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Date:   Sun, 7 Aug 2022 23:32:01 -0400
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Subject: Re: [PATCH v5 31/32] tracing: Convert to printbuf
To:     Steven Rostedt <rostedt@goodmis.org>,
        "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc:     linux-kernel@vger.kernel.org, pmladek@suse.com,
        Ingo Molnar <mingo@redhat.com>
References: <20220808024128.3219082-1-willy@infradead.org>
 <20220808024128.3219082-32-willy@infradead.org>
 <20220807225113.6a74b481@gandalf.local.home>
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From:   Kent Overstreet <kent.overstreet@gmail.com>
In-Reply-To: <20220807225113.6a74b481@gandalf.local.home>
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On 8/7/22 22:51, Steven Rostedt wrote:
> On Mon,  8 Aug 2022 03:41:27 +0100
> "Matthew Wilcox (Oracle)" <willy@infradead.org> wrote:
> 
>>   
>> @@ -9826,20 +9821,8 @@ static struct notifier_block trace_die_notifier = {
>>   void
>>   trace_printk_seq(struct trace_seq *s)
>>   {
>> -	/* Probably should print a warning here. */
>> -	if (s->seq.len >= TRACE_MAX_PRINT)
>> -		s->seq.len = TRACE_MAX_PRINT;
>> -
>> -	/*
>> -	 * More paranoid code. Although the buffer size is set to
>> -	 * PAGE_SIZE, and TRACE_MAX_PRINT is 1000, this is just
>> -	 * an extra layer of protection.
>> -	 */
>> -	if (WARN_ON_ONCE(s->seq.len >= s->seq.size))
>> -		s->seq.len = s->seq.size - 1;
>> -
>>   	/* should be zero ended, but we are paranoid. */
>> -	s->buffer[s->seq.len] = 0;
>> +	printbuf_nul_terminate(&s->seq);
>>   
>>   	printk(KERN_TRACE "%s", s->buffer);
>>   
>> diff --g
> 
> Please remove the two tracing patches and the deletion of the seq_buf from
> the series.

Well, that's not really an option, as Christoph already (rightly) 
pointed out.

If you've got actual engineering concerns that you'd care to articulate 
I'd (still) like to try to work with you - otherwise, I don't think this 
is something I can accommodate you on.