On 2018/09/06 20:07, Dmitry Vyukov wrote: >> Since printk() is slow, printing one line takes nearly 0.01 second. >> As a result, syzbot is stalling for 52 seconds trying to dump 5600 > > I wonder why there are so many of them? > We have at most 8 test processes (each having no more than 16 threads > if that matters). > No more than 1 instance of syz-executor1 at a time. But we see output > like the one below. It has lots of instances of syz-executor1 with > different pid's. So does it print all tasks that ever existed (kernel > does not store that info, right)? Or it livelocks picking up new and > new tasks as they are created slower than they are created? Or we have > tons of zombies? > > ... I don't think they are zombies. Since tasks which already released ->mm are not printed, these tasks are still alive. [ pid ] uid tgid total_vm rss pgtables_bytes swapents oom_score_adj name > [ 8037] 0 8037 17618 8738 131072 0 0 syz-executor1 Maybe something signal / fork() / exit() / wait() related regression?
