From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757439Ab0KKAqz (ORCPT ); Wed, 10 Nov 2010 19:46:55 -0500 Received: from ozlabs.org ([203.10.76.45]:59326 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757318Ab0KKAqx (ORCPT ); Wed, 10 Nov 2010 19:46:53 -0500 From: Rusty Russell To: Christoph Hellwig Subject: Re: [2.6.37-rc1, OOM] virtblk: OOM in do_virtblk_request() Date: Thu, 11 Nov 2010 11:16:48 +1030 User-Agent: KMail/1.13.5 (Linux/2.6.35-22-generic-pae; KDE/4.5.1; i686; ; ) Cc: Dave Chinner , mst@redhat.com, linux-kernel@vger.kernel.org References: <20101105013003.GE13830@dastard> <20101110133151.GB2101@infradead.org> In-Reply-To: <20101110133151.GB2101@infradead.org> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201011111116.48263.rusty@rustcorp.com.au> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 11 Nov 2010 12:01:51 am Christoph Hellwig wrote: > Rusty, Michael, > > any comments? I think Dave's observation is correct, and the lack of > a mempool for allocations in the virtio stack is a no-go for virtio_blk. Interesting. virtio will try to fall back to using direct ring entries if it can, but if course if your request is too large it can never do that. So, we could add a memory pool, or restrict the request size in virtio_blk. Any other thoughts? Rusty.