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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (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 84776C3DA49 for ; Tue, 16 Jul 2024 09:07:07 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4WNY9Q0vTQz3dHK for ; Tue, 16 Jul 2024 19:07:06 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=arm.com (client-ip=217.140.110.172; helo=foss.arm.com; envelope-from=anshuman.khandual@arm.com; receiver=lists.ozlabs.org) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lists.ozlabs.org (Postfix) with ESMTP id 4WNY8y0nklz30Wg for ; Tue, 16 Jul 2024 19:06:38 +1000 (AEST) 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 CA2511063; Tue, 16 Jul 2024 02:06:30 -0700 (PDT) Received: from [10.163.52.225] (unknown [10.163.52.225]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 83B843F762; Tue, 16 Jul 2024 02:05:53 -0700 (PDT) Message-ID: <0f87e51e-f790-4302-896f-9b9a74ed7495@arm.com> Date: Tue, 16 Jul 2024 14:35:48 +0530 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 13/29] arm64: convert protection key into vm_flags and pgprot values To: Joey Gouly , linux-arm-kernel@lists.infradead.org References: <20240503130147.1154804-1-joey.gouly@arm.com> <20240503130147.1154804-14-joey.gouly@arm.com> Content-Language: en-US From: Anshuman Khandual In-Reply-To: <20240503130147.1154804-14-joey.gouly@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: szabolcs.nagy@arm.com, catalin.marinas@arm.com, dave.hansen@linux.intel.com, linux-mm@kvack.org, hpa@zytor.com, shuah@kernel.org, maz@kernel.org, x86@kernel.org, christophe.leroy@csgroup.eu, aneesh.kumar@kernel.org, mingo@redhat.com, naveen.n.rao@linux.ibm.com, will@kernel.org, npiggin@gmail.com, broonie@kernel.org, bp@alien8.de, kvmarm@lists.linux.dev, tglx@linutronix.de, oliver.upton@linux.dev, aneesh.kumar@linux.ibm.com, linux-fsdevel@vger.kernel.org, akpm@linux-foundation.org, linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 5/3/24 18:31, Joey Gouly wrote: > Modify arch_calc_vm_prot_bits() and vm_get_page_prot() such that the pkey > value is set in the vm_flags and then into the pgprot value. > > Signed-off-by: Joey Gouly > Cc: Catalin Marinas > Cc: Will Deacon > --- > arch/arm64/include/asm/mman.h | 8 +++++++- > arch/arm64/mm/mmap.c | 9 +++++++++ > 2 files changed, 16 insertions(+), 1 deletion(-) > > diff --git a/arch/arm64/include/asm/mman.h b/arch/arm64/include/asm/mman.h > index 5966ee4a6154..ecb2d18dc4d7 100644 > --- a/arch/arm64/include/asm/mman.h > +++ b/arch/arm64/include/asm/mman.h > @@ -7,7 +7,7 @@ > #include > > static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot, > - unsigned long pkey __always_unused) > + unsigned long pkey) > { > unsigned long ret = 0; > > @@ -17,6 +17,12 @@ static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot, > if (system_supports_mte() && (prot & PROT_MTE)) > ret |= VM_MTE; > > +#if defined(CONFIG_ARCH_HAS_PKEYS) > + ret |= pkey & 0x1 ? VM_PKEY_BIT0 : 0; > + ret |= pkey & 0x2 ? VM_PKEY_BIT1 : 0; > + ret |= pkey & 0x4 ? VM_PKEY_BIT2 : 0; 0x1, 0x2, 0x4 here are standard bit positions for their corresponding VM_KEY_XXX based protection values ? Although this is similar to what x86 is doing currently, hence just trying to understand if these bit positions here are related to the user visible ABI, which should be standardized ? Agree with previous comments about the need for system_supports_poe() based additional check for the above code block. > +#endif > + > return ret; > } > #define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey) > diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c > index 642bdf908b22..86eda6bc7893 100644 > --- a/arch/arm64/mm/mmap.c > +++ b/arch/arm64/mm/mmap.c > @@ -102,6 +102,15 @@ pgprot_t vm_get_page_prot(unsigned long vm_flags) > if (vm_flags & VM_MTE) > prot |= PTE_ATTRINDX(MT_NORMAL_TAGGED); > > +#ifdef CONFIG_ARCH_HAS_PKEYS > + if (vm_flags & VM_PKEY_BIT0) > + prot |= PTE_PO_IDX_0; > + if (vm_flags & VM_PKEY_BIT1) > + prot |= PTE_PO_IDX_1; > + if (vm_flags & VM_PKEY_BIT2) > + prot |= PTE_PO_IDX_2; > +#endif > + > return __pgprot(prot); > } > EXPORT_SYMBOL(vm_get_page_prot);