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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 D3953C18E5B for ; Mon, 16 Mar 2020 12:40:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B4FA120663 for ; Mon, 16 Mar 2020 12:40:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731107AbgCPMkv (ORCPT ); Mon, 16 Mar 2020 08:40:51 -0400 Received: from poy.remlab.net ([94.23.215.26]:34268 "EHLO ns207790.ip-94-23-215.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731007AbgCPMkt (ORCPT ); Mon, 16 Mar 2020 08:40:49 -0400 Received: from basile.remlab.net (ip6-localhost [IPv6:::1]) by ns207790.ip-94-23-215.eu (Postfix) with ESMTP id B1B795FD86; Mon, 16 Mar 2020 13:40:47 +0100 (CET) From: =?UTF-8?q?R=C3=A9mi=20Denis-Courmont?= To: catalin.marinas@arm.com, will@kernel.org, linux-arm-kernel@lists.infradead.org Cc: mark.rutland@arm.com, linux-kernel@vger.kernel.org Subject: [PATCH 3/3] arm64: reduce trampoline data alignment Date: Mon, 16 Mar 2020 14:40:46 +0200 Message-Id: <20200316124046.103844-3-remi@remlab.net> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rémi Denis-Courmont The trampoline data, currently consisting of two relocated pointers, must be within a single page. However, there are no needs for it to start a page. This reduces the alignment to 16 bytes (with SDEI) or 8 bytes (without SDEI), which is sufficient to ensure that the data is entirely within a single page of the fixmap. Signed-off-by: Rémi Denis-Courmont --- arch/arm64/kernel/entry.S | 4 ++-- arch/arm64/mm/mmu.c | 5 ++--- 2 files changed, 4 insertions(+), 5 deletions(-) diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index af17fcb4aaea..b648f9fe1e33 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -858,12 +858,12 @@ SYM_CODE_END(tramp_exit_compat) .popsection // .entry.tramp.text #ifdef CONFIG_RANDOMIZE_BASE .pushsection ".rodata", "a" - .align PAGE_SHIFT #ifdef CONFIG_ARM_SDE_INTERFACE + .align 4 // all .rodata must be in a single fixmap page SYM_DATA_START(__sdei_asm_trampoline_next_handler) .quad __sdei_asm_handler SYM_DATA_END(__sdei_asm_trampoline_next_handler) -#endif +#endif /* CONFIG_ARM_SDE_INTERFACE */ SYM_DATA_START(__entry_tramp_data_start) .quad vectors SYM_DATA_END(__entry_tramp_data_start) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 9b08f7c7e6f0..6a0e75f48e7b 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -599,9 +599,8 @@ static int __init map_entry_trampoline(void) if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) { extern char __entry_tramp_data_start[]; - __set_fixmap(FIX_ENTRY_TRAMP_DATA, - __pa_symbol(__entry_tramp_data_start), - PAGE_KERNEL_RO); + pa_start = __pa_symbol(__entry_tramp_data_start) & PAGE_MASK; + __set_fixmap(FIX_ENTRY_TRAMP_DATA, pa_start, PAGE_KERNEL_RO); } return 0; -- 2.25.1