From patchwork Fri Mar 18 17:48:32 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Morse X-Patchwork-Id: 553004 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 69B27C433F5 for ; Fri, 18 Mar 2022 17:49:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239871AbiCRRvM (ORCPT ); Fri, 18 Mar 2022 13:51:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38324 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239842AbiCRRvH (ORCPT ); Fri, 18 Mar 2022 13:51:07 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 316A2189A37; Fri, 18 Mar 2022 10:49:44 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0E35D1515; Fri, 18 Mar 2022 10:49:44 -0700 (PDT) Received: from eglon.cambridge.arm.com (eglon.cambridge.arm.com [10.1.196.218]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6292F3F7B4; Fri, 18 Mar 2022 10:49:43 -0700 (PDT) From: James Morse To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, james.morse@arm.com, catalin.marinas@arm.com Subject: [stable:PATCH v4.19.235 12/22] arm64: entry: Allow the trampoline text to occupy multiple pages Date: Fri, 18 Mar 2022 17:48:32 +0000 Message-Id: <20220318174842.2321061-13-james.morse@arm.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220318174842.2321061-1-james.morse@arm.com> References: <20220318174842.2321061-1-james.morse@arm.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org commit a9c406e6462ff14956d690de7bbe5131a5677dc9 upstream. Adding a second set of vectors to .entry.tramp.text will make it larger than a single 4K page. Allow the trampoline text to occupy up to three pages by adding two more fixmap slots. Previous changes to tramp_valias allowed it to reach beyond a single page. Reviewed-by: Catalin Marinas Signed-off-by: James Morse --- arch/arm64/include/asm/fixmap.h | 6 ++++-- arch/arm64/include/asm/sections.h | 5 +++++ arch/arm64/kernel/entry.S | 2 +- arch/arm64/kernel/vmlinux.lds.S | 2 +- arch/arm64/mm/mmu.c | 12 +++++++++--- 5 files changed, 20 insertions(+), 7 deletions(-) diff --git a/arch/arm64/include/asm/fixmap.h b/arch/arm64/include/asm/fixmap.h index c0cfc6d3bf9f..3c962ef081f8 100644 --- a/arch/arm64/include/asm/fixmap.h +++ b/arch/arm64/include/asm/fixmap.h @@ -59,9 +59,11 @@ enum fixed_addresses { #endif /* CONFIG_ACPI_APEI_GHES */ #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 - FIX_ENTRY_TRAMP_TEXT, + FIX_ENTRY_TRAMP_TEXT3, + FIX_ENTRY_TRAMP_TEXT2, + FIX_ENTRY_TRAMP_TEXT1, FIX_ENTRY_TRAMP_DATA, -#define TRAMP_VALIAS (__fix_to_virt(FIX_ENTRY_TRAMP_TEXT)) +#define TRAMP_VALIAS (__fix_to_virt(FIX_ENTRY_TRAMP_TEXT1)) #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */ __end_of_permanent_fixed_addresses, diff --git a/arch/arm64/include/asm/sections.h b/arch/arm64/include/asm/sections.h index caab039d6305..8d3f1eab58e0 100644 --- a/arch/arm64/include/asm/sections.h +++ b/arch/arm64/include/asm/sections.h @@ -30,4 +30,9 @@ extern char __irqentry_text_start[], __irqentry_text_end[]; extern char __mmuoff_data_start[], __mmuoff_data_end[]; extern char __entry_tramp_text_start[], __entry_tramp_text_end[]; +static inline size_t entry_tramp_text_size(void) +{ + return __entry_tramp_text_end - __entry_tramp_text_start; +} + #endif /* __ASM_SECTIONS_H */ diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index 50843161607e..22d39c941a6d 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -966,7 +966,7 @@ alternative_else_nop_endif .endm .macro tramp_data_page dst - adr \dst, .entry.tramp.text + adr_l \dst, .entry.tramp.text sub \dst, \dst, PAGE_SIZE .endm diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S index 69e7c8d4a00f..370089455d38 100644 --- a/arch/arm64/kernel/vmlinux.lds.S +++ b/arch/arm64/kernel/vmlinux.lds.S @@ -259,7 +259,7 @@ ASSERT(__hibernate_exit_text_end - (__hibernate_exit_text_start & ~(SZ_4K - 1)) <= SZ_4K, "Hibernate exit text too big or misaligned") #endif #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 -ASSERT((__entry_tramp_text_end - __entry_tramp_text_start) == PAGE_SIZE, +ASSERT((__entry_tramp_text_end - __entry_tramp_text_start) <= 3*PAGE_SIZE, "Entry trampoline text too big") #endif /* diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 0fa558176fb1..b0a83dbed2dc 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -541,6 +541,8 @@ early_param("rodata", parse_rodata); #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 static int __init map_entry_trampoline(void) { + int i; + pgprot_t prot = rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC; phys_addr_t pa_start = __pa_symbol(__entry_tramp_text_start); @@ -549,11 +551,15 @@ static int __init map_entry_trampoline(void) /* Map only the text into the trampoline page table */ memset(tramp_pg_dir, 0, PGD_SIZE); - __create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS, PAGE_SIZE, - prot, pgd_pgtable_alloc, 0); + __create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS, + entry_tramp_text_size(), prot, pgd_pgtable_alloc, + 0); /* Map both the text and data into the kernel page table */ - __set_fixmap(FIX_ENTRY_TRAMP_TEXT, pa_start, prot); + for (i = 0; i < DIV_ROUND_UP(entry_tramp_text_size(), PAGE_SIZE); i++) + __set_fixmap(FIX_ENTRY_TRAMP_TEXT1 - i, + pa_start + i * PAGE_SIZE, prot); + if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) { extern char __entry_tramp_data_start[];