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Bottomley" , Helge Deller , linux-parisc@vger.kernel.org, Madhavan Srinivasan , Michael Ellerman , linuxppc-dev@lists.ozlabs.org, Paul Walmsley , Palmer Dabbelt , Albert Ou , linux-riscv@lists.infradead.org, Heiko Carstens , Vasily Gorbik , Alexander Gordeev , linux-s390@vger.kernel.org, Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Jonathan Corbet , Shuah Khan , linux-doc@vger.kernel.org Subject: Re: [PATCH 00/19] init: discoverable root partitions, a.k.a. an omittable "root=" cmdline option Message-ID: <20260615170432.GW2636677@ZenIV> References: <20260615-discoverable-root_partitions-v1-0-39c78fac42e2@kernel.org> X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260615-discoverable-root_partitions-v1-0-39c78fac42e2@kernel.org> Sender: Al Viro On Mon, Jun 15, 2026 at 06:08:56PM +0200, Vincent Mailhol wrote: > Tested with GRUB, which implements the LoaderDevicePartUUID EFI variable > in its bli module [3]. With this, I was able to boot a kernel with a > completely empty cmdline and no initrd. > > [1] The Discoverable Partitions Specification (DPS) > Link: https://uapi-group.org/specifications/specs/discoverable_partitions_specification/ > > [2] systemd-gpt-auto-generator > Link: https://www.freedesktop.org/software/systemd/man/latest/systemd-gpt-auto-generator.html > > [3] GRUB -- §16.2 bli > Link: https://www.gnu.org/software/grub/manual/grub/html_node/bli_005fmodule.html So what does that thing, tied to EFI as it is, have to do with architectures where * firmware is rather unlike EFI * firmware wouldn't know what to do with GPT * GRUB is *not* ported to, let alone used such as, say it, the very first one mentioned at your [1]? Or is that conditional upon "if anyone wants to design replacement firmware for those, and if they agree to follow our wishlist"?