From patchwork Sat Jun 29 08:56:01 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jinjie Ruan X-Patchwork-Id: 13716857 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 98460C30658 for ; Sat, 29 Jun 2024 08:54:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:References:In-Reply-To:Message-ID:Date :Subject:To:From:Reply-To:Cc:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ImPVBDNbkahSXwd/Bo8HDxjnuXMaht9c73FUlMH8FAQ=; b=sp0swVFwQ26u86fd2PzFSqvPyZ uTwfGpbtN7NoZhXQGS/R3L4kdYdjaTWo+YcWq3zEQ89kjb4/mVONFOHx1KPE1Lfwc9F4XhYvEaWOM HJxAlVUcF4u0bdctth3SeLhL7aWTqJL/kNiMV116UdX1wGhLHtAcWkIBjffxXaeQ9yrcMhP+jo/v9 okznjDDuJA7Vzr2o6VO6qeImDFfhLY9SyiUWW+PZnWQNDV+64SVeTOfcxUco6upTxbc1SsfTZVjPx Wr5dsXmIIPvj8/WrTr3hCj+gy9UEULLsbGnDfzdIOfntFMGVl+KfmRLZ64ezQhenPvKRPUOjCJsyO GAGFtkLg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sNTqE-0000000G8sD-3i1G; Sat, 29 Jun 2024 08:53:54 +0000 Received: from szxga02-in.huawei.com ([45.249.212.188]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sNTpj-0000000G8gO-0RSS for linux-arm-kernel@lists.infradead.org; Sat, 29 Jun 2024 08:53:28 +0000 Received: from mail.maildlp.com (unknown [172.19.163.48]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4WB5g610HyznYQx; Sat, 29 Jun 2024 16:53:06 +0800 (CST) Received: from kwepemi100008.china.huawei.com (unknown [7.221.188.57]) by mail.maildlp.com (Postfix) with ESMTPS id B9F73180089; Sat, 29 Jun 2024 16:53:16 +0800 (CST) Received: from huawei.com (10.90.53.73) by kwepemi100008.china.huawei.com (7.221.188.57) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Sat, 29 Jun 2024 16:53:15 +0800 From: Jinjie Ruan To: , , , , , , , , , , , , , , , , , Subject: [PATCH v3 3/3] arm64: entry: Convert to generic entry Date: Sat, 29 Jun 2024 16:56:01 +0800 Message-ID: <20240629085601.470241-4-ruanjinjie@huawei.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240629085601.470241-1-ruanjinjie@huawei.com> References: <20240629085601.470241-1-ruanjinjie@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.90.53.73] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To kwepemi100008.china.huawei.com (7.221.188.57) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240629_015323_844540_40ABE636 X-CRM114-Status: GOOD ( 32.37 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Currently, x86, Riscv, Loongarch use the generic entry. Convert arm64 to use the generic entry infrastructure from kernel/entry/*. The generic entry makes maintainers' work easier and codes more elegant, which also removed duplicate 150+ LOC. The changes are below: - Remove TIF_SYSCALL_* flag, _TIF_WORK_MASK, _TIF_SYSCALL_WORK - Remove syscall_trace_enter/exit() and use generic one. - Remove *enter_from/exit_to_kernel_mode(), and wrap with generic irqentry_enter/exit(). - Remove *enter_from/exit_to_user_mode(), and wrap with generic irqentry_enter_from/exit_to_user_mode(). - Remove arm64_enter/exit_nmi() and use generic irqentry_nmi_enter/exit(). - Remove PREEMPT_DYNAMIC code, as generic entry will do it ok by implementing arch_irqentry_exit_need_resched(). Tested ok with following test cases on Qemu cortex-a53 and HiSilicon Kunpeng-920: - Run `perf top` command - Switch between different `dynamic preempt` mode - Use `pseudo nmi` - stress-ng CPU stress test. - MTE test case in Documentation/arch/arm64/memory-tagging-extension.rst and all test cases in tools/testing/selftests/arm64/mte/* (Only Qemu). Signed-off-by: Jinjie Ruan Tested-by: Jinjie Ruan Tested-by: Kees Cook --- v3: - Test the MTE test cases. - Handle forget_syscall() in arch_post_report_syscall_entry() - Rebased on the previous patch, so move the arch funcs to entry-common.h. - Change __always_inline() to inline for arch_enter_from_kernel_mode() and arch_exit_to_kernel_mode_prepare(), add inline for the other arch funcs. - Remove unused signal.h for entry-common.h. v2: - Add Tested-by. - Rebased on the refactored report_syscall() code. - Add comment for arch_prepare_report_syscall_exit(). - Update the commit message. - Adjust entry-common.h header file inclusion to alphabetical order. --- arch/arm64/Kconfig | 1 + arch/arm64/include/asm/entry-common.h | 172 ++++++++++++ arch/arm64/include/asm/syscall.h | 6 +- arch/arm64/include/asm/thread_info.h | 23 +- arch/arm64/kernel/entry-common.c | 368 +++++--------------------- arch/arm64/kernel/ptrace.c | 101 ------- arch/arm64/kernel/signal.c | 3 +- arch/arm64/kernel/syscall.c | 18 +- 8 files changed, 264 insertions(+), 428 deletions(-) create mode 100644 arch/arm64/include/asm/entry-common.h diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 5d91259ee7b5..e6ccc5ea06fe 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -138,6 +138,7 @@ config ARM64 select GENERIC_CPU_DEVICES select GENERIC_CPU_VULNERABILITIES select GENERIC_EARLY_IOREMAP + select GENERIC_ENTRY select GENERIC_IDLE_POLL_SETUP select GENERIC_IOREMAP select GENERIC_IRQ_IPI diff --git a/arch/arm64/include/asm/entry-common.h b/arch/arm64/include/asm/entry-common.h new file mode 100644 index 000000000000..a14d62b2eb69 --- /dev/null +++ b/arch/arm64/include/asm/entry-common.h @@ -0,0 +1,172 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _ASM_ARM64_ENTRY_COMMON_H +#define _ASM_ARM64_ENTRY_COMMON_H + +#include + +#include +#include +#include +#include + +enum ptrace_syscall_dir { + PTRACE_SYSCALL_ENTER = 0, + PTRACE_SYSCALL_EXIT, +}; + +#define ARCH_EXIT_TO_USER_MODE_WORK (_TIF_MTE_ASYNC_FAULT | _TIF_FOREIGN_FPSTATE) + +static __always_inline void arch_enter_from_user_mode(struct pt_regs *regs) +{ + mte_disable_tco_entry(current); +} + +#define arch_enter_from_user_mode arch_enter_from_user_mode + +static __always_inline void arch_exit_to_user_mode_work(struct pt_regs *regs, + unsigned long ti_work) +{ + if (ti_work & _TIF_MTE_ASYNC_FAULT) { + clear_thread_flag(TIF_MTE_ASYNC_FAULT); + send_sig_fault(SIGSEGV, SEGV_MTEAERR, (void __user *)NULL, current); + } + + if (ti_work & _TIF_FOREIGN_FPSTATE) + fpsimd_restore_current_state(); +} + +#define arch_exit_to_user_mode_work arch_exit_to_user_mode_work + +static inline void arch_exit_to_user_mode_prepare(struct pt_regs *regs, + unsigned long ti_work) +{ + local_daif_mask(); + mte_check_tfsr_exit(); +} + +#define arch_exit_to_user_mode_prepare arch_exit_to_user_mode_prepare + +static inline void arch_enter_from_kernel_mode(struct pt_regs *regs) +{ + mte_check_tfsr_entry(); + mte_disable_tco_entry(current); +} + +#define arch_enter_from_kernel_mode arch_enter_from_kernel_mode + +static inline void arch_exit_to_kernel_mode_prepare(struct pt_regs *regs) +{ + mte_check_tfsr_exit(); +} + +#define arch_exit_to_kernel_mode_prepare arch_exit_to_kernel_mode_prepare + +static inline bool arch_irqentry_exit_need_resched(void) +{ + /* + * DAIF.DA are cleared at the start of IRQ/FIQ handling, and when GIC + * priority masking is used the GIC irqchip driver will clear DAIF.IF + * using gic_arch_enable_irqs() for normal IRQs. If anything is set in + * DAIF we must have handled an NMI, so skip preemption. + */ + if (system_uses_irq_prio_masking() && read_sysreg(daif)) + return false; + + /* + * Preempting a task from an IRQ means we leave copies of PSTATE + * on the stack. cpufeature's enable calls may modify PSTATE, but + * resuming one of these preempted tasks would undo those changes. + * + * Only allow a task to be preempted once cpufeatures have been + * enabled. + */ + if (!system_capabilities_finalized()) + return false; + + return true; +} + +#define arch_irqentry_exit_need_resched arch_irqentry_exit_need_resched + +static inline unsigned long arch_prepare_report_syscall_entry(struct pt_regs *regs) +{ + unsigned long saved_reg; + int regno; + + /* + * We have some ABI weirdness here in the way that we handle syscall + * exit stops because we indicate whether or not the stop has been + * signalled from syscall entry or syscall exit by clobbering a general + * purpose register (ip/r12 for AArch32, x7 for AArch64) in the tracee + * and restoring its old value after the stop. This means that: + * + * - Any writes by the tracer to this register during the stop are + * ignored/discarded. + * + * - The actual value of the register is not available during the stop, + * so the tracer cannot save it and restore it later. + * + * - Syscall stops behave differently to seccomp and pseudo-step traps + * (the latter do not nobble any registers). + */ + regno = (is_compat_task() ? 12 : 7); + saved_reg = regs->regs[regno]; + regs->regs[regno] = PTRACE_SYSCALL_ENTER; + + return saved_reg; +} + +#define arch_prepare_report_syscall_entry arch_prepare_report_syscall_entry + +static inline void arch_post_report_syscall_entry(struct pt_regs *regs, + unsigned long saved_reg, long ret) +{ + int regno = (is_compat_task() ? 12 : 7); + + if (ret) + forget_syscall(regs); + + regs->regs[regno] = saved_reg; +} + +#define arch_post_report_syscall_entry arch_post_report_syscall_entry + +static inline unsigned long arch_prepare_report_syscall_exit(struct pt_regs *regs, + unsigned long work) +{ + unsigned long saved_reg; + int regno; + + /* See comment for arch_prepare_report_syscall_entry() */ + regno = (is_compat_task() ? 12 : 7); + saved_reg = regs->regs[regno]; + regs->regs[regno] = PTRACE_SYSCALL_EXIT; + + if (report_single_step(work)) { + /* + * Signal a pseudo-step exception since we are stepping but + * tracer modifications to the registers may have rewound the + * state machine. + */ + regs->regs[regno] = saved_reg; + } + + return saved_reg; +} + +#define arch_prepare_report_syscall_exit arch_prepare_report_syscall_exit + +static inline void arch_post_report_syscall_exit(struct pt_regs *regs, + unsigned long saved_reg, + unsigned long work) +{ + int regno = (is_compat_task() ? 12 : 7); + + if (!report_single_step(work)) + regs->regs[regno] = saved_reg; +} + +#define arch_post_report_syscall_exit arch_post_report_syscall_exit + +#endif /* _ASM_ARM64_ENTRY_COMMON_H */ diff --git a/arch/arm64/include/asm/syscall.h b/arch/arm64/include/asm/syscall.h index ab8e14b96f68..9891b15da4c3 100644 --- a/arch/arm64/include/asm/syscall.h +++ b/arch/arm64/include/asm/syscall.h @@ -85,7 +85,9 @@ static inline int syscall_get_arch(struct task_struct *task) return AUDIT_ARCH_AARCH64; } -int syscall_trace_enter(struct pt_regs *regs); -void syscall_trace_exit(struct pt_regs *regs); +static inline bool arch_syscall_is_vdso_sigreturn(struct pt_regs *regs) +{ + return false; +} #endif /* __ASM_SYSCALL_H */ diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h index e72a3bf9e563..ec5d74c53bf9 100644 --- a/arch/arm64/include/asm/thread_info.h +++ b/arch/arm64/include/asm/thread_info.h @@ -43,6 +43,7 @@ struct thread_info { void *scs_sp; #endif u32 cpu; + unsigned long syscall_work; /* SYSCALL_WORK_ flags */ }; #define thread_saved_pc(tsk) \ @@ -64,11 +65,6 @@ void arch_setup_new_exec(void); #define TIF_UPROBE 4 /* uprobe breakpoint or singlestep */ #define TIF_MTE_ASYNC_FAULT 5 /* MTE Asynchronous Tag Check Fault */ #define TIF_NOTIFY_SIGNAL 6 /* signal notifications exist */ -#define TIF_SYSCALL_TRACE 8 /* syscall trace active */ -#define TIF_SYSCALL_AUDIT 9 /* syscall auditing */ -#define TIF_SYSCALL_TRACEPOINT 10 /* syscall tracepoint for ftrace */ -#define TIF_SECCOMP 11 /* syscall secure computing */ -#define TIF_SYSCALL_EMU 12 /* syscall emulation active */ #define TIF_MEMDIE 18 /* is terminating due to OOM killer */ #define TIF_FREEZE 19 #define TIF_RESTORE_SIGMASK 20 @@ -86,27 +82,12 @@ void arch_setup_new_exec(void); #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) #define _TIF_FOREIGN_FPSTATE (1 << TIF_FOREIGN_FPSTATE) -#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) -#define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) -#define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT) -#define _TIF_SECCOMP (1 << TIF_SECCOMP) -#define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU) -#define _TIF_UPROBE (1 << TIF_UPROBE) -#define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP) +#define _TIF_UPROBE (1 << TIF_UPROBE) #define _TIF_32BIT (1 << TIF_32BIT) #define _TIF_SVE (1 << TIF_SVE) #define _TIF_MTE_ASYNC_FAULT (1 << TIF_MTE_ASYNC_FAULT) #define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL) -#define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ - _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \ - _TIF_UPROBE | _TIF_MTE_ASYNC_FAULT | \ - _TIF_NOTIFY_SIGNAL) - -#define _TIF_SYSCALL_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \ - _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \ - _TIF_SYSCALL_EMU) - #ifdef CONFIG_SHADOW_CALL_STACK #define INIT_SCS \ .scs_base = init_shadow_call_stack, \ diff --git a/arch/arm64/kernel/entry-common.c b/arch/arm64/kernel/entry-common.c index b77a15955f28..ac61aeb93933 100644 --- a/arch/arm64/kernel/entry-common.c +++ b/arch/arm64/kernel/entry-common.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include @@ -28,201 +29,15 @@ #include #include -/* - * Handle IRQ/context state management when entering from kernel mode. - * Before this function is called it is not safe to call regular kernel code, - * instrumentable code, or any code which may trigger an exception. - * - * This is intended to match the logic in irqentry_enter(), handling the kernel - * mode transitions only. - */ -static __always_inline void __enter_from_kernel_mode(struct pt_regs *regs) -{ - regs->exit_rcu = false; - - if (!IS_ENABLED(CONFIG_TINY_RCU) && is_idle_task(current)) { - lockdep_hardirqs_off(CALLER_ADDR0); - ct_irq_enter(); - trace_hardirqs_off_finish(); - - regs->exit_rcu = true; - return; - } - - lockdep_hardirqs_off(CALLER_ADDR0); - rcu_irq_enter_check_tick(); - trace_hardirqs_off_finish(); -} - -static void noinstr enter_from_kernel_mode(struct pt_regs *regs) -{ - __enter_from_kernel_mode(regs); - mte_check_tfsr_entry(); - mte_disable_tco_entry(current); -} - -/* - * Handle IRQ/context state management when exiting to kernel mode. - * After this function returns it is not safe to call regular kernel code, - * instrumentable code, or any code which may trigger an exception. - * - * This is intended to match the logic in irqentry_exit(), handling the kernel - * mode transitions only, and with preemption handled elsewhere. - */ -static __always_inline void __exit_to_kernel_mode(struct pt_regs *regs) -{ - lockdep_assert_irqs_disabled(); - - if (interrupts_enabled(regs)) { - if (regs->exit_rcu) { - trace_hardirqs_on_prepare(); - lockdep_hardirqs_on_prepare(); - ct_irq_exit(); - lockdep_hardirqs_on(CALLER_ADDR0); - return; - } - - trace_hardirqs_on(); - } else { - if (regs->exit_rcu) - ct_irq_exit(); - } -} - -static void noinstr exit_to_kernel_mode(struct pt_regs *regs) -{ - mte_check_tfsr_exit(); - __exit_to_kernel_mode(regs); -} - -/* - * Handle IRQ/context state management when entering from user mode. - * Before this function is called it is not safe to call regular kernel code, - * instrumentable code, or any code which may trigger an exception. - */ -static __always_inline void __enter_from_user_mode(void) +static __always_inline void exit_to_user_mode_wrapper(struct pt_regs *regs) { - lockdep_hardirqs_off(CALLER_ADDR0); - CT_WARN_ON(ct_state() != CONTEXT_USER); - user_exit_irqoff(); - trace_hardirqs_off_finish(); - mte_disable_tco_entry(current); -} - -static __always_inline void enter_from_user_mode(struct pt_regs *regs) -{ - __enter_from_user_mode(); -} - -/* - * Handle IRQ/context state management when exiting to user mode. - * After this function returns it is not safe to call regular kernel code, - * instrumentable code, or any code which may trigger an exception. - */ -static __always_inline void __exit_to_user_mode(void) -{ - trace_hardirqs_on_prepare(); - lockdep_hardirqs_on_prepare(); - user_enter_irqoff(); - lockdep_hardirqs_on(CALLER_ADDR0); -} - -static void do_notify_resume(struct pt_regs *regs, unsigned long thread_flags) -{ - do { - local_irq_enable(); - - if (thread_flags & _TIF_NEED_RESCHED) - schedule(); - - if (thread_flags & _TIF_UPROBE) - uprobe_notify_resume(regs); - - if (thread_flags & _TIF_MTE_ASYNC_FAULT) { - clear_thread_flag(TIF_MTE_ASYNC_FAULT); - send_sig_fault(SIGSEGV, SEGV_MTEAERR, - (void __user *)NULL, current); - } - - if (thread_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) - do_signal(regs); - - if (thread_flags & _TIF_NOTIFY_RESUME) - resume_user_mode_work(regs); - - if (thread_flags & _TIF_FOREIGN_FPSTATE) - fpsimd_restore_current_state(); - - local_irq_disable(); - thread_flags = read_thread_flags(); - } while (thread_flags & _TIF_WORK_MASK); -} - -static __always_inline void exit_to_user_mode_prepare(struct pt_regs *regs) -{ - unsigned long flags; - local_irq_disable(); - - flags = read_thread_flags(); - if (unlikely(flags & _TIF_WORK_MASK)) - do_notify_resume(regs, flags); - - local_daif_mask(); - - lockdep_sys_exit(); -} - -static __always_inline void exit_to_user_mode(struct pt_regs *regs) -{ - exit_to_user_mode_prepare(regs); - mte_check_tfsr_exit(); - __exit_to_user_mode(); + irqentry_exit_to_user_mode(regs); } asmlinkage void noinstr asm_exit_to_user_mode(struct pt_regs *regs) { - exit_to_user_mode(regs); -} - -/* - * Handle IRQ/context state management when entering an NMI from user/kernel - * mode. Before this function is called it is not safe to call regular kernel - * code, instrumentable code, or any code which may trigger an exception. - */ -static void noinstr arm64_enter_nmi(struct pt_regs *regs) -{ - regs->lockdep_hardirqs = lockdep_hardirqs_enabled(); - - __nmi_enter(); - lockdep_hardirqs_off(CALLER_ADDR0); - lockdep_hardirq_enter(); - ct_nmi_enter(); - - trace_hardirqs_off_finish(); - ftrace_nmi_enter(); -} - -/* - * Handle IRQ/context state management when exiting an NMI from user/kernel - * mode. After this function returns it is not safe to call regular kernel - * code, instrumentable code, or any code which may trigger an exception. - */ -static void noinstr arm64_exit_nmi(struct pt_regs *regs) -{ - bool restore = regs->lockdep_hardirqs; - - ftrace_nmi_exit(); - if (restore) { - trace_hardirqs_on_prepare(); - lockdep_hardirqs_on_prepare(); - } - - ct_nmi_exit(); - lockdep_hardirq_exit(); - if (restore) - lockdep_hardirqs_on(CALLER_ADDR0); - __nmi_exit(); + exit_to_user_mode_wrapper(regs); } /* @@ -259,48 +74,6 @@ static void noinstr arm64_exit_el1_dbg(struct pt_regs *regs) lockdep_hardirqs_on(CALLER_ADDR0); } -#ifdef CONFIG_PREEMPT_DYNAMIC -DEFINE_STATIC_KEY_TRUE(sk_dynamic_irqentry_exit_cond_resched); -#define need_irq_preemption() \ - (static_branch_unlikely(&sk_dynamic_irqentry_exit_cond_resched)) -#else -#define need_irq_preemption() (IS_ENABLED(CONFIG_PREEMPTION)) -#endif - -static void __sched arm64_preempt_schedule_irq(void) -{ - if (!need_irq_preemption()) - return; - - /* - * Note: thread_info::preempt_count includes both thread_info::count - * and thread_info::need_resched, and is not equivalent to - * preempt_count(). - */ - if (READ_ONCE(current_thread_info()->preempt_count) != 0) - return; - - /* - * DAIF.DA are cleared at the start of IRQ/FIQ handling, and when GIC - * priority masking is used the GIC irqchip driver will clear DAIF.IF - * using gic_arch_enable_irqs() for normal IRQs. If anything is set in - * DAIF we must have handled an NMI, so skip preemption. - */ - if (system_uses_irq_prio_masking() && read_sysreg(daif)) - return; - - /* - * Preempting a task from an IRQ means we leave copies of PSTATE - * on the stack. cpufeature's enable calls may modify PSTATE, but - * resuming one of these preempted tasks would undo those changes. - * - * Only allow a task to be preempted once cpufeatures have been - * enabled. - */ - if (system_capabilities_finalized()) - preempt_schedule_irq(); -} - static void do_interrupt_handler(struct pt_regs *regs, void (*handler)(struct pt_regs *)) { @@ -320,7 +93,7 @@ extern void (*handle_arch_fiq)(struct pt_regs *); static void noinstr __panic_unhandled(struct pt_regs *regs, const char *vector, unsigned long esr) { - arm64_enter_nmi(regs); + irqentry_nmi_enter(regs); console_verbose(); @@ -426,41 +199,43 @@ UNHANDLED(el1t, 64, error) static void noinstr el1_abort(struct pt_regs *regs, unsigned long esr) { unsigned long far = read_sysreg(far_el1); + irqentry_state_t state = irqentry_enter(regs); - enter_from_kernel_mode(regs); local_daif_inherit(regs); do_mem_abort(far, esr, regs); local_daif_mask(); - exit_to_kernel_mode(regs); + irqentry_exit(regs, state); } static void noinstr el1_pc(struct pt_regs *regs, unsigned long esr) { unsigned long far = read_sysreg(far_el1); + irqentry_state_t state = irqentry_enter(regs); - enter_from_kernel_mode(regs); local_daif_inherit(regs); do_sp_pc_abort(far, esr, regs); local_daif_mask(); - exit_to_kernel_mode(regs); + irqentry_exit(regs, state); } static void noinstr el1_undef(struct pt_regs *regs, unsigned long esr) { - enter_from_kernel_mode(regs); + irqentry_state_t state = irqentry_enter(regs); + local_daif_inherit(regs); do_el1_undef(regs, esr); local_daif_mask(); - exit_to_kernel_mode(regs); + irqentry_exit(regs, state); } static void noinstr el1_bti(struct pt_regs *regs, unsigned long esr) { - enter_from_kernel_mode(regs); + irqentry_state_t state = irqentry_enter(regs); + local_daif_inherit(regs); do_el1_bti(regs, esr); local_daif_mask(); - exit_to_kernel_mode(regs); + irqentry_exit(regs, state); } static void noinstr el1_dbg(struct pt_regs *regs, unsigned long esr) @@ -475,11 +250,12 @@ static void noinstr el1_dbg(struct pt_regs *regs, unsigned long esr) static void noinstr el1_fpac(struct pt_regs *regs, unsigned long esr) { - enter_from_kernel_mode(regs); + irqentry_state_t state = irqentry_enter(regs); + local_daif_inherit(regs); do_el1_fpac(regs, esr); local_daif_mask(); - exit_to_kernel_mode(regs); + irqentry_exit(regs, state); } asmlinkage void noinstr el1h_64_sync_handler(struct pt_regs *regs) @@ -522,23 +298,22 @@ asmlinkage void noinstr el1h_64_sync_handler(struct pt_regs *regs) static __always_inline void __el1_pnmi(struct pt_regs *regs, void (*handler)(struct pt_regs *)) { - arm64_enter_nmi(regs); + irqentry_state_t state = irqentry_nmi_enter(regs); + do_interrupt_handler(regs, handler); - arm64_exit_nmi(regs); + irqentry_nmi_exit(regs, state); } static __always_inline void __el1_irq(struct pt_regs *regs, void (*handler)(struct pt_regs *)) { - enter_from_kernel_mode(regs); + irqentry_state_t state = irqentry_enter(regs); irq_enter_rcu(); do_interrupt_handler(regs, handler); irq_exit_rcu(); - arm64_preempt_schedule_irq(); - - exit_to_kernel_mode(regs); + irqentry_exit(regs, state); } static void noinstr el1_interrupt(struct pt_regs *regs, void (*handler)(struct pt_regs *)) @@ -564,21 +339,22 @@ asmlinkage void noinstr el1h_64_fiq_handler(struct pt_regs *regs) asmlinkage void noinstr el1h_64_error_handler(struct pt_regs *regs) { unsigned long esr = read_sysreg(esr_el1); + irqentry_state_t state; local_daif_restore(DAIF_ERRCTX); - arm64_enter_nmi(regs); + state = irqentry_nmi_enter(regs); do_serror(regs, esr); - arm64_exit_nmi(regs); + irqentry_nmi_exit(regs, state); } static void noinstr el0_da(struct pt_regs *regs, unsigned long esr) { unsigned long far = read_sysreg(far_el1); - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); do_mem_abort(far, esr, regs); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_ia(struct pt_regs *regs, unsigned long esr) @@ -593,50 +369,50 @@ static void noinstr el0_ia(struct pt_regs *regs, unsigned long esr) if (!is_ttbr0_addr(far)) arm64_apply_bp_hardening(); - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); do_mem_abort(far, esr, regs); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_fpsimd_acc(struct pt_regs *regs, unsigned long esr) { - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); do_fpsimd_acc(esr, regs); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_sve_acc(struct pt_regs *regs, unsigned long esr) { - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); do_sve_acc(esr, regs); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_sme_acc(struct pt_regs *regs, unsigned long esr) { - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); do_sme_acc(esr, regs); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_fpsimd_exc(struct pt_regs *regs, unsigned long esr) { - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); do_fpsimd_exc(esr, regs); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_sys(struct pt_regs *regs, unsigned long esr) { - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); do_el0_sys(esr, regs); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_pc(struct pt_regs *regs, unsigned long esr) @@ -646,50 +422,50 @@ static void noinstr el0_pc(struct pt_regs *regs, unsigned long esr) if (!is_ttbr0_addr(instruction_pointer(regs))) arm64_apply_bp_hardening(); - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); do_sp_pc_abort(far, esr, regs); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_sp(struct pt_regs *regs, unsigned long esr) { - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); do_sp_pc_abort(regs->sp, esr, regs); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_undef(struct pt_regs *regs, unsigned long esr) { - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); do_el0_undef(regs, esr); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_bti(struct pt_regs *regs) { - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); do_el0_bti(regs); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_mops(struct pt_regs *regs, unsigned long esr) { - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); do_el0_mops(regs, esr); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_inv(struct pt_regs *regs, unsigned long esr) { - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); bad_el0_sync(regs, 0, esr); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_dbg(struct pt_regs *regs, unsigned long esr) @@ -697,28 +473,28 @@ static void noinstr el0_dbg(struct pt_regs *regs, unsigned long esr) /* Only watchpoints write FAR_EL1, otherwise its UNKNOWN */ unsigned long far = read_sysreg(far_el1); - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); do_debug_exception(far, esr, regs); local_daif_restore(DAIF_PROCCTX); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_svc(struct pt_regs *regs) { - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); cortex_a76_erratum_1463225_svc_handler(); fp_user_discard(); local_daif_restore(DAIF_PROCCTX); do_el0_svc(regs); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_fpac(struct pt_regs *regs, unsigned long esr) { - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); do_el0_fpac(regs, esr); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } asmlinkage void noinstr el0t_64_sync_handler(struct pt_regs *regs) @@ -783,7 +559,7 @@ asmlinkage void noinstr el0t_64_sync_handler(struct pt_regs *regs) static void noinstr el0_interrupt(struct pt_regs *regs, void (*handler)(struct pt_regs *)) { - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); write_sysreg(DAIF_PROCCTX_NOIRQ, daif); @@ -794,7 +570,7 @@ static void noinstr el0_interrupt(struct pt_regs *regs, do_interrupt_handler(regs, handler); irq_exit_rcu(); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr __el0_irq_handler_common(struct pt_regs *regs) @@ -820,14 +596,15 @@ asmlinkage void noinstr el0t_64_fiq_handler(struct pt_regs *regs) static void noinstr __el0_error_handler_common(struct pt_regs *regs) { unsigned long esr = read_sysreg(esr_el1); + irqentry_state_t state_nmi; - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_ERRCTX); - arm64_enter_nmi(regs); + state_nmi = irqentry_nmi_enter(regs); do_serror(regs, esr); - arm64_exit_nmi(regs); + irqentry_nmi_exit(regs, state_nmi); local_daif_restore(DAIF_PROCCTX); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } asmlinkage void noinstr el0t_64_error_handler(struct pt_regs *regs) @@ -838,19 +615,19 @@ asmlinkage void noinstr el0t_64_error_handler(struct pt_regs *regs) #ifdef CONFIG_COMPAT static void noinstr el0_cp15(struct pt_regs *regs, unsigned long esr) { - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); local_daif_restore(DAIF_PROCCTX); do_el0_cp15(esr, regs); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } static void noinstr el0_svc_compat(struct pt_regs *regs) { - enter_from_user_mode(regs); + irqentry_enter_from_user_mode(regs); cortex_a76_erratum_1463225_svc_handler(); local_daif_restore(DAIF_PROCCTX); do_el0_svc_compat(regs); - exit_to_user_mode(regs); + exit_to_user_mode_wrapper(regs); } asmlinkage void noinstr el0t_32_sync_handler(struct pt_regs *regs) @@ -924,7 +701,7 @@ asmlinkage void noinstr __noreturn handle_bad_stack(struct pt_regs *regs) unsigned long esr = read_sysreg(esr_el1); unsigned long far = read_sysreg(far_el1); - arm64_enter_nmi(regs); + irqentry_nmi_enter(regs); panic_bad_stack(regs, esr, far); } #endif /* CONFIG_VMAP_STACK */ @@ -933,6 +710,7 @@ asmlinkage void noinstr __noreturn handle_bad_stack(struct pt_regs *regs) asmlinkage noinstr unsigned long __sdei_handler(struct pt_regs *regs, struct sdei_registered_event *arg) { + irqentry_state_t state; unsigned long ret; /* @@ -957,9 +735,9 @@ __sdei_handler(struct pt_regs *regs, struct sdei_registered_event *arg) else if (cpu_has_pan()) set_pstate_pan(0); - arm64_enter_nmi(regs); + state = irqentry_nmi_enter(regs); ret = do_sdei_event(regs, arg); - arm64_exit_nmi(regs); + irqentry_nmi_exit(regs, state); return ret; } diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index 60fd85d5119d..9cc0f450fa76 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -41,9 +41,6 @@ #include #include -#define CREATE_TRACE_POINTS -#include - struct pt_regs_offset { const char *name; int offset; @@ -2179,104 +2176,6 @@ long arch_ptrace(struct task_struct *child, long request, return ptrace_request(child, request, addr, data); } -enum ptrace_syscall_dir { - PTRACE_SYSCALL_ENTER = 0, - PTRACE_SYSCALL_EXIT, -}; - -static void report_syscall_enter(struct pt_regs *regs) -{ - int regno; - unsigned long saved_reg; - - /* - * We have some ABI weirdness here in the way that we handle syscall - * exit stops because we indicate whether or not the stop has been - * signalled from syscall entry or syscall exit by clobbering a general - * purpose register (ip/r12 for AArch32, x7 for AArch64) in the tracee - * and restoring its old value after the stop. This means that: - * - * - Any writes by the tracer to this register during the stop are - * ignored/discarded. - * - * - The actual value of the register is not available during the stop, - * so the tracer cannot save it and restore it later. - * - * - Syscall stops behave differently to seccomp and pseudo-step traps - * (the latter do not nobble any registers). - */ - regno = (is_compat_task() ? 12 : 7); - saved_reg = regs->regs[regno]; - regs->regs[regno] = PTRACE_SYSCALL_ENTER; - - if (ptrace_report_syscall_entry(regs)) - forget_syscall(regs); - regs->regs[regno] = saved_reg; -} - -static void report_syscall_exit(struct pt_regs *regs) -{ - int regno; - unsigned long saved_reg; - - /* See comment for report_syscall_enter() */ - regno = (is_compat_task() ? 12 : 7); - saved_reg = regs->regs[regno]; - regs->regs[regno] = PTRACE_SYSCALL_EXIT; - - if (!test_thread_flag(TIF_SINGLESTEP)) { - ptrace_report_syscall_exit(regs, 0); - regs->regs[regno] = saved_reg; - } else { - regs->regs[regno] = saved_reg; - - /* - * Signal a pseudo-step exception since we are stepping but - * tracer modifications to the registers may have rewound the - * state machine. - */ - ptrace_report_syscall_exit(regs, 1); - } -} - -int syscall_trace_enter(struct pt_regs *regs) -{ - unsigned long flags = read_thread_flags(); - - if (flags & (_TIF_SYSCALL_EMU | _TIF_SYSCALL_TRACE)) { - report_syscall_enter(regs); - if (flags & _TIF_SYSCALL_EMU) - return NO_SYSCALL; - } - - /* Do the secure computing after ptrace; failures should be fast. */ - if (secure_computing() == -1) - return NO_SYSCALL; - - if (test_thread_flag(TIF_SYSCALL_TRACEPOINT)) - trace_sys_enter(regs, regs->syscallno); - - audit_syscall_entry(regs->syscallno, regs->orig_x0, regs->regs[1], - regs->regs[2], regs->regs[3]); - - return regs->syscallno; -} - -void syscall_trace_exit(struct pt_regs *regs) -{ - unsigned long flags = read_thread_flags(); - - audit_syscall_exit(regs); - - if (flags & _TIF_SYSCALL_TRACEPOINT) - trace_sys_exit(regs, syscall_get_return_value(current, regs)); - - if (flags & (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP)) - report_syscall_exit(regs); - - rseq_syscall(regs); -} - /* * SPSR_ELx bits which are always architecturally RES0 per ARM DDI 0487D.a. * We permit userspace to set SSBS (AArch64 bit 12, AArch32 bit 23) which is diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c index 4a77f4976e11..2982f6db6d96 100644 --- a/arch/arm64/kernel/signal.c +++ b/arch/arm64/kernel/signal.c @@ -19,6 +19,7 @@ #include #include #include +#include #include #include @@ -1266,7 +1267,7 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) * the kernel can handle, and then we build all the user-level signal handling * stack-frames in one go after that. */ -void do_signal(struct pt_regs *regs) +void arch_do_signal_or_restart(struct pt_regs *regs) { unsigned long continue_addr = 0, restart_addr = 0; int retval = 0; diff --git a/arch/arm64/kernel/syscall.c b/arch/arm64/kernel/syscall.c index ad198262b981..160ac9d15c27 100644 --- a/arch/arm64/kernel/syscall.c +++ b/arch/arm64/kernel/syscall.c @@ -7,6 +7,7 @@ #include #include #include +#include #include #include @@ -66,14 +67,15 @@ static void invoke_syscall(struct pt_regs *regs, unsigned int scno, choose_random_kstack_offset(get_random_u16() & 0x1FF); } -static inline bool has_syscall_work(unsigned long flags) +static inline bool has_syscall_work(unsigned long work) { - return unlikely(flags & _TIF_SYSCALL_WORK); + return unlikely(work & SYSCALL_WORK_ENTER); } static void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr, const syscall_fn_t syscall_table[]) { + unsigned long work = READ_ONCE(current_thread_info()->syscall_work); unsigned long flags = read_thread_flags(); regs->orig_x0 = regs->regs[0]; @@ -107,7 +109,7 @@ static void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr, return; } - if (has_syscall_work(flags)) { + if (has_syscall_work(work)) { /* * The de-facto standard way to skip a system call using ptrace * is to set the system call to -1 (NO_SYSCALL) and set x0 to a @@ -125,7 +127,7 @@ static void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr, */ if (scno == NO_SYSCALL) syscall_set_return_value(current, regs, -ENOSYS, 0); - scno = syscall_trace_enter(regs); + scno = syscall_trace_enter(regs, regs->syscallno, work); if (scno == NO_SYSCALL) goto trace_exit; } @@ -137,14 +139,14 @@ static void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr, * check again. However, if we were tracing entry, then we always trace * exit regardless, as the old entry assembly did. */ - if (!has_syscall_work(flags) && !IS_ENABLED(CONFIG_DEBUG_RSEQ)) { - flags = read_thread_flags(); - if (!has_syscall_work(flags) && !(flags & _TIF_SINGLESTEP)) + if (!has_syscall_work(work) && !IS_ENABLED(CONFIG_DEBUG_RSEQ)) { + work = READ_ONCE(current_thread_info()->syscall_work); + if (!has_syscall_work(work) && !report_single_step(work)) return; } trace_exit: - syscall_trace_exit(regs); + syscall_exit_work(regs, work); } void do_el0_svc(struct pt_regs *regs)