From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <f.ebner@proxmox.com> Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id BE24068054 for <pve-devel@lists.proxmox.com>; Fri, 15 Jan 2021 08:43:24 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id A617721E5B for <pve-devel@lists.proxmox.com>; Fri, 15 Jan 2021 08:42:54 +0100 (CET) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [212.186.127.180]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS id 85ADA21E4B for <pve-devel@lists.proxmox.com>; Fri, 15 Jan 2021 08:42:53 +0100 (CET) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id 535384427B for <pve-devel@lists.proxmox.com>; Fri, 15 Jan 2021 08:42:53 +0100 (CET) To: Thomas Lamprecht <t.lamprecht@proxmox.com>, Proxmox VE development discussion <pve-devel@lists.proxmox.com> References: <20210111140024.13377-1-f.ebner@proxmox.com> <c573add7-5db1-d3f5-2deb-d2da3e99768d@proxmox.com> <85d4649e-faaa-3cbb-3b72-f5cb3caa006b@proxmox.com> From: Fabian Ebner <f.ebner@proxmox.com> Message-ID: <901a86b2-f3d7-ff34-c7a0-7392f55012ee@proxmox.com> Date: Fri, 15 Jan 2021 08:47:46 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: <85d4649e-faaa-3cbb-3b72-f5cb3caa006b@proxmox.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-SPAM-LEVEL: Spam detection results: 0 AWL 0.111 Adjusted score from AWL reputation of From: address KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment NICE_REPLY_A -0.237 Looks like a legit reply (A) RCVD_IN_DNSWL_MED -2.3 Sender listed at https://www.dnswl.org/, medium trust SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Subject: Re: [pve-devel] [PATCH v2 qemu-server 1/2] tests: mock storage locking for migration tests X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion <pve-devel.lists.proxmox.com> List-Unsubscribe: <https://lists.proxmox.com/cgi-bin/mailman/options/pve-devel>, <mailto:pve-devel-request@lists.proxmox.com?subject=unsubscribe> List-Archive: <http://lists.proxmox.com/pipermail/pve-devel/> List-Post: <mailto:pve-devel@lists.proxmox.com> List-Help: <mailto:pve-devel-request@lists.proxmox.com?subject=help> List-Subscribe: <https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel>, <mailto:pve-devel-request@lists.proxmox.com?subject=subscribe> X-List-Received-Date: Fri, 15 Jan 2021 07:43:24 -0000 On 12.01.21 12:07, Thomas Lamprecht wrote: > first, I overlooked your v2 due to lack of reply to Stefans comment there I did > not actually thought there would come one, but my followup seems mostly in line > with your patch here, so no real harm done.. > Sorry, in the future I'll try and send a quick response to the old version before sending out the new one. At least if the old version is not older than a month or so. > On 12.01.21 09:03, Fabian Ebner wrote: >> I didn't notice yesterday, but it's actually strange that volume_is_base_and_used uses a storage lock. Its callers that plan to change volumes on the storage based on the check need to hold the lock instead. Otherwise it can happen that: >> 1. volume_is_base_and_used is called and the result is used to decide how to branch >> 2. situation on the storage changes in the meantime >> 3. the branch we are taking might not be the one we should be taking anymore >> >> vdisk_free already uses its own lock around both the __no_lock-variant of the check and the modification on the storage it does, so it's fine. >> >> The only two callers for the normal variant are in qemu-server and they both serve as preliminary checks, while the real modification for both of them happens with vdisk_free. One of the callers makes the mocking below necessary, but it wouldn't if we were to remove the storage locking from volume_is_base_and_used. > > Sounds sensible without looking into it in depth yet, can you come up with a patch > to do so and look at the specifics? > Yes, will do.