From patchwork Sun Jun 25 15:28:41 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Song Shuai X-Patchwork-Id: 13292005 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 8C559C001B0 for ; Sun, 25 Jun 2023 15:29:17 +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=wEUe8EHanxSuNy9qPk1Cwe4Qx3s0REKyzBezY4tJfh4=; b=MLK/aebQ+gSgtX TJXGfBqzY6XPxpD3G25bXh91FEJG6wVXm29daSaYJIwTu9CqJwyVnpSFg6CxV2VOzDWWEMNVaHC7Q 39jf2xnU/XaaryECAc+MMIupHGmH8DtSmmaLexXRZOPeSg1p7ztx4FcpYUdLLZ7L68jDAlRs3j14G wvo/WjLYYNoYH6ZulO8F1bzv7EhKfYCwGEWdMjBRKJ/m0MdFL7YhuuWnPXRQPSC1JcssgVn+lJFhw 4NImDdkMq1IsipNwRiBabnShM/yBP6L2cNb5l1uhrn5V/cTkw73pIvllScf2sN0Mr+7SOlP/nDrtF 1lA+EBgsdhE3Jy97vjCw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qDRfo-008Dlu-3A; Sun, 25 Jun 2023 15:29:08 +0000 Received: from mail-pf1-x42c.google.com ([2607:f8b0:4864:20::42c]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qDRfm-008DlO-0K for linux-riscv@lists.infradead.org; Sun, 25 Jun 2023 15:29:07 +0000 Received: by mail-pf1-x42c.google.com with SMTP id d2e1a72fcca58-666ecf9a0ceso1072935b3a.2 for ; Sun, 25 Jun 2023 08:29:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1687706945; x=1690298945; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=J+WOYDIvLdd2NWRRa7PZxlpSE8oO3O/uffxAnfRWFTQ=; b=M/P1iEtEmWvR4gNy5Xi0GhWXMDNv1iAV49eqjRiWX/SAZBBrZ4s/wFnFIiajnvMR4U Cq1f9q3461N2I20MICOALV/oq3Y75DDRsxKW1LcN3YmT0VMpcBO192i2R/Tnray4uCLy qlguMhROpd4O4D0+1D39cIOsXUNWM1KGSHyLzylZe4sBdvfCgnfcCkK1IUM3FALO35Xj ESLoTOb/a6y+uu7bEc76FcwrssFtglHWWl1AsX9M1choSG87grsiErSmdrjGFyaW8M7I 5DGHbp/HmQuets+G9z+XnvhIyKsSjFiGne8NHRtO3iGjmISL0FDVioxo/FCmNlSMUbVn DwjQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1687706945; x=1690298945; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=J+WOYDIvLdd2NWRRa7PZxlpSE8oO3O/uffxAnfRWFTQ=; b=BS28Bbjlddki1rbjGK74fEFu4boGhmIOhjLty27d/3vKtjliUxx6ZkHhHikp57K5bM 0XOVCnZNmdPMcq6GyYPGTtRGE/wXoMotE/KUnu2SUvVheO9OEvoI3r+2Emh9D6XdO06P wFehprqdtnr2Ge5RBpuWUXf4im+Q+NlPp/yefcCroznHG1reBzbEcPLspI21WWXUCWfZ v38SARYl4WwBmWfhXKNl5J2FJHxGkxYWv+yoBRD2BI7huCcDv9QrDPQNR8nxIzPGyCIK cqo+7XZ/7iUNxTAGN+Las8LHfBO6cQDnOweyER3nSm7gIM21PYDzelKSspgIBpurnmsS EKCA== X-Gm-Message-State: AC+VfDwfnX8mZBlo82LttQ71UxA/W5q3PLNfJ3bXJl3qWzfLPOFk6Dns p4U6RdP75oiO14rZt/QMcOU= X-Google-Smtp-Source: ACHHUZ6mNVKRC/wAju5m3w9CI3n8kce2f6IYE2Xf6XLkhFJuxLumcPtstkhxjS+602cCUYMD2xfLoQ== X-Received: by 2002:a05:6a20:96db:b0:126:6c67:18bc with SMTP id hq27-20020a056a2096db00b001266c6718bcmr2001479pzc.38.1687706945039; Sun, 25 Jun 2023 08:29:05 -0700 (PDT) Received: from localhost.localdomain ([112.2.230.41]) by smtp.gmail.com with ESMTPSA id e19-20020a62aa13000000b0062bc045bf4fsm1710619pff.19.2023.06.25.08.28.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 25 Jun 2023 08:29:04 -0700 (PDT) From: Song Shuai To: songshuaishuai@tinylab.org Cc: ajones@ventanamicro.com, alexghiti@rivosinc.com, anshuman.khandual@arm.com, anup@brainfault.org, aou@eecs.berkeley.edu, arnd@arndb.de, conor.dooley@microchip.com, devicetree@vger.kernel.org, frowand.list@gmail.com, heiko@sntech.de, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, mpe@ellerman.id.au, palmer@dabbelt.com, panqinglin2020@iscas.ac.cn, paul.walmsley@sifive.com, robh+dt@kernel.org, rppt@kernel.org, samuel@sholland.org, xianting.tian@linux.alibaba.com Subject: [PATCH V1 3/3] Revert "riscv: Use PUD/P4D/PGD pages for the linear mapping" Date: Sun, 25 Jun 2023 23:28:41 +0800 Message-Id: <20230625152841.1280937-1-suagrfillet@gmail.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20230625140931.1266216-1-songshuaishuai@tinylab.org> References: <20230625140931.1266216-1-songshuaishuai@tinylab.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230625_082906_139991_955DB0CE X-CRM114-Status: GOOD ( 25.17 ) X-BeenThere: linux-riscv@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-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Song Shuai This reverts commit 3335068f87217ea59d08f462187dc856652eea15. This commit maps the PMP regions from some versions of OpenSbi in the linear mapping, that will lead to an access fault when doing hibernation[1] or some speculative accesses. The best_map_size() function from this commit doesn't check the virtual alignment before choosing a map size, that will cause a page fault[2]. We can let best_map_size() take the VA into consideration via commit 49a0a3731596 ("riscv: Check the virtual alignment before choosing a map size"), but that commit slows down the boot time and consumes some system memory when UEFI booting. This commit uses PUD/P4D/PGD pages for the linear mapping to improve the performance is marginal from a recent talk [3] from Mike Rapoport. OpenSbi had marked all the PMP-protected regions as "no-map" [4] to practice this talk. For all those reasons, let's revert this commit. [1] https://lore.kernel.org/linux-riscv/CAAYs2=gQvkhTeioMmqRDVGjdtNF_vhB+vm_1dHJxPNi75YDQ_Q@mail.gmail.com/ [2] https://lore.kernel.org/linux-riscv/tencent_7C3B580B47C1B17C16488EC1@qq.com/ [3] https://lwn.net/Articles/931406/ [4] https://github.com/riscv-software-src/opensbi/commit/8153b2622b08802cc542f30a1fcba407a5667ab9 Signed-off-by: Song Shuai --- arch/riscv/include/asm/page.h | 16 --------------- arch/riscv/mm/init.c | 38 ++++++----------------------------- arch/riscv/mm/physaddr.c | 16 --------------- drivers/of/fdt.c | 11 +++++----- 4 files changed, 11 insertions(+), 70 deletions(-) diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h index b55ba20903ec..21b346ab81c2 100644 --- a/arch/riscv/include/asm/page.h +++ b/arch/riscv/include/asm/page.h @@ -89,14 +89,6 @@ typedef struct page *pgtable_t; #define PTE_FMT "%08lx" #endif -#ifdef CONFIG_64BIT -/* - * We override this value as its generic definition uses __pa too early in - * the boot process (before kernel_map.va_pa_offset is set). - */ -#define MIN_MEMBLOCK_ADDR 0 -#endif - #ifdef CONFIG_MMU #define ARCH_PFN_OFFSET (PFN_DOWN((unsigned long)phys_ram_base)) #else @@ -128,11 +120,7 @@ extern phys_addr_t phys_ram_base; #define is_linear_mapping(x) \ ((x) >= PAGE_OFFSET && (!IS_ENABLED(CONFIG_64BIT) || (x) < PAGE_OFFSET + KERN_VIRT_SIZE)) -#ifndef CONFIG_DEBUG_VIRTUAL #define linear_mapping_pa_to_va(x) ((void *)((unsigned long)(x) + kernel_map.va_pa_offset)) -#else -void *linear_mapping_pa_to_va(unsigned long x); -#endif #define kernel_mapping_pa_to_va(y) ({ \ unsigned long _y = (unsigned long)(y); \ (IS_ENABLED(CONFIG_XIP_KERNEL) && _y < phys_ram_base) ? \ @@ -141,11 +129,7 @@ void *linear_mapping_pa_to_va(unsigned long x); }) #define __pa_to_va_nodebug(x) linear_mapping_pa_to_va(x) -#ifndef CONFIG_DEBUG_VIRTUAL #define linear_mapping_va_to_pa(x) ((unsigned long)(x) - kernel_map.va_pa_offset) -#else -phys_addr_t linear_mapping_va_to_pa(unsigned long x); -#endif #define kernel_mapping_va_to_pa(y) ({ \ unsigned long _y = (unsigned long)(y); \ (IS_ENABLED(CONFIG_XIP_KERNEL) && _y < kernel_map.virt_addr + XIP_OFFSET) ? \ diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 38c4b4d6b64f..4561781bcf60 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -216,14 +216,6 @@ static void __init setup_bootmem(void) phys_ram_end = memblock_end_of_DRAM(); if (!IS_ENABLED(CONFIG_XIP_KERNEL)) phys_ram_base = memblock_start_of_DRAM(); - - /* - * In 64-bit, any use of __va/__pa before this point is wrong as we - * did not know the start of DRAM before. - */ - if (IS_ENABLED(CONFIG_64BIT)) - kernel_map.va_pa_offset = PAGE_OFFSET - phys_ram_base; - /* * memblock allocator is not aware of the fact that last 4K bytes of * the addressable memory can not be mapped because of IS_ERR_VALUE @@ -662,16 +654,9 @@ void __init create_pgd_mapping(pgd_t *pgdp, static uintptr_t __init best_map_size(phys_addr_t base, phys_addr_t size) { - if (!(base & (PGDIR_SIZE - 1)) && size >= PGDIR_SIZE) - return PGDIR_SIZE; - - if (!(base & (P4D_SIZE - 1)) && size >= P4D_SIZE) - return P4D_SIZE; - - if (!(base & (PUD_SIZE - 1)) && size >= PUD_SIZE) - return PUD_SIZE; - - if (!(base & (PMD_SIZE - 1)) && size >= PMD_SIZE) + /* Upgrade to PMD_SIZE mappings whenever possible */ + base &= PMD_SIZE - 1; + if (!base && size >= PMD_SIZE) return PMD_SIZE; return PAGE_SIZE; @@ -1037,22 +1022,11 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) set_satp_mode(dtb_pa); #endif - /* - * In 64-bit, we defer the setup of va_pa_offset to setup_bootmem, - * where we have the system memory layout: this allows us to align - * the physical and virtual mappings and then make use of PUD/P4D/PGD - * for the linear mapping. This is only possible because the kernel - * mapping lies outside the linear mapping. - * In 32-bit however, as the kernel resides in the linear mapping, - * setup_vm_final can not change the mapping established here, - * otherwise the same kernel addresses would get mapped to different - * physical addresses (if the start of dram is different from the - * kernel physical address start). - */ - kernel_map.va_pa_offset = IS_ENABLED(CONFIG_64BIT) ? - 0UL : PAGE_OFFSET - kernel_map.phys_addr; + kernel_map.va_pa_offset = PAGE_OFFSET - kernel_map.phys_addr; kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr; + phys_ram_base = kernel_map.phys_addr; + /* * The default maximal physical memory size is KERN_VIRT_SIZE for 32-bit * kernel, whereas for 64-bit kernel, the end of the virtual address diff --git a/arch/riscv/mm/physaddr.c b/arch/riscv/mm/physaddr.c index 18706f457da7..9b18bda74154 100644 --- a/arch/riscv/mm/physaddr.c +++ b/arch/riscv/mm/physaddr.c @@ -33,19 +33,3 @@ phys_addr_t __phys_addr_symbol(unsigned long x) return __va_to_pa_nodebug(x); } EXPORT_SYMBOL(__phys_addr_symbol); - -phys_addr_t linear_mapping_va_to_pa(unsigned long x) -{ - BUG_ON(!kernel_map.va_pa_offset); - - return ((unsigned long)(x) - kernel_map.va_pa_offset); -} -EXPORT_SYMBOL(linear_mapping_va_to_pa); - -void *linear_mapping_pa_to_va(unsigned long x) -{ - BUG_ON(!kernel_map.va_pa_offset); - - return ((void *)((unsigned long)(x) + kernel_map.va_pa_offset)); -} -EXPORT_SYMBOL(linear_mapping_pa_to_va); diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c index bf502ba8da95..c28aedd7ae1f 100644 --- a/drivers/of/fdt.c +++ b/drivers/of/fdt.c @@ -888,13 +888,12 @@ const void * __init of_flat_dt_match_machine(const void *default_match, static void __early_init_dt_declare_initrd(unsigned long start, unsigned long end) { - /* - * __va() is not yet available this early on some platforms. In that - * case, the platform uses phys_initrd_start/phys_initrd_size instead - * and does the VA conversion itself. + /* ARM64 would cause a BUG to occur here when CONFIG_DEBUG_VM is + * enabled since __va() is called too early. ARM64 does make use + * of phys_initrd_start/phys_initrd_size so we can skip this + * conversion. */ - if (!IS_ENABLED(CONFIG_ARM64) && - !(IS_ENABLED(CONFIG_RISCV) && IS_ENABLED(CONFIG_64BIT))) { + if (!IS_ENABLED(CONFIG_ARM64)) { initrd_start = (unsigned long)__va(start); initrd_end = (unsigned long)__va(end); initrd_below_start_ok = 1;