Re: [PATCH] core dump: remain dumpable

[Oleg Nesterov]

On 10/11, Roland McGrath wrote:
>
> > Hmm. Actually, do we need any check? If another thread (or CLONE_VM task)
> > already started do_coredump(), we must see SIGNAL_GROUP_EXIT when we take
> > ->mmap_sem. In that case coredump_wait() does nothing but returns -EAGAIN.
> 
> You're right again here.  I'm sure the old use predates this checking in
> zap_threads, so it's understandable that something different was needed for
> this synchronization before.

Ugh, sorry, I was wrong. coredump_wait() initializes mm->core_done and sets
mm->core_startup_done before checking SIGNAL_GROUP_EXIT. This means we have
to check ->core_waiters or SIGNAL_GROUP_EXIT before calling coredump_wait().

Oleg.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/