From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7FE34C433DB for ; Tue, 26 Jan 2021 12:29:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 56AA423109 for ; Tue, 26 Jan 2021 12:29:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404348AbhAZKoh (ORCPT ); Tue, 26 Jan 2021 05:44:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53992 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732105AbhAZCF4 (ORCPT ); Mon, 25 Jan 2021 21:05:56 -0500 Received: from mail-qt1-x830.google.com (mail-qt1-x830.google.com [IPv6:2607:f8b0:4864:20::830]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A2812C061794 for ; Mon, 25 Jan 2021 16:21:24 -0800 (PST) Received: by mail-qt1-x830.google.com with SMTP id r9so11101628qtp.11 for ; Mon, 25 Jan 2021 16:21:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-language:content-transfer-encoding; bh=SfDON/fUCN5vFNGlJEHUAmiQAgyTytVUuGLA7le4ocM=; b=mSZW3JK/Da4DVr3IZcAFoxoVE7UG+SuxF8iBsqITb47a5eBC8PyfK2V6JQY2utEpAT JG6Gv2A0SUZQQYOrdvzzA+Yc49fE61MVHXktyqWI9s/rhUBoWjAuTX94iPtfuZ8F67pn DQt9L1KP+N3jt1bLc5CImvPJYQQi0FBZPpjnLBGPQIY+VhqnZcdql/JfIrubItmNTcIg kV3+ap9sa4XCdE5tSszIb3KE0muhNP65czQrkiYVGSjvYoYmI8/WUAKPFcFX9vOSuYja 2kxjh+Vs183WUO1vQquTmxnAeQUPpgsQX91bjMG5U3UbXpRknd6Erz7lA2WP3yX30rea +XEA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=SfDON/fUCN5vFNGlJEHUAmiQAgyTytVUuGLA7le4ocM=; b=PhUz9VwcY9M2/sesEODQy+N4H7tIPctwu6wRxRwGjI9c9KOxhd6EAF2JZ1E3ZmcwSh am+66VFPZC/fhp7xRmyRceM3KjmkRbHPupzqhZgCgp9oJSMkPrX6OWkEUCVQYbwNm9r2 beka6cnYBW1yudA0UUL4FIePzW4WYj8E1urLDNvyKVhPRFIM2ryX4flbGp282iuyVMhM 7HQiZiVxgByLLaPfzLiU6yPB7uRPeeWFnUkicgL1SeZBo6UTUMUQYpY1GkmRTGGOF7tS jru2OtRzrz/9/1Qss+sNu/NZ56EXUiLXezZZcxw9k5V3aLtQ+ersA8e2Pduw3gPRCXDe v/Rg== X-Gm-Message-State: AOAM533Lpw/NDdDbvXZtssARgWndR0lsup8qc4YoBNEJXlkaF8HDTOqt tiHsTNSG3zMi6k2rS+VO6ZP8lg== X-Google-Smtp-Source: ABdhPJySDX+/2vGo1QOlrTbm8VvGmucVBi2YsKjIRMCnCSaEx7I60Syypvewljmz+IN5nmbdwYExgw== X-Received: by 2002:ac8:6d34:: with SMTP id r20mr2969876qtu.299.1611620483853; Mon, 25 Jan 2021 16:21:23 -0800 (PST) Received: from [192.168.1.195] (c-73-69-118-222.hsd1.nh.comcast.net. [73.69.118.222]) by smtp.gmail.com with ESMTPSA id d1sm13115293qkf.102.2021.01.25.16.21.22 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 25 Jan 2021 16:21:23 -0800 (PST) Subject: Re: [PATCH v10 16/18] arm64: kexec: configure trans_pgd page table for kexec To: jmorris@namei.org, sashal@kernel.org, ebiederm@xmission.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, corbet@lwn.net, catalin.marinas@arm.com, will@kernel.org, linux-arm-kernel@lists.infradead.org, maz@kernel.org, james.morse@arm.com, vladimir.murzin@arm.com, matthias.bgg@gmail.com, linux-mm@kvack.org, mark.rutland@arm.com, steve.capper@arm.com, rfontana@redhat.com, tglx@linutronix.de, selindag@gmail.com, tyhicks@linux.microsoft.com References: <20210125191923.1060122-1-pasha.tatashin@soleen.com> <20210125191923.1060122-17-pasha.tatashin@soleen.com> From: Pavel Tatashin Message-ID: Date: Mon, 25 Jan 2021 19:21:22 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20210125191923.1060122-17-pasha.tatashin@soleen.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I forgot to make changes to arch/arm64/Kconfig. The correct patch is below. --- >From a2bc374320d7c7efd3c40644ad3d6d59a024b301 Mon Sep 17 00:00:00 2001 From: Pavel Tatashin Date: Mon, 29 Jul 2019 21:24:25 -0400 Subject: [PATCH v10 16/18] arm64: kexec: configure trans_pgd page table for kexec Configure a page table located in kexec-safe memory that has the following mappings: 1. identity mapping for text of relocation function with executable permission. 2. va mappings for all source ranges 3. va mappings for all destination ranges. Signed-off-by: Pavel Tatashin --- arch/arm64/Kconfig | 2 +- arch/arm64/include/asm/kexec.h | 12 ++++ arch/arm64/kernel/asm-offsets.c | 6 ++ arch/arm64/kernel/machine_kexec.c | 91 ++++++++++++++++++++++++++++++- 4 files changed, 109 insertions(+), 2 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index fc0ed9d6e011..440abd0c0ee1 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1134,7 +1134,7 @@ config CRASH_DUMP config TRANS_TABLE def_bool y - depends on HIBERNATION + depends on HIBERNATION || KEXEC_CORE config XEN_DOM0 def_bool y diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h index b96d8a6aac80..049cde429b1b 100644 --- a/arch/arm64/include/asm/kexec.h +++ b/arch/arm64/include/asm/kexec.h @@ -105,6 +105,12 @@ extern const char arm64_kexec_el2_vectors[]; * el2_vector If present means that relocation routine will go to EL1 * from EL2 to do the copy, and then back to EL2 to do the jump * to new world. + * trans_ttbr0 idmap for relocation function and its argument + * trans_ttbr1 map for source/destination addresses. + * trans_t0sz t0sz for idmap page in trans_ttbr0 + * src_addr start address for source pages. + * dst_addr start address for destination pages. + * copy_len Number of bytes that need to be copied */ struct kern_reloc_arg { phys_addr_t head; @@ -114,6 +120,12 @@ struct kern_reloc_arg { phys_addr_t kern_arg2; phys_addr_t kern_arg3; phys_addr_t el2_vector; + phys_addr_t trans_ttbr0; + phys_addr_t trans_ttbr1; + unsigned long trans_t0sz; + unsigned long src_addr; + unsigned long dst_addr; + unsigned long copy_len; }; #define ARCH_HAS_KIMAGE_ARCH diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index 8a9475be1b62..06278611451d 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -160,6 +160,12 @@ int main(void) DEFINE(KEXEC_KRELOC_KERN_ARG2, offsetof(struct kern_reloc_arg, kern_arg2)); DEFINE(KEXEC_KRELOC_KERN_ARG3, offsetof(struct kern_reloc_arg, kern_arg3)); DEFINE(KEXEC_KRELOC_EL2_VECTOR, offsetof(struct kern_reloc_arg, el2_vector)); + DEFINE(KEXEC_KRELOC_TRANS_TTBR0, offsetof(struct kern_reloc_arg, trans_ttbr0)); + DEFINE(KEXEC_KRELOC_TRANS_TTBR1, offsetof(struct kern_reloc_arg, trans_ttbr1)); + DEFINE(KEXEC_KRELOC_TRANS_T0SZ, offsetof(struct kern_reloc_arg, trans_t0sz)); + DEFINE(KEXEC_KRELOC_SRC_ADDR, offsetof(struct kern_reloc_arg, src_addr)); + DEFINE(KEXEC_KRELOC_DST_ADDR, offsetof(struct kern_reloc_arg, dst_addr)); + DEFINE(KEXEC_KRELOC_COPY_LEN, offsetof(struct kern_reloc_arg, copy_len)); #endif return 0; } diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c index 41d1e3ca13f8..dc1b7e5a54fb 100644 --- a/arch/arm64/kernel/machine_kexec.c +++ b/arch/arm64/kernel/machine_kexec.c @@ -21,6 +21,7 @@ #include #include #include +#include #include "cpu-reset.h" @@ -71,11 +72,91 @@ static void *kexec_page_alloc(void *arg) return page_address(page); } +/* + * Map source segments starting from src_va, and map destination + * segments starting from dst_va, and return size of copy in + * *copy_len argument. + * Relocation function essentially needs to do: + * memcpy(dst_va, src_va, copy_len); + */ +static int map_segments(struct kimage *kimage, pgd_t *pgdp, + struct trans_pgd_info *info, + unsigned long src_va, + unsigned long dst_va, + unsigned long *copy_len) +{ + unsigned long *ptr = 0; + unsigned long dest = 0; + unsigned long len = 0; + unsigned long entry, addr; + int rc; + + for (entry = kimage->head; !(entry & IND_DONE); entry = *ptr++) { + addr = entry & PAGE_MASK; + + switch (entry & IND_FLAGS) { + case IND_DESTINATION: + dest = addr; + break; + case IND_INDIRECTION: + ptr = __va(addr); + if (rc) + return rc; + break; + case IND_SOURCE: + rc = trans_pgd_map_page(info, pgdp, __va(addr), + src_va, PAGE_KERNEL); + if (rc) + return rc; + rc = trans_pgd_map_page(info, pgdp, __va(dest), + dst_va, PAGE_KERNEL); + if (rc) + return rc; + dest += PAGE_SIZE; + src_va += PAGE_SIZE; + dst_va += PAGE_SIZE; + len += PAGE_SIZE; + } + } + *copy_len = len; + + return 0; +} + +static int mmu_relocate_setup(struct kimage *kimage, void *reloc_code, + struct kern_reloc_arg *kern_reloc_arg) +{ + struct trans_pgd_info info = { + .trans_alloc_page = kexec_page_alloc, + .trans_alloc_arg = kimage, + }; + pgd_t *trans_pgd = kexec_page_alloc(kimage); + int rc; + + if (!trans_pgd) + return -ENOMEM; + + /* idmap relocation function */ + rc = trans_pgd_idmap_page(&info, &kern_reloc_arg->trans_ttbr0, + &kern_reloc_arg->trans_t0sz, reloc_code); + if (rc) + return rc; + + kern_reloc_arg->src_addr = _PAGE_OFFSET(VA_BITS_MIN); + kern_reloc_arg->dst_addr = _PAGE_OFFSET(VA_BITS_MIN - 1); + kern_reloc_arg->trans_ttbr1 = phys_to_ttbr(__pa(trans_pgd)); + + rc = map_segments(kimage, trans_pgd, &info, kern_reloc_arg->src_addr, + kern_reloc_arg->dst_addr, &kern_reloc_arg->copy_len); + return rc; +} + int machine_kexec_post_load(struct kimage *kimage) { void *reloc_code = page_to_virt(kimage->control_code_page); struct kern_reloc_arg *kern_reloc_arg = kexec_page_alloc(kimage); long func_offset, vector_offset, reloc_size; + int rc = 0; if (!kern_reloc_arg) return -ENOMEM; @@ -95,6 +176,14 @@ int machine_kexec_post_load(struct kimage *kimage) if (is_hyp_mode_available() && !is_kernel_in_hyp_mode()) kern_reloc_arg->el2_vector = __pa(reloc_code) + vector_offset; + /* + * If relocation is not needed, we do not need to enable MMU in + * relocation routine, therefore do not create page tables for + * scenarios such as crash kernel + */ + if (!(kimage->head & IND_DONE)) + rc = mmu_relocate_setup(kimage, reloc_code, kern_reloc_arg); + kexec_image_info(kimage); /* Flush the reloc_code in preparation for its execution. */ @@ -103,7 +192,7 @@ int machine_kexec_post_load(struct kimage *kimage) reloc_size); __flush_dcache_area(kern_reloc_arg, sizeof(struct kern_reloc_arg)); - return 0; + return rc; } /** -- 2.25.1 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 716DAC433DB for ; Tue, 26 Jan 2021 00:22:52 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 29CA8230FE for ; Tue, 26 Jan 2021 00:22:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 29CA8230FE Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=soleen.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe :List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From:References:To:Subject: Reply-To:Cc:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=dkJGSTTyMnO4pcbkO1/dMDPxEBjwDyeGsnHYnBkiT5o=; b=YPqDp7FQh5kxbhQKw17D/H665L Bhtx0ESLjYQd5JpF/cGvLXGKZ7rZYDuoPzgp9VP9EfH7izddS4R+vCZepOqYQU083g5VFgwIkcFer BEb1MV5OEgMTXOsrby13p7NOCuw5cMEjQvGBFjcOoQwmDTClYo3QH0pdSfiOUu30xFbqwP6q4qB40 oKKE2FMhsPvXqqohKcgmdc4um8R89MhX00fBBQWsmbA3WurJwQ1riVxFTL18MMkNC1pPdtGUutHhy Guqs8t9LIetCkomX2mXmW9rP1CGQhYB4DYd7I+wCg9NVUSzM80HfbAaFB2X2QmyMjGIEBaOwycLvv YqxdofaQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l4C6r-0004vl-EJ; Tue, 26 Jan 2021 00:21:29 +0000 Received: from mail-qt1-x836.google.com ([2607:f8b0:4864:20::836]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l4C6o-0004v3-21 for linux-arm-kernel@lists.infradead.org; Tue, 26 Jan 2021 00:21:27 +0000 Received: by mail-qt1-x836.google.com with SMTP id l23so8642511qtq.13 for ; Mon, 25 Jan 2021 16:21:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-language:content-transfer-encoding; bh=SfDON/fUCN5vFNGlJEHUAmiQAgyTytVUuGLA7le4ocM=; b=mSZW3JK/Da4DVr3IZcAFoxoVE7UG+SuxF8iBsqITb47a5eBC8PyfK2V6JQY2utEpAT JG6Gv2A0SUZQQYOrdvzzA+Yc49fE61MVHXktyqWI9s/rhUBoWjAuTX94iPtfuZ8F67pn DQt9L1KP+N3jt1bLc5CImvPJYQQi0FBZPpjnLBGPQIY+VhqnZcdql/JfIrubItmNTcIg kV3+ap9sa4XCdE5tSszIb3KE0muhNP65czQrkiYVGSjvYoYmI8/WUAKPFcFX9vOSuYja 2kxjh+Vs183WUO1vQquTmxnAeQUPpgsQX91bjMG5U3UbXpRknd6Erz7lA2WP3yX30rea +XEA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=SfDON/fUCN5vFNGlJEHUAmiQAgyTytVUuGLA7le4ocM=; b=gZUySsQJURbaGiwpyRIVGwQWf/VV8ddkKnZ8f+CTnO5rPPUy3QfzDJu5z1YCsq2JUF XvDW1AOKarQlw14wpM1ypUFAY2KNJoGOreMTcjgCBZ9ML84srxI9NwkUpmIBF3+25zbs DYNHT+/8Q7fy7Xpf3xF6Uh1uYh5jpBfMN/Ns5RCsqSjDHHUadr5s0e/w4AUbEBOqlnNz LTF1nnJ25Wy/JD6L41ybhxwiMydYjK8S0DL7ko2CK9ThUFSuT5377C6+UW/XVqjw/5Vn NYyHYusuwlX/shTEbA12cwLRo34WlRi9GMZ9Dk3WxEygMRsqRBhI+NrCMMV92P2g3FiZ ypHA== X-Gm-Message-State: AOAM530cuItei2GRZhTXTZACVTX0bewS6C4ApGv5VMTMVMSXo9dVqVBE 7KwSJGSfyB6jDIc+RdcIlXe12w== X-Google-Smtp-Source: ABdhPJySDX+/2vGo1QOlrTbm8VvGmucVBi2YsKjIRMCnCSaEx7I60Syypvewljmz+IN5nmbdwYExgw== X-Received: by 2002:ac8:6d34:: with SMTP id r20mr2969876qtu.299.1611620483853; Mon, 25 Jan 2021 16:21:23 -0800 (PST) Received: from [192.168.1.195] (c-73-69-118-222.hsd1.nh.comcast.net. [73.69.118.222]) by smtp.gmail.com with ESMTPSA id d1sm13115293qkf.102.2021.01.25.16.21.22 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 25 Jan 2021 16:21:23 -0800 (PST) Subject: Re: [PATCH v10 16/18] arm64: kexec: configure trans_pgd page table for kexec To: jmorris@namei.org, sashal@kernel.org, ebiederm@xmission.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, corbet@lwn.net, catalin.marinas@arm.com, will@kernel.org, linux-arm-kernel@lists.infradead.org, maz@kernel.org, james.morse@arm.com, vladimir.murzin@arm.com, matthias.bgg@gmail.com, linux-mm@kvack.org, mark.rutland@arm.com, steve.capper@arm.com, rfontana@redhat.com, tglx@linutronix.de, selindag@gmail.com, tyhicks@linux.microsoft.com References: <20210125191923.1060122-1-pasha.tatashin@soleen.com> <20210125191923.1060122-17-pasha.tatashin@soleen.com> From: Pavel Tatashin Message-ID: Date: Mon, 25 Jan 2021 19:21:22 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20210125191923.1060122-17-pasha.tatashin@soleen.com> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210125_192126_283371_FC036491 X-CRM114-Status: GOOD ( 25.74 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org I forgot to make changes to arch/arm64/Kconfig. The correct patch is below. --- >From a2bc374320d7c7efd3c40644ad3d6d59a024b301 Mon Sep 17 00:00:00 2001 From: Pavel Tatashin Date: Mon, 29 Jul 2019 21:24:25 -0400 Subject: [PATCH v10 16/18] arm64: kexec: configure trans_pgd page table for kexec Configure a page table located in kexec-safe memory that has the following mappings: 1. identity mapping for text of relocation function with executable permission. 2. va mappings for all source ranges 3. va mappings for all destination ranges. Signed-off-by: Pavel Tatashin --- arch/arm64/Kconfig | 2 +- arch/arm64/include/asm/kexec.h | 12 ++++ arch/arm64/kernel/asm-offsets.c | 6 ++ arch/arm64/kernel/machine_kexec.c | 91 ++++++++++++++++++++++++++++++- 4 files changed, 109 insertions(+), 2 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index fc0ed9d6e011..440abd0c0ee1 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1134,7 +1134,7 @@ config CRASH_DUMP config TRANS_TABLE def_bool y - depends on HIBERNATION + depends on HIBERNATION || KEXEC_CORE config XEN_DOM0 def_bool y diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h index b96d8a6aac80..049cde429b1b 100644 --- a/arch/arm64/include/asm/kexec.h +++ b/arch/arm64/include/asm/kexec.h @@ -105,6 +105,12 @@ extern const char arm64_kexec_el2_vectors[]; * el2_vector If present means that relocation routine will go to EL1 * from EL2 to do the copy, and then back to EL2 to do the jump * to new world. + * trans_ttbr0 idmap for relocation function and its argument + * trans_ttbr1 map for source/destination addresses. + * trans_t0sz t0sz for idmap page in trans_ttbr0 + * src_addr start address for source pages. + * dst_addr start address for destination pages. + * copy_len Number of bytes that need to be copied */ struct kern_reloc_arg { phys_addr_t head; @@ -114,6 +120,12 @@ struct kern_reloc_arg { phys_addr_t kern_arg2; phys_addr_t kern_arg3; phys_addr_t el2_vector; + phys_addr_t trans_ttbr0; + phys_addr_t trans_ttbr1; + unsigned long trans_t0sz; + unsigned long src_addr; + unsigned long dst_addr; + unsigned long copy_len; }; #define ARCH_HAS_KIMAGE_ARCH diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index 8a9475be1b62..06278611451d 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -160,6 +160,12 @@ int main(void) DEFINE(KEXEC_KRELOC_KERN_ARG2, offsetof(struct kern_reloc_arg, kern_arg2)); DEFINE(KEXEC_KRELOC_KERN_ARG3, offsetof(struct kern_reloc_arg, kern_arg3)); DEFINE(KEXEC_KRELOC_EL2_VECTOR, offsetof(struct kern_reloc_arg, el2_vector)); + DEFINE(KEXEC_KRELOC_TRANS_TTBR0, offsetof(struct kern_reloc_arg, trans_ttbr0)); + DEFINE(KEXEC_KRELOC_TRANS_TTBR1, offsetof(struct kern_reloc_arg, trans_ttbr1)); + DEFINE(KEXEC_KRELOC_TRANS_T0SZ, offsetof(struct kern_reloc_arg, trans_t0sz)); + DEFINE(KEXEC_KRELOC_SRC_ADDR, offsetof(struct kern_reloc_arg, src_addr)); + DEFINE(KEXEC_KRELOC_DST_ADDR, offsetof(struct kern_reloc_arg, dst_addr)); + DEFINE(KEXEC_KRELOC_COPY_LEN, offsetof(struct kern_reloc_arg, copy_len)); #endif return 0; } diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c index 41d1e3ca13f8..dc1b7e5a54fb 100644 --- a/arch/arm64/kernel/machine_kexec.c +++ b/arch/arm64/kernel/machine_kexec.c @@ -21,6 +21,7 @@ #include #include #include +#include #include "cpu-reset.h" @@ -71,11 +72,91 @@ static void *kexec_page_alloc(void *arg) return page_address(page); } +/* + * Map source segments starting from src_va, and map destination + * segments starting from dst_va, and return size of copy in + * *copy_len argument. + * Relocation function essentially needs to do: + * memcpy(dst_va, src_va, copy_len); + */ +static int map_segments(struct kimage *kimage, pgd_t *pgdp, + struct trans_pgd_info *info, + unsigned long src_va, + unsigned long dst_va, + unsigned long *copy_len) +{ + unsigned long *ptr = 0; + unsigned long dest = 0; + unsigned long len = 0; + unsigned long entry, addr; + int rc; + + for (entry = kimage->head; !(entry & IND_DONE); entry = *ptr++) { + addr = entry & PAGE_MASK; + + switch (entry & IND_FLAGS) { + case IND_DESTINATION: + dest = addr; + break; + case IND_INDIRECTION: + ptr = __va(addr); + if (rc) + return rc; + break; + case IND_SOURCE: + rc = trans_pgd_map_page(info, pgdp, __va(addr), + src_va, PAGE_KERNEL); + if (rc) + return rc; + rc = trans_pgd_map_page(info, pgdp, __va(dest), + dst_va, PAGE_KERNEL); + if (rc) + return rc; + dest += PAGE_SIZE; + src_va += PAGE_SIZE; + dst_va += PAGE_SIZE; + len += PAGE_SIZE; + } + } + *copy_len = len; + + return 0; +} + +static int mmu_relocate_setup(struct kimage *kimage, void *reloc_code, + struct kern_reloc_arg *kern_reloc_arg) +{ + struct trans_pgd_info info = { + .trans_alloc_page = kexec_page_alloc, + .trans_alloc_arg = kimage, + }; + pgd_t *trans_pgd = kexec_page_alloc(kimage); + int rc; + + if (!trans_pgd) + return -ENOMEM; + + /* idmap relocation function */ + rc = trans_pgd_idmap_page(&info, &kern_reloc_arg->trans_ttbr0, + &kern_reloc_arg->trans_t0sz, reloc_code); + if (rc) + return rc; + + kern_reloc_arg->src_addr = _PAGE_OFFSET(VA_BITS_MIN); + kern_reloc_arg->dst_addr = _PAGE_OFFSET(VA_BITS_MIN - 1); + kern_reloc_arg->trans_ttbr1 = phys_to_ttbr(__pa(trans_pgd)); + + rc = map_segments(kimage, trans_pgd, &info, kern_reloc_arg->src_addr, + kern_reloc_arg->dst_addr, &kern_reloc_arg->copy_len); + return rc; +} + int machine_kexec_post_load(struct kimage *kimage) { void *reloc_code = page_to_virt(kimage->control_code_page); struct kern_reloc_arg *kern_reloc_arg = kexec_page_alloc(kimage); long func_offset, vector_offset, reloc_size; + int rc = 0; if (!kern_reloc_arg) return -ENOMEM; @@ -95,6 +176,14 @@ int machine_kexec_post_load(struct kimage *kimage) if (is_hyp_mode_available() && !is_kernel_in_hyp_mode()) kern_reloc_arg->el2_vector = __pa(reloc_code) + vector_offset; + /* + * If relocation is not needed, we do not need to enable MMU in + * relocation routine, therefore do not create page tables for + * scenarios such as crash kernel + */ + if (!(kimage->head & IND_DONE)) + rc = mmu_relocate_setup(kimage, reloc_code, kern_reloc_arg); + kexec_image_info(kimage); /* Flush the reloc_code in preparation for its execution. */ @@ -103,7 +192,7 @@ int machine_kexec_post_load(struct kimage *kimage) reloc_size); __flush_dcache_area(kern_reloc_arg, sizeof(struct kern_reloc_arg)); - return 0; + return rc; } /** -- 2.25.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-qt1-x835.google.com ([2607:f8b0:4864:20::835]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l4C6o-0004v2-2N for kexec@lists.infradead.org; Tue, 26 Jan 2021 00:21:27 +0000 Received: by mail-qt1-x835.google.com with SMTP id t17so11148783qtq.2 for ; Mon, 25 Jan 2021 16:21:25 -0800 (PST) Subject: Re: [PATCH v10 16/18] arm64: kexec: configure trans_pgd page table for kexec References: <20210125191923.1060122-1-pasha.tatashin@soleen.com> <20210125191923.1060122-17-pasha.tatashin@soleen.com> From: Pavel Tatashin Message-ID: Date: Mon, 25 Jan 2021 19:21:22 -0500 MIME-Version: 1.0 In-Reply-To: <20210125191923.1060122-17-pasha.tatashin@soleen.com> Content-Language: en-US List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: jmorris@namei.org, sashal@kernel.org, ebiederm@xmission.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, corbet@lwn.net, catalin.marinas@arm.com, will@kernel.org, linux-arm-kernel@lists.infradead.org, maz@kernel.org, james.morse@arm.com, vladimir.murzin@arm.com, matthias.bgg@gmail.com, linux-mm@kvack.org, mark.rutland@arm.com, steve.capper@arm.com, rfontana@redhat.com, tglx@linutronix.de, selindag@gmail.com, tyhicks@linux.microsoft.com I forgot to make changes to arch/arm64/Kconfig. The correct patch is below. --- >From a2bc374320d7c7efd3c40644ad3d6d59a024b301 Mon Sep 17 00:00:00 2001 From: Pavel Tatashin Date: Mon, 29 Jul 2019 21:24:25 -0400 Subject: [PATCH v10 16/18] arm64: kexec: configure trans_pgd page table for kexec Configure a page table located in kexec-safe memory that has the following mappings: 1. identity mapping for text of relocation function with executable permission. 2. va mappings for all source ranges 3. va mappings for all destination ranges. Signed-off-by: Pavel Tatashin --- arch/arm64/Kconfig | 2 +- arch/arm64/include/asm/kexec.h | 12 ++++ arch/arm64/kernel/asm-offsets.c | 6 ++ arch/arm64/kernel/machine_kexec.c | 91 ++++++++++++++++++++++++++++++- 4 files changed, 109 insertions(+), 2 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index fc0ed9d6e011..440abd0c0ee1 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1134,7 +1134,7 @@ config CRASH_DUMP config TRANS_TABLE def_bool y - depends on HIBERNATION + depends on HIBERNATION || KEXEC_CORE config XEN_DOM0 def_bool y diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h index b96d8a6aac80..049cde429b1b 100644 --- a/arch/arm64/include/asm/kexec.h +++ b/arch/arm64/include/asm/kexec.h @@ -105,6 +105,12 @@ extern const char arm64_kexec_el2_vectors[]; * el2_vector If present means that relocation routine will go to EL1 * from EL2 to do the copy, and then back to EL2 to do the jump * to new world. + * trans_ttbr0 idmap for relocation function and its argument + * trans_ttbr1 map for source/destination addresses. + * trans_t0sz t0sz for idmap page in trans_ttbr0 + * src_addr start address for source pages. + * dst_addr start address for destination pages. + * copy_len Number of bytes that need to be copied */ struct kern_reloc_arg { phys_addr_t head; @@ -114,6 +120,12 @@ struct kern_reloc_arg { phys_addr_t kern_arg2; phys_addr_t kern_arg3; phys_addr_t el2_vector; + phys_addr_t trans_ttbr0; + phys_addr_t trans_ttbr1; + unsigned long trans_t0sz; + unsigned long src_addr; + unsigned long dst_addr; + unsigned long copy_len; }; #define ARCH_HAS_KIMAGE_ARCH diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index 8a9475be1b62..06278611451d 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -160,6 +160,12 @@ int main(void) DEFINE(KEXEC_KRELOC_KERN_ARG2, offsetof(struct kern_reloc_arg, kern_arg2)); DEFINE(KEXEC_KRELOC_KERN_ARG3, offsetof(struct kern_reloc_arg, kern_arg3)); DEFINE(KEXEC_KRELOC_EL2_VECTOR, offsetof(struct kern_reloc_arg, el2_vector)); + DEFINE(KEXEC_KRELOC_TRANS_TTBR0, offsetof(struct kern_reloc_arg, trans_ttbr0)); + DEFINE(KEXEC_KRELOC_TRANS_TTBR1, offsetof(struct kern_reloc_arg, trans_ttbr1)); + DEFINE(KEXEC_KRELOC_TRANS_T0SZ, offsetof(struct kern_reloc_arg, trans_t0sz)); + DEFINE(KEXEC_KRELOC_SRC_ADDR, offsetof(struct kern_reloc_arg, src_addr)); + DEFINE(KEXEC_KRELOC_DST_ADDR, offsetof(struct kern_reloc_arg, dst_addr)); + DEFINE(KEXEC_KRELOC_COPY_LEN, offsetof(struct kern_reloc_arg, copy_len)); #endif return 0; } diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c index 41d1e3ca13f8..dc1b7e5a54fb 100644 --- a/arch/arm64/kernel/machine_kexec.c +++ b/arch/arm64/kernel/machine_kexec.c @@ -21,6 +21,7 @@ #include #include #include +#include #include "cpu-reset.h" @@ -71,11 +72,91 @@ static void *kexec_page_alloc(void *arg) return page_address(page); } +/* + * Map source segments starting from src_va, and map destination + * segments starting from dst_va, and return size of copy in + * *copy_len argument. + * Relocation function essentially needs to do: + * memcpy(dst_va, src_va, copy_len); + */ +static int map_segments(struct kimage *kimage, pgd_t *pgdp, + struct trans_pgd_info *info, + unsigned long src_va, + unsigned long dst_va, + unsigned long *copy_len) +{ + unsigned long *ptr = 0; + unsigned long dest = 0; + unsigned long len = 0; + unsigned long entry, addr; + int rc; + + for (entry = kimage->head; !(entry & IND_DONE); entry = *ptr++) { + addr = entry & PAGE_MASK; + + switch (entry & IND_FLAGS) { + case IND_DESTINATION: + dest = addr; + break; + case IND_INDIRECTION: + ptr = __va(addr); + if (rc) + return rc; + break; + case IND_SOURCE: + rc = trans_pgd_map_page(info, pgdp, __va(addr), + src_va, PAGE_KERNEL); + if (rc) + return rc; + rc = trans_pgd_map_page(info, pgdp, __va(dest), + dst_va, PAGE_KERNEL); + if (rc) + return rc; + dest += PAGE_SIZE; + src_va += PAGE_SIZE; + dst_va += PAGE_SIZE; + len += PAGE_SIZE; + } + } + *copy_len = len; + + return 0; +} + +static int mmu_relocate_setup(struct kimage *kimage, void *reloc_code, + struct kern_reloc_arg *kern_reloc_arg) +{ + struct trans_pgd_info info = { + .trans_alloc_page = kexec_page_alloc, + .trans_alloc_arg = kimage, + }; + pgd_t *trans_pgd = kexec_page_alloc(kimage); + int rc; + + if (!trans_pgd) + return -ENOMEM; + + /* idmap relocation function */ + rc = trans_pgd_idmap_page(&info, &kern_reloc_arg->trans_ttbr0, + &kern_reloc_arg->trans_t0sz, reloc_code); + if (rc) + return rc; + + kern_reloc_arg->src_addr = _PAGE_OFFSET(VA_BITS_MIN); + kern_reloc_arg->dst_addr = _PAGE_OFFSET(VA_BITS_MIN - 1); + kern_reloc_arg->trans_ttbr1 = phys_to_ttbr(__pa(trans_pgd)); + + rc = map_segments(kimage, trans_pgd, &info, kern_reloc_arg->src_addr, + kern_reloc_arg->dst_addr, &kern_reloc_arg->copy_len); + return rc; +} + int machine_kexec_post_load(struct kimage *kimage) { void *reloc_code = page_to_virt(kimage->control_code_page); struct kern_reloc_arg *kern_reloc_arg = kexec_page_alloc(kimage); long func_offset, vector_offset, reloc_size; + int rc = 0; if (!kern_reloc_arg) return -ENOMEM; @@ -95,6 +176,14 @@ int machine_kexec_post_load(struct kimage *kimage) if (is_hyp_mode_available() && !is_kernel_in_hyp_mode()) kern_reloc_arg->el2_vector = __pa(reloc_code) + vector_offset; + /* + * If relocation is not needed, we do not need to enable MMU in + * relocation routine, therefore do not create page tables for + * scenarios such as crash kernel + */ + if (!(kimage->head & IND_DONE)) + rc = mmu_relocate_setup(kimage, reloc_code, kern_reloc_arg); + kexec_image_info(kimage); /* Flush the reloc_code in preparation for its execution. */ @@ -103,7 +192,7 @@ int machine_kexec_post_load(struct kimage *kimage) reloc_size); __flush_dcache_area(kern_reloc_arg, sizeof(struct kern_reloc_arg)); - return 0; + return rc; } /** -- 2.25.1 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec