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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=ham 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 91108C2D0E4 for ; Tue, 24 Nov 2020 20:00:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 43D3A2067D for ; Tue, 24 Nov 2020 20:00:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="hurQCtcs" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729866AbgKXT75 (ORCPT ); Tue, 24 Nov 2020 14:59:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38130 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729774AbgKXT7z (ORCPT ); Tue, 24 Nov 2020 14:59:55 -0500 Received: from mail-qt1-x84a.google.com (mail-qt1-x84a.google.com [IPv6:2607:f8b0:4864:20::84a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2EDA8C0613D6 for ; Tue, 24 Nov 2020 11:59:54 -0800 (PST) Received: by mail-qt1-x84a.google.com with SMTP id f19so2549644qtx.6 for ; Tue, 24 Nov 2020 11:59:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=WXbcQWvdWDLVC5jHOswTFrpCLxCuVOiUOcyyKJaeh/g=; b=hurQCtcsEarRy0HRrRrdpGlHFG8T6ntiY+W8DibV3UoYqNtuiPUoho9HjblqNH52ve 9muorssfxUCj/uJuGe2RRWCVB5sKHeKxDzL9PlWr8sHuUL/0Td/nQ9dcfme3BK4JaECN 0LyZTZcb9isPJuGGbU5djI5HJn1hEl/UERcsnV1LZGeOMd1xbMAjlC+sanpB2L3sTgkq pQcj6IKUIfsgrDvR2t3g0+w/UT+kiKzFix3w2yhFNmtfw6QW9hXqB+nJhNXrh/LSl1/K xUOjnKcnK73gCxt/HHZOQmWYlVRDMgCiZuNbOZUjeKx0rR9QRzWM7Fjqb5g9ZTloPyvq Aa4w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=WXbcQWvdWDLVC5jHOswTFrpCLxCuVOiUOcyyKJaeh/g=; b=qR+6uQlYdEFxkyxfrx0RP9GqOkAmfFXMilKxTIsOcVkg+5jsNaCjbWFgIdGTlKUwMB V1tsI7Joq3Bz1puIvNeN2gnzta41otOOjez6+CMMSBiaMYEfTLwOOfu69KBCVLGKFLAh ish2CafF1PQR7L+703jf/ftKVWzBRap+9CnJoTp89piD8yuQj51HmYePIdQOe4IOEW4Q KZbtzp1IVex8KyVosijTm7go/YhZf3pU5R83hl0siIyb+cOsuaGACwVtS2N8d5Tba1Az n1eg6Piro2nfsRKItCTwLR8WWFVpHv3/Aff6m1kORfKVxBMq5uAUEbrjqNVgT/+kdKdm UMug== X-Gm-Message-State: AOAM532DGlAcEreawzd2LD869aqzqZbx8UQjc/B+toTvxcZCwlIZ4b6O 2G5Hw1GkIKfOXNFXiodzXhQE6y91Y08LxMAkLNM= X-Google-Smtp-Source: ABdhPJwz/b68ErbwAINA1DmsvIFCJSbOy4bc1aE3NJXrgYnPJF4Xsm8gnyly0MqpDkHkNvc5NEgy+sTiYJlDL/Kzg3M= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:ad4:4661:: with SMTP id z1mr239900qvv.19.1606247993327; Tue, 24 Nov 2020 11:59:53 -0800 (PST) Date: Tue, 24 Nov 2020 11:59:40 -0800 In-Reply-To: <20201124195940.27061-1-samitolvanen@google.com> Message-Id: <20201124195940.27061-3-samitolvanen@google.com> Mime-Version: 1.0 References: <20201124195940.27061-1-samitolvanen@google.com> X-Mailer: git-send-email 2.29.2.454.gaff20da3a2-goog Subject: [PATCH v2 2/2] arm64: scs: use vmapped IRQ and SDEI shadow stacks From: Sami Tolvanen To: Will Deacon , Catalin Marinas Cc: Mark Rutland , James Morse , Ard Biesheuvel , Kees Cook , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Sami Tolvanen Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Use scs_alloc() to allocate also IRQ and SDEI shadow stacks instead of using statically allocated stacks. Signed-off-by: Sami Tolvanen --- arch/arm64/kernel/Makefile | 1 - arch/arm64/kernel/entry.S | 6 ++-- arch/arm64/kernel/irq.c | 19 ++++++++++ arch/arm64/kernel/scs.c | 16 --------- arch/arm64/kernel/sdei.c | 71 +++++++++++++++++++++++++++++++------- include/linux/scs.h | 4 --- 6 files changed, 81 insertions(+), 36 deletions(-) delete mode 100644 arch/arm64/kernel/scs.c diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index bbaf0bc4ad60..86364ab6f13f 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -58,7 +58,6 @@ obj-$(CONFIG_CRASH_DUMP) += crash_dump.o obj-$(CONFIG_CRASH_CORE) += crash_core.o obj-$(CONFIG_ARM_SDE_INTERFACE) += sdei.o obj-$(CONFIG_ARM64_PTR_AUTH) += pointer_auth.o -obj-$(CONFIG_SHADOW_CALL_STACK) += scs.o obj-$(CONFIG_ARM64_MTE) += mte.o obj-y += vdso/ probes/ diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index b295fb912b12..5c2ac4b5b2da 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -441,7 +441,7 @@ SYM_CODE_END(__swpan_exit_el0) #ifdef CONFIG_SHADOW_CALL_STACK /* also switch to the irq shadow stack */ - adr_this_cpu scs_sp, irq_shadow_call_stack, x26 + ldr_this_cpu scs_sp, irq_shadow_call_stack_ptr, x26 #endif 9998: @@ -1097,9 +1097,9 @@ SYM_CODE_START(__sdei_asm_handler) #ifdef CONFIG_SHADOW_CALL_STACK /* Use a separate shadow call stack for normal and critical events */ cbnz w4, 3f - adr_this_cpu dst=scs_sp, sym=sdei_shadow_call_stack_normal, tmp=x6 + ldr_this_cpu dst=scs_sp, sym=sdei_shadow_call_stack_normal_ptr, tmp=x6 b 4f -3: adr_this_cpu dst=scs_sp, sym=sdei_shadow_call_stack_critical, tmp=x6 +3: ldr_this_cpu dst=scs_sp, sym=sdei_shadow_call_stack_critical_ptr, tmp=x6 4: #endif diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c index 9cf2fb87584a..5b7ada9d9559 100644 --- a/arch/arm64/kernel/irq.c +++ b/arch/arm64/kernel/irq.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include #include @@ -27,6 +28,22 @@ DEFINE_PER_CPU(struct nmi_ctx, nmi_contexts); DEFINE_PER_CPU(unsigned long *, irq_stack_ptr); + +DECLARE_PER_CPU(unsigned long *, irq_shadow_call_stack_ptr); + +#ifdef CONFIG_SHADOW_CALL_STACK +DEFINE_PER_CPU(unsigned long *, irq_shadow_call_stack_ptr); +#endif + +static void init_irq_scs(void) +{ + int cpu; + + for_each_possible_cpu(cpu) + per_cpu(irq_shadow_call_stack_ptr, cpu) = + scs_alloc(cpu_to_node(cpu)); +} + #ifdef CONFIG_VMAP_STACK static void init_irq_stacks(void) { @@ -54,6 +71,8 @@ static void init_irq_stacks(void) void __init init_IRQ(void) { init_irq_stacks(); + if (IS_ENABLED(CONFIG_SHADOW_CALL_STACK)) + init_irq_scs(); irqchip_init(); if (!handle_arch_irq) panic("No interrupt controller found."); diff --git a/arch/arm64/kernel/scs.c b/arch/arm64/kernel/scs.c deleted file mode 100644 index e8f7ff45dd8f..000000000000 --- a/arch/arm64/kernel/scs.c +++ /dev/null @@ -1,16 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Shadow Call Stack support. - * - * Copyright (C) 2019 Google LLC - */ - -#include -#include - -DEFINE_SCS(irq_shadow_call_stack); - -#ifdef CONFIG_ARM_SDE_INTERFACE -DEFINE_SCS(sdei_shadow_call_stack_normal); -DEFINE_SCS(sdei_shadow_call_stack_critical); -#endif diff --git a/arch/arm64/kernel/sdei.c b/arch/arm64/kernel/sdei.c index 7689f2031c0c..cbc370d3bb4f 100644 --- a/arch/arm64/kernel/sdei.c +++ b/arch/arm64/kernel/sdei.c @@ -7,6 +7,7 @@ #include #include #include +#include #include #include @@ -37,6 +38,14 @@ DEFINE_PER_CPU(unsigned long *, sdei_stack_normal_ptr); DEFINE_PER_CPU(unsigned long *, sdei_stack_critical_ptr); #endif +DECLARE_PER_CPU(unsigned long *, sdei_shadow_call_stack_normal_ptr); +DECLARE_PER_CPU(unsigned long *, sdei_shadow_call_stack_critical_ptr); + +#ifdef CONFIG_SHADOW_CALL_STACK +DEFINE_PER_CPU(unsigned long *, sdei_shadow_call_stack_normal_ptr); +DEFINE_PER_CPU(unsigned long *, sdei_shadow_call_stack_critical_ptr); +#endif + static void _free_sdei_stack(unsigned long * __percpu *ptr, int cpu) { unsigned long *p; @@ -48,13 +57,31 @@ static void _free_sdei_stack(unsigned long * __percpu *ptr, int cpu) } } +static void _free_sdei_scs(unsigned long * __percpu *ptr, int cpu) +{ + void *s; + + s = per_cpu(*ptr, cpu); + if (s) { + per_cpu(*ptr, cpu) = NULL; + scs_free(s); + } +} + static void free_sdei_stacks(void) { int cpu; for_each_possible_cpu(cpu) { - _free_sdei_stack(&sdei_stack_normal_ptr, cpu); - _free_sdei_stack(&sdei_stack_critical_ptr, cpu); + if (IS_ENABLED(CONFIG_VMAP_STACK)) { + _free_sdei_stack(&sdei_stack_normal_ptr, cpu); + _free_sdei_stack(&sdei_stack_critical_ptr, cpu); + } + + if (IS_ENABLED(CONFIG_SHADOW_CALL_STACK)) { + _free_sdei_scs(&sdei_shadow_call_stack_normal_ptr, cpu); + _free_sdei_scs(&sdei_shadow_call_stack_critical_ptr, cpu); + } } } @@ -70,18 +97,40 @@ static int _init_sdei_stack(unsigned long * __percpu *ptr, int cpu) return 0; } +static int _init_sdei_scs(unsigned long * __percpu *ptr, int cpu) +{ + void *s; + + s = scs_alloc(cpu_to_node(cpu)); + if (!s) + return -ENOMEM; + per_cpu(*ptr, cpu) = s; + + return 0; +} + static int init_sdei_stacks(void) { int cpu; int err = 0; for_each_possible_cpu(cpu) { - err = _init_sdei_stack(&sdei_stack_normal_ptr, cpu); - if (err) - break; - err = _init_sdei_stack(&sdei_stack_critical_ptr, cpu); - if (err) - break; + if (IS_ENABLED(CONFIG_VMAP_STACK)) { + err = _init_sdei_stack(&sdei_stack_normal_ptr, cpu); + if (err) + break; + err = _init_sdei_stack(&sdei_stack_critical_ptr, cpu); + if (err) + break; + } + if (IS_ENABLED(CONFIG_SHADOW_CALL_STACK)) { + err = _init_sdei_scs(&sdei_shadow_call_stack_normal_ptr, cpu); + if (err) + break; + err = _init_sdei_scs(&sdei_shadow_call_stack_critical_ptr, cpu); + if (err) + break; + } } if (err) @@ -133,10 +182,8 @@ unsigned long sdei_arch_get_entry_point(int conduit) return 0; } - if (IS_ENABLED(CONFIG_VMAP_STACK)) { - if (init_sdei_stacks()) - return 0; - } + if (init_sdei_stacks()) + return 0; sdei_exit_mode = (conduit == SMCCC_CONDUIT_HVC) ? SDEI_EXIT_HVC : SDEI_EXIT_SMC; diff --git a/include/linux/scs.h b/include/linux/scs.h index 2a506c2a16f4..18122d9e17ff 100644 --- a/include/linux/scs.h +++ b/include/linux/scs.h @@ -22,10 +22,6 @@ /* An illegal pointer value to mark the end of the shadow stack. */ #define SCS_END_MAGIC (0x5f6UL + POISON_POINTER_DELTA) -/* Allocate a static per-CPU shadow stack */ -#define DEFINE_SCS(name) \ - DEFINE_PER_CPU(unsigned long [SCS_SIZE/sizeof(long)], name) \ - #define task_scs(tsk) (task_thread_info(tsk)->scs_base) #define task_scs_sp(tsk) (task_thread_info(tsk)->scs_sp) -- 2.29.2.454.gaff20da3a2-goog