Re: WARNING: at drivers/tty/tty_buffer.c:476 flush_to_ldisc()

Re: WARNING: at drivers/tty/tty_buffer.c:476 flush_to_ldisc()

[Sedat Dilek]

Hi Dave,

I suspected after initial testing a problem in TTY and applied two patches.
After more testing the root cause was a problem in JBD2.
A patch from Eric helped!
Follow the thread in [1] for more details.

If you are on Linux-Next (next-20130118) you need the following three patches.

Ilya Zykov (2):
      tty: Correct tty buffer flush.
      tty: Add driver unthrottle in ioctl(...,TCFLSH,..).

Eric Sandeen (1):
      jbd2: don't wake kjournald unnecessarily

Hope this helps you.

Regards,
- Sedat -

[0] http://marc.info/?t=135862023700004&r=1&w=2
[1] http://marc.info/?l=linux-serial&m=135860500714909&w=2
[2] http://git.kernel.org/?p=linux/kernel/git/gregkh/tty.git;a=commitdiff;h=a1bf9584429d61b7096f93ae09325e1ba538e9e8
[3] http://patchwork.ozlabs.org/patch/207237/

Re: WARNING: at drivers/tty/tty_buffer.c:476 flush_to_ldisc()

[Eric Sandeen]

On 1/19/13 4:44 PM, Sedat Dilek wrote:
> Hi Dave,
> 
> I suspected after initial testing a problem in TTY and applied two patches.
> After more testing the root cause was a problem in JBD2.
> A patch from Eric helped!

oh, excellent ;)

Helped what, exactly?

> Follow the thread in [1] for more details.
> 
> If you are on Linux-Next (next-20130118) you need the following three patches.
> 
> Ilya Zykov (2):
>       tty: Correct tty buffer flush.
>       tty: Add driver unthrottle in ioctl(...,TCFLSH,..).
> 
> Eric Sandeen (1):
>       jbd2: don't wake kjournald unnecessarily

Hum, I would not have expected this to *matter*, I thought it was just a perf
optimization.  Hm.  What do you think it fixed, exactly?

(sorry, have not followed that thread, busy elsewhere ATM)

-eric

> Hope this helps you.
> 
> Regards,
> - Sedat -
> 
> [0] http://marc.info/?t=135862023700004&r=1&w=2
> [1] http://marc.info/?l=linux-serial&m=135860500714909&w=2
> [2] http://git.kernel.org/?p=linux/kernel/git/gregkh/tty.git;a=commitdiff;h=a1bf9584429d61b7096f93ae09325e1ba538e9e8
> [3] http://patchwork.ozlabs.org/patch/207237/
> 

Re: WARNING: at drivers/tty/tty_buffer.c:476 flush_to_ldisc()

[Sedat Dilek]

On Sat, Jan 19, 2013 at 11:51 PM, Eric Sandeen <sandeen@redhat.com> wrote:
> On 1/19/13 4:44 PM, Sedat Dilek wrote:
>> Hi Dave,
>>
>> I suspected after initial testing a problem in TTY and applied two patches.
>> After more testing the root cause was a problem in JBD2.
>> A patch from Eric helped!
>
> oh, excellent ;)
>
> Helped what, exactly?
>

Fixed a call-trace which I could reproduce running pm_test/freezer
(see [1] "[C.1] TRY TO FORCE THE CALL-TRACE").

- Sedat -

[1] http://marc.info/?l=linux-kernel&m=135862010419101&w=2

>>
 Follow the thread in [1] for more details.
>>
>> If you are on Linux-Next (next-20130118) you need the following three patches.
>>
>> Ilya Zykov (2):
>>       tty: Correct tty buffer flush.
>>       tty: Add driver unthrottle in ioctl(...,TCFLSH,..).
>>
>> Eric Sandeen (1):
>>       jbd2: don't wake kjournald unnecessarily
>
> Hum, I would not have expected this to *matter*, I thought it was just a perf
> optimization.  Hm.  What do you think it fixed, exactly?
>
> (sorry, have not followed that thread, busy elsewhere ATM)
>
> -eric
>
>> Hope this helps you.
>>
>> Regards,
>> - Sedat -
>>
>> [0] http://marc.info/?t=135862023700004&r=1&w=2
>> [1] http://marc.info/?l=linux-serial&m=135860500714909&w=2
>> [2] http://git.kernel.org/?p=linux/kernel/git/gregkh/tty.git;a=commitdiff;h=a1bf9584429d61b7096f93ae09325e1ba538e9e8
>> [3] http://patchwork.ozlabs.org/patch/207237/
>>
>

Re: WARNING: at drivers/tty/tty_buffer.c:476 flush_to_ldisc()

[Sedat Dilek]

On Sat, Jan 19, 2013 at 11:44 PM, Sedat Dilek <sedat.dilek@gmail.com> wrote:
> Hi Dave,
>
> I suspected after initial testing a problem in TTY and applied two patches.
> After more testing the root cause was a problem in JBD2.
> A patch from Eric helped!
> Follow the thread in [1] for more details.
>
> If you are on Linux-Next (next-20130118) you need the following three patches.
>
> Ilya Zykov (2):
>       tty: Correct tty buffer flush.
>       tty: Add driver unthrottle in ioctl(...,TCFLSH,..).
>
> Eric Sandeen (1):
>       jbd2: don't wake kjournald unnecessarily
>
> Hope this helps you.
>
> Regards,
> - Sedat -
>
> [0] http://marc.info/?t=135862023700004&r=1&w=2
> [1] http://marc.info/?l=linux-serial&m=135860500714909&w=2
> [2] http://git.kernel.org/?p=linux/kernel/git/gregkh/tty.git;a=commitdiff;h=a1bf9584429d61b7096f93ae09325e1ba538e9e8
> [3] http://patchwork.ozlabs.org/patch/207237/

I am awfully sorry to tell you that my (JBD2) problem still exist!
Not sure this is anymore related to TTY-NEXT, so better I shut up!

- Sedat -

[1] http://marc.info/?l=linux-kernel&m=135864041624404&w=2