From patchwork Mon Sep 23 20:34:26 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 11157601 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DF4391599 for ; Mon, 23 Sep 2019 20:35:25 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9E51220673 for ; Mon, 23 Sep 2019 20:35:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=soleen.com header.i=@soleen.com header.b="OGxUtTFa" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9E51220673 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=soleen.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 69B766B02A0; Mon, 23 Sep 2019 16:35:22 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 6539C6B02A1; Mon, 23 Sep 2019 16:35:22 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4ED976B02A2; Mon, 23 Sep 2019 16:35:22 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0044.hostedemail.com [216.40.44.44]) by kanga.kvack.org (Postfix) with ESMTP id 2D2FE6B02A0 for ; Mon, 23 Sep 2019 16:35:22 -0400 (EDT) Received: from smtpin29.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id C122A181AC9BA for ; Mon, 23 Sep 2019 20:35:21 +0000 (UTC) X-FDA: 75967340442.29.join95_860974df1dd3a X-Spam-Summary: 2,0,0,53213cff6ed49cee,d41d8cd98f00b204,pasha.tatashin@soleen.com,:pasha.tatashin@soleen.com: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:marc.zyngier@arm.com:james.morse@arm.com:vladimir.murzin@arm.com:matthias.bgg@gmail.com:bhsharma@redhat.com::mark.rutland@arm.com,RULES_HIT:1:2:41:355:379:541:800:960:973:988:989:1260:1311:1314:1345:1359:1381:1431:1437:1500:1515:1605:1730:1747:1777:1792:2194:2199:2393:2559:2562:2693:3138:3139:3140:3141:3142:3865:3866:3867:3868:3870:3871:3874:4052:4250:4321:4605:5007:6119:6261:6653:6737:7875:7903:8603:9036:9592:10004:11026:11473:11657:11658:11914:12043:12048:12291:12295:12296:12297:12438:12517:12519:12555:12895:12986:13161:13229:13548:13894:14096:14394:21063:21080:21433:21444:21451:21627:30003:30034:30054:30070:30075:30079,0,RBL:209.85.215.194:@soleen.com:.lbl8.mailshe ll.net-6 X-HE-Tag: join95_860974df1dd3a X-Filterd-Recvd-Size: 13146 Received: from mail-pg1-f194.google.com (mail-pg1-f194.google.com [209.85.215.194]) by imf49.hostedemail.com (Postfix) with ESMTP for ; Mon, 23 Sep 2019 20:35:20 +0000 (UTC) Received: by mail-pg1-f194.google.com with SMTP id 4so8623111pgm.12 for ; Mon, 23 Sep 2019 13:35:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=soleen.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=1RZkZY1cm3fyZ1mRNLzSw31HBeKwrW9anL0qGMNckK8=; b=OGxUtTFa9LaWeK9KWDL+UrpALkAR0k4TOpQ/i5LOqHeEZUnm9DzsAJH0AJoYBMJyCq AJAkfoRHvjs7vrby58uPHeZVHQuHzxJq0zIilBoi5UL1euBtHrkenJI7AY4dD4Uaz0JG 8CuvUY9Rr1En5VdqB9AF0arxAtsqsFfospIeoHu5RcflKy5E9k3SY/Eee/yh/L4kivDM Sy6QctDd+iWsKf7muddwV5gbQEEhohuxP2PlbCdVQwr411Vs9fyZ8JS0yTNvuQMDtDhs e3tT8fIoTpvCURZVTF+CWRAUVCytkY835vqmtVOOIxqQdoDVApa6XffZ96s6fnKGUq5f KFww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=1RZkZY1cm3fyZ1mRNLzSw31HBeKwrW9anL0qGMNckK8=; b=MPqDgMRMJbC3zCTC6Wjq0ffH7fp+pMc3DaDdB/NtBOn5l6KxJ63NaIzNYJEr4iyEF6 6RtxpQGaJ6oaZOZ4uUS4mDJGOxd70jmpWiKCcoijFAYfZywswDWsr3l4MxZp735XL+5g jNJ3OlC+u3Xs5jlKb+pGOZtvzkcBnPummPKosCf+N7hoGedmETq+ho5q116o6DuPNsBb qwKBRpSLv7wcrFGq7Lw/DOoVv6m5iU1U5oSZFXZn23Y+TLpF0E2z1c1bWaRH8Z9U9gmv x0X6LtBAufG3/Fm8yicSLHrokdRn0TPVpPYwjOF/iCVfrMfTthlfJcrAaYCpbuvUW5zK w6lQ== X-Gm-Message-State: APjAAAWlXaZofS4B5g5Jy5APrCPLuPIUhJ+aN9kZQqt98w7+5V8uMktD XAtixzT6iSlSXk69RgiChDki7A== X-Google-Smtp-Source: APXvYqySVpP3jOsDcUDVSEo8IRqXfNNcCJU5Z6f4uLaJN3tO9ol6cdCc0j5ahgjr6Yxtc3Lb9w5hEw== X-Received: by 2002:a63:a54c:: with SMTP id r12mr1758722pgu.5.1569270919910; Mon, 23 Sep 2019 13:35:19 -0700 (PDT) Received: from xakep.corp.microsoft.com (c-73-69-118-222.hsd1.nh.comcast.net. [73.69.118.222]) by smtp.gmail.com with ESMTPSA id n29sm12798676pgm.4.2019.09.23.13.35.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 Sep 2019 13:35:19 -0700 (PDT) From: Pavel Tatashin To: pasha.tatashin@soleen.com, 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, marc.zyngier@arm.com, james.morse@arm.com, vladimir.murzin@arm.com, matthias.bgg@gmail.com, bhsharma@redhat.com, linux-mm@kvack.org, mark.rutland@arm.com Subject: [PATCH v5 16/17] arm64: kexec: configure trans_pgd page table for kexec Date: Mon, 23 Sep 2019 16:34:26 -0400 Message-Id: <20190923203427.294286-17-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190923203427.294286-1-pasha.tatashin@soleen.com> References: <20190923203427.294286-1-pasha.tatashin@soleen.com> MIME-Version: 1.0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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. identity mapping for argument for relocation function. 3. linear mappings for all source ranges 4. linear mappings for all destination ranges. Also, configure el2_vector, that is used to jump to new kernel from EL2 on non-VHE kernels. Signed-off-by: Pavel Tatashin --- arch/arm64/include/asm/kexec.h | 32 +++++++ arch/arm64/kernel/asm-offsets.c | 6 ++ arch/arm64/kernel/machine_kexec.c | 125 ++++++++++++++++++++++++++-- arch/arm64/kernel/relocate_kernel.S | 16 +++- 4 files changed, 170 insertions(+), 9 deletions(-) diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h index d5b79d4c7fae..450d8440f597 100644 --- a/arch/arm64/include/asm/kexec.h +++ b/arch/arm64/include/asm/kexec.h @@ -90,6 +90,23 @@ static inline void crash_prepare_suspend(void) {} static inline void crash_post_resume(void) {} #endif +#if defined(CONFIG_KEXEC_CORE) +/* Global variables for the arm64_relocate_new_kernel routine. */ +extern const unsigned char arm64_relocate_new_kernel[]; +extern const unsigned long arm64_relocate_new_kernel_size; + +/* Body of the vector for escalating to EL2 from relocation routine */ +extern const unsigned char kexec_el1_sync[]; +extern const unsigned long kexec_el1_sync_size; + +#define KEXEC_EL2_VECTOR_TABLE_SIZE 2048 +#define KEXEC_EL2_SYNC_OFFSET (KEXEC_EL2_VECTOR_TABLE_SIZE / 2) + +#endif + +#define KEXEC_SRC_START PAGE_OFFSET +#define KEXEC_DST_START (PAGE_OFFSET + \ + ((UL(0xffffffffffffffff) - PAGE_OFFSET) >> 1) + 1) /* * kern_reloc_arg is passed to kernel relocation function as an argument. * head kimage->head, allows to traverse through relocation segments. @@ -97,6 +114,15 @@ static inline void crash_post_resume(void) {} * kernel, or purgatory entry address). * kern_arg0 first argument to kernel is its dtb address. The other * arguments are currently unused, and must be set to 0 + * trans_ttbr0 idmap for relocation function and its argument + * trans_ttbr1 linear map for source/destination addresses. + * 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. This vector contains only the final jump + * instruction at KEXEC_EL2_SYNC_OFFSET. + * src_addr linear map for source pages. + * dst_addr linear map for destination pages. + * copy_len Number of bytes that need to be copied */ struct kern_reloc_arg { unsigned long head; @@ -105,6 +131,12 @@ struct kern_reloc_arg { unsigned long kern_arg1; unsigned long kern_arg2; unsigned long kern_arg3; + unsigned long trans_ttbr0; + unsigned long trans_ttbr1; + unsigned long el2_vector; + 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 900394907fd8..7c2ba09a8ceb 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -135,6 +135,12 @@ int main(void) DEFINE(KRELOC_KERN_ARG1, offsetof(struct kern_reloc_arg, kern_arg1)); DEFINE(KRELOC_KERN_ARG2, offsetof(struct kern_reloc_arg, kern_arg2)); DEFINE(KRELOC_KERN_ARG3, offsetof(struct kern_reloc_arg, kern_arg3)); + DEFINE(KRELOC_TRANS_TTBR0, offsetof(struct kern_reloc_arg, trans_ttbr0)); + DEFINE(KRELOC_TRANS_TTBR1, offsetof(struct kern_reloc_arg, trans_ttbr1)); + DEFINE(KRELOC_EL2_VECTOR, offsetof(struct kern_reloc_arg, el2_vector)); + DEFINE(KRELOC_SRC_ADDR, offsetof(struct kern_reloc_arg, src_addr)); + DEFINE(KRELOC_DST_ADDR, offsetof(struct kern_reloc_arg, dst_addr)); + DEFINE(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 fb6138a1c9ff..71479013dd24 100644 --- a/arch/arm64/kernel/machine_kexec.c +++ b/arch/arm64/kernel/machine_kexec.c @@ -20,13 +20,10 @@ #include #include #include +#include #include "cpu-reset.h" -/* Global variables for the arm64_relocate_new_kernel routine. */ -extern const unsigned char arm64_relocate_new_kernel[]; -extern const unsigned long arm64_relocate_new_kernel_size; - /** * kexec_image_info - For debugging output. */ @@ -74,15 +71,124 @@ static void *kexec_page_alloc(void *arg) return page_address(page); } +/* + * Map source segments starting from KEXEC_SRC_START, and map destination + * segments starting from KEXEC_DST_START, and return size of copy in + * *copy_len argument. + * Relocation function essentially needs to do: + * memcpy(KEXEC_DST_START, KEXEC_SRC_START, copy_len); + */ +static int map_segments(struct kimage *kimage, pgd_t *pgdp, + struct trans_pgd_info *info, + unsigned long *copy_len) +{ + unsigned long *ptr = 0; + unsigned long dest = 0; + unsigned long src_va = KEXEC_SRC_START; + unsigned long dst_va = KEXEC_DST_START; + 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, unsigned long kern_reloc, + 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_ttbr0 = kexec_page_alloc(kimage); + pgd_t *trans_ttbr1 = kexec_page_alloc(kimage); + int rc; + + if (!trans_ttbr0 || !trans_ttbr1) + return -ENOMEM; + + rc = map_segments(kimage, trans_ttbr1, &info, + &kern_reloc_arg->copy_len); + if (rc) + return rc; + + /* Map relocation function va == pa */ + rc = trans_pgd_map_page(&info, trans_ttbr0, __va(kern_reloc), + kern_reloc, PAGE_KERNEL_EXEC); + if (rc) + return rc; + + /* Map relocation function argument va == pa */ + rc = trans_pgd_map_page(&info, trans_ttbr0, kern_reloc_arg, + __pa(kern_reloc_arg), PAGE_KERNEL); + if (rc) + return rc; + + kern_reloc_arg->trans_ttbr0 = phys_to_ttbr(__pa(trans_ttbr0)); + kern_reloc_arg->trans_ttbr1 = phys_to_ttbr(__pa(trans_ttbr1)); + kern_reloc_arg->src_addr = KEXEC_SRC_START; + kern_reloc_arg->dst_addr = KEXEC_DST_START; + + return 0; +} + int machine_kexec_post_load(struct kimage *kimage) { + unsigned long el2_vector = 0; unsigned long kern_reloc; struct kern_reloc_arg *kern_reloc_arg; + int rc = 0; + + /* + * Sanity check that relocation function + el2_vector fit into one + * page. + */ + if (arm64_relocate_new_kernel_size > KEXEC_EL2_VECTOR_TABLE_SIZE) { + pr_err("can't fit relocation function and el2_vector in one page"); + return -ENOMEM; + } kern_reloc = page_to_phys(kimage->control_code_page); memcpy(__va(kern_reloc), arm64_relocate_new_kernel, arm64_relocate_new_kernel_size); + /* Setup vector table only when EL2 is available, but no VHE */ + if (is_hyp_mode_available() && !is_kernel_in_hyp_mode()) { + el2_vector = kern_reloc + KEXEC_EL2_VECTOR_TABLE_SIZE; + memcpy(__va(el2_vector + KEXEC_EL2_SYNC_OFFSET), kexec_el1_sync, + kexec_el1_sync_size); + } + kern_reloc_arg = kexec_page_alloc(kimage); if (!kern_reloc_arg) return -ENOMEM; @@ -92,10 +198,19 @@ int machine_kexec_post_load(struct kimage *kimage) kern_reloc_arg->head = kimage->head; kern_reloc_arg->entry_addr = kimage->start; + kern_reloc_arg->el2_vector = el2_vector; kern_reloc_arg->kern_arg0 = kimage->arch.dtb_mem; + /* + * 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, kern_reloc, kern_reloc_arg); + kexec_image_info(kimage); - return 0; + return rc; } /** diff --git a/arch/arm64/kernel/relocate_kernel.S b/arch/arm64/kernel/relocate_kernel.S index d352faf7cbe6..14243a678277 100644 --- a/arch/arm64/kernel/relocate_kernel.S +++ b/arch/arm64/kernel/relocate_kernel.S @@ -83,17 +83,25 @@ ENTRY(arm64_relocate_new_kernel) ldr x1, [x0, #KRELOC_KERN_ARG1] ldr x0, [x0, #KRELOC_KERN_ARG0] /* x0 = dtb address */ br x4 +.ltorg +.Larm64_relocate_new_kernel_end: END(arm64_relocate_new_kernel) -.ltorg +ENTRY(kexec_el1_sync) + br x4 /* Jump to new world from el2 */ +.Lkexec_el1_sync_end: +END(kexec_el1_sync) + .align 3 /* To keep the 64-bit values below naturally aligned. */ -.Lcopy_end: .org KEXEC_CONTROL_PAGE_SIZE - /* * arm64_relocate_new_kernel_size - Number of bytes to copy to the * control_code_page. */ .globl arm64_relocate_new_kernel_size arm64_relocate_new_kernel_size: - .quad .Lcopy_end - arm64_relocate_new_kernel + .quad .Larm64_relocate_new_kernel_end - arm64_relocate_new_kernel + +.globl kexec_el1_sync_size +kexec_el1_sync_size: + .quad .Lkexec_el1_sync_end - kexec_el1_sync