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.

Suggested-by: Mark Rutland <[email protected]>
Suggested-by: Kevin Brodsky <[email protected]>
Suggested-by: Thomas Gleixner <[email protected]>
Signed-off-by: Jinjie Ruan <[email protected]>
---
 kernel/entry/syscall-common.c | 43 +++++++++++++++++++++++++++++++++--
 1 file changed, 41 insertions(+), 2 deletions(-)

diff --git a/kernel/entry/syscall-common.c b/kernel/entry/syscall-common.c
index 66e6ba7fa80c..27310e611567 100644
--- a/kernel/entry/syscall-common.c
+++ b/kernel/entry/syscall-common.c
@@ -17,6 +17,25 @@ static inline void syscall_enter_audit(struct pt_regs *regs, 
long syscall)
        }
 }
 
+/**
+ * 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)
 {
@@ -34,7 +53,7 @@ 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;
        }
@@ -84,6 +103,26 @@ static inline bool report_single_step(unsigned long work)
        return work & SYSCALL_WORK_SYSCALL_EXIT_TRAP;
 }
 
+/**
+ * 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
+
 void syscall_exit_work(struct pt_regs *regs, unsigned long work)
 {
        bool step;
@@ -108,5 +147,5 @@ 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


Reply via email to