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Date:   Tue, 26 Oct 2021 12:26:14 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Tao Zhou <tao.zhou@linux.dev>
Cc:     Daniel Bristot de Oliveira <bristot@kernel.org>,
        Ingo Molnar <mingo@redhat.com>,
        Tom Zanussi <zanussi@kernel.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Juri Lelli <juri.lelli@redhat.com>,
        Clark Williams <williams@redhat.com>,
        John Kacur <jkacur@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        linux-rt-users@vger.kernel.org, linux-trace-devel@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH V5 08/20] rtla: Helper functions for rtla
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On Wed, 27 Oct 2021 00:22:04 +0800
Tao Zhou <tao.zhou@linux.dev> wrote:

> > +	do {
> > +		retval = read(in_fd, buffer, sizeof(buffer));
> > +		if (read <= 0)  
> 
> check "retval" not read. Like:
> 
>   if (retval <= 0)

OUCH! Good check.

Daniel, did that not produce any warnings??

-- Steve


> 
> > +			goto out_close;
> > +
> > +		retval = write(out_fd, buffer, retval);
> > +		if (retval < 0)
> > +			goto out_close;
> > +	} while (retval > 0);