From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: 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)) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id B986F8A9D8 for ; Fri, 21 Oct 2022 10:02:41 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 9BF371EA9A for ; Fri, 21 Oct 2022 10:02:41 +0200 (CEST) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [94.136.29.106]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS for ; Fri, 21 Oct 2022 10:02:40 +0200 (CEST) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id 820FA44AED for ; Fri, 21 Oct 2022 10:02:40 +0200 (CEST) Message-ID: <2e5dd520-d6b9-b6d9-fb66-148678cdd983@proxmox.com> Date: Fri, 21 Oct 2022 10:02:35 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.3.0 To: pve-devel@lists.proxmox.com References: <20220902124409.42944-1-f.ebner@proxmox.com> Content-Language: en-US From: Fiona Ebner In-Reply-To: <20220902124409.42944-1-f.ebner@proxmox.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-SPAM-LEVEL: Spam detection results: 0 AWL 0.029 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment NICE_REPLY_A -0.001 Looks like a legit reply (A) SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record URIBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to URIBL was blocked. See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block for more information. [proxmox.com] Subject: Re: [pve-devel] [RFC v2 kernel] backport patch to fix TSC scaling for SVM X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 21 Oct 2022 08:02:41 -0000 Am 02.09.22 um 14:44 schrieb Fiona Ebner: > The following issue reported on the community forum [0] is likely > fixed by this. > > In my case, loading a VM snapshot that originally was taken on an > Intel CPU on my AMD-based host often caused problems in other VMs. In > particular, it often led to CPU stalls, and sometimes clock jumps far > into the future. With this backport applied, everything seems to run > smoothly even after loading the "bad" snapshot 10 times. > > The backport from upstream commit 11d39e8cc43e ("KVM: SVM: fix tsc > scaling cache logic consisted of dropping the parts for nested TSC > scaling, which is not yet present in our kernel, renaming the constant > for the default ratio, and some context changes. > > [0] https://forum.proxmox.com/threads/112756/ > > Signed-off-by: Fiona Ebner > --- > > Changes from v1: > * Alternative approach backporting the fix of the bad commit. > Ping. This still is an issue with 5.15.64-1-pve and users hit it semi-regularly [0](likely [1])[2]. This backport still fixes it for me. Alternatively, we can go for the revert[3] (but I didn't test the revert with 5.15.64-1-pve yet). [0]: https://forum.proxmox.com/threads/112756/post-505796 [1]: https://forum.proxmox.com/threads/116792/ [2]: https://forum.proxmox.com/threads/116683/ [3]: https://lists.proxmox.com/pipermail/pve-devel/2022-August/053814.html