Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753847AbaGKOz0 (ORCPT ); Fri, 11 Jul 2014 10:55:26 -0400 Received: from kanga.kvack.org ([205.233.56.17]:37181 "EHLO kanga.kvack.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751923AbaGKOzZ (ORCPT ); Fri, 11 Jul 2014 10:55:25 -0400 Date: Fri, 11 Jul 2014 10:55:24 -0400 From: Benjamin LaHaise To: "Elliott, Robert (Server Storage)" Cc: Christoph Hellwig , Jeff Moyer , Jens Axboe , "dgilbert@interlog.com" , James Bottomley , Bart Van Assche , "linux-scsi@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: scsi-mq V2 Message-ID: <20140711145524.GB12478@kvack.org> References: <20140710062040.GB20146@infradead.org> <94D0CD8314A33A4D9D801C0FE68B402958B96E3B@G9W0745.americas.hpqcorp.net> <20140710160422.GA13728@infradead.org> <20140710161438.GA30792@infradead.org> <94D0CD8314A33A4D9D801C0FE68B402958B971BB@G9W0745.americas.hpqcorp.net> <94D0CD8314A33A4D9D801C0FE68B402958B9742E@G9W0745.americas.hpqcorp.net> <94D0CD8314A33A4D9D801C0FE68B402958B979E6@G9W0745.americas.hpqcorp.net> <20140711061441.GA29629@infradead.org> <94D0CD8314A33A4D9D801C0FE68B402958B98323@G9W0745.americas.hpqcorp.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <94D0CD8314A33A4D9D801C0FE68B402958B98323@G9W0745.americas.hpqcorp.net> User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 11, 2014 at 02:33:12PM +0000, Elliott, Robert (Server Storage) wrote: > That ran 9 total hours with no problem. > > Rather than revert in the bisect trees, I added just this single additional > patch to the no-rebase tree, and the problem appeared: Can you try the below totally untested patch instead? It looks like put_reqs_available() is not irq-safe. -ben -- "Thought is the essence of where you are now." diff --git a/fs/aio.c b/fs/aio.c index 955947e..4b97180 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -830,16 +830,20 @@ void exit_aio(struct mm_struct *mm) static void put_reqs_available(struct kioctx *ctx, unsigned nr) { struct kioctx_cpu *kcpu; + unsigned long flags; preempt_disable(); kcpu = this_cpu_ptr(ctx->cpu); + local_irq_save(flags); kcpu->reqs_available += nr; + while (kcpu->reqs_available >= ctx->req_batch * 2) { kcpu->reqs_available -= ctx->req_batch; atomic_add(ctx->req_batch, &ctx->reqs_available); } + local_irq_restore(flags); preempt_enable(); } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/