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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id EA143C624D4 for ; Thu, 3 Sep 2026 16:44:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=dnn/AYoSHbugk8b1Q7qn2t6H4dacOevAoUcpq3TWVlU=; b=zIN+y/ndWe0QB3NUE5GxcvZo4D p0eQBo3p2KL2R+Nb0y1CzpbXIx3qWATzKQMoNXifdqFm6EWIHdR4treYp/t9jQKIYsw1TnePScmLc OUN/ploQSmSkKQI49fSt9e8j8CgGSCePquE/0IM0EEp2NXkAxsB4v7zNMk1Ac4b9Y5akBkyiLVZZB IAMFIzVq9A7bqI1KvihXJAARsDfFFvODaUxSdR8F+rbZ4FyEoG0dMJbPTYjLsXsmyG49n9TY72xyl MD2rutyYbiBBeO4FhZclip4IEJkWoyiD744Rwrb9Y4egu+MxdzEr8VK69XKkKp8py3aSRRJorwHID Ynd83n0w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x2AXg-00000000CYd-2xAj; Thu, 03 Sep 2026 16:44:00 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x2AXe-00000000CXL-1mQQ for linux-arm-kernel@lists.infradead.org; Thu, 03 Sep 2026 16:43:59 +0000 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-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260903_094358_502206_B835DFB3 X-CRM114-Status: GOOD ( 14.22 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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