entry: Add arch_ptrace_report_syscall_entry/exit()

ARM64 requires a architecture specific ptrace wrapper as it needs to save
and restore scratch registers.

Provide arch_ptrace_report_syscall_entry/exit() wrappers which fall back to
ptrace_report_syscall_entry/exit() if the architecture does not provide
them.

No functional change intended.

[ tglx: Massaged changelog and comments ]

Suggested-by: Mark Rutland <mark.rutland@arm.com>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Kevin Brodsky <kevin.brodsky@arm.com>
Link: https://patch.msgid.link/20260128031934.3906955-11-ruanjinjie@huawei.com

diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h
index 5316004940c0b0e11d0bbe43e2e7cbbdb09ae364..bea207e32c58f9882e1b9990b1e6908670c0ce13 100644 (file)
--- a/include/linux/entry-common.h
+++ b/include/linux/entry-common.h
@@ -45,6 +45,24 @@
                                 SYSCALL_WORK_SYSCALL_EXIT_TRAP |       \
                                 ARCH_SYSCALL_WORK_EXIT)
 
+/**
+ * arch_ptrace_report_syscall_entry - Architecture specific ptrace_report_syscall_entry() wrapper
+ *
+ * Invoked from syscall_trace_enter() to wrap ptrace_report_syscall_entry().
+ *
+ * This allows architecture specific ptrace_report_syscall_entry()
+ * implementations. If not defined by the architecture this falls back to
+ * to ptrace_report_syscall_entry().
+ */
+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, unsigned long work);
 
 /**
@@ -112,6 +130,24 @@ 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()
+ *
+ * This allows architecture specific ptrace_report_syscall_exit()
+ * implementations. If not defined by the architecture this falls back to
+ * to ptrace_report_syscall_exit().
+ */
+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 e6237b536d8b7a54ca092fcf301be7701a059fa7..bb5f61f5629d47666b38df980fd26cb22cc8b64b 100644 (file)
--- a/kernel/entry/syscall-common.c
+++ b/kernel/entry/syscall-common.c
@@ -33,7 +33,7 @@ long syscall_trace_enter(struct pt_regs *regs, unsigned long work)
 
        /* 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;
        }
@@ -99,5 +99,5 @@ 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);
 }