RE: printf internals
- From: "Siva Prasad" <sprasad@xxxxxxxxx>
- Date: Wed, 19 Dec 2007 15:31:15 -0800
Yes!... this is a embedded system, and will not have monitor. So, serial
is the default console.
I pass cmdline as "root=/dev/ram rw console=ttyS0,115200"
Thanks
Siva
-----Original Message-----
From: Scott Russell [mailto:catfather@xxxxxxxxxx]
Sent: Wednesday, December 19, 2007 3:31 PM
To: Siva Prasad
Cc: Clemens Koller; David Newall; linux-kernel@xxxxxxxxxxxxxxx
Subject: RE: printf internals
On Wed, 2007-12-19 at 14:33 -0800, Siva Prasad wrote:
Thank you very much for your response Clemens.as it uses the stdout (fd = 1) and write(1, ...) to it.
I tried strace on a regular system. It does not show which tty, etc.,
ramdisk. Kernel boots fine to a point where it starts accessing ramdisk
This is not a student project. I am trying to build my own kernel and
and executes init scripts. From there on nothing gets printed. I did
some debugging and found that prints of user land programs are not
coming to the serial console, while kernel prints are working fine. I
found all the programs getting executed, by placing a printk in execve
routine and printing the arguments.
and see why it is not printing messages from user program. I placed a
So, I wanted to trace down the path from user program to the kernel
printk in drivers/char/tty_io.c:tty_write() and it is not getting called
from my file system. I tried the same thing on my good system (say
regular PC) and it works as expected.
Any clues that can help debug this issue is highly appreciated.
How can I get access to the same printf string inside kernel.
This sounds like you're printing out the serial console instead.
--
Scott <catfather@xxxxxxxxxx>
AIM: BlueCame1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
- Follow-Ups:
- Re: printf internals
- From: Masoud Sharbiani \"مسعود شربیانی\"
- Re: printf internals
- References:
- printf internals
- From: Siva Prasad
- Re: printf internals
- From: David Newall
- Re: printf internals
- From: Clemens Koller
- RE: printf internals
- From: Siva Prasad
- RE: printf internals
- From: Scott Russell
- printf internals
- Prev by Date: Re: [patch 17/20] non-reclaimable mlocked pages
- Next by Date: Re: [PATCH 08/28] SECURITY: Allow kernel services to override LSM settings for task actions [try #2]
- Previous by thread: RE: printf internals
- Next by thread: Re: printf internals
- Index(es):
Relevant Pages
|
