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 BF3CEC433EF for ; Tue, 17 May 2022 21:16:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238483AbiEQVQL (ORCPT ); Tue, 17 May 2022 17:16:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41214 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240732AbiEQVQK (ORCPT ); Tue, 17 May 2022 17:16:10 -0400 Received: from out2-smtp.messagingengine.com (out2-smtp.messagingengine.com [66.111.4.26]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2E676B1CE for ; Tue, 17 May 2022 14:16:06 -0700 (PDT) Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailout.nyi.internal (Postfix) with ESMTP id B85F85C0180; Tue, 17 May 2022 17:16:03 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute3.internal (MEProxy); Tue, 17 May 2022 17:16:03 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rath.org; h=cc :cc:content-transfer-encoding:content-type:date:date:from:from :in-reply-to:in-reply-to:message-id:mime-version:references :reply-to:sender:subject:subject:to:to; s=fm2; t=1652822163; x= 1652908563; bh=cnAzkdmvoPxdDd20e9pP5gA4i8RocZR9hT0QrY+6HuQ=; b=1 Dn5xOoHBQvyvW7nXPVGeL/KVkXHkrmxLfyfxUuYsJIRdXMf/rA0ScrGeXcuq9OGC M6Wo5Ox6mukbQg8beB3Gozg8UsOeYBPL5S9Ifs7D0WYW4gJJhPTXJOw6aqbZ43gJ Bre4DVx1Scx8X0b0RBNoJxERH19lDbviDtvP8R4qc/rI2dnMJdyrwnF9HFSwEm7r z8GnNi0zx2sw2e/aU+sWI+nBdiLewWcSEBYBtYcVIt7iXqnptT2t8zm1iENlKDhb /sry9p4Nye1JH2GsLBQPBdsodwTH2NXgmuhdo9pMXWstRkOFBvIq+FPZlWdmeFl+ MvzsexE9isdy9f8DRcCxQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding :content-type:date:date:feedback-id:feedback-id:from:from :in-reply-to:in-reply-to:message-id:mime-version:references :reply-to:sender:subject:subject:to:to:x-me-proxy:x-me-proxy :x-me-sender:x-me-sender:x-sasl-enc; s=fm1; t=1652822163; x= 1652908563; bh=cnAzkdmvoPxdDd20e9pP5gA4i8RocZR9hT0QrY+6HuQ=; b=s RjPk4vg9l96heB3HzXwGekO/mGoTqsb4s5dUMAUSdHw+Bs05ku/m2RvVV5YV4Zxn 2SDnwfs58iraCY5t/lDE7t5TMuYRXTdp+CB6g7ua2jYYJRydGmG3FxxuT33b0ZGl ddwdnRjR432QlVzWbl4YI3/G5yxcvwdaoGhuhQtDlaFq6xU+8ezetN2tkKawCV4Y klz/H5Ry+WVXInKd3yiZawsQvfbIcI76KeT0aTKQbLck6FXI/o2snxH0/14Qhi/U 5m2AqbMrIcYh3PsuisEMlQuZQAS3kCjMGB9VQDXCmnPgDSfqj/TlUTcCa9JWt0hA BOOxHerNJGm9+sSSc0PnA== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvfedrheejgdduheehucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhephffvvefufhffjgfkfgggtgfgsehtqhdttddtreejnecuhfhrohhmpefpihhk ohhlrghushcutfgrthhhuceopfhikhholhgruhhssehrrghthhdrohhrgheqnecuggftrf grthhtvghrnhepvddujeffvdevfeduhfeiueffgfehgfekieeuffelieeijeegieevudeh feekhfehnecuffhomhgrihhnpehgihhthhhusgdrtghomhdpuggvsghirghnrdhorhhgne cuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomheppfhikhho lhgruhhssehrrghthhdrohhrgh X-ME-Proxy: Feedback-ID: i53a843ae:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Tue, 17 May 2022 17:16:02 -0400 (EDT) Received: from vostro.rath.org (vostro [192.168.12.4]) by ebox.rath.org (Postfix) with ESMTPS id 66FA576E; Tue, 17 May 2022 21:16:01 +0000 (UTC) Received: by vostro.rath.org (Postfix, from userid 1000) id 0EFC472A20; Tue, 17 May 2022 22:16:01 +0100 (BST) From: Nikolaus Rath To: "yukuai (C)" Cc: "Richard W.M. Jones" , , , Josef Bacik Subject: Re: [Libguestfs] Communication issues between NBD driver and NBDKit server References: <04a0a06b-e6dc-48b7-bc29-105dab888a56@www.fastmail.com> <20220515180525.GF8021@redhat.com> <87czgelidg.fsf@vostro.rath.org> <20220515192505.GJ1127@redhat.com> <1f37a75a-83b5-af8e-0dd3-6475652ab218@huawei.com> Mail-Copies-To: never Mail-Followup-To: "yukuai (C)" , "Richard W.M. Jones" , , , Josef Bacik Date: Tue, 17 May 2022 22:16:01 +0100 In-Reply-To: <1f37a75a-83b5-af8e-0dd3-6475652ab218@huawei.com> (yukuai's message of "Mon, 16 May 2022 09:08:08 +0800") Message-ID: <87a6bflv1q.fsf@vostro.rath.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On May 16 2022, "yukuai (C)" wrote: > On 2022/05/16 3:25, Richard W.M. Jones wrote: >> On Sun, May 15, 2022 at 08:12:59PM +0100, Nikolaus Rath wrote: >>> Do you see any way for this to happen? >> I think it's impossible. A more likely explanation follows. >> If you look at the kernel code, the NBD_CMD_INFLIGHT command flag is >> cleared when a command times out: >> https://github.com/torvalds/linux/blob/0cdd776ec92c0fec768c7079331804= d3e52d4b27/drivers/block/nbd.c#L407 >> That's the place where it would have printed the "Possible stuck >> request" message. >> Some time later, nbdkit actually replies to the message (for the first >> and only time) and in that code the flag is checked and found to be >> clear already, causing the "Suspicious reply" message to be printed: > Hi, > > You are right, can you try the following patch? > > https://lists.debian.org/nbd/2022/04/msg00212.html Ah, I guess that makes sense. I thought that not specifying a timeout meant "never time out". I'll set this to a large value and report back if the problem recurs. Thanks! -Nikolaus --=20 GPG Fingerprint: ED31 791B 2C5C 1613 AF38 8B8A D113 FCAC 3C4E 599F =C2=BBTime flies like an arrow, fruit flies like a Banana.=C2= =AB