From patchwork Tue Mar 7 14:04:49 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 13163775 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 40ED5C6FD1A for ; Tue, 7 Mar 2023 14:34:28 +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=fDK6TIHciBBhYxKJWNE3euA8XuqzaKI5EBcqZOX5RM4=; b=eerlTHkX6F6qRO cbuf8xNxgPGt5a1miXWsBso6Jygk+uYUMBe5Jj6aLsfioxroRDJTvhDg0zFZWrmPqU2v5nOSxFABa VQ8mqQspvis/D+T2cf8pFV4lUjEd3t5R2/EiCuGqaQYSyP8WpT6UKeJm9GBg7rqNiOKkCXRHwWodL IDKlceO9EalTpar9QZijkj3WVb21shBcslyI/2zQifcRFhacW8NSV9jPFwJDfduH6erKBxA/YOswJ dS5S5dubyDodDrUEa7OHtqDF1FyuwCB8p2FGIYOa83J3jauyfIFKDeo5NZH2Rdk0MMfJjsUAsonV3 YLLLSAAonPbBi3cOY8Ng==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pZYNQ-000pdE-K4; Tue, 07 Mar 2023 14:33:16 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1pZXyi-000eQW-95 for linux-arm-kernel@lists.infradead.org; Tue, 07 Mar 2023 14:07:45 +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 dfw.source.kernel.org (Postfix) with ESMTPS id C94E861455; Tue, 7 Mar 2023 14:07:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 442E9C433A1; Tue, 7 Mar 2023 14:07:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1678198063; bh=LGPwuGUBE9+D2Ri4mVTa9KzwPrnmKSHtWXBpjrEGvfU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RwzOzBuuV/wfG5j8QfOfX32RG0eTjM+i2oreD47PIfD3xfe6B8MWngtR5XRC0GzhU 5B6cc0APiUj0c+EvQfL1dcFT3tOVcKBJYt3xBd1LA5qKWqjel9ddOwaK9TSr8dlq9S bsQ3ieraqDDj+gClYHPuEXhJ+65Ka1BJ+jAIgphsLHMYA8v1ABeGYMWCoL0H3YLJ+E pphixn4kEPbe/FsBnLjFah7Q4mhll9rULdSHzJhLssrLHSGIe8OZgvk4udC32738SE Gg84NPJJAs94/bytiFf1AoJ+9oQni2qFHObKbvekDheKuCwdKbb5vkqWlnU3hMz6w+ GSwxrNUkJcohA== From: Ard Biesheuvel To: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, Ard Biesheuvel , Catalin Marinas , Will Deacon , Marc Zyngier , Mark Rutland , Ryan Roberts , Anshuman Khandual , Kees Cook Subject: [PATCH v3 27/60] arm64: head: Run feature override detection before mapping the kernel Date: Tue, 7 Mar 2023 15:04:49 +0100 Message-Id: <20230307140522.2311461-28-ardb@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230307140522.2311461-1-ardb@kernel.org> References: <20230307140522.2311461-1-ardb@kernel.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2825; i=ardb@kernel.org; h=from:subject; bh=LGPwuGUBE9+D2Ri4mVTa9KzwPrnmKSHtWXBpjrEGvfU=; b=owGbwMvMwCFmkMcZplerG8N4Wi2JIYXdxenLuW+3y64XPmd4dOOZjIxXtH5B38riC5cW7E5d2 HJqu9zEjlIWBjEOBlkxRRaB2X/f7Tw9UarWeZYszBxWJpAhDFycAjCRlfMY/qd5fVJ2i2BfrprU flVk2TPP4nqFYv73WeI1mbu/zDo7M53hv7vjEWPNV49u3VqyxGqfzLQvKRcjL7fvvH9USoevqpN RiBMA 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-20230307_060744_434125_1CDEB99F X-CRM114-Status: GOOD ( 15.07 ) 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 To permit the feature overrides to be taken into account before the KASLR init code runs and the kernel mapping is created, move the detection code to an earlier stage in the boot. In a subsequent patch, this will be taken advantage of by merging the preliminary and permanent mappings of the kernel text and data into a single one that gets created and relocated before start_kernel() is called. Signed-off-by: Ard Biesheuvel --- arch/arm64/kernel/head.S | 17 +++++++++-------- arch/arm64/kernel/vmlinux.lds.S | 4 +--- 2 files changed, 10 insertions(+), 11 deletions(-) diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index ade0cb99c8a83a3d..0a345898a12939af 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -375,9 +375,9 @@ SYM_FUNC_START_LOCAL(create_idmap) map_memory x0, x1, x3, x6, x7, x3, IDMAP_PGD_ORDER, x10, x11, x12, x13, x14, EXTRA_SHIFT - /* Remap BSS and the kernel page tables r/w in the ID map */ + /* Remap [.init].data, BSS and the kernel page tables r/w in the ID map */ adrp x1, _text - adrp x2, __bss_start + adrp x2, __initdata_begin adrp x3, _end bic x4, x2, #SWAPPER_BLOCK_SIZE - 1 mov x5, SWAPPER_RW_MMUFLAGS @@ -491,9 +491,6 @@ SYM_FUNC_START_LOCAL(__primary_switched) #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) bl kasan_early_init #endif - mov x0, x20 // pass the full boot status - mov x1, x22 // pass the low FDT mapping - bl __pi_init_feature_override // Parse cpu feature overrides #ifdef CONFIG_UNWIND_PATCH_PAC_INTO_SCS bl scs_patch_vmlinux #endif @@ -770,12 +767,16 @@ SYM_FUNC_START_LOCAL(__primary_switch) bl __pi_memset dsb ishst // Make zero page visible to PTW -#ifdef CONFIG_RELOCATABLE - adrp x23, KERNEL_START - and x23, x23, MIN_KIMG_ALIGN - 1 adrp x1, early_init_stack mov sp, x1 mov x29, xzr + mov x0, x20 // pass the full boot status + mov x1, x22 // pass the low FDT mapping + bl __pi_init_feature_override // Parse cpu feature overrides + +#ifdef CONFIG_RELOCATABLE + adrp x23, KERNEL_START + and x23, x23, MIN_KIMG_ALIGN - 1 #ifdef CONFIG_RANDOMIZE_BASE mov x0, x22 bl __pi_kaslr_early_init diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S index ec24b1e70d606ec8..6c79ad2945749260 100644 --- a/arch/arm64/kernel/vmlinux.lds.S +++ b/arch/arm64/kernel/vmlinux.lds.S @@ -318,10 +318,8 @@ SECTIONS init_pg_dir = .; . += INIT_DIR_SIZE; init_pg_end = .; -#ifdef CONFIG_RELOCATABLE - . += SZ_4K; /* stack for the early relocation code */ + . += SZ_4K; /* stack for the early C runtime */ early_init_stack = .; -#endif . = ALIGN(SEGMENT_ALIGN); __pecoff_data_size = ABSOLUTE(. - __initdata_begin);