From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752866Ab3KSUPf (ORCPT ); Tue, 19 Nov 2013 15:15:35 -0500 Received: from merlin.infradead.org ([205.233.59.134]:48251 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752069Ab3KSUPd (ORCPT ); Tue, 19 Nov 2013 15:15:33 -0500 Date: Tue, 19 Nov 2013 13:15:31 -0700 From: Jens Axboe To: Dave Chinner Cc: linux-kernel@vger.kernel.org Subject: Re: [Regression x2, 3.13-git] virtio block mq hang, iostat busted on virtio devices Message-ID: <20131119201531.GA4094@kernel.dk> References: <20131119080218.GJ11434@dastard> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20131119080218.GJ11434@dastard> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 19 2013, Dave Chinner wrote: > Hi Jens, > > I was just running xfstests on a 3.13 kernel that has had the block > layer changed merged into it. generic/269 on XFS is hanging on a 2 > CPU VM using virtio,cache=none for the block devices under test, > with many (130+) threads stuck below submit_bio() like this: > > Call Trace: > [] schedule+0x29/0x70 > [] percpu_ida_alloc+0x16e/0x330 > [] blk_mq_wait_for_tags+0x1f/0x40 > [] blk_mq_alloc_request_pinned+0x4e/0xf0 > [] blk_mq_make_request+0x3bb/0x4a0 > [] generic_make_request+0xc2/0x110 > [] submit_bio+0x6c/0x120 > > reads and writes are hung, both data (direct and buffered) and > metadata. > > Some IOs are sitting in io_schedule, waiting for IO completion (both > buffered and direct IO, both reads and writes) so it looks like IO > completion has stalled in some manner, too. Can I get a recipe to reproduce this? I haven't had any luck so far. -- Jens Axboe