public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
To: Ben Nizette <bn@niasdigital.com>
Cc: tglx@linutronix.de, David Brownell <david-b@pacbell.net>,
	hskinnemoen@atmel.com, kernel@avr32linux.org,
	linux-kernel@vger.kernel.org, imre.deak@nokia.com, mingo@elte.hu,
	Bill Gatliff <bgat@billgatliff.com>,
	Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Subject: Re: [PATCH] ads7846: fix unsafe disable_irq (was [REGRESSION] threaded interrupt handler support breaks (some) irq handling on AVR32)
Date: Wed, 15 Apr 2009 18:58:27 -0700	[thread overview]
Message-ID: <20090416015826.GA2413@dtor-d630.eng.vmware.com> (raw)
In-Reply-To: <1239842517.29831.47.camel@linux-51e8.site>

On Thu, Apr 16, 2009 at 10:41:57AM +1000, Ben Nizette wrote:
> On Wed, 2009-04-15 at 09:57 +0200, Haavard Skinnemoen wrote:
> > Shouldn't that be disable_irq_nosync()?
> 
> Indeed, good catch.  That fixes it.
> 
> --------------8<--------------------
> 
> The use of disable_irq inside the handler for the interrupt being
> disabled has always been dangerous.  disable_irq should wait for that
> handler to complete before returning -> deadlock.
> 
> For some reason this wasn't actually the case until 3aa551c9b was merged
> but since this time, the ads7846 driver has deadlocked the system on
> first interrupt.
> 
> Convert the driver to use the handler-safe _nosync variant.
> 

Applied, thank you very much Ben.

-- 
Dmitry

      reply	other threads:[~2009-04-16  1:58 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <1239685153.19815.12.camel@linux-51e8.site>
2009-04-14  8:37 ` [REGRESSION] threaded interrupt handler support breaks (some) irq handling on AVR32 Ben Nizette
2009-04-15  1:30   ` Ben Nizette
2009-04-15  7:57     ` Haavard Skinnemoen
2009-04-15  8:33       ` Haavard Skinnemoen
2009-04-15 16:01         ` Bill Gatliff
2009-04-16  8:40           ` Haavard Skinnemoen
2009-04-16 13:25             ` Bill Gatliff
2009-04-16  0:41       ` [PATCH] ads7846: fix unsafe disable_irq (was [REGRESSION] threaded interrupt handler support breaks (some) irq handling on AVR32) Ben Nizette
2009-04-16  1:58         ` Dmitry Torokhov [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20090416015826.GA2413@dtor-d630.eng.vmware.com \
    --to=dmitry.torokhov@gmail.com \
    --cc=bgat@billgatliff.com \
    --cc=bn@niasdigital.com \
    --cc=david-b@pacbell.net \
    --cc=haavard.skinnemoen@atmel.com \
    --cc=hskinnemoen@atmel.com \
    --cc=imre.deak@nokia.com \
    --cc=kernel@avr32linux.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=tglx@linutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox