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h=Date:From:To:Cc:Subject:In-Reply-To:From; b=K2QzZNWS5qvtc90qr2P/bmEBxGozBIkajd4g2BYgXL6Gp07XfQg2fDAaRimBjytR3 AnMyVUC1k+1MwDKxSrlcekXCA+Xo6jxwuhPGUKvb9LNjSYAl8jWKoOD6L8rj1fhHUR MBLQpicTg0GtL6aQ3jsYy8mAbKKMKwErUf1HScIM= Date: Wed, 8 Jul 2026 11:00:27 +0100 From: Catalin Marinas To: Shyam Saini Cc: Mike Rapoport , ardb@kernel.org, david@kernel.org, will@kernel.org, linux-arm-kernel@lists.infradead.org, akpm@linux-foundation.org, bboscaccy@linux.microsoft.com, bp@alien8.de, dapeng1.mi@linux.intel.com, ebiggers@kernel.org, elver@google.com, enelsonmoore@gmail.com, feng.tang@linux.alibaba.com, gpiccoli@igalia.com, kees@kernel.org, kuba@kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, lirongqing@baidu.com, peterz@infradead.org, rdunlap@infradead.org, tgopinath@linux.microsoft.com, tony.luck@intel.com, Lorenzo Pieralisi , Hanjun Guo , Sudeep Holla Subject: Re: [RFC v2 PATCH] reserve_mem: add support for static memory Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260630170911.43521-1-shyamsaini@linux.microsoft.com> X-Rspamd-Queue-Id: 49A10160002 X-Stat-Signature: ugwfnq7qq883i1ro16j78g8wyjd1izjq X-Rspam-User: X-Rspamd-Server: rspam12 X-HE-Tag: 1783504834-887013 X-HE-Meta: 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 ycBMcS8k /cK08w1o5/WJz1FNDRgZpo4qK+hL203ck/+Ww6whnOYgS41Irl1hyIndH77J0wrushStQWWUN/pLXT0SD2ni/T4QU6eGvnIQRNf/B7ilVNm88E43RTZnOt4DoHXLwdZOSEW9I5NKhWXnUfWdiN3E3w1KfiyTnPz6vgCRulzef5ShELbVKn2K8s2r7acm4Mg6fga8suVSzxMrJsJdI5AvJuPiW5DLUyeJzJ9/D2lbY0HUY7734ldq8OsKWEU9mRYYPuaO3ZXHVLY1VtJRdwy0BWhei9Q== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Hi Shyam, Adding Lorenzo, Hanjun, Sudeep. On Tue, Jun 30, 2026 at 10:09:11AM -0700, Shyam Saini wrote: > Following up on this, As Mike pointed that reserve_mem is best effort > reservation mechanism, so what is the recommended reliable Linux > mechanism, if any, to reserve a predetermined memory range during > early boot on ARM64/ACPI platforms for warm boot scenarios? KHO is > one option, but I'm specifically looking for a solution that preserves > the region across warm reboots. If you need ramoops-like support, I think ACPI ERST is a better fit and we don't need any memory reservation tricks. I'll let the arm ACPI maintainers comment further. -- Catalin