linux-kernel - Re: WARN_ON_ONCE(in_nmi()) hit in irq_work_queue

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] [day] [month] [year] [list]

Message-ID: <20140807131840.GC19662@localhost.localdomain>
Date:	Thu, 7 Aug 2014 15:18:42 +0200
From:	Frederic Weisbecker <fweisbec@...il.com>
To:	Peter Zijlstra <peterz@...radead.org>
Cc:	Dave Jones <davej@...hat.com>,
	Linux Kernel <linux-kernel@...r.kernel.org>
Subject: Re: WARN_ON_ONCE(in_nmi()) hit in irq_work_queue_on

On Thu, Aug 07, 2014 at 03:15:36PM +0200, Peter Zijlstra wrote:
> On Thu, Aug 07, 2014 at 02:58:55PM +0200, Frederic Weisbecker wrote:
> > On Thu, Aug 07, 2014 at 10:13:21AM +0200, Peter Zijlstra wrote:
> > > On Thu, Aug 07, 2014 at 01:44:58AM +0200, Frederic Weisbecker wrote:
> > > > In fact the problem has arised since the recent irq work patches I did.
> > > 
> > > No, those just added the WARN, previously we send the resched IPI, and
> > > that's equally wrong from NMI context.
> > 
> > Well the scheduler IPI was rather used for remote kicks before we had remote irq
> > work. This includes local kicks as well as the caller could need to kick
> > anywhere. As in inc_nr_running().
> > 
> > But for strict local kicks, as in perf, we were using tick_nohz_full_kick() which has
> > been using irq work for a while. But it got broken when we replaced it to call irq_work_queue_on
> > instead of irq_work_queue.
> 
> OK, clearly I made a mess of things in my head ;-)

I'm a bit responsible for that mess since I created quite some flavours of nohz kicks
all around :)

But now they should be more unified.
--
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/