2011/3/26 Michel Lespinasse <walken@xxxxxxxxxx>: > On Fri, Mar 25, 2011 at 01:05:50PM +0900, Minchan Kim wrote: >> Okay. Each approach has a pros and cons and at least, now anyone >> doesn't provide any method and comments but I agree it is needed(ex, >> careless and lazy admin could need it strongly). Let us wait a little >> bit more. Maybe google guys or redhat/suse guys would have a opinion. > > I haven't heard of fork bombs being an issue for us (and it's not been > for me on my desktop, either). > > Also, I want to point out that there is a classical userspace solution > for this, as implemented by killall5 for example. One can do > kill(-1, SIGSTOP) to stop all processes that they can send > signals to (except for init and itself). Target processes > can never catch or ignore the SIGSTOP. This stops the fork bomb > from causing further damage. Then, one can look at the process > tree and do whatever is appropriate - including killing by uid, > by cgroup or whatever policies one wants to implement in userspace. > Finally, the remaining processes can be restarted using SIGCONT. > Can that solution work even under OOM situation without new login/commands ? Please show us your solution, how to avoid Andrey's Bomb with your way. Then, we can add Documentation, at least. Or you can show us your tool. Maybe it is.... - running as a daemon. (because it has to lock its work memory before OOM.) - mlockall its own memory to work under OOM. - It can show process tree of users/admin or do all in automatic way with user's policy. - tell us which process is guilty. - wakes up automatically when OOM happens.....IOW, OOM should have some notifier to userland. - never allocate any memory at running. (maybe it can't use libc.) - never be blocked by any locks, for example, some other task's mmap_sem. One of typical mistakes of admins at OOM is typing 'ps' to see what happens..... - Can be used even with GUI system, which can't show console. Thanks, -Kame -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>