From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: [patch 1/2] genirq: Run irq handlers with interrupts disabled Date: Sat, 3 Apr 2010 06:45:20 +0200 Message-ID: <20100403044520.GA30558@elf.ucw.cz> References: <20100326000325.917127328@linutronix.de> <20100326000405.758579387@linutronix.de> <20100326061310.GV20695@one.firstfloor.org> <20100330053325.GL20695@one.firstfloor.org> <20100402093132.GA1360@ucw.cz> <20100402210916.GA23339@elf.ucw.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Thomas Gleixner Cc: Andi Kleen , Linus Torvalds , LKML , linux-arch@vger.kernel.org, Andrew Morton , Ingo Molnar , Peter Zijlstra , Alan Cox , David Miller , Greg Kroah-Hartman , Arnaldo Carvalho de Melo List-Id: linux-arch.vger.kernel.org On Sat 2010-04-03 00:51:20, Thomas Gleixner wrote: > Pavel, > > On Fri, 2 Apr 2010, Pavel Machek wrote: > > > On Fri 2010-04-02 22:42:51, Thomas Gleixner wrote: > > > On Fri, 2 Apr 2010, Pavel Machek wrote: > > > > > > > On Wed 2010-03-31 13:16:37, Thomas Gleixner wrote: > > > > > On Tue, 30 Mar 2010, Andi Kleen wrote: > > > > > > > > > > > > Why not simply force IRQF_DISABLED for all MSI interrupts. That still > > > > > > > allows nesting for non MSI ones, but it limits the chance of throwing > > > > > > > up reasonably well. That's a two liner. > > > > > > > > > > > > > > Can you please test whether it resolves the issue at hand ? > > > > > > > > > > > > Sorry for the late answer. Got confirmation that this patch > > > > > > fixes the test case. Thanks. > > > > > > > > > > Ok, I'll push it linus wards and cc stable. I think thats the least > > > > > intrusive safe bet we can have right now. > > > > > > > > stable? I'd say thats way too intrusive for -stable... > > > > > > So we better let the possible stack overruns unaddressed ? > > > > -stable should have no regressions, first and foremost. And this is > > pretty certain to introduce some, at least on low-powered system with > > serial ports. > > I think you misunderstood what I'm going to push. The patch merily > forces IRQF_DISABLED for MSI(X) based interrupts. So that does not > affect low powered systems in any way. > > It only affects high end systems where Dave Miller already said he did > the IRQF_DISABLED magic already in some NIC drivers just to prevent > that. Oops, yes, I did; lost in all the mails. > So I think your fear of regressions for low-powered systems is > completely unsubstantiated. Yep. Sorry for the noise. -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ksp.mff.cuni.cz ([195.113.26.206]:57367 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750883Ab0DCEp3 (ORCPT ); Sat, 3 Apr 2010 00:45:29 -0400 Date: Sat, 3 Apr 2010 06:45:20 +0200 From: Pavel Machek Subject: Re: [patch 1/2] genirq: Run irq handlers with interrupts disabled Message-ID: <20100403044520.GA30558@elf.ucw.cz> References: <20100326000325.917127328@linutronix.de> <20100326000405.758579387@linutronix.de> <20100326061310.GV20695@one.firstfloor.org> <20100330053325.GL20695@one.firstfloor.org> <20100402093132.GA1360@ucw.cz> <20100402210916.GA23339@elf.ucw.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-arch-owner@vger.kernel.org List-ID: To: Thomas Gleixner Cc: Andi Kleen , Linus Torvalds , LKML , linux-arch@vger.kernel.org, Andrew Morton , Ingo Molnar , Peter Zijlstra , Alan Cox , David Miller , Greg Kroah-Hartman , Arnaldo Carvalho de Melo Message-ID: <20100403044520.78MvxDI3DfqjVHCa3Z_hE137hYS9Fq3dfAJWMcvC1X4@z> On Sat 2010-04-03 00:51:20, Thomas Gleixner wrote: > Pavel, > > On Fri, 2 Apr 2010, Pavel Machek wrote: > > > On Fri 2010-04-02 22:42:51, Thomas Gleixner wrote: > > > On Fri, 2 Apr 2010, Pavel Machek wrote: > > > > > > > On Wed 2010-03-31 13:16:37, Thomas Gleixner wrote: > > > > > On Tue, 30 Mar 2010, Andi Kleen wrote: > > > > > > > > > > > > Why not simply force IRQF_DISABLED for all MSI interrupts. That still > > > > > > > allows nesting for non MSI ones, but it limits the chance of throwing > > > > > > > up reasonably well. That's a two liner. > > > > > > > > > > > > > > Can you please test whether it resolves the issue at hand ? > > > > > > > > > > > > Sorry for the late answer. Got confirmation that this patch > > > > > > fixes the test case. Thanks. > > > > > > > > > > Ok, I'll push it linus wards and cc stable. I think thats the least > > > > > intrusive safe bet we can have right now. > > > > > > > > stable? I'd say thats way too intrusive for -stable... > > > > > > So we better let the possible stack overruns unaddressed ? > > > > -stable should have no regressions, first and foremost. And this is > > pretty certain to introduce some, at least on low-powered system with > > serial ports. > > I think you misunderstood what I'm going to push. The patch merily > forces IRQF_DISABLED for MSI(X) based interrupts. So that does not > affect low powered systems in any way. > > It only affects high end systems where Dave Miller already said he did > the IRQF_DISABLED magic already in some NIC drivers just to prevent > that. Oops, yes, I did; lost in all the mails. > So I think your fear of regressions for low-powered systems is > completely unsubstantiated. Yep. Sorry for the noise. -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html