Re: Calling current() from interrupt context

From: Jamie Lokier (
Date: Sun Oct 08 2000 - 17:30:17 EST

Kenn Humborg wrote:
> My feeling is that interrupt code has no business calling current(),
> but I don't know the kernel well enough to be sure. Is there any
> interrupt-level code that calls current() or is it a design
> principle that it cannot be called?

It's a design principle that you must not call "current" in interrupt,
bottom half or tasklet context. From time to time buggy code is found
to do this, and it gets away with it. (See recent thread on network I/O
signal delivery using the wrong credentials due to a bug like this).

So if you can make the machine crash utterly when calling "current" in
irq context, or when dereferencing the result, that would probably be a
good thing :-)

-- Jamie
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