Differ from generic entry, due to historical reasons, ARM64 need to save/restore during syscall entry/exit because ARM64 use a scratch register (ip(r12) on AArch32, x7 on AArch64) to denote syscall entry/exit.
In preparation for moving arm64 over to the generic entry code, add arch_ptrace_report_syscall_entry/exit() as the default ptrace_report_syscall_entry/exit() implementation. This allows arm64 to implement the architecture specific version. This allows arm64 to implement the architecture specific version. Reviewed-by: Kevin Brodsky <[email protected]> Suggested-by: Mark Rutland <[email protected]> Suggested-by: Thomas Gleixner <[email protected]> Signed-off-by: Jinjie Ruan <[email protected]> --- include/linux/entry-common.h | 39 +++++++++++++++++++++++++++++++++++ kernel/entry/syscall-common.c | 4 ++-- 2 files changed, 41 insertions(+), 2 deletions(-) diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h index 0de0e60630e1..17171e8873fc 100644 --- a/include/linux/entry-common.h +++ b/include/linux/entry-common.h @@ -45,6 +45,25 @@ SYSCALL_WORK_SYSCALL_EXIT_TRAP | \ ARCH_SYSCALL_WORK_EXIT) +/** + * arch_ptrace_report_syscall_entry - Architecture specific + * ptrace_report_syscall_entry(). + * + * Invoked from syscall_trace_enter() to wrap ptrace_report_syscall_entry(). + * Defaults to ptrace_report_syscall_entry. + * + * The main purpose is to support arch-specific ptrace_report_syscall_entry() + * implementation. + */ +static __always_inline int arch_ptrace_report_syscall_entry(struct pt_regs *regs); + +#ifndef arch_ptrace_report_syscall_entry +static __always_inline int arch_ptrace_report_syscall_entry(struct pt_regs *regs) +{ + return ptrace_report_syscall_entry(regs); +} +#endif + long syscall_trace_enter(struct pt_regs *regs, long syscall, unsigned long work); /** @@ -112,6 +131,26 @@ static __always_inline long syscall_enter_from_user_mode(struct pt_regs *regs, l return ret; } +/** + * arch_ptrace_report_syscall_exit - Architecture specific + * ptrace_report_syscall_exit. + * + * Invoked from syscall_exit_work() to wrap ptrace_report_syscall_exit(). + * + * The main purpose is to support arch-specific ptrace_report_syscall_exit + * implementation. + */ +static __always_inline void arch_ptrace_report_syscall_exit(struct pt_regs *regs, + int step); + +#ifndef arch_ptrace_report_syscall_exit +static __always_inline void arch_ptrace_report_syscall_exit(struct pt_regs *regs, + int step) +{ + ptrace_report_syscall_exit(regs, step); +} +#endif + /** * syscall_exit_work - Handle work before returning to user mode * @regs: Pointer to current pt_regs diff --git a/kernel/entry/syscall-common.c b/kernel/entry/syscall-common.c index 940a597ded40..fe38f84dfff3 100644 --- a/kernel/entry/syscall-common.c +++ b/kernel/entry/syscall-common.c @@ -34,7 +34,7 @@ long syscall_trace_enter(struct pt_regs *regs, long syscall, /* Handle ptrace */ if (work & (SYSCALL_WORK_SYSCALL_TRACE | SYSCALL_WORK_SYSCALL_EMU)) { - ret = ptrace_report_syscall_entry(regs); + ret = arch_ptrace_report_syscall_entry(regs); if (ret || (work & SYSCALL_WORK_SYSCALL_EMU)) return -1L; } @@ -100,5 +100,5 @@ void syscall_exit_work(struct pt_regs *regs, unsigned long work) step = report_single_step(work); if (step || work & SYSCALL_WORK_SYSCALL_TRACE) - ptrace_report_syscall_exit(regs, step); + arch_ptrace_report_syscall_exit(regs, step); } -- 2.34.1
