Re: Use of alternate stack for signal handler

Kasper Dupont <57203463996516718595@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> Madhav wrote:
>> Can anyone tell me about typical uses of having a different
>> stack for signal handlers? and what may be the disadvantages
>> of using the default stack?
>
> One advantage of using a different stack is, that it will
> still work if the usual stack is full.

I didn't think userland stacks could get "full" without
ulimit(). There's a guard page at bottom that will
automagically map in another page. I don't know if
kernel stacks do this.

> In a multithreaded program, you will have a stack per thread.

Of course, but they will be CoW and buried stack
won't be replicated.

-- Robert

.

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