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Date:   Tue, 2 Nov 2021 08:56:14 +0100
From:   Petr Mladek <pmladek@suse.com>
To:     Yafang Shao <laoar.shao@gmail.com>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Kees Cook <keescook@chromium.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
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        Peter Zijlstra <peterz@infradead.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Valentin Schneider <valentin.schneider@arm.com>,
        Qiang Zhang <qiang.zhang@windriver.com>,
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        Dietmar Eggemann <dietmar.eggemann@arm.com>,
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Subject: Re: [PATCH v7 00/11] extend task comm from 16 to 24
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On Tue 2021-11-02 09:26:35, Yafang Shao wrote:
> On Tue, Nov 2, 2021 at 9:18 AM Steven Rostedt <rostedt@goodmis.org> wrote:
> > On Tue, 2 Nov 2021 09:09:50 +0800
> > Yafang Shao <laoar.shao@gmail.com> wrote:
> > >      Now we only care about kthread, so we can put the pointer into a
> > > kthread specific struct.
> > >      For example in the struct kthread, or in kthread->data (which may
> > > conflict with workqueue).
> >
> > No, add a new field to the structure. "full_name" or something like that.
> > I'm guessing it should be NULL if the name fits in TASK_COMM_LEN and
> > allocated if the name had to be truncated.
> >
> > Do not overload data with this. That will just make things confusing.
> > There's not that many kthreads, where an addition of an 8 byte pointer is
> > going to cause issues.
> 
> Sure, I will add a new field named "full_name", which only be
> allocated if the kthread's comm is truncated.

The plan looks good to me.

One more thing. It should obsolete the workqueue-specific solution.
It would be great to clean up the workqueue code as the next step.

Best Regards,
Petr