Message-ID: <20240627081209.3511918-4-ruanjinjie@huawei.com>
Date: Thu, 27 Jun 2024 16:12:09 +0800
From: Jinjie Ruan <ruanjinjie@...wei.com>
To: <catalin.marinas@....com>, <will@...nel.org>, <oleg@...hat.com>,
	<tglx@...utronix.de>, <peterz@...radead.org>, <luto@...nel.org>,
	<kees@...nel.org>, <wad@...omium.org>, <ruanjinjie@...wei.com>,
	<rostedt@...dmis.org>, <arnd@...db.de>, <ardb@...nel.org>,
	<broonie@...nel.org>, <mark.rutland@....com>, <rick.p.edgecombe@...el.com>,
	<leobras@...hat.com>, <linux-kernel@...r.kernel.org>,
	<linux-arm-kernel@...ts.infradead.org>
Subject: [PATCH v2 3/3] arm64: entry: Convert to generic entry

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.

Signed-off-by: Jinjie Ruan <ruanjinjie@...wei.com>
Tested-by: Jinjie Ruan <ruanjinjie@...wei.com>
Tested-by: Kees Cook <kees@...nel.org>
---
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 |  60 +++++
 arch/arm64/include/asm/syscall.h      |   6 +-
 arch/arm64/include/asm/thread_info.h  |  23 +-
 arch/arm64/kernel/entry-common.c      | 355 ++++++--------------------
 arch/arm64/kernel/ptrace.c            |  72 ++----
 arch/arm64/kernel/signal.c            |   3 +-
 arch/arm64/kernel/syscall.c           |  18 +-
 8 files changed, 182 insertions(+), 356 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..a7eb4fdfc42b
--- /dev/null
+++ b/arch/arm64/include/asm/entry-common.h
@@ -0,0 +1,60 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _ASM_ARM64_ENTRY_COMMON_H
+#define _ASM_ARM64_ENTRY_COMMON_H
+
+#include <linux/sched/signal.h>
+
+#include <asm/daifflags.h>
+#include <asm/fpsimd.h>
+#include <asm/mte.h>
+#include <asm/stacktrace.h>
+
+#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 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 __always_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 __always_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
+
+#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..784ca7ec47d6 100644
--- a/arch/arm64/kernel/entry-common.c
+++ b/arch/arm64/kernel/entry-common.c
@@ -14,6 +14,7 @@
 #include <linux/sched.h>
 #include <linux/sched/debug.h>
 #include <linux/thread_info.h>
+#include <linux/entry-common.h>
 
 #include <asm/cpufeature.h>
 #include <asm/daifflags.h>
@@ -28,201 +29,15 @@
 #include <asm/sysreg.h>
 #include <asm/system_misc.h>
 
-/*
- * 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)
+static __always_inline void exit_to_user_mode_wrapper(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)
-{
-	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);
 }
 
 /*
@@ -259,27 +74,8 @@ 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)
+bool arch_irqentry_exit_need_resched(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
@@ -287,7 +83,7 @@ static void __sched arm64_preempt_schedule_irq(void)
 	 * DAIF we must have handled an NMI, so skip preemption.
 	 */
 	if (system_uses_irq_prio_masking() && read_sysreg(daif))
-		return;
+		return false;
 
 	/*
 	 * Preempting a task from an IRQ means we leave copies of PSTATE
@@ -297,8 +93,10 @@ static void __sched arm64_preempt_schedule_irq(void)
 	 * Only allow a task to be preempted once cpufeatures have been
 	 * enabled.
 	 */
-	if (system_capabilities_finalized())
-		preempt_schedule_irq();
+	if (!system_capabilities_finalized())
+		return false;
+
+	return true;
 }
 
 static void do_interrupt_handler(struct pt_regs *regs,
@@ -320,7 +118,7 @@ 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 +224,43 @@ 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 +275,12 @@ 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 +323,22 @@ 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 +364,22 @@ 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 +394,50 @@ 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 +447,50 @@ 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 +498,28 @@ 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 +584,7 @@ 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 +595,7 @@ 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 +621,15 @@ 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 +640,19 @@ 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 +726,7 @@ 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 +735,7 @@ 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 +760,9 @@ __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..449c11af25ec 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -29,6 +29,7 @@
 #include <linux/regset.h>
 #include <linux/elf.h>
 #include <linux/rseq.h>
+#include <linux/entry-common.h>
 
 #include <asm/compat.h>
 #include <asm/cpufeature.h>
@@ -41,9 +42,6 @@
 #include <asm/traps.h>
 #include <asm/system_misc.h>
 
-#define CREATE_TRACE_POINTS
-#include <trace/events/syscalls.h>
-
 struct pt_regs_offset {
 	const char *name;
 	int offset;
@@ -2184,10 +2182,10 @@ enum ptrace_syscall_dir {
 	PTRACE_SYSCALL_EXIT,
 };
 
-static void report_syscall_enter(struct pt_regs *regs)
+unsigned long arch_prepare_report_syscall_entry(struct pt_regs *regs)
 {
-	int regno;
 	unsigned long saved_reg;
+	int regno;
 
 	/*
 	 * We have some ABI weirdness here in the way that we handle syscall
@@ -2209,72 +2207,50 @@ static void report_syscall_enter(struct pt_regs *regs)
 	saved_reg = regs->regs[regno];
 	regs->regs[regno] = PTRACE_SYSCALL_ENTER;
 
-	if (ptrace_report_syscall_entry(regs))
-		forget_syscall(regs);
+	return saved_reg;
+}
+
+void arch_post_report_syscall_entry(struct pt_regs *regs, unsigned long saved_reg)
+{
+	int regno = (is_compat_task() ? 12 : 7);
+
 	regs->regs[regno] = saved_reg;
 }
 
-static void report_syscall_exit(struct pt_regs *regs)
+unsigned long arch_prepare_report_syscall_exit(struct pt_regs *regs, unsigned long work)
 {
-	int regno;
 	unsigned long saved_reg;
+	int regno;
 
-	/* See comment for report_syscall_enter() */
+	/* 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 (!test_thread_flag(TIF_SINGLESTEP)) {
-		ptrace_report_syscall_exit(regs, 0);
-		regs->regs[regno] = saved_reg;
-	} else {
-		regs->regs[regno] = saved_reg;
-
+	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.
 		 */
-		ptrace_report_syscall_exit(regs, 1);
+		regs->regs[regno] = saved_reg;
 	}
+
+	return saved_reg;
 }
 
-int syscall_trace_enter(struct pt_regs *regs)
+void arch_post_report_syscall_exit(struct pt_regs *regs, unsigned long saved_reg,
+				   unsigned long work)
 {
-	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);
+	int regno = (is_compat_task() ? 12 : 7);
 
-	audit_syscall_entry(regs->syscallno, regs->orig_x0, regs->regs[1],
-			    regs->regs[2], regs->regs[3]);
-
-	return regs->syscallno;
+	if (!report_single_step(work))
+		regs->regs[regno] = saved_reg;
 }
 
-void syscall_trace_exit(struct pt_regs *regs)
+void arch_forget_syscall(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);
+	forget_syscall(regs);
 }
 
 /*
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 <linux/ratelimit.h>
 #include <linux/rseq.h>
 #include <linux/syscalls.h>
+#include <linux/entry-common.h>
 
 #include <asm/daifflags.h>
 #include <asm/debug-monitors.h>
@@ -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 <linux/ptrace.h>
 #include <linux/randomize_kstack.h>
 #include <linux/syscalls.h>
+#include <linux/entry-common.h>
 
 #include <asm/debug-monitors.h>
 #include <asm/exception.h>
@@ -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)
-- 
2.34.1

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