Commit d5196503 authored by Oleg Nesterov's avatar Oleg Nesterov Committed by Linus Torvalds

ptrace: x86: change syscall_trace_leave() to rely on tracehook when stepping

Suggested by Roland.

Unlike powepc, x86 always calls tracehook_report_syscall_exit(step) with
step = 0, and sends the trap by hand.

This results in unnecessary SIGTRAP when PTRACE_SINGLESTEP follows the
syscall-exit stop.

Change syscall_trace_leave() to pass the correct "step" argument to
tracehook and remove the send_sigtrap() logic.
Signed-off-by: default avatarOleg Nesterov <oleg@redhat.com>
Acked-by: default avatarRoland McGrath <roland@redhat.com>
Cc: <linux-arch@vger.kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 7f38551f
......@@ -1767,29 +1767,22 @@ asmregparm long syscall_trace_enter(struct pt_regs *regs)
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);
}
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