On 10/24, Sergey Senozhatsky wrote: > > On (10/24/12 20:06), Oleg Nesterov wrote: > > On 10/24, Sergey Senozhatsky wrote: > > > > > > small question, > > > > > > ptrace_notify() and forward calls are able to both indirectly and > > > directly call schedule(), > > > /* direct call from ptrace_stop()*/, > > > should, in this case, rcu_user_enter() be called before > > > tracehook_report_syscall_exit(regs, step) > > > and ptrace chain? > > > > Well, I don't really understand this magic... but why? > > > > My understanding is (I may be wrong)
Oh, I bet I have much more chances to be wrong ;) > that we can schedule() from ptrace chain to I don't understand how ptrace chain differs from, say, audit_syscall_exit(). There is nothing special in ptrace_stop() in this respect. > some arbitrary task, which will continue its execution from the point where > RCU assumes > CPU as not idle, while CPU in fact still in idle state -- no one said > rcu_idle_exit() confused... of course it would be wrong if syscall_trace_leave() is called when CPU is considered idle, > if so, does the same apply to in_user? Not sure we understand each other. But I believe that ->in_user should be already false when syscall_trace_leave() is called. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
