From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id BD927C3DA7F for ; Thu, 15 Aug 2024 17:00:31 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5677B6B017E; Thu, 15 Aug 2024 13:00:31 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 517006B017F; Thu, 15 Aug 2024 13:00:31 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 405EC6B0180; Thu, 15 Aug 2024 13:00:31 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 223CD6B017E for ; Thu, 15 Aug 2024 13:00:31 -0400 (EDT) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 990DE121720 for ; Thu, 15 Aug 2024 17:00:30 +0000 (UTC) X-FDA: 82455093420.18.3360D6A Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by imf12.hostedemail.com (Postfix) with ESMTP id 0E7C040012 for ; Thu, 15 Aug 2024 17:00:27 +0000 (UTC) Authentication-Results: imf12.hostedemail.com; dkim=none; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=arm.com (policy=none); spf=pass (imf12.hostedemail.com: domain of cmarinas@kernel.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=cmarinas@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1723741147; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=pI24eK1NWUK0log+UWdFFYsQt9zGY4QjiSAKS1WIr2Y=; b=UzvbK42u3iiFAoKENUme82CTWpenJrsxL9X9QrW2cFyYkUb+H8eFGKLs/07ZbrRAUjEd2g 8lxFQ2FjnvRFDKRb5EGYsakFNHg+s22ffB7lGrsCa/rDS2YteV/WqgjKAkq3UPJJMzYH9V U2yt5+eVYTNFXCLMAqt0WqDa9K+sowA= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1723741147; a=rsa-sha256; cv=none; b=CA9VJnEoaf4M/Qd73P0t3QKu+KI4TerTV8HBiDCwShLaU8RCNUARL3vkj0JBBMginm1aht Z0/Mwqb05WCO3xKhbvTtGw7hPyr+HOEC4AqMeT3QjtnYr6DnHIoGMy+g4whqaJ/oz8DTFt 6+FZxzcTm0BAhipC55fRDYL+3epdoEI= ARC-Authentication-Results: i=1; imf12.hostedemail.com; dkim=none; dmarc=fail reason="SPF not aligned (relaxed), No valid DKIM" header.from=arm.com (policy=none); spf=pass (imf12.hostedemail.com: domain of cmarinas@kernel.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=cmarinas@kernel.org Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id 0D0D8CE1D1D; Thu, 15 Aug 2024 17:00:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7AED9C32786; Thu, 15 Aug 2024 17:00:17 +0000 (UTC) Date: Thu, 15 Aug 2024 18:00:15 +0100 From: Catalin Marinas To: Mark Brown Cc: Will Deacon , Jonathan Corbet , Andrew Morton , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Arnd Bergmann , Oleg Nesterov , Eric Biederman , Shuah Khan , "Rick P. Edgecombe" , Deepak Gupta , Ard Biesheuvel , Szabolcs Nagy , Kees Cook , "H.J. Lu" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Florian Weimer , Christian Brauner , Thiago Jung Bauermann , Ross Burton , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org Subject: Re: [PATCH v10 04/40] arm64: Document boot requirements for Guarded Control Stacks Message-ID: References: <20240801-arm64-gcs-v10-0-699e2bd2190b@kernel.org> <20240801-arm64-gcs-v10-4-699e2bd2190b@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240801-arm64-gcs-v10-4-699e2bd2190b@kernel.org> X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 0E7C040012 X-Stat-Signature: g79hcqz8cpqyjh797c9opzgacnhgf8zu X-Rspam-User: X-HE-Tag: 1723741227-604379 X-HE-Meta: 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 iTriNJBy QXkeTpqLWac4b/DAdvI9jGC0jt0/KNhqIIhaI2HdhnvpuhHfXXraDfddHu8xc91Xyz1WneuRIhRc6yuRSEg7O7b3GByOXX+ifbHOHnyEtEuHayJClT02d/d5kHRPgAEmadlJPQI84YnYEHBD6ZLiS/6Kq/q0+oyzNU+4MMXE4YHVC61u0NeAcniVrrBQgyW5+isEDEt/XNksZSbw6AHm6BvBYCq/tCPrAt8VDDi7vEoMN49IbnDnWjmM40md8WUdf5djsF/p3aUvqhU+1JyRl9qFVT7mr+yoMy7TRNxep6CCkJuHxOunfno2CpgFn8O+9RsZGL14PulyeH3tFk/vEDcPnusDNzK83TtKxkj3ij2MemUvdhwPCzHDJM3lUS+9l52HgV/MvfekmOFvAhvFROR9FSqsGbzNM3CE8 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 Thu, Aug 01, 2024 at 01:06:31PM +0100, Mark Brown wrote: > + - If EL2 is present: > + > + - GCSCR_EL2 must be initialised to 0. > + > + - If the kernel is entered at EL1 and EL2 is present: > + > + - GCSCR_EL1 must be initialised to 0. > + > + - GCSCRE0_EL1 must be initialised to 0. Currently booting.rst doesn't list *_EL1 registers to be initialised when the kernel is entered at EL1, that would usually be the responsibility of EL1. The exception is some bits in SCTLR_EL1 around not entering with the MMU and caches enabled. But here I think it makes sense to add these GCS registers since if some random bits are set, they can affect kernels (and user apps) that don't have GCS support. Don't we need HCRX_EL2.GCSEn to be set when entered at EL1? -- Catalin