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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A1A1BC61DD3 for ; Thu, 3 Sep 2026 16:52:48 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 460FF6B0088; Thu, 3 Sep 2026 12:52:47 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 411FD6B008A; Thu, 3 Sep 2026 12:52:47 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 327CB6B009E; Thu, 3 Sep 2026 12:52:47 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 106296B0088 for ; Thu, 3 Sep 2026 12:52:47 -0400 (EDT) Received: from smtpin22.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 622FE1C22A5 for ; Thu, 3 Sep 2026 16:44:01 +0000 (UTC) X-FDA: 85173023082.22.2E882FD Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf16.hostedemail.com (Postfix) with ESMTP id B151E180009 for ; Thu, 3 Sep 2026 16:43:59 +0000 (UTC) Authentication-Results: imf16.hostedemail.com; dkim=pass header.d=arm.com header.s=foss header.b=tENFd08k; spf=pass (imf16.hostedemail.com: domain of kevin.brodsky@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=kevin.brodsky@arm.com; dmarc=pass (policy=none) header.from=arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1788453839; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=dnn/AYoSHbugk8b1Q7qn2t6H4dacOevAoUcpq3TWVlU=; b=Ufo7kXKARx64w++gOW9m659ew7BMW5hhAq1QuSK3Zm7BvsWneVvpVPMUKPePpUIi+226p+ nFKsAiH3STJsZQb1WtSg8xa/YUF1/BqGS/Numu6COzN469CITB2FoIADkMGfyeU871VkoD cNTKGPz1CGKZ9HWfRlvP2ieOni46Glk= ARC-Authentication-Results: i=1; imf16.hostedemail.com; dkim=pass header.d=arm.com header.s=foss header.b=tENFd08k; spf=pass (imf16.hostedemail.com: domain of kevin.brodsky@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=kevin.brodsky@arm.com; dmarc=pass (policy=none) header.from=arm.com ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1788453839; b=8PPl9M8tjewvLttYGTKZwwvitHYN+y7TCy5nGci3GG6HNQVCoJT4GtCK7ajHdQVxiKsISB JX90v9d7Zicczx6H3AEpljEiZzwBzJIA0z+Lk3Rwim03+BESNSvtEl5dm8aC5Cyw0lOttU 3lH1agwkNGIudqd01zXK4nc5Gt6UoJE= 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 1DF901596; Thu, 3 Sep 2026 09:43:54 -0700 (PDT) Received: from [10.57.6.2] (unknown [10.57.6.2]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7D35D3F673; Thu, 3 Sep 2026 09:43:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1788453837; bh=vWWRzkp0+9oMKve+SrPMb4YS1xG2sCsAn/SyP8y3BvA=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=tENFd08kZU5BI9AevP2DP6ylP6FwwMDs48XD+uMO7L0Bhz+L9BtkDN4I/SheeQ1Zu vh3KCgFk+KLoT4gq3yBTLs7TWPaLUAlYsO6mFXeDPTzA2CxeRUO++TSblimvJgqJm4 jYV5T0gUjWBtFbQkkOYjGhGmPiH+d6vIqx+nfiEE= Message-ID: Date: Thu, 3 Sep 2026 18:43:48 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH RFC v9 04/25] arm64: Introduce por_elx_set_pkey_perms() helper To: Linu Cherian Cc: linux-hardening@vger.kernel.org, Andrew Morton , Andy Lutomirski , Catalin Marinas , Dave Hansen , "David Hildenbrand (Arm)" , Jann Horn , Jeff Xu , Joey Gouly , Kees Cook , Linus Walleij , Marc Zyngier , Mark Brown , 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-arm-kernel@lists.infradead.org, linux-mm@kvack.org, x86@kernel.org, Ira Weiny , Lorenzo Stoakes , Thomas Gleixner References: <20260818-kpkeys-v9-0-743ad31b2c8f@arm.com> <20260818-kpkeys-v9-4-743ad31b2c8f@arm.com> From: Kevin Brodsky Content-Language: en-GB In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Stat-Signature: 3zf63i4gqqmft9cc5nexbpeof854faqz X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: B151E180009 X-Rspam-User: X-HE-Tag: 1788453839-648761 X-HE-Meta: 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 1gB0jPhc nO3DgQGSQwfMqw9Oh4g7KMV/TzbwVlHDudHH9mZSBh8vftkgpNCr8E78IPB9mpEel+GzMjD+KGcoyN3X0scL1Oa0GBceGFwze434tslgA6vMN4GGC5cnQjO/hjXaaPCjdzAfs37GI7cT0BQ0svujlAF1Xn6oAdn7ESPb4o/tui7kgWzM57KMV7u7uZIT5T+376E3D/lpm97zElMbCD2Pb/GJ9m/ASwV+BvH+m/dajZ9rQprWCR8OAlBlrCG1UAoKerMCKcBdYYFUhWX/cfUaZdzLSl1qFETI+OGDlVbrpsJqa4GnO1YFCI7Top30mtI43w6ix+Vi/7XifQAp4DZ8hMEXj/IYhvzy4tgkX3LbuQEGsseuklZBGZ/UxGkf3Penem8LOyonVg9gXb8Q= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 01/09/2026 16:42, Linu Cherian wrote: > Kevin, > > On Tue, Aug 18, 2026 at 03:08:46PM +0100, Kevin Brodsky wrote: >> Introduce a helper that sets the permissions of a given pkey >> (POIndex) in the POR_ELx format, and make use of it in >> arch_set_user_pkey_access(). >> >> new_por now represents the permissions of a single pkey, so rename >> it to new_perms and change its type accordingly. >> >> Reviewed-by: David Hildenbrand (Arm) >> Signed-off-by: Kevin Brodsky >> --- >> arch/arm64/include/asm/por.h | 7 +++++++ >> arch/arm64/mm/mmu.c | 26 ++++++++++---------------- >> 2 files changed, 17 insertions(+), 16 deletions(-) >> >> diff --git a/arch/arm64/include/asm/por.h b/arch/arm64/include/asm/por.h >> index d913d5b529e4..19b3dd1d43a0 100644 >> --- a/arch/arm64/include/asm/por.h >> +++ b/arch/arm64/include/asm/por.h >> @@ -31,4 +31,11 @@ static inline bool por_elx_allows_exec(u64 por, u8 pkey) >> return perm & POE_X; >> } >> >> +static inline u64 por_elx_set_pkey_perms(u64 por, u8 pkey, u8 perms) >> +{ >> + u64 shift = POR_ELx_PERM_SHIFT(pkey); >> + >> + return (por & ~(POE_MASK << shift)) | ((u64)perms << shift); > We could use standard bit field access macros here ? Good idea, will do. - Kevin