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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 732B6D58067 for ; Mon, 25 Nov 2024 11:35:37 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tFXND-0006NJ-Kz; Mon, 25 Nov 2024 06:35:24 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tFXN7-0006JN-Fj for qemu-devel@nongnu.org; Mon, 25 Nov 2024 06:35:18 -0500 Received: from 8.mo548.mail-out.ovh.net ([46.105.45.231]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tFXN3-0003zG-Ls for qemu-devel@nongnu.org; Mon, 25 Nov 2024 06:35:17 -0500 Received: from mxplan5.mail.ovh.net (unknown [10.108.2.162]) by mo548.mail-out.ovh.net (Postfix) with ESMTPS id 4XxkCK1MXvzyb7; Mon, 25 Nov 2024 11:35:09 +0000 (UTC) Received: from kaod.org (37.59.142.110) by DAG6EX1.mxp5.local (172.16.2.51) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.39; Mon, 25 Nov 2024 12:35:08 +0100 Authentication-Results: garm.ovh; auth=pass (GARM-110S004ecf68c51-6fd7-4511-9918-cbd6166b82b3, 9B13B6726B83599ED9C5792380F23B2D0625FF83) smtp.auth=groug@kaod.org X-OVh-ClientIp: 88.179.9.154 Date: Mon, 25 Nov 2024 12:35:05 +0100 From: Greg Kurz To: Christian Schoenebeck CC: , Subject: Re: [PATCH 0/6] 9pfs: fix fstat() after unlink() (with a Linux guest) Message-ID: <20241125123505.06ab0568@bahia> In-Reply-To: <192504804.CgdclvVjum@silver> References: <20241125094554.5e1b17ba@bahia> <192504804.CgdclvVjum@silver> X-Mailer: Claws Mail 4.3.0 (GTK 3.24.43; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [37.59.142.110] X-ClientProxiedBy: DAG2EX1.mxp5.local (172.16.2.11) To DAG6EX1.mxp5.local (172.16.2.51) X-Ovh-Tracer-GUID: fb02b864-27a6-4b39-b871-7265fe3c2330 X-Ovh-Tracer-Id: 6984238597570337245 X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: 0 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgeefuddrgeehgddvlecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfqggfjpdevjffgvefmvefgnecuuegrihhlohhuthemucehtddtnecunecujfgurhepfffhvfevuffkjghfofggtgfgihesthejredtredtvdenucfhrhhomhepifhrvghgucfmuhhriicuoehgrhhouhhgsehkrghougdrohhrgheqnecuggftrfgrthhtvghrnhephfffuedvgeekudegheevtdekheehveeffeetueevheefteegvedttdeghfefhfffnecuffhomhgrihhnpehgihhtlhgrsgdrtghomhdpghhithhhuhgsrdgtohhmnecukfhppeduvdejrddtrddtrddupdefjedrheelrddugedvrdduuddtpdekkedrudejledrledrudehgeenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepihhnvghtpeduvdejrddtrddtrddupdhmrghilhhfrhhomhepghhrohhugheskhgrohgurdhorhhgpdhnsggprhgtphhtthhopeefpdhrtghpthhtohepqhgvmhhupghoshhssegtrhhuuggvsgihthgvrdgtohhmpdhrtghpthhtohepqhgvmhhuqdguvghvvghlsehnohhnghhnuhdrohhrghdprhgtphhtthhopehqvghmuhdqshhtrggslhgvsehnohhnghhnuhdrohhrghdpoffvtefjohhsthepmhhoheegkegmpdhmohguvgepshhmthhpohhuth DKIM-Signature: a=rsa-sha256; bh=HfU8Yww8hGX8I9O7l/9Jtuy7OirpsAnG7B+gCgsB6eU=; c=relaxed/relaxed; d=kaod.org; h=From; s=ovhmo393970-selector1; t=1732534509; v=1; b=BKcM7NZ2PLIZEWjQSd47b3vBkKtH/F8j2CCYfLr5350ZH6Bp6GTy0g11McivYhF+o11XMo5g FLPMysxDBAfzVne4/xnd0TG0o5fGkOce+NC+SJRJuXqDezWdIezqFloU1zTj1Uy6bashl+VYuDY vsobX+ri0Xczy5fqucf3iV2Y5QTcb/wmFTIWr8PVHWm+2Xq41icQAktIfoo+WLpdW39uw3zGrst B/yKcxpp8pW+7zIbYEDwhp486zT5/YTzg08FkHOCNrp0A6kvKxxmY9o+YXq+biovhXWzk9Thkfa /s7i1wOc+0msLdtD2ExM5K06w9vFb/SM+1GaEKTaPIhvg== Received-SPF: pass client-ip=46.105.45.231; envelope-from=groug@kaod.org; helo=8.mo548.mail-out.ovh.net X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.93, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Mon, 25 Nov 2024 11:23:39 +0100 Christian Schoenebeck wrote: > On Monday, November 25, 2024 9:45:54 AM CET Greg Kurz wrote: > > On Sun, 24 Nov 2024 17:28:40 +0100 > > Christian Schoenebeck wrote: > > > > > This fixes an infamous, long standing bug: > > > https://gitlab.com/qemu-project/qemu/-/issues/103 > > > > > > > \o/ > > > > It is great if you manage to fix that once and far all ! > > > > > * Actual fix of this bug is patch 5. > > > > > > * Patches 1 and 6 add a test case to verify the expected behaviour. > > > > > > * The other patches (2, 3, 4) are basically just minor cleanup patches more > > > or less (un)related that I simply did not bother to send separately. > > > > > > Probably there are still other 9p request types that should be fixed for this > > > use-after-unlink idiom, but this series fixes the mentioned bug report as > > > described by reporter, so fair enough to round this up here for now. > > > > > > > When I last worked on that issue I had spotted some other places to fix. > > > > Maybe you can find some ideas for future work at : > > > > https://github.com/gkurz/qemu/tree/9p-attr-fixes > > Was there a reason why you left those patches on the attic? > Lack of cycles > What I am seeing is that it was not fixing Tgetattr (i.e. fstat() on guest), > so it wouldn't have fixed the original reporter's scenario, but they would > have brought things forward. So just wondering ... > Yeah the fix for Tgetattr was in some other series I had sent at the time but I did not get much feeback then... > /Christian > > Cheers, -- Greg