From: Andrew Bird <ajb@spheresystems.co.uk>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Subject: Re: Spinlock debugging
Date: Mon, 11 Sep 2006 17:38:21 +0100
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Alan
	Yes, I have low_latency set for kernels lower than 2.6.17. I'm currently 
testing using 2.6.15. When you mention 'write method for flow control' do you 
mean for software XON/XOFF etc?
	On a more generic note, is the spinlock debug output read as a stack and what 
do the '=======' line breaks signify, looping?

Thanks


Andrew

On Monday 11 September 2006 17:36, Alan Cox wrote:
> Ar Llu, 2006-09-11 am 16:32 +0100, ysgrifennodd Andrew Bird (Sphere
>
> Systems):
> > will be lost. But if I comment out the line that tells the tty layer that
> > it's implemented, I end up with a BUG - spinlock recursion. Can anybody
> > tell me how to interpret the output?
>
> Looks like your driver calls flush_to_ldisc with low latency set and
> then can't handle the flush_to_ldisc causing n_tty to call back into the
> write method for flow control.
>
> Alan
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