Re: [rtc-linux] [PATCH] rtc: remove BKL for ioctl()

[Alessandro Zummo <alessandro.zummo@towertech.it>]

On Sun, 22 Jun 2008 19:55:42 -0700
David Brownell <david-b@pacbell.net> wrote:

> Remove implicit use of BKL in ioctl() from the RTC framework.
> 
> Instead, the rtc->ops_lock is used.  That's the same lock that already
> protects the RTC operations when they're issued through the exported
> rtc_*() calls in drivers/rtc/interface.c ... making this a bugfix, not
> just a cleanup, since both ioctl calls and set_alarm() need to update
> IRQ enable flags and that implies a common lock (which RTC drivers as
> a rule do not provide on their own).
> 
> A new comment at the declaration of "struct rtc_class_ops" summarizes
> current locking rules.  It's not clear to me that the exceptions listed
> there should exist ... if not, those are pre-existing problems which can
> be fixed in a patch that doesn't relate to BKL removal.
> 
> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>


 Acked-by: Alessandro Zummo <a.zummo@towertech.it>

-- 

 Best regards,

 Alessandro Zummo,
  Tower Technologies - Torino, Italy

  http://www.towertech.it