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b=mG5uWx77WE0EGnCrHbQasMsoBXvZLyPyefnHDo/kv1dErYEdI1ixpuJRy2SCwFJt8 lVCSDFtq2gEKcqR29ZP6JNVPZQobSCkg/IsOC4p/3Dgp6QvRkYbxJOtEqBxvkwxKsg 10gPrepuN9n3PonQTVtPdEmWnCGXSJxgx/6QAM9OQW7H/lFS1bG1wQ2xWQbcAfH1Ki HU4G5KYrRpareJGa4IVC5HrYOZr13dvUQj0Br2epvj/QlOUPAltIoDZfvuotLTFxz2 9LLBuQKO+rYqzfoQBXQ5m3NcTW+TsUdsGScsXteM/3JKOYFOWJJDdDtIuILWqBPyq5 PSMCpgFOK7XZg== Date: Sun, 21 Sep 2025 09:24:12 +0300 From: Mike Rapoport To: Jan Engelhardt Cc: Cong Wang , linux-kernel@vger.kernel.org, pasha.tatashin@soleen.com, Cong Wang , Andrew Morton , Baoquan He , Alexander Graf , Changyuan Lyu , kexec@lists.infradead.org, linux-mm@kvack.org Subject: Re: [RFC Patch 0/7] kernel: Introduce multikernel architecture support Message-ID: References: <20250918222607.186488-1-xiyou.wangcong@gmail.com> <3ns36rp5-rp37-1nns-9q43-op05or6s26nq@vanv.qr> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3ns36rp5-rp37-1nns-9q43-op05or6s26nq@vanv.qr> X-Rspamd-Queue-Id: 675E180004 X-Rspamd-Server: rspam05 X-Stat-Signature: kftz4odhs93rwyamixwoha1rzujnq8of X-Rspam-User: X-HE-Tag: 1758435861-233975 X-HE-Meta: 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 2bMgICjF cFVMjlxDt4yFtm7x4gl5WdM5/qu552grLR2roxZznaP4zH8mN5ivq4NfoKVd6R+t7gtOFpGv3/xWVh77KBx+7wM+QXouZbvjziI6wTy0YcQ5NgXL1YzvCrZxvS91ZTyLpi5po91Xyz9BcLKrBAm55N+BZUhnEAx4aFiFC8Lh1Aw59kq7MOmGnvjnxM2FmhYo+rfEC6ml7kY+W5mN2ceLAI+8MGW7FpyYP+zwct6mDqwXfE5ucvuONWpJQ0IcNECauD5tCS8ABVo3EndKCOU0Sr9vhXQWlVcU0ViTBMQM7OTgDf7+rC3PhIYA/TMQhH0CLbdHWG9SdPwZrnB08dWcLlxojbgqgl5R/ttSe3opbrrU7w/PHSpbnQWLVYX22rm0eLzoe X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, 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 Sun, Sep 21, 2025 at 07:54:31AM +0200, Jan Engelhardt wrote: > > On Friday 2025-09-19 00:25, Cong Wang wrote: > > >This patch series introduces multikernel architecture support, enabling > >multiple independent kernel instances to coexist and communicate on a > >single physical machine. > > > >Each kernel instance can run on dedicated CPU > >cores while sharing the underlying hardware resources. > > I initially read it in such a way that that kernels run without > supervisor, and thus necessarily cooperatively, on a system. > > But then I looked at > , The diagram also oversimplifies containers, with system containers the "OS" runs inside the container and only the kernel is shared. It's interesting to hear how the multikernel approach compare to system containers as well. > saw that there is a kernel on top of a kernel, to which my reactive > thought was: "well, that has been done before", e.g. User Mode Linux. > While UML does not technically talk to hardware directly, continuing > the thought "what's stopping a willing developer from giving /dev/mem > to the subordinate kernel". > > On second thought, a hypervisor is just some kind of "miniature > kernel" too (if generalizing very hard). > -- Sincerely yours, Mike.