lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Wed, 5 Dec 2007 17:08:47 -0800 (PST)
From:	Davide Libenzi <>
To:	Oleg Nesterov <>
cc:	Andrew Morton <>,
	Ingo Molnar <>,
	Linus Torvalds <>,
	Roland McGrath <>,
	Linux Kernel Mailing List <>
Subject: Re: [PATCH] fix group stop with exit race

On Wed, 5 Dec 2007, Oleg Nesterov wrote:

> do_signal_stop() counts all sub-thread and sets ->group_stop_count accordingly.
> Every thread should decrement ->group_stop_count and stop, the last one should
> notify the parent.
> However a sub-thread can exit before it notices the signal_pending(), or it may
> be somewhere in do_exit() already. In that case the group stop never finishes
> properly.
> Note: this is a minimal fix, we can add some optimizations later. Say we can
> return quickly if thread_group_empty(). Also, we can move some signal related
> code from exit_notify() to exit_signals().
> Signed-off-by: Oleg Nesterov <>

Looks OK for me, even though we're doing more work on the exit path. OTOH 
I don't see a non-racy way of doing it w/out grabbing the lock. Did you 
try to bench how much this change costs?
Anyway, looks sane to me...

Acked-by: Davide Libenzi <>

- Davide

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

Powered by blists - more mailing lists