On Thu, Oct 19, 2017 at 5:18 PM, Oleg Nesterov <[email protected]> wrote: > On 10/19, Andrei Vagin wrote: >> >> Hi Gargi, >> >> This patch breaks CRIU, because it changes a meaning of ns_last_pid. > > ... > >> > @@ -311,7 +297,7 @@ static int pid_ns_ctl_handler(struct ctl_table *table, >> > int write, >> > * it should synchronize its usage with external means. >> > */ >> > >> > - tmp.data = &pid_ns->last_pid; >> > + tmp.data = &pid_ns->idr.idr_next; > > Ah, yes, off-by-one error... > > Gargi, I don't think you need to make another version, I'd suggest you to send > the trivial fix to Andrew, afaics you just need to replace these 2 lines with > > unsigned int last; > int err; > > tmp.data = &last; > err = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); > if (!err) > idr_set_cursor(&pid_ns->idr, last + 1); > return err; I'm not sure entirely understand how this takes care of rolling over of PIDs? Can we ignore that? If yes, won't the tests for CRIU still break?
Thanks, Gargi > > Oleg. >
