From mboxrd@z Thu Jan  1 00:00:00 1970
From: Imre Deak <imre.deak@intel.com>
Subject: Re: [PATCH] lib/drmtest: don't use asprintf on signal
 paths
Date: Wed, 05 Feb 2014 00:04:46 +0200
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To: Chris Wilson <chris@chris-wilson.co.uk>
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On Tue, 2014-02-04 at 21:29 +0000, Chris Wilson wrote:
> On Tue, Feb 04, 2014 at 09:15:14PM +0200, Imre Deak wrote:
> > It's not signal safe and I got kms_flip in hung state with the backtrace
> > below, while the parent process waiting for the signal helper to exit.
> > It was quite easy to reproduce the bug by running
> > 
> > kms_flip --run-subtest=flip-vs-dpms-off-vs-modeset
> 
> snprintf is not signalsafe either (man 7 signal). X goes as far as
> implementing its own limited pnprintf() instead.

Thanks. I got only as far as to realize that asprintf is not signal-safe
b/c of malloc and didn't remember any place with an official list of
allowed functions..

I also missed at least igt_skip() calling vprintf(), so this needs some
more thought.

--Imre