From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 02336C4332F for ; Tue, 22 Nov 2022 20:31:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234837AbiKVUa7 (ORCPT ); Tue, 22 Nov 2022 15:30:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37790 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234470AbiKVUav (ORCPT ); Tue, 22 Nov 2022 15:30:51 -0500 Received: from out2.migadu.com (out2.migadu.com [188.165.223.204]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1C64C2CE2D for ; Tue, 22 Nov 2022 12:30:49 -0800 (PST) Message-ID: <4f3c32a5-54cf-dcba-afe2-1f08b3f48b16@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1669149047; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=su4lExLppv6Rxu//8H+gMwaH+VUYLFFC4wdHiMQwUBQ=; b=aC5vDIEsyoiFi9pCRocHFiWqyEh3pbkUkpAOEqKDkcF4fcAMu6mrQtBi52fBs0dmb4Cp++ hzt46IjzkwWnE6Q1IdlNRRhiSqeWhk2FZcss/C7foCl3PjjXAWpwbbDQSB2XMu98dpFf/D DGf0V6BfPjLr6mBxLAm4UoscVXzQdlc= Date: Tue, 22 Nov 2022 13:30:43 -0700 MIME-Version: 1.0 Subject: Re: [PATCH v2] tests/nvme: Add admin-passthru+reset race test Content-Language: en-US To: Klaus Jensen , Keith Busch Cc: linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, Shin'ichiro Kawasaki , Chaitanya Kulkarni , Christoph Hellwig , Sagi Grimberg References: <20221117212210.934-1-jonathan.derrick@linux.dev> <7dcb9e3c-aa3e-b7b9-fc30-59281d581fd0@linux.dev> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Jonathan Derrick In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 11/22/2022 1:26 AM, Klaus Jensen wrote: > On Nov 21 16:04, Keith Busch wrote: >> [cc'ing Klaus] >> >> On Mon, Nov 21, 2022 at 03:49:45PM -0700, Jonathan Derrick wrote: >>> On 11/21/2022 3:34 PM, Jonathan Derrick wrote: >>>> On 11/21/2022 1:55 PM, Keith Busch wrote: >>>>> On Thu, Nov 17, 2022 at 02:22:10PM -0700, Jonathan Derrick wrote: >>>>>> I seem to have isolated the error mechanism for older kernels, but 6.2.0-rc2 >>>>>> reliably segfaults my QEMU instance (something else to look into) and I don't >>>>>> have any 'real' hardware to test this on at the moment. It looks like several >>>>>> passthru commands are able to enqueue prior/during/after resetting/connecting. >>>>> >>>>> I'm not seeing any problem with the latest nvme-qemu after several dozen >>>>> iterations of this test case. In that environment, the formats and >>>>> resets complete practically synchronously with the call, so everything >>>>> proceeds quickly. Is there anything special I need to change? >>>>> >>>> I can still repro this with nvme-fixes tag, so I'll have to dig into it myself >>> Here's a backtrace: >>> >>> Thread 1 "qemu-system-x86" received signal SIGSEGV, Segmentation fault. >>> [Switching to Thread 0x7ffff7554400 (LWP 531154)] >>> 0x000055555597a9d5 in nvme_ctrl (req=0x7fffec892780) at ../hw/nvme/nvme.h:539 >>> 540 return sq->ctrl; >>> (gdb) backtrace >>> #0 0x000055555597a9d5 in nvme_ctrl (req=0x7fffec892780) at ../hw/nvme/nvme.h:539 >>> #1 0x0000555555994360 in nvme_format_bh (opaque=0x5555579dd000) at ../hw/nvme/ctrl.c:5852 >> >> Thanks, looks like a race between the admin queue format's bottom half, >> and the controller reset tearing down that queue. I'll work with Klaus >> on that qemu side (looks like a well placed qemu_bh_cancel() should do >> it). >> > > Yuck. Bug located and quelched I think. > > Jonathan, please try > > https://lore.kernel.org/qemu-devel/20221122081348.49963-2-its@irrelevant.dk/ > > This fixes the qemu crash, but I still see a "nvme still not live after > 42 seconds!" resulting from the test. I'm seeing A LOT of invalid > submission queue doorbell writes: > > pci_nvme_ub_db_wr_invalid_sq in nvme_process_db: submission queue doorbell write for nonexistent queue, sqid=0, ignoring > > Tested on a 6.1-rc4. Good change, just defers it a bit for me: Thread 1 "qemu-system-x86" received signal SIGSEGV, Segmentation fault. [Switching to Thread 0x7ffff7554400 (LWP 559269)] 0x000055555598922e in nvme_enqueue_req_completion (cq=0x0, req=0x7fffec141310) at ../hw/nvme/ctrl.c:1390 1390 assert(cq->cqid == req->sq->cqid); (gdb) backtrace #0 0x000055555598922e in nvme_enqueue_req_completion (cq=0x0, req=0x7fffec141310) at ../hw/nvme/ctrl.c:1390 #1 0x000055555598a7a7 in nvme_misc_cb (opaque=0x7fffec141310, ret=0) at ../hw/nvme/ctrl.c:2002 #2 0x000055555599448a in nvme_do_format (iocb=0x55555770ccd0) at ../hw/nvme/ctrl.c:5891 #3 0x00005555559942a9 in nvme_format_ns_cb (opaque=0x55555770ccd0, ret=0) at ../hw/nvme/ctrl.c:5828 #4 0x0000555555dda018 in blk_aio_complete (acb=0x7fffec1fccd0) at ../block/block-backend.c:1501 #5 0x0000555555dda2fc in blk_aio_write_entry (opaque=0x7fffec1fccd0) at ../block/block-backend.c:1568 #6 0x0000555555f506b9 in coroutine_trampoline (i0=-331119632, i1=32767) at ../util/coroutine-ucontext.c:177 #7 0x00007ffff77c84e0 in __start_context () at ../sysdeps/unix/sysv/linux/x86_64/__start_context.S:91 #8 0x00007ffff4ff2bd0 in () #9 0x0000000000000000 in ()