Re: 2.6.25.3: su gets stuck for root

[Vegard Nossum]

On Mon, Jun 2, 2008 at 2:28 PM, Alan Cox <alan@xxxxxxxxxx> wrote:
> On Mon, Jun 02, 2008 at 12:57:07PM +0200, Vegard Nossum wrote:
>> I guess this still doesn't explain why TTOU doesn't block (IOW, stop
>> the process, right?) in this case, because my test program does not
>> touch it.
>
> I see the parent process sleeping and the child taking TTOU and going to
> state T. That again is correct.
>
> alan      3219  0.0  0.0   3652   384 pts/5    S    13:11   0:00 ./repro
> alan      3220  0.0  0.0   3652   204 pts/5    T    13:11   0:00 ./repro
>
> If you run it without any straces etc do you see it blocked in T or sitting
> in R ?

Without any straces, it is blocked in T. Like Joe's report.

With strace, it's in R.

Exactly as you said, correct and expected behaviour.

So this is not a kernel problem at all.

I'm sorry for having wasted your time :-(


Vegard

-- 
"The animistic metaphor of the bug that maliciously sneaked in while
the programmer was not looking is intellectually dishonest as it
disguises that the error is the programmer's own creation."
	-- E. W. Dijkstra, EWD1036
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