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=-20.4 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 510D7C388F9 for ; Thu, 22 Oct 2020 20:24:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D06612462E for ; Thu, 22 Oct 2020 20:24:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="lIVRXpl0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S371567AbgJVUYL (ORCPT ); Thu, 22 Oct 2020 16:24:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60196 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S371551AbgJVUYH (ORCPT ); Thu, 22 Oct 2020 16:24:07 -0400 Received: from mail-qk1-x74a.google.com (mail-qk1-x74a.google.com [IPv6:2607:f8b0:4864:20::74a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B9C2C0613CE for ; Thu, 22 Oct 2020 13:24:07 -0700 (PDT) Received: by mail-qk1-x74a.google.com with SMTP id v190so1865821qki.21 for ; Thu, 22 Oct 2020 13:24:07 -0700 (PDT) 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=HdaEzwW485tOauxqLOPFR2PJAF06evpL8oosipyb9N4=; b=lIVRXpl0VYnVqLZkN59z5l6EB0oiuWQYvHmtdZOvGgLY1DycgKA7bfxTZolWpxPysq uPY8ErFQua5rvGjajXi6TAbgoI+aSLhe+N0PiuOUihjVjNHAr6XBZZBkcp4bE1Mz0GhR GEtMgSqvSMjP/EwI1/XRXHH8oGjnjguQF+Clr8AEuqdilMbhOh3g9xv3zhrBB+ie2nOx wTAhHLvzGhCQHGF+cwHgEnU9ZjnxkzKAvzo5ubuMb8Ewn/MfnxBk2c/zGC73G7usVhfz Nps59f9AEndYLXnnbequ/7aJ9P7jZbalqks1vwtStvcrVyKT61A/8SIBcJUasp6wWI9k hvug== 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=HdaEzwW485tOauxqLOPFR2PJAF06evpL8oosipyb9N4=; b=BG2derx58XzoqKyDLpz9xs44XnwjmRXNoOP5fqDD8lHLLVV2ipQD6U2kz5sD98pzCD CViQKG7MEH+DtV7Eq1F9VbPWH64UyTXOcexeAAozFUxdgKQzSc1R5rQV2khFKovBu8WJ lXSw7EcEDk8U0at53uXRyFrI9+DJpUzxBhdXq2aWyqGu64xffcTZ455EC3iPpBw/r7b4 ctTpcMqK9nEt9d7KKOS1HJJrps9q14JmHlrP8mQ1alNlbxi/9LLv/64Kq0AHbxzHGsxw 0GdByiI2t9WyaKHw7RRIHbcA+OvKRYpUsHlLWWZ5B3vaxw0uYXlEzFrYRQAI34lwJXtH Wo3w== X-Gm-Message-State: AOAM533Y2cI3voJPiwScv+UyMFAJZ0By5Rn3HOT4/XnVNVJ8ZvfFrpN2 SgYhVfv7gHUrKlsDycUMY4WXQGI4/3TTSt4Ta1Y= X-Google-Smtp-Source: ABdhPJz/Sh6UUI+3VBKbiRt9YnloPvsrz1cGe/jkO3/yS7Oyq21RzG7T9W9c0Oa0QjO69qc+dVzDOd5vcpOAQ+D1hLQ= 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:a0c:e512:: with SMTP id l18mr4207892qvm.31.1603398246632; Thu, 22 Oct 2020 13:24:06 -0700 (PDT) Date: Thu, 22 Oct 2020 13:23:55 -0700 In-Reply-To: <20201022202355.3529836-1-samitolvanen@google.com> Message-Id: <20201022202355.3529836-3-samitolvanen@google.com> Mime-Version: 1.0 References: <20201022202355.3529836-1-samitolvanen@google.com> X-Mailer: git-send-email 2.29.0.rc1.297.gfa9743e501-goog Subject: [PATCH 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/include/asm/scs.h | 21 ++++++++++- arch/arm64/kernel/entry.S | 6 ++-- arch/arm64/kernel/irq.c | 2 ++ arch/arm64/kernel/scs.c | 67 +++++++++++++++++++++++++++++++++--- arch/arm64/kernel/sdei.c | 7 ++++ include/linux/scs.h | 8 ++--- kernel/scs.c | 4 +-- 7 files changed, 101 insertions(+), 14 deletions(-) diff --git a/arch/arm64/include/asm/scs.h b/arch/arm64/include/asm/scs.h index eaa2cd92e4c1..e9d2c3e67ff9 100644 --- a/arch/arm64/include/asm/scs.h +++ b/arch/arm64/include/asm/scs.h @@ -24,6 +24,25 @@ .endm #endif /* CONFIG_SHADOW_CALL_STACK */ -#endif /* __ASSEMBLY __ */ +#else /* __ASSEMBLY__ */ + +#include + +#ifdef CONFIG_SHADOW_CALL_STACK + +extern void scs_init_irq(void); + +extern void scs_free_sdei(void); +extern int scs_init_sdei(void); + +#else + +static inline void scs_init_irq(void) {} +static inline void scs_free_sdei(void) {} +static inline int scs_init_sdei(void) { return -EOPNOTSUPP; } + +#endif + +#endif /* __ASSEMBLY__ */ #endif /* _ASM_SCS_H */ diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index f30007dff35f..0f76fe8142e4 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -438,7 +438,7 @@ 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: @@ -1094,9 +1094,9 @@ 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..54ba3725bc0e 100644 --- a/arch/arm64/kernel/irq.c +++ b/arch/arm64/kernel/irq.c @@ -20,6 +20,7 @@ #include #include #include +#include #include /* Only access this in an NMI enter/exit */ @@ -54,6 +55,7 @@ static void init_irq_stacks(void) void __init init_IRQ(void) { init_irq_stacks(); + scs_init_irq(); 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 index e8f7ff45dd8f..f85cebf8122a 100644 --- a/arch/arm64/kernel/scs.c +++ b/arch/arm64/kernel/scs.c @@ -6,11 +6,70 @@ */ #include -#include +#include -DEFINE_SCS(irq_shadow_call_stack); +DEFINE_PER_CPU(unsigned long *, irq_shadow_call_stack_ptr); + +DECLARE_PER_CPU(unsigned long *, sdei_shadow_call_stack_normal_ptr); +DECLARE_PER_CPU(unsigned long *, sdei_shadow_call_stack_critical_ptr); #ifdef CONFIG_ARM_SDE_INTERFACE -DEFINE_SCS(sdei_shadow_call_stack_normal); -DEFINE_SCS(sdei_shadow_call_stack_critical); +DEFINE_PER_CPU(unsigned long *, sdei_shadow_call_stack_normal_ptr); +DEFINE_PER_CPU(unsigned long *, sdei_shadow_call_stack_critical_ptr); #endif + +void scs_init_irq(void) +{ + int cpu; + + for_each_possible_cpu(cpu) + per_cpu(irq_shadow_call_stack_ptr, cpu) = + scs_alloc(cpu_to_node(cpu)); +} + + +void scs_free_sdei(void) +{ + int cpu; + void *s; + + if (!IS_ENABLED(CONFIG_ARM_SDE_INTERFACE)) + return; + + for_each_possible_cpu(cpu) { + s = per_cpu(sdei_shadow_call_stack_normal_ptr, cpu); + if (s) + scs_free(s); + + s = per_cpu(sdei_shadow_call_stack_critical_ptr, cpu); + if (s) + scs_free(s); + } +} + +int scs_init_sdei(void) +{ + int cpu; + void *s; + + if (!IS_ENABLED(CONFIG_ARM_SDE_INTERFACE)) + return 0; + + for_each_possible_cpu(cpu) { + s = scs_alloc(cpu_to_node(cpu)); + if (!s) + goto err; + per_cpu(sdei_shadow_call_stack_normal_ptr, cpu) = s; + + s = scs_alloc(cpu_to_node(cpu)); + if (!s) + goto err; + per_cpu(sdei_shadow_call_stack_critical_ptr, cpu) = s; + } + + return 0; + +err: + scs_free_sdei(); + return -ENOMEM; +} diff --git a/arch/arm64/kernel/sdei.c b/arch/arm64/kernel/sdei.c index 7689f2031c0c..04519a7cb51d 100644 --- a/arch/arm64/kernel/sdei.c +++ b/arch/arm64/kernel/sdei.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include #include @@ -138,6 +139,12 @@ unsigned long sdei_arch_get_entry_point(int conduit) return 0; } + if (scs_init_sdei()) { + if (IS_ENABLED(CONFIG_VMAP_STACK)) + free_sdei_stacks(); + return 0; + } + sdei_exit_mode = (conduit == SMCCC_CONDUIT_HVC) ? SDEI_EXIT_HVC : SDEI_EXIT_SMC; #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 diff --git a/include/linux/scs.h b/include/linux/scs.h index 86e3c4b7b714..6b35a83576d4 100644 --- a/include/linux/scs.h +++ b/include/linux/scs.h @@ -21,13 +21,11 @@ /* 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) +void *scs_alloc(int node); +void scs_free(void *s); void scs_init(void); int scs_prepare(struct task_struct *tsk, int node); void scs_release(struct task_struct *tsk); @@ -56,6 +54,8 @@ static inline bool task_scs_end_corrupted(struct task_struct *tsk) #else /* CONFIG_SHADOW_CALL_STACK */ +static inline void *scs_alloc(int node) { return NULL; } +static inline void scs_free(void *s) {} static inline void scs_init(void) {} static inline void scs_task_reset(struct task_struct *tsk) {} static inline int scs_prepare(struct task_struct *tsk, int node) { return 0; } diff --git a/kernel/scs.c b/kernel/scs.c index 2136edba548d..8df4a92cd939 100644 --- a/kernel/scs.c +++ b/kernel/scs.c @@ -24,7 +24,7 @@ static void __scs_account(void *s, int account) #define NR_CACHED_SCS 2 static DEFINE_PER_CPU(void *, scs_cache[NR_CACHED_SCS]); -static void *scs_alloc(int node) +void *scs_alloc(int node) { int i; void *s; @@ -63,7 +63,7 @@ static void *scs_alloc(int node) return s; } -static void scs_free(void *s) +void scs_free(void *s) { int i; -- 2.29.0.rc1.297.gfa9743e501-goog