[PATCH v3 3/3] arm64: entry: Convert to generic entry
Jinjie Ruan
ruanjinjie at huawei.com
Sat Jun 29 01:56:01 PDT 2024
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 <ruanjinjie at huawei.com>
Tested-by: Jinjie Ruan <ruanjinjie at huawei.com>
Tested-by: Kees Cook <kees at kernel.org>
---
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 <linux/thread_info.h>
+
+#include <asm/daifflags.h>
+#include <asm/fpsimd.h>
+#include <asm/mte.h>
+#include <asm/stacktrace.h>
+
+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 <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)
-{
- __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 <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;
@@ -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 <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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