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From: Arnd Bergmann <arnd@arndb.de>
To: Alan Cox <alan@linux.intel.com>
Subject: Re: [PATCH 04/14] vc: Locking clean up
Date: Fri, 30 Apr 2010 22:30:22 +0200
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On Thursday 01 April 2010 18:04:59 Alan Cox wrote:
> @@ -282,7 +282,12 @@ static inline unsigned short *screenpos(struct vc_data *vc, int offset, int view
>  
>  static inline void scrolldelta(int lines)
>  {
> +       lock_kernel();
> +       /* FIXME */
> +       /* scrolldelta needs some kind of consistency lock, but the BKL was
> +          and still is not protecting versus the scheduled back end */
>         scrollback_delta += lines;
> +       unlock_kernel();
>         schedule_console_callback();
>  }
>  

This one triggered a might_sleep() warning in _lock_kernel(), because
it's called from the keyboard interrupt.

	Arnd