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 X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 723F4C433E7 for ; Tue, 13 Oct 2020 19:12:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D976220EDD for ; Tue, 13 Oct 2020 19:12:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="gH+pocIJ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729971AbgJMTMg (ORCPT ); Tue, 13 Oct 2020 15:12:36 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:37236 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729530AbgJMTMg (ORCPT ); Tue, 13 Oct 2020 15:12:36 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1602616354; 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=+Geoviw+gNgwSk9MTAZob0fo0cDmAP4quy2bMV3V7xg=; b=gH+pocIJ0078VmUV7UA2pqY4LdnU0LYFcxgsFyweEnPm1ksWrWgnTh/xU6Isp3uY6Ar0uP P9hQKkiHFbpMFUkpC0X/si7wvUSfbrJb80OJ6U0zYWJavm351qtibI1OFustkVLWLXGAj0 k2rt4dF7hitQtfccHOGSy4DovRZUgmE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-226-ejcES3vtPsmfzayTtJ1XYA-1; Tue, 13 Oct 2020 15:12:30 -0400 X-MC-Unique: ejcES3vtPsmfzayTtJ1XYA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C4A281868410; Tue, 13 Oct 2020 19:12:29 +0000 (UTC) Received: from ovpn-118-16.rdu2.redhat.com (ovpn-118-16.rdu2.redhat.com [10.10.118.16]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0946960C07; Tue, 13 Oct 2020 19:12:22 +0000 (UTC) Message-ID: Subject: Re: Unbreakable loop in fuse_fill_write_pages() From: Qian Cai To: Vivek Goyal Cc: Miklos Szeredi , Alexander Viro , Stefan Hajnoczi , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, virtio-fs@redhat.com Date: Tue, 13 Oct 2020 15:12:22 -0400 In-Reply-To: <20201013185808.GA164772@redhat.com> References: <7d350903c2aa8f318f8441eaffafe10b7796d17b.camel@redhat.com> <20201013184026.GC142988@redhat.com> <20201013185808.GA164772@redhat.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Tue, 2020-10-13 at 14:58 -0400, Vivek Goyal wrote: > I am wondering if virtiofsd still alive and responding to requests? I > see another task which is blocked on getdents() for more than 120s. > > [10580.142571][ T348] INFO: task trinity-c36:254165 blocked for more than 123 > +seconds. > [10580.143924][ T348] Tainted: G O 5.9.0-next-20201013+ #2 > [10580.145158][ T348] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" > +disables this message. > [10580.146636][ T348] task:trinity-c36 state:D stack:26704 pid:254165 > ppid: > +87180 flags:0x00000004 > [10580.148260][ T348] Call Trace: > [10580.148789][ T348] __schedule+0x71d/0x1b50 > [10580.149532][ T348] ? __sched_text_start+0x8/0x8 > [10580.150343][ T348] schedule+0xbf/0x270 > [10580.151044][ T348] schedule_preempt_disabled+0xc/0x20 > [10580.152006][ T348] __mutex_lock+0x9f1/0x1360 > [10580.152777][ T348] ? __fdget_pos+0x9c/0xb0 > [10580.153484][ T348] ? mutex_lock_io_nested+0x1240/0x1240 > [10580.154432][ T348] ? find_held_lock+0x33/0x1c0 > [10580.155220][ T348] ? __fdget_pos+0x9c/0xb0 > [10580.155934][ T348] __fdget_pos+0x9c/0xb0 > [10580.156660][ T348] __x64_sys_getdents+0xff/0x230 > > May be virtiofsd crashed and hence no requests are completing leading > to a hard lockup? No, it was not crashed. After I had to forcibly close the guest, the virtiofsd daemon will exit normally. However, I can't tell exactly if the virtiofsd daemon was still functioning normally. I'll enable the debug and retry to see if there is anything interesting.