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Subject: Re: [PATCH] tracing: Fix infinite loop in tracing_read_pipe on
 overflowed print_trace_line
To:     Steven Rostedt <rostedt@goodmis.org>
CC:     <mhiramat@kernel.org>, <linux-kernel@vger.kernel.org>
References: <20221114022946.66255-1-yangjihong1@huawei.com>
 <20221117164003.6e655615@gandalf.local.home>
 <188a48b7-f426-6348-086e-22e56bb07206@huawei.com>
 <20221120144956.30bb1725@rorschach.local.home>
From:   Yang Jihong <yangjihong1@huawei.com>
Message-ID: <894153aa-0dab-dc26-7c31-2bdda7c665b4@huawei.com>
Date:   Thu, 24 Nov 2022 21:04:06 +0800
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Hello,

On 2022/11/21 3:49, Steven Rostedt wrote:
> On Fri, 18 Nov 2022 18:21:12 +0800
> Yang Jihong <yangjihong1@huawei.com> wrote:
> 
>>> That way we can see the broken trace event and not just silently drop it.
>>>    
>> Ok, will change in next version.(Because iter->seq.seq.len may be
>> smaller than strlen(dots), direct subtraction here may not be appropriate.)
> 
> We should only need to do this if the len is maxed out.
> 
> Hmm, len is only updated if it did actually copy it.
> 
> Perhaps we could just add:
> 
> 	trace_seq_puts(&iter->seq, "[LINE TOO BIG]\n");
> 
The v3 patch has been sent according to this solution.

Thanks,
Yang