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Message-ID: <27b90c36-7552-6e6c-4109-3220c90ce83e@huawei.com>
Date:   Fri, 1 Sep 2023 09:34:16 +0800
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Subject: Re: [PATCH] tracing: zero the pipe cpumask on alloc to avoid spurious
 -EBUSY
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To:     Steven Rostedt <rostedt@goodmis.org>
CC:     Brian Foster <bfoster@redhat.com>,
        <linux-trace-kernel@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
References: <20230831125500.986862-1-bfoster@redhat.com>
 <26f8fb43-6ea8-edc2-381d-3600fce261af@huawei.com>
 <20230831163331.6c90c963@rorschach.local.home>
From:   Zheng Yejian <zhengyejian1@huawei.com>
In-Reply-To: <20230831163331.6c90c963@rorschach.local.home>
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On 2023/9/1 04:33, Steven Rostedt wrote:
> On Thu, 31 Aug 2023 21:51:18 +0800
> Zheng Yejian <zhengyejian1@huawei.com> wrote:
> 
>>> Hi,
>>>
>>> I ran into this problem just recently on one of my test VMs immediately
>>> after updating to a v6.5 base. A revert of the aforementioned commit
>>> addressed the problem. I'm not terribly familiar with the tracing code,
>>> but on further inspection I noticed the cpumask doesn't appear to be
>>> initialized anywhere. I suppose this could alternatively do a
>>> cpumask_clear() or whatever after allocation, but either way this
>>> addresses the problem for me.
>>
>> Yes, pipe_cpumask must be initialized.
> 
> Can I add a Reviewed-by tag from you?

Of course :)
Reviewed-by: Zheng Yejian <zhengyejian1@huawei.com>

--

Thanks,
Zheng Yejian

> 
>>
>>>
>>> Please CC on replies as I'm not subscribed to the list. Thanks.
> 
> That's the default with Linux kernel lists.
> 
> -- Steve
>