On 08/31, Christian Brauner wrote: > > --- a/kernel/exit.c > +++ b/kernel/exit.c > @@ -934,6 +934,7 @@ struct wait_opts { > > wait_queue_entry_t child_wait; > int notask_error; > + int eagain_error; > }; > > static int eligible_pid(struct wait_opts *wo, struct task_struct *p) > @@ -1461,6 +1462,8 @@ static long do_wait(struct wait_opts *wo) > > notask: > retval = wo->notask_error; > + if (!retval) > + retval = wo->eagain_error; > if (!retval && !(wo->wo_flags & WNOHANG)) { > retval = -ERESTARTSYS; I must have missed something but I don't understand why do we need the new ->eagain_error and the change in do_wait(). > @@ -1544,6 +1551,11 @@ static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop, > wo.wo_flags = options; > wo.wo_info = infop; > wo.wo_rusage = ru; > + wo.eagain_error = 0; > + if (f_flags & O_NONBLOCK) { > + wo.wo_flags |= WNOHANG; > + wo.eagain_error = -EAGAIN; > + } > ret = do_wait(&wo); Can't kernel_waitid() simply do if (f_flags & O_NONBLOCK) wo.wo_flags |= WNOHANG; ret = do_wait(); if (!ret & (f_flags & O_NONBLOCK)) ret = -EAGAIN; ? Oleg.