so
> this is purely speculation.
> 
> I am thinking, ret=0 when calling /sbin/init? AFAIK, a successful
> open() operation should return something bigger than 0 as the file
> descriptor.

Only if 0 is already in use.

But isn't that exec and not open?


Thanks,
Jonathan

Not getting login prompt after CPU entered into cpu_idle() state

[Mulyadi Santosa]

On Fri, Jul 6, 2012 at 1:02 AM, Jonathan Neusch?fer
<j.neuschaefer@gmx.net> wrote:
> On Fri, Jul 06, 2012 at 12:56:45AM +0700, Mulyadi Santosa wrote:
> Only if 0 is already in use.
>
> But isn't that exec and not open?

hm, right, it's exec....so it should be just launch the init with
return value as programmed ( 0?)

-- 
regards,

Mulyadi Santosa
Freelance Linux trainer and consultant

blog: the-hydra.blogspot.com
training: mulyaditraining.blogspot.com

Not getting login prompt after CPU entered into cpu_idle() state

[sk.syed2]

> Here are the final debug statements which we are seeing in the hyper terminal.

Can you post the full logs WITHOUT your debug prints. What is the
toolchain you are using?

> If we load 2.6.10 kernel image, we are getting login prompt in the
> hyper terminal on the same Phytec board.

You can isolate the problem by writing a small utility(blinky) which
would blink some LED on the board and then pass (init = /sbin/blinky)
it in your kernel command line.

Not getting login prompt after CPU entered into cpu_idle() state

[Srinidhi M]

On Fri, Jul 6, 2012 at 1:10 AM, sk.syed2 <sk.syed2@gmail.com> wrote:
>> Here are the final debug statements which we are seeing in the hyper terminal.
>
> Can you post the full logs WITHOUT your debug prints. What is the
> toolchain you are using?

Please find the attached FULL log file without our own messages.

>> If we load 2.6.10 kernel image, we are getting login prompt in the
>> hyper terminal on the same Phytec board.
>
> You can isolate the problem by writing a small utility(blinky) which
> would blink some LED on the board and then pass (init = /sbin/blinky)
> it in your kernel command line.

We are assuming that the kernel is completely booted, in 2.6.32
kernel, without any issues as it entered into cpu_idle state. We are
guessing that there is an error in the file system sources (i.e.
sbin/init). Unfortunately, we do not have the sources for the
available file system and we have downloaded the file system from the
following Phytec link.

http://www.phytec.com/products/linux/bsp-LPC3180.html

Please provide some insight to find out the reason for not getting login prompt.

Thanks and Regards,
Srinidhi M.

> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
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Not getting login prompt after CPU entered into cpu_idle() state

[Philipp Ittershagen]

On Fri, Jul 6, 2012 at 10:39 AM, Srinidhi M <srinidhi.m26@gmail.com> wrote:
> On Fri, Jul 6, 2012 at 1:10 AM, sk.syed2 <sk.syed2@gmail.com> wrote:
>>> Here are the final debug statements which we are seeing in the hyper terminal.
>>
>> Can you post the full logs WITHOUT your debug prints. What is the
>> toolchain you are using?
>
> Please find the attached FULL log file without our own messages.
>

If the init process cannot be started, the kernel should at least
panic. Try passing init=/foo to the kernel boot to force the panic. If
that does not lead to the panic, then yuo can be sure that it is a
kernel problem.


Greetings,

  Philipp

Not getting login prompt after CPU entered into cpu_idle() state

[sk.syed2]

> We are assuming that the kernel is completely booted, in 2.6.32
> kernel, without any issues as it entered into cpu_idle state. We are
> guessing that there is an error in the file system sources (i.e.
> sbin/init). Unfortunately, we do not have the sources for the
> available file system and we have downloaded the file system from the
> following Phytec link.

It seems to me that the kernel and filesystem are not built with the same
toolchain version. This could be a problem. You can use buildroot
http://buildroot.uclibc.org/download.html  to generate a new filesystem.

-syed

Not getting login prompt after CPU entered into cpu_idle() state

[Srinidhi M]

On Sat, Jul 7, 2012 at 4:53 AM, sk.syed2 <sk.syed2@gmail.com> wrote:
>> We are assuming that the kernel is completely booted, in 2.6.32
>> kernel, without any issues as it entered into cpu_idle state. We are
>> guessing that there is an error in the file system sources (i.e.
>> sbin/init). Unfortunately, we do not have the sources for the
>> available file system and we have downloaded the file system from the
>> following Phytec link.
>
> It seems to me that the kernel and filesystem are not built with the same
> toolchain version. This could be a problem. You can use buildroot
> http://buildroot.uclibc.org/download.html  to generate a new filesystem.

Thanks for your information. Yes. As you said we used the file system
that was build by Phytec for 2.6.10 kernel version. However, we do not
have the file system sources with us.

So, we have built busybox with the same tool chain version that we
used to build the 2.6.32 kernel image. Even though, we are seeing the
same error messages i.e. we are seeing 5 to 6 "/sbin/modprobe" calls
after calling the "/sbin/init". After that, we did not see any
messages at all. We are getting the SAME log messages that we got
earlier when we use this busybox file system which was build with same
tool chain.

Please let us know, if we are doing anything wrong here, still.

Thanks and Regards,
Srinidhi M.

> -syed
>
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies

Not getting login prompt after CPU entered into cpu_idle() state

[Philipp Ittershagen]

On Mon, Jul 9, 2012 at 3:36 PM, Srinidhi M <srinidhi.m26@gmail.com> wrote:
> So, we have built busybox with the same tool chain version that we
> used to build the 2.6.32 kernel image. Even though, we are seeing the
> same error messages i.e. we are seeing 5 to 6 "/sbin/modprobe" calls
> after calling the "/sbin/init". After that, we did not see any
> messages at all. We are getting the SAME log messages that we got
> earlier when we use this busybox file system which was build with same
> tool chain.

My next guess would be that some tty device nodes changed and your
init configuration at /etc/inittab points to wrong console devices. At
least that was the case when I had a similar error. Init starts and
puts the login prompt on the wrong console device so you don't see it.


Greetings,

  Philipp

Not getting login prompt after CPU entered into cpu_idle() state

[Srinidhi M]

Hi All,

We have ported the kernel from 2.6.10 version to 2.6.32 kernel version
for our Phytec LPC-3180 board. We have done good work and able to
complete the kernel part i.e. completed the start_kernel function and
CPU entered into IDLE state from cpu_idle() function which is defined
in rest_init() function in main.c file. However, rest_init() function
also creates TWO threads. One thread is for running the kernel_init()
function where it calls the init_post() function. In this, after a few
other calls, there is a call to init the init-process i.e.
run_init_process("/sbin/init"). After this, we are not seeing neither
any errors nor login prompt in hyper terminal. We end up without
getting any login prompt. Any idea would be greatly help us in getting
the login prompt / for debugging the sources further for identifying
the exact reason / location to find out the error.

Here are the final debug statements which we are seeing in the hyper terminal.

<6>VFP support v0.3: implementor 41 architecture 1 part 10 variant 9 rev 1
<5>RAMDISK: gzip image found at block 0
VFS: Mounted root (ext2 filesystem) on device 1:0.
<6>Freeing init memory: 80K
.....@ <init/main.c>  <init_post>  <900>
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <271> ret = 0 : /sbin/init
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <274>
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <271> ret = 0 :
/sbin/modprobe
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <274>
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <271> ret = 0 :
/sbin/modprobe
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <274>
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <271> ret = 0 :
/sbin/modprobe
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <274>
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <271> ret = 0 :
/sbin/modprobe
.....@ <arch/arm/kernel/sys_arm.c>  <kernel_execve>  <274>

If we load 2.6.10 kernel image, we are getting login prompt in the
hyper terminal on the same Phytec board.

NOTE: We are using the same file system on 2.6.32 kernel which was
running fine on 2.6.10 kernel.

We will provide if any one need additional information / complete log.

Thanks in advance.

Regards,
Srinidhi.