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 5280AC43334 for ; Thu, 16 Jun 2022 08:24:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346665AbiFPIYC (ORCPT ); Thu, 16 Jun 2022 04:24:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43524 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359683AbiFPIYA (ORCPT ); Thu, 16 Jun 2022 04:24:00 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id A21892494A for ; Thu, 16 Jun 2022 01:23:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1655367837; 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: in-reply-to:in-reply-to:references:references; bh=7B8uizFnHhCHPQVsQPdoP/5jXI/5okUyno9ZDVvYFaY=; b=inLaS3EA6acEZ2vDnxu9/spvX4y3UISvm5ioChYJsSWsLAXYmTWhNU7TjVdoUUKY4zUf3m 9IZikusTSrpQw7VucV80k5xmr5H8jLKZVq0FWVzMgPWpnU7bJ1Jn5Aj6CFn5R/8LR5F2jX jx8faDb6B/YmQeL/h1CZmS5vE6eJIkQ= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-299-z-3He7iGOhCqcJpXHSytnA-1; Thu, 16 Jun 2022 04:23:54 -0400 X-MC-Unique: z-3He7iGOhCqcJpXHSytnA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 912AE3817A67; Thu, 16 Jun 2022 08:23:53 +0000 (UTC) Received: from T590 (ovpn-8-22.pek2.redhat.com [10.72.8.22]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 5EC7E2166B26; Thu, 16 Jun 2022 08:23:48 +0000 (UTC) Date: Thu, 16 Jun 2022 16:23:43 +0800 From: Ming Lei To: John Garry Cc: Bart Van Assche , Jens Axboe , linux-block@vger.kernel.org, Christoph Hellwig Subject: Re: [PATCH] block: Fix handling of offline queues in blk_mq_alloc_request_hctx() Message-ID: References: <20220615210004.1031820-1-bvanassche@acm.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Thu, Jun 16, 2022 at 09:03:52AM +0100, John Garry wrote: > On 15/06/2022 22:00, Bart Van Assche wrote: > > This patch prevents that test nvme/004 triggers the following: > > > > UBSAN: array-index-out-of-bounds in block/blk-mq.h:135:9 > > index 512 is out of range for type 'long unsigned int [512]' > > Call Trace: > > show_stack+0x52/0x58 > > dump_stack_lvl+0x49/0x5e > > dump_stack+0x10/0x12 > > ubsan_epilogue+0x9/0x3b > > __ubsan_handle_out_of_bounds.cold+0x44/0x49 > > blk_mq_alloc_request_hctx+0x304/0x310 > > __nvme_submit_sync_cmd+0x70/0x200 [nvme_core] > > nvmf_connect_io_queue+0x23e/0x2a0 [nvme_fabrics] > > nvme_loop_connect_io_queues+0x8d/0xb0 [nvme_loop] > > nvme_loop_create_ctrl+0x58e/0x7d0 [nvme_loop] > > nvmf_create_ctrl+0x1d7/0x4d0 [nvme_fabrics] > > nvmf_dev_write+0xae/0x111 [nvme_fabrics] > > vfs_write+0x144/0x560 > > ksys_write+0xb7/0x140 > > __x64_sys_write+0x42/0x50 > > do_syscall_64+0x35/0x80 > > entry_SYSCALL_64_after_hwframe+0x44/0xae > > > > Cc: Christoph Hellwig > > Cc: Ming Lei > > Fixes: 20e4d8139319 ("blk-mq: simplify queue mapping & schedule with each possisble CPU") > > Signed-off-by: Bart Van Assche > > --- > > block/blk-mq.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/block/blk-mq.c b/block/blk-mq.c > > index 7a5558bbc7f6..1c09c6017ea9 100644 > > --- a/block/blk-mq.c > > +++ b/block/blk-mq.c > > @@ -579,6 +579,8 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q, > > if (!blk_mq_hw_queue_mapped(data.hctx)) > > goto out_queue_exit; > > cpu = cpumask_first_and(data.hctx->cpumask, cpu_online_mask); > > + if (cpu >= nr_cpu_ids) > > + goto out_queue_exit; > > Ming, Did you give up on this: > > https://lore.kernel.org/linux-block/20210818144428.896216-1-ming.lei@redhat.com/ Yeah, this approach has some big problem, see https://lore.kernel.org/linux-block/20210722160654.GA8344@lst.de/#t Thanks, Ming