Extract arch_fill_sigtrap_info() from send_sigtrap() and change
syscall_trace_leave() to rely on tracehook_report_syscall_exit()
to handle stepping.
Note: before this patch x86 generated the unnecessary SIGTRAP
when PTRACE_SINGLESTEP done at the syscall-exit stop, now x86
matches other architectures.
---
arch/x86/include/asm/ptrace.h | 5 ++++
arch/x86/kernel/ptrace.c | 51 +++++++++++++++++++++++-------------------
2 files changed, 33 insertions(+), 23 deletions(-)
--- TH/arch/x86/include/asm/ptrace.h~2_CONVERT_X86 2009-06-11
14:16:46.000000000 +0200
+++ TH/arch/x86/include/asm/ptrace.h 2009-11-08 20:45:21.000000000 +0100
@@ -230,6 +230,11 @@ extern void user_enable_block_step(struc
#define arch_has_block_step() (boot_cpu_data.x86 >= 6)
#endif
+struct siginfo;
+void arch_fill_sigtrap_info(struct task_struct *tsk, struct pt_regs *regs,
+ struct siginfo *info);
+#define arch_has_fill_sigtrap_info
+
struct user_desc;
extern int do_get_thread_area(struct task_struct *p, int idx,
struct user_desc __user *info);
--- TH/arch/x86/kernel/ptrace.c~2_CONVERT_X86 2009-09-23 21:12:01.000000000
+0200
+++ TH/arch/x86/kernel/ptrace.c 2009-11-08 20:54:26.000000000 +0100
@@ -1437,21 +1437,33 @@ const struct user_regset_view *task_user
#endif
}
-void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
- int error_code, int si_code)
+static inline void fill_sigtrap_info(struct task_struct *tsk,
+ struct pt_regs *regs,
+ int error_code, int si_code,
+ struct siginfo *info)
{
- struct siginfo info;
-
tsk->thread.trap_no = 1;
tsk->thread.error_code = error_code;
- memset(&info, 0, sizeof(info));
- info.si_signo = SIGTRAP;
- info.si_code = si_code;
+ memset(info, 0, sizeof(*info));
+ info->si_signo = SIGTRAP;
+ info->si_code = si_code;
+ info->si_addr = user_mode_vm(regs) ? (void __user *) regs->ip : NULL;
+}
- /* User-mode ip? */
- info.si_addr = user_mode_vm(regs) ? (void __user *) regs->ip : NULL;
+void arch_fill_sigtrap_info(struct task_struct *tsk,
+ struct pt_regs *regs,
+ struct siginfo *info)
+{
+ fill_sigtrap_info(tsk, regs, 0, TRAP_BRKPT, info);
+}
+void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
+ int error_code, int si_code)
+{
+ struct siginfo info;
+
+ fill_sigtrap_info(tsk, regs, error_code, si_code, &info);
/* Send us the fake SIGTRAP */
force_sig_info(SIGTRAP, &info, tsk);
}
@@ -1516,29 +1528,22 @@ asmregparm long syscall_trace_enter(stru
asmregparm void syscall_trace_leave(struct pt_regs *regs)
{
+ bool step;
+
if (unlikely(current->audit_context))
audit_syscall_exit(AUDITSC_RESULT(regs->ax), regs->ax);
if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
trace_sys_exit(regs, regs->ax);
- if (test_thread_flag(TIF_SYSCALL_TRACE))
- tracehook_report_syscall_exit(regs, 0);
-
/*
* If TIF_SYSCALL_EMU is set, we only get here because of
* TIF_SINGLESTEP (i.e. this is PTRACE_SYSEMU_SINGLESTEP).
* We already reported this syscall instruction in
- * syscall_trace_enter(), so don't do any more now.
- */
- if (unlikely(test_thread_flag(TIF_SYSCALL_EMU)))
- return;
-
- /*
- * If we are single-stepping, synthesize a trap to follow the
- * system call instruction.
+ * syscall_trace_enter().
*/
- if (test_thread_flag(TIF_SINGLESTEP) &&
- tracehook_consider_fatal_signal(current, SIGTRAP))
- send_sigtrap(current, regs, 0, TRAP_BRKPT);
+ step = unlikely(test_thread_flag(TIF_SINGLESTEP)) &&
+ !test_thread_flag(TIF_SYSCALL_EMU);
+ if (step || test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall_exit(regs, step);
}
