On 10/19, Oleg Nesterov wrote: > > On 10/19, Oleg Nesterov wrote: > > > > On 10/18, Oleg Nesterov wrote: > > > > > > > The semantics is that the entry report always does like > > > > UTRACE_SYSCALL_ABORT to skip the actual call, and then > > > > there is no exit report. > > > > > > Thanks! this is easy. > > > > Hmm. This is not what I see in upstream kernel... > > > > Afaics, PTRACE_SYSEMU means: > > > > - cancel this syscall, and do _not_ report SYSCALL_ENTRY > > to the tracer > > Argh, I missreaf the next check after test_thread_flag(TIF_SYSCALL_EMU) > in syscall_trace_enter(), we should report SYSCALL_ENTRY and stop... > > > - SYSCALL_EXIT should be reported,
OMG, now I misread ptrace_resume(). SYSEMU doesn't set TIF_SYSCALL_TRACE, so SYSCALL_EXIT should not be reported. Sorry for noise... So. Looks like the only complication is that we should avoid the unnecessary send_sigtrap() in syscall_trace_leave(), but we shouldn't use TIF_SYSCALL_EMU - it must die. Correct? Oleg.
