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 X-Spam-Level: X-Spam-Status: No, score=-17.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5B428C433DB for ; Wed, 10 Mar 2021 17:17:14 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id F263364FC8 for ; Wed, 10 Mar 2021 17:17:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F263364FC8 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:Cc:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=s9oCWHZEJMr/xFgxQMHMHfT0D05sW/RSCHOegw/LBog=; b=qXButKROWy3aQNKcZGV71wDG2 UX2nIp0OMKaNEce3G2P448YLiyngUxusNlncePS1F1AgIuFuy5UDxOB1iuJFcVDuh/Q+cnvkrXbkA f0j1JXgimYM5obxx/8dR9IZXiaVYHkuyYnB/Q6VoxdBqVkhhTRNrVW5YT66xs0+McJRbt4NU1ESBz KF1qXaONsN1x/fuaOojBS4gOnyoNSMU1fkKi2xmYF1xpPpfWW5z4I008vMPOx88wE7wofZrZUNepW jp8ndKOkjOrszcSBHpAk7lhrQw3/8yue9soofiMjrWkpDiZ+iAyAK1ax6nkNa1nB337By5ZwTGek8 Ut/pcPp0w==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lK2RA-007JAw-EC; Wed, 10 Mar 2021 17:15:56 +0000 Received: from mail.kernel.org ([198.145.29.99]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lK2Qo-007J6B-0L for linux-arm-kernel@lists.infradead.org; Wed, 10 Mar 2021 17:15:35 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id 9B69F64FCA; Wed, 10 Mar 2021 17:15:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1615396532; bh=HjBDRZt+B3edx+gxLVunVxRowAVNFDhCOwCNUW4f/ko=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=F/YxZ2oENhH2YsQuW3iIcWlDLG7ASRRJycjejB6eLI6MjGeFcBG7h0kCcXKyXdJcT vnZ4mKxj2/D69kGV9vs5mZweAm8moJbmD7nWiQNuDO/SiZ3l8V0csM/x1V7E4Bblyt ihsdh39bv/BQdEjW2uZ+S1OsDnG8bDQEu/kljOVZXyV66XobHl8uYjhxwoI5zhYUge Lf0qGr7sTYoQlMmjZzgRajR9zr05L9A9GtK0ryuwuA49VM3vXFtUz+VkZ/yHbfo2V3 sqDSgMU5i9swqih7GxKVSH+rNiZFPo4d5eSWo32jhhywcUHOKwS6R8vrnC/Oy5STQm VHLvenvko7Idw== From: Ard Biesheuvel To: linux-arm-kernel@lists.infradead.org Cc: Ard Biesheuvel , Mark Salter , Will Deacon , James Morse , Catalin Marinas , Mark Rutland , Steve Capper , Anshuman Khandual Subject: [PATCH 4/5] arm64: mm: get rid of idmap_ptrs_per_pgd handling Date: Wed, 10 Mar 2021 18:15:14 +0100 Message-Id: <20210310171515.416643-5-ardb@kernel.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210310171515.416643-1-ardb@kernel.org> References: <20210310171515.416643-1-ardb@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210310_171534_231699_427849D6 X-CRM114-Status: GOOD ( 12.74 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org idmap_ptrs_per_pgd is stored and re-loaded in the very early boot path, and never referenced again. So a variable is not needed here. Furthermore, given that on the code path in question, PTRS_PER_PGD and '1 << (PHYS_MASK_SHIFT - PGDIR_SHIFT)' are guaranteed to be equal unless - the kernel was built for 48-bit VAs and 52-bit PAs, and - the kernel was loaded outside of the 48-bit addressable physical memory space (which is not supported by EFI to begin with), it seems reasonable to simply drop this code path altogether. Signed-off-by: Ard Biesheuvel --- arch/arm64/include/asm/mmu_context.h | 1 - arch/arm64/kernel/head.S | 9 +-------- arch/arm64/mm/mmu.c | 1 - 3 files changed, 1 insertion(+), 10 deletions(-) diff --git a/arch/arm64/include/asm/mmu_context.h b/arch/arm64/include/asm/mmu_context.h index bd02e99b1a4c..1307f5e27a5a 100644 --- a/arch/arm64/include/asm/mmu_context.h +++ b/arch/arm64/include/asm/mmu_context.h @@ -61,7 +61,6 @@ static inline void cpu_switch_mm(pgd_t *pgd, struct mm_struct *mm) * physical memory, in which case it will be smaller. */ extern u64 idmap_t0sz; -extern u64 idmap_ptrs_per_pgd; /* * Ensure TCR.T0SZ is set to the provided value. diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index f65d17a90204..da6e99fa4e08 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -344,16 +344,9 @@ SYM_FUNC_START_LOCAL(__create_page_tables) mov x4, EXTRA_PTRS create_table_entry x0, x3, EXTRA_SHIFT, x4, x5, x6 -#else - /* - * If VA_BITS == 48, we don't have to configure an additional - * translation level, but the top-level table has more entries. - */ - mov x4, #1 << (PHYS_MASK_SHIFT - PGDIR_SHIFT) - str_l x4, idmap_ptrs_per_pgd, x5 #endif 1: - ldr_l x4, idmap_ptrs_per_pgd + mov x4, PTRS_PER_PGD mov x5, x3 // __pa(__idmap_text_start) adr_l x6, __idmap_text_end // __pa(__idmap_text_end) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 338658cd1bea..569cf07ddb91 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -41,7 +41,6 @@ #define NO_CONT_MAPPINGS BIT(1) u64 idmap_t0sz = TCR_T0SZ(VA_BITS_MIN); -u64 idmap_ptrs_per_pgd = PTRS_PER_PGD; #ifdef CONFIG_ARM64_VA_BITS_52 u64 __section(".mmuoff.data.write") vabits_actual; -- 2.30.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel