Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754157Ab1C2TjP (ORCPT ); Tue, 29 Mar 2011 15:39:15 -0400 Received: from zene.cmpxchg.org ([85.214.230.12]:32877 "EHLO zene.cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751212Ab1C2TjN (ORCPT ); Tue, 29 Mar 2011 15:39:13 -0400 Date: Tue, 29 Mar 2011 21:39:07 +0200 From: Johannes Weiner To: "'Christoph Hellwig'" Cc: Sean Noonan , "'Michel Lespinasse'" , "'linux-kernel@vger.kernel.org'" , Martin Bligh , Trammell Hudson , Christos Zoulas , "'linux-xfs@oss.sgi.com'" , Stephen Degler , "'linux-mm@kvack.org'" Subject: Re: XFS memory allocation deadlock in 2.6.38 Message-ID: <20110329193907.GK2310@cmpxchg.org> References: <081DDE43F61F3D43929A181B477DCA95639B52FD@MSXAOA6.twosigma.com> <081DDE43F61F3D43929A181B477DCA95639B5327@MSXAOA6.twosigma.com> <20110324174311.GA31576@infradead.org> <081DDE43F61F3D43929A181B477DCA95639B5349@MSXAOA6.twosigma.com> <081DDE43F61F3D43929A181B477DCA95639B534E@MSXAOA6.twosigma.com> <081DDE43F61F3D43929A181B477DCA95639B5359@MSXAOA6.twosigma.com> <20110329192434.GA10536@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110329192434.GA10536@infradead.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1378 Lines: 34 On Tue, Mar 29, 2011 at 03:24:34PM -0400, 'Christoph Hellwig' wrote: > Can you check if the brute force patch below helps? If it does I > still need to refine it a bit, but it could be that we are doing > an allocation under an xfs lock that could recurse back into the > filesystem. We have a per-process flag to disable that for normal > kmalloc allocation, but we lost it for vmalloc in the commit you > bisected the regression to. > > > Index: xfs/fs/xfs/linux-2.6/kmem.h > =================================================================== > --- xfs.orig/fs/xfs/linux-2.6/kmem.h 2011-03-29 21:16:58.039224236 +0200 > +++ xfs/fs/xfs/linux-2.6/kmem.h 2011-03-29 21:17:08.368223598 +0200 > @@ -63,7 +63,7 @@ static inline void *kmem_zalloc_large(si > { > void *ptr; > > - ptr = vmalloc(size); > + ptr = __vmalloc(size, GFP_NOFS | __GFP_HIGHMEM, PAGE_KERNEL); > if (ptr) > memset(ptr, 0, size); > return ptr; Note that vmalloc is currently broken in that it does a GFP_KERNEL allocation if it has to allocate page table pages, even when invoked with GFP_NOFS: http://marc.info/?l=linux-mm&m=128942194520631&w=4 -- 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/