From patchwork Tue Nov 29 16:14:14 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 13058805 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 B7CE8C433FE for ; Tue, 29 Nov 2022 16:18:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; 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=UdbPA0f8agb0MhbMS+RzqKnKeGju6+nsbCcgYgAXnt4=; b=ecaXZ1vEK38wO0 CdjJplfWPryqhL5gabiruJS/s/WdCd5/g6km6YNqcw+NvPYC1OkYMGNs1dcmLtLo3I2Kom1Uaakcx lIdmmf8/8RN150dYJ54jTB6x9LMOBDfGRvKLsuB8JlTyWgpW5RCTTl87tVWMyqp69bbUhg33/dM5y vAfHmXH4ZndOBdEEq2DAgxy2gLb9S72CHVv+LVQS1NcdNIY/aT8UceRy984zRIfsueAhUwlZGMg1z 6S5Xj78BKl9LKiuWEN7XUOxW9j6ODx7Etp1rUk5g7RUY6FGXTJrXxWhfNNkX4xUzwGTcUBg55Qoi1 qtCuyc2v7QuRulYNfDUA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1p03I7-00A1LH-K6; Tue, 29 Nov 2022 16:17:04 +0000 Received: from ams.source.kernel.org ([145.40.68.75]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1p03Ff-00A0Xn-0Z for linux-arm-kernel@lists.infradead.org; Tue, 29 Nov 2022 16:14:32 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id AC946B811B8; Tue, 29 Nov 2022 16:14:28 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 190DDC43470; Tue, 29 Nov 2022 16:14:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1669738467; bh=U2iqnVkuhwtUu/qXPBf/2GNjjB270ekS914+aIpYPEc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FuZlmyujS1i8rwA8Tfj/9d6TBfTkhYZdnEt8WizSuHihX0SCcgl3cWFb4E5hd6jNv 84ZzeZNhTANzTjClBgrnDyWdcRsHJP8PfPIF1CkcNszkG9qJNbkjtZn5a7PvmAL8zB /1jNIK2Fd3ELYutzV7EcrhpBeKANBYQR2R+aS8AIShmvUxt80qlM26k/ujBIGtxewJ wixwEK/a9bwrcbY3qsiMGoPhlVoHBtb2meRMCfZJPOOiTYXXMiS1WUqc8nmBKyq6DH JBDX3BuhZTMGoiSxkUKBqyj5anrnTPz1kqAnsEuLo47Gxdz+F+2+wyYRb2sbyAN80o V8bJTFMrTIgNQ== From: Ard Biesheuvel To: linux-arm-kernel@lists.infradead.org Cc: Ard Biesheuvel , Will Deacon , Catalin Marinas , Marc Zyngier , Mark Rutland Subject: [PATCH v6 2/6] arm64: kernel: move identity map out of .text mapping Date: Tue, 29 Nov 2022 17:14:14 +0100 Message-Id: <20221129161418.1968319-3-ardb@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20221129161418.1968319-1-ardb@kernel.org> References: <20221129161418.1968319-1-ardb@kernel.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3476; i=ardb@kernel.org; h=from:subject; bh=U2iqnVkuhwtUu/qXPBf/2GNjjB270ekS914+aIpYPEc=; b=owEB7QES/pANAwAKAcNPIjmS2Y8kAcsmYgBjhi/ShyvMBIlSTQM481D7o9xscX5bWYIvJ8NQL2UN h7H6lBWJAbMEAAEKAB0WIQT72WJ8QGnJQhU3VynDTyI5ktmPJAUCY4Yv0gAKCRDDTyI5ktmPJCy0C/ 47GESyz9hlte82zWGZkKhoCwqE2ZfqsZ6iTSLe5JeU7/eF31/PhKrKYGtoHDknSjKII0f0LiopKh5x s5+d0sCteS2ClurgvR8LSr5w1Os72fUw9DSk7VFOOuJz0gA0uyoCWOcHjRi7zEohvvmsERu4Bdf5bi sVS8D8q65LZuf1nDUECj+CNgA00X7TjDZPp+V06m1oxgRE9KF+E2sql+E9hK9Mn/FS8I6t7Afk8w7e zTillIcbl14L2VMW8lYBKLVj7eCsUFXac4xa1DUA3HRq6XEYKwp8/W2UVajbIMn5jRefTgi5k7VS/H DNZ+1FrSTwGD8seFVpoyX1fN8q0XK/4vtoj2AYFXcMYMaYBhoI20Hptz4jM0NsF/A2pVHzx0vnlO2V Xujugiv1F/PRr2jDG6NqLeGprZ02+sCSH6BXDnA7MfpNQOR93RYVH3ktxLkA0Yi5j8Fcvnw4BF6dpc zO1elEHETz5gsfS1kBXlsLvQuhnPnnIPv8T8mArxA9OZc= X-Developer-Key: i=ardb@kernel.org; a=openpgp; fpr=F43D03328115A198C90016883D200E9CA6329909 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221129_081431_403026_5AFA0FF8 X-CRM114-Status: GOOD ( 14.65 ) 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 Reorganize the ID map slightly so that only code that is executed with the MMU off or via the 1:1 mapping remains. This allows us to move the identity map out of the .text segment, as it will no longer need executable permissions via the kernel mapping. Signed-off-by: Ard Biesheuvel --- arch/arm64/kernel/head.S | 28 +++++++++++--------- arch/arm64/kernel/vmlinux.lds.S | 2 +- arch/arm64/mm/proc.S | 2 -- 3 files changed, 16 insertions(+), 16 deletions(-) diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index c4e12d466a5f35f0..bec97aad092c2b43 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -543,19 +543,6 @@ SYM_INNER_LABEL(init_el2, SYM_L_LOCAL) eret SYM_FUNC_END(init_kernel_el) -/* - * Sets the __boot_cpu_mode flag depending on the CPU boot mode passed - * in w0. See arch/arm64/include/asm/virt.h for more info. - */ -SYM_FUNC_START_LOCAL(set_cpu_boot_mode_flag) - adr_l x1, __boot_cpu_mode - cmp w0, #BOOT_CPU_MODE_EL2 - b.ne 1f - add x1, x1, #4 -1: str w0, [x1] // Save CPU boot mode - ret -SYM_FUNC_END(set_cpu_boot_mode_flag) - /* * This provides a "holding pen" for platforms to hold all secondary * cores are held until we're ready for them to initialise. @@ -599,6 +586,7 @@ SYM_FUNC_START_LOCAL(secondary_startup) br x8 SYM_FUNC_END(secondary_startup) + .text SYM_FUNC_START_LOCAL(__secondary_switched) mov x0, x20 bl set_cpu_boot_mode_flag @@ -631,6 +619,19 @@ SYM_FUNC_START_LOCAL(__secondary_too_slow) b __secondary_too_slow SYM_FUNC_END(__secondary_too_slow) +/* + * Sets the __boot_cpu_mode flag depending on the CPU boot mode passed + * in w0. See arch/arm64/include/asm/virt.h for more info. + */ +SYM_FUNC_START_LOCAL(set_cpu_boot_mode_flag) + adr_l x1, __boot_cpu_mode + cmp w0, #BOOT_CPU_MODE_EL2 + b.ne 1f + add x1, x1, #4 +1: str w0, [x1] // Save CPU boot mode + ret +SYM_FUNC_END(set_cpu_boot_mode_flag) + /* * The booting CPU updates the failed status @__early_cpu_boot_status, * with MMU turned off. @@ -662,6 +663,7 @@ SYM_FUNC_END(__secondary_too_slow) * Checks if the selected granule size is supported by the CPU. * If it isn't, park the CPU */ + .section ".idmap.text","awx" SYM_FUNC_START(__enable_mmu) mrs x3, ID_AA64MMFR0_EL1 ubfx x3, x3, #ID_AA64MMFR0_EL1_TGRAN_SHIFT, 4 diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S index 4c13dafc98b8400f..407415a5163ab62f 100644 --- a/arch/arm64/kernel/vmlinux.lds.S +++ b/arch/arm64/kernel/vmlinux.lds.S @@ -179,7 +179,6 @@ SECTIONS LOCK_TEXT KPROBES_TEXT HYPERVISOR_TEXT - IDMAP_TEXT *(.gnu.warning) . = ALIGN(16); *(.got) /* Global offset table */ @@ -206,6 +205,7 @@ SECTIONS TRAMP_TEXT HIBERNATE_TEXT KEXEC_TEXT + IDMAP_TEXT . = ALIGN(PAGE_SIZE); } diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 066fa60b93d24827..91410f48809000a0 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -110,7 +110,6 @@ SYM_FUNC_END(cpu_do_suspend) * * x0: Address of context pointer */ - .pushsection ".idmap.text", "awx" SYM_FUNC_START(cpu_do_resume) ldp x2, x3, [x0] ldp x4, x5, [x0, #16] @@ -166,7 +165,6 @@ alternative_else_nop_endif isb ret SYM_FUNC_END(cpu_do_resume) - .popsection #endif .pushsection ".idmap.text", "awx"