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charset=us-ascii Content-Disposition: inline In-Reply-To: <20231228131056.602411-1-artem.kuzin@huawei.com> X-Rspamd-Queue-Id: CAF9E180019 X-Rspam-User: X-Rspamd-Server: rspam11 X-Stat-Signature: xs6gzf38o4u4cw8jn34tngg1yterbita X-HE-Tag: 1704881050-152067 X-HE-Meta: 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 3s9Gydk/ 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000735, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Dec 28, 2023 at 09:10:44PM +0800, artem.kuzin@huawei.com wrote: > There was a work previously published for ARM64 platform > by Russell King (arm64 kernel text replication). > We hope that it will be possible to push this technology forward together. Honestly, I don't think the arm64 kernel text replication is going to progress. I had zero feedback on the last posting, which suggests that there is very little interest in it. With Ard's suggestion to use pKVM for it, that's totally and utterly outside of my knowledge realm about how to implement that, and I have no idea what the implications of doing so would be - would it prevent being able to run KVM guests? How does it interact with the KVM hypervisor? Does it require nested virtualisation (which isn't supported on the platforms that Oracle are interested in.) Then there is now the pKVM hypervisor for kernel text replication would grab the memory it needs to replicate the kernel. Having been through all the different layers of firmware, boot loader etc the conclusion was that it's something that the kernel should be doing - and the code that Ard pointed me towards was firmware-based. So, right now I think arm64 kernel text replication is rather dead in the water. Honestly, I now utterly regret bringing up this idea inside Oracle. It has become something of a millstone around my neck. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!