linux-kernel - Re: [rtc-linux] Re: [PATCH] rtc: Make rtc_update

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20090423184024.39402a8f@i1501.lan.towertech.it>
Date:	Thu, 23 Apr 2009 18:40:24 +0200
From:	Alessandro Zummo <alessandro.zummo@...ertech.it>
To:	rtc-linux@...glegroups.com
Cc:	vapier.adi@...il.com, Atsushi Nemoto <anemo@....ocn.ne.jp>,
	akpm@...ux-foundation.org, linux-kernel@...r.kernel.org,
	hcegtvedt@...el.com, vapier@...too.org, rongkai.zhan@...driver.com,
	balajirrao@...nmoko.org, david-b@...bell.net,
	broonie@...nsource.wolfsonmicro.com
Subject: Re: [rtc-linux] Re: [PATCH] rtc: Make rtc_update_irq callable with
  irqs enabled

On Thu, 23 Apr 2009 12:30:58 -0400
Mike Frysinger <vapier.adi@...il.com> wrote:

>   for the blackfin you should just check if
> >  you have locking issues in your irq routine  
> 
> the Blackfin driver calls rtc_update_irq() from its IRQ handler and
> the handler is not registered with IRQF_DISABLED.  it makes more sense
> to me to fix rtc_update_irq() than require all RTC drivers to register
> with IRQF_DISABLED.  especially in my case as the Blackfin driver
> itself doesnt need any locks.

 I agree. rtc_update_irq is not problematic by itself, it just takes
 locks that other parts of the driver should take appropriately.

 For example, if you take irq_lock with irqs enabled you
 will get in trouble. blackfin seems ok, for the other
 drivers we need to verify this.

-- 

 Best regards,

 Alessandro Zummo,
  Tower Technologies - Torino, Italy

  http://www.towertech.it

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/