Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-ie0-f177.google.com ([209.85.223.177]:48656 "EHLO mail-ie0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754481AbaIZO3e (ORCPT ); Fri, 26 Sep 2014 10:29:34 -0400 Received: by mail-ie0-f177.google.com with SMTP id x19so15656199ier.22 for ; Fri, 26 Sep 2014 07:29:34 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <1411740170-18611-2-git-send-email-hch@lst.de> References: <1411740170-18611-1-git-send-email-hch@lst.de> <1411740170-18611-2-git-send-email-hch@lst.de> Date: Fri, 26 Sep 2014 10:29:34 -0400 Message-ID: Subject: Re: [PATCH] pnfs/blocklayout: serialize GETDEVICEINFO calls From: Trond Myklebust To: Christoph Hellwig Cc: Linux NFS Mailing List Content-Type: text/plain; charset=UTF-8 Sender: linux-nfs-owner@vger.kernel.org List-ID: On Fri, Sep 26, 2014 at 10:02 AM, Christoph Hellwig wrote: > The rpc_pipefs code isn't thread safe, leading to occasional use after > frees when running xfstests generic/241 (dbench). > > Signed-off-by: Christoph Hellwig > --- > fs/nfs/blocklayout/rpc_pipefs.c | 14 +++++++++----- > fs/nfs/netns.h | 1 + > 2 files changed, 10 insertions(+), 5 deletions(-) > > It worries me that we're putting a mutex directly in the writeback path. For small arrays, it might be acceptable, but what if you have a block device with 1000s of disks on the back end? Is there no better way to fix this issue? -- Trond Myklebust Linux NFS client maintainer, PrimaryData trond.myklebust@primarydata.com