Re: Fix signalfd interaction with thread-private signals

Linus Torvalds
2007-06-21T18:36:22Z

On Thu, 21 Jun 2007, Oleg Nesterov wrote:
>
> Yes, the target thread is the one that caused the SIGSEGV, it sends the signal
> to itself. entry.S:ret_from_exception should notice this signal and _dequeue_
> it, no? This signal could be stealed by signal(SIG_IGN) which runs after it
> was delivered.

Right. But it will dequeue it by *taking* it.

IOW, this has absolutely nothing to do with signalfd.

That's all I mean.

> My point was that it is _possible_ to steal a thread-local SIGSEGV even without
> signalfd, nothing bad should happen.

That makes no sense.

You don't "steal" it. You take it. It's what SIGSEGV (and _any_ signal)
has always been about. You get the signal, enter the signal handler, and
handle it.

No "stealing". No signalfd, no *nothing*. Just normal signal behaviour.

Linus