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Date: Fri, 8 Jan 2010 09:30:25 +0100
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
To: Roland McGrath <roland@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>, caiqian@redhat.com,
       Heiko Carstens <heiko.carstens@de.ibm.com>,
       Jan Kratochvil <jkratoch@redhat.com>, linux-kernel@vger.kernel.org,
       linux-s390@vger.kernel.org, utrace-devel@redhat.com
Subject: Re: s390 && user_enable_single_step() (Was: odd utrace testing
 results on s390x)
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On Thu,  7 Jan 2010 13:46:42 -0800 (PST)
Roland McGrath <roland@redhat.com> wrote:

> > Clear the TIF_SINGLE_STEP bit in copy_thread. If the new process is
> > not auto-attached by the tracer it is wrong to delivere SIGTRAP to
> > the new process.
> 
> The change is right, but this log entry is confusing.  "auto-attached" has
> nothing to do with it, nor does anything about tracing the new process or
> not.  The new process has not experienced a PER trap of its own, so it is
> wrong to deliver a SIGTRAP that is meant for its creator.

Ok, I changed the wording slightly:

Clear the TIF_SINGLE_STEP bit in copy_thread. The new process did not get
a PER event of its own. It is wrong deliver a SIGTRAP that was meant for
the parent process.

-- 
blue skies,
   Martin.

"Reality continues to ruin my life." - Calvin.