Re: [PATCH 2/3] printk: Add %ptc to safely print a task's comm

From: John Stultz
Date: Wed May 11 2011 - 17:04:54 EST


On Wed, 2011-05-11 at 10:36 -0700, Andi Kleen wrote:
> John Stultz <john.stultz@xxxxxxxxxx> writes:
>
> > Acessing task->comm requires proper locking. However in the past
> > access to current->comm could be done without locking. This
> > is no longer the case, so all comm access needs to be done
> > while holding the comm_lock.
> >
> > In my attempt to clean up unprotected comm access, I've noticed
> > most comm access is done for printk output. To simpify correct
> > locking in these cases, I've introduced a new %ptc format,
> > which will safely print the corresponding task's comm.
> >
> > Example use:
> > printk("%ptc: unaligned epc - sending SIGBUS.\n", current);
>
> Neat. But you probably want a checkpatch rule for this too
> to catch new offenders.

Yea. That's on my queue.

thanks
-john


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