From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id C55DD384CC2; Wed, 8 Jul 2026 10:00:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783504835; cv=none; b=AW0kt4LF6uw3EYQWJUhhOXe1WaEjVfSoCyuOZccD0Inrx14IP8kuROfo1kSOCgtt9pSTwtGlhO97KI6yZPQYSawhOJbEU4TNJ1nFyo4x3Mxn9L8oSsenp8I5nyEE2EzrjQCSO/4GKRiw6yzDAXCt0jwxkDHaLTQWQi6p6XioV9E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783504835; c=relaxed/simple; bh=8oFU73UDNb1/JzzX/59Hz8/SUvhrGo6jInm1l2EOvkk=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=SC5yzpSvK+qioOC/ZeUDXoB2yw9xxs6s9n7xuNKHvxQZbu1v9OHI8sJKa8fT88LErKD0Wv7SqF8UGnPqpPfMPvEmoukrMeUcc70wKyQucY2LtyHypMQa/u2IpIeSOZ5LNTHmeFtnZtmZIyP6FJ9MkTk5Oq4SEjUYmxIT3zmAEqk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=K2QzZNWS; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="K2QzZNWS" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B75871E5E; Wed, 8 Jul 2026 03:00:28 -0700 (PDT) Received: from arm.com (usa-sjc-mx-foss1.foss.arm.com [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 31A4B3F85F; Wed, 8 Jul 2026 03:00:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1783504833; bh=8oFU73UDNb1/JzzX/59Hz8/SUvhrGo6jInm1l2EOvkk=; 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: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260630170911.43521-1-shyamsaini@linux.microsoft.com> 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