From patchwork Wed Oct 16 20:00:32 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pasha Tatashin X-Patchwork-Id: 11194131 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 8DB9415AB for ; Wed, 16 Oct 2019 20:01:54 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3FB9A218DE for ; Wed, 16 Oct 2019 20:01:54 +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="aP7fs4fa" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3FB9A218DE 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 C11AC8E001C; Wed, 16 Oct 2019 16:01:15 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id BC0F48E000C; Wed, 16 Oct 2019 16:01:15 -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 AAFD78E001C; Wed, 16 Oct 2019 16:01:15 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0190.hostedemail.com [216.40.44.190]) by kanga.kvack.org (Postfix) with ESMTP id 7FD1A8E000C for ; Wed, 16 Oct 2019 16:01:15 -0400 (EDT) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with SMTP id 1E6A11844CAAD for ; Wed, 16 Oct 2019 20:01:15 +0000 (UTC) X-FDA: 76050716910.10.flame04_ad625faea617 X-Spam-Summary: 2,0,0,a1c3bf4ccd6b17df,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:steve.capper@arm.com:rfontana@redhat.com:tglx@linutronix.de,RULES_HIT:1:2:41:355:379:541:800:960:973:988:989:1260:1311:1314:1345:1359:1381:1431:1437:1515:1605:1730:1747:1777:1792:2194:2199:2393:2559:2562:2693:3138:3139:3140:3141:3142:3865:3866:3867:3868:3870:3871:3874:4049:4250:4321:4605:5007:6119:6261:6653:6737:7875:7903:8603:9036:10004:11026:11473:11657:11658:11914:12043:12048:12291:12296:12297:12438:12517:12519:12555:12683:12895:13161:13229:13548:13894:14096:14394:21063:21080:21433:21444:21451:21611:21627:30034:30054:30070:30075:30079,0, RBL:209. X-HE-Tag: flame04_ad625faea617 X-Filterd-Recvd-Size: 10059 Received: from mail-qt1-f193.google.com (mail-qt1-f193.google.com [209.85.160.193]) by imf12.hostedemail.com (Postfix) with ESMTP for ; Wed, 16 Oct 2019 20:01:14 +0000 (UTC) Received: by mail-qt1-f193.google.com with SMTP id n17so18630095qtr.4 for ; Wed, 16 Oct 2019 13:01:14 -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=uFvf/fXznSnIHF7tnFK87S0+X7xt7Kheg1PwfwzAB1w=; b=aP7fs4faRfvESpCSQvMzu2kYpom8AcZbECTaP6g9QcH2usBGWsH6vHV95nyhtBjABo 7+fY57pBpeIcsukuKgcsw4e1zLLFY8fUa+03K3SyOUSkR5UcQSGip8n9VevkPK5PoY8W CLcIwncsSdUOUj3YNrok1BWN2YYnbnMWquAJGTlpeSvsKscjcXkrvJcoG9bFYucZgiFA KNuYCVyXVpKTmJBLmxjlmPdhRKi2DkgrcAQnL4RoNVM8DYhKwRBNi3iVkyFzsLMHScmy HhnUoDK3HO5Gz8GL2R7sSj2PXmXBc+lfOAW52ffPN2A8BZ9B2FCL/xGE5mROZRipMeyb iEtg== 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=uFvf/fXznSnIHF7tnFK87S0+X7xt7Kheg1PwfwzAB1w=; b=gfc3aREbQD8XmRCfxE4NRjUkeJaqu7/3Q1k9+1uWCwFroOB5DXgFabYOfG28J3hc82 Uks7jcrM+OOtWoXfpW5uiTvKfgdI6Px5KKTIPm84UDlPsPr3jfBXfQbn7tQ+MP54fSFu t8ahG/zSysUCgvvXxZkSEkPTkiaYaOlAnrVn8hjiDnbAt82EMCziCZp9KRc52emXe6zn iYl3AakRT6QYCoeOzPgoRHC6XV7iLilqdY3ZcJximwPjpuYAzO8eNSRWAKqlwI7yWkpx sC3eSYbDtFQaHmOZla2O1B3gvAnxFfGQyATik0VGJ5S4utqh2XbYOQ8nAvOuCCE3LpRt 9IwA== X-Gm-Message-State: APjAAAUOe2OVpecDqMrPA5w/KE7jE8DQnJ8tlwiW6Suilq7+Y13TJEE0 FT6qTitve8p6PVf3o641NozGEg== X-Google-Smtp-Source: APXvYqyQE0hatidBKOwaY2TrTHlSI+T2qJiEPKvWKsbUagw1I5BzNoRHbfRQOkaJ2BZWJ8GKry4SMQ== X-Received: by 2002:aed:3fdb:: with SMTP id w27mr47685828qth.223.1571256073488; Wed, 16 Oct 2019 13:01:13 -0700 (PDT) Received: from localhost.localdomain (c-73-69-118-222.hsd1.nh.comcast.net. [73.69.118.222]) by smtp.gmail.com with ESMTPSA id c204sm13342030qkb.90.2019.10.16.13.01.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 16 Oct 2019 13:01:12 -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, steve.capper@arm.com, rfontana@redhat.com, tglx@linutronix.de Subject: [PATCH v7 23/25] arm64: kexec: configure trans_pgd page table for kexec Date: Wed, 16 Oct 2019 16:00:32 -0400 Message-Id: <20191016200034.1342308-24-pasha.tatashin@soleen.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191016200034.1342308-1-pasha.tatashin@soleen.com> References: <20191016200034.1342308-1-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. Signed-off-by: Pavel Tatashin --- arch/arm64/include/asm/kexec.h | 14 ++++ arch/arm64/kernel/asm-offsets.c | 5 ++ arch/arm64/kernel/machine_kexec.c | 104 +++++++++++++++++++++++++++++- 3 files changed, 122 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h index 414a0a41a60a..df911a4aa8ce 100644 --- a/arch/arm64/include/asm/kexec.h +++ b/arch/arm64/include/asm/kexec.h @@ -98,6 +98,10 @@ extern const unsigned long kexec_kern_reloc_offset; extern const unsigned long kexec_el2_vectors_offset; #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. @@ -108,6 +112,11 @@ extern const unsigned long kexec_el2_vectors_offset; * 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 linear map for source/destination addresses. + * 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 { phys_addr_t head; @@ -117,6 +126,11 @@ 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; + void *src_addr; + void *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 ad7764d68904..4147d9d70c1c 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -136,6 +136,11 @@ 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_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 ac6ade7c96ff..8edcc4be0b15 100644 --- a/arch/arm64/kernel/machine_kexec.c +++ b/arch/arm64/kernel/machine_kexec.c @@ -20,6 +20,7 @@ #include #include #include +#include #include "cpu-reset.h" @@ -70,10 +71,102 @@ 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, 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_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, reloc_code, + __pa(reloc_code), 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 = (void *)KEXEC_SRC_START; + kern_reloc_arg->dst_addr = (void *)KEXEC_DST_START; + + return 0; +} + 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); + int rc = 0; if (!kern_reloc_arg) return -ENOMEM; @@ -89,9 +182,18 @@ int machine_kexec_post_load(struct kimage *kimage) kern_reloc_arg->el2_vector = __pa(reloc_code) + kexec_el2_vectors_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); - return 0; + return rc; }