From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=217.140.110.172 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794410545; b=y2GAD1CWaxW3P2iJmcrfR3ElWeeql7wwFWkzIL+9x9tZfDVTusZLbHGuZsPLaHK4fTJF FsWtZ4+HzWynrRQzpGVjvc4SyWexIgMDsdfcVYfKU49MxcVDuLV7wf45/GSkZ4tu0qAeU zhaN2KxmeMq2qs+CH7S3bZdOtKxfibDDoBrEVcp2yJOX3kreA8FA6pOs2+mFGua+UiNHH SVOI9XvnoC/33vnh7V0+yoOnzGzokJxwN4hdsaKoPgma51Qz15Nd1JRH6oDCRzsHMID73 WTifrM80fUolylcAFpRuCKo7GgmU2xDHm2jnaFm0L62Uphp6iite+RMUKMEau280DPA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794410545; h=DMARC-Filter:Received:Received:DKIM-Signature:Message-ID:Date: MIME-Version:User-Agent:Subject:To:Cc:References:From: Content-Language:In-Reply-To:Content-Type:Content-Transfer-Encoding; bh=mBSo8+i91CrACZrxGkLXrZpH+5L8K8Z5H9NJzXzfrR4=; b=UbygsxD900NBtYx1yXo3SLqXvQe3Y4DxvIPjDJM1ejaPELYKvFexlBll7ua/sqTkGMlu kD9C36FhrUuRYR9K5OU4Oi6CYIzSkq7QJ1eF/QrjzYYvIjE2/XVsL5HP3CVGpf46kflmD OCoMPLask0NzITOOp07vpg9eFyksIBJdx8t4q3N3A0oKVjGQzwTG4/en4GSrWmVb3e0wo O18t1GIsiA/fHy62h9KYjleiMXtXTVPHsGe+b6D6LdNghlOZs+2qSdF7vjmBG3JoTKb8b Hl6YoPmEMG5eiyGFLqFfRiiS5JTtsZsdTFkWDjNmQZteEn8ShIHbDb6ozcLKxclWYmg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=CPe6sEoD; arc=none smtp.remote-ip=217.140.110.172 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 7378A606A32D; Wed, 11 Nov 2026 15:22:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 7378A606A32D 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.a=rsa-sha256 header.s=foss header.b=CPe6sEoD 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 C1AC61576; Wed, 11 Nov 2026 07:22:21 -0800 (PST) Received: from [10.43.20.72] (e126510-lin.lund.arm.com [10.43.20.72]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D2A903F632; Wed, 11 Nov 2026 07:22:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1794410544; bh=mBSo8+i91CrACZrxGkLXrZpH+5L8K8Z5H9NJzXzfrR4=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=CPe6sEoDXEq0CUSjZ6jny/Hfzg7F0nl2TvWdHaTVM/Z8om2nXFrbUEHiNinOsLi3G b+zM4dJw+QxdRaUrtNxakmzC6AiBkhYtoNt/T+Y94M/CGZNoMTkg+so51tIkMogts4 Zp7PhvG4gHcOkBuMpB9jhCJKm3Tc9Y9pOp0sQA68= Message-ID: <0a48af69-d0a9-410e-9d10-389eed0827c9@arm.com> Date: Wed, 11 Nov 2026 16:22:13 +0100 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH RFC v10 06/22] arm64: Disable EL2 trapping of POR_EL1 To: Mark Brown Cc: linux-hardening@vger.kernel.org, Andrew Morton , Ard Biesheuvel , Andy Lutomirski , Catalin Marinas , Dave Hansen , "David Hildenbrand (Arm)" , Jann Horn , Jeff Xu , Joey Gouly , Kees Cook , Linu Cherian , Linus Walleij , Marc Zyngier , Matthew Wilcox , Maxwell Bland , "Mike Rapoport (IBM)" , Peter Zijlstra , Pierre Langlois , =?UTF-8?Q?Pierre-Cl=C3=A9ment_Tosi?= , Quentin Perret , Rick Edgecombe , Ryan Roberts , Vlastimil Babka , Will Deacon , Yang Shi , Yeoreum Yun , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, x86@kernel.org, Ira Weiny , Lorenzo Stoakes , Thomas Gleixner References: <20261109-kpkeys-v10-0-aa6c4d9603bc@arm.com> <20261109-kpkeys-v10-6-aa6c4d9603bc@arm.com> <3500936b-4177-4ba0-a9df-7eb9d9d75b0a@sirena.org.uk> From: Kevin Brodsky Content-Language: en-GB In-Reply-To: <3500936b-4177-4ba0-a9df-7eb9d9d75b0a@sirena.org.uk> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 10/11/2026 16:29, Mark Brown wrote: > On Mon, Nov 09, 2026 at 03:58:31PM +0000, Kevin Brodsky wrote: > >> Make sure EL2 doesn't trap kernel accesses to POR_EL1 by setting the >> nPOR_EL1 bit in HFGRT{R,W}_EL2. > This wants a matching update in booting.rst as well for when the kernel > is booted at EL1. Good catch, in fact POE requirements are completely missing from booting.rst. Will post a separate patch for what we already need upstream (i.e. POE at EL0), and then expand the section in this patch. - Kevin