From patchwork Wed May 8 16:15:57 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julien Grall X-Patchwork-Id: 10936223 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C84E692A for ; Wed, 8 May 2019 16:17:38 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B953A26490 for ; Wed, 8 May 2019 16:17:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id ADBA02821F; Wed, 8 May 2019 16:17:38 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 503EF26490 for ; Wed, 8 May 2019 16:17:38 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hOPEq-0008EW-3P; Wed, 08 May 2019 16:16:12 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hOPEo-0008EE-T5 for xen-devel@lists.xenproject.org; Wed, 08 May 2019 16:16:10 +0000 X-Inumbo-ID: 976a1332-71ac-11e9-90eb-eb305858670c Received: from foss.arm.com (unknown [217.140.101.70]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTP id 976a1332-71ac-11e9-90eb-eb305858670c; Wed, 08 May 2019 16:16:10 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B64EC80D; Wed, 8 May 2019 09:16:09 -0700 (PDT) Received: from e108454-lin.cambridge.arm.com (e108454-lin.cambridge.arm.com [10.1.196.50]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 830353F238; Wed, 8 May 2019 09:16:08 -0700 (PDT) From: Julien Grall To: xen-devel@lists.xenproject.org Date: Wed, 8 May 2019 17:15:57 +0100 Message-Id: <20190508161603.21964-2-julien.grall@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190508161603.21964-1-julien.grall@arm.com> References: <20190508161603.21964-1-julien.grall@arm.com> Subject: [Xen-devel] [PATCH v2 1/7] xen/arm: mm: Consolidate setting SCTLR_EL2.WXN in a single place X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Oleksandr_Tyshchenko@epam.com, Julien Grall , Stefano Stabellini , Andrii Anisov MIME-Version: 1.0 Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" X-Virus-Scanned: ClamAV using ClamSMTP The logic to set SCTLR_EL2.WXN is the same for the boot CPU and non-boot CPU. So introduce a function to set the bit and clear TLBs. This new function will help us to document and update the logic in a single place. Signed-off-by: Julien Grall Reviewed-by: Andrii Anisov Reviewed-by: Stefano Stabellini --- Changes in v2: - Fix typo in the commit message - Add Andrii's reviewed-by --- xen/arch/arm/mm.c | 22 +++++++++++++++------- 1 file changed, 15 insertions(+), 7 deletions(-) diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c index 01ae2cccc0..93ad118183 100644 --- a/xen/arch/arm/mm.c +++ b/xen/arch/arm/mm.c @@ -601,6 +601,19 @@ void __init remove_early_mappings(void) flush_xen_data_tlb_range_va(BOOT_FDT_VIRT_START, BOOT_FDT_SLOT_SIZE); } +/* + * After boot, Xen page-tables should not contain mapping that are both + * Writable and eXecutables. + * + * This should be called on each CPU to enforce the policy. + */ +static void xen_pt_enforce_wnx(void) +{ + WRITE_SYSREG32(READ_SYSREG32(SCTLR_EL2) | SCTLR_WXN, SCTLR_EL2); + /* Flush everything after setting WXN bit. */ + flush_xen_text_tlb_local(); +} + extern void switch_ttbr(uint64_t ttbr); /* Clear a translation table and clean & invalidate the cache */ @@ -702,10 +715,7 @@ void __init setup_pagetables(unsigned long boot_phys_offset) clear_table(boot_second); clear_table(boot_third); - /* From now on, no mapping may be both writable and executable. */ - WRITE_SYSREG32(READ_SYSREG32(SCTLR_EL2) | SCTLR_WXN, SCTLR_EL2); - /* Flush everything after setting WXN bit. */ - flush_xen_text_tlb_local(); + xen_pt_enforce_wnx(); #ifdef CONFIG_ARM_32 per_cpu(xen_pgtable, 0) = cpu0_pgtable; @@ -777,9 +787,7 @@ int init_secondary_pagetables(int cpu) /* MMU setup for secondary CPUS (which already have paging enabled) */ void mmu_init_secondary_cpu(void) { - /* From now on, no mapping may be both writable and executable. */ - WRITE_SYSREG32(READ_SYSREG32(SCTLR_EL2) | SCTLR_WXN, SCTLR_EL2); - flush_xen_text_tlb_local(); + xen_pt_enforce_wnx(); } #ifdef CONFIG_ARM_32