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Date:   Mon, 15 Aug 2022 16:29:24 +0530
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Subject: Re: Query regarding deadlock involving cgroup_threadgroup_rwsem and
 cpu_hotplug_lock
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To:     =?UTF-8?Q?Michal_Koutn=c3=bd?= <mkoutny@suse.com>,
        Xuewen Yan <xuewen.yan94@gmail.com>
CC:     Tejun Heo <tj@kernel.org>, Imran Khan <imran.f.khan@oracle.com>,
        <lizefan.x@bytedance.com>, <hannes@cmpxchg.org>,
        <tglx@linutronix.de>, <steven.price@arm.com>,
        <peterz@infradead.org>, <cgroups@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>,
        Zhao Gongyi <zhaogongyi@huawei.com>,
        Zhang Qiao <zhangqiao22@huawei.com>
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From:   Mukesh Ojha <quic_mojha@quicinc.com>
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On 8/15/2022 3:09 PM, Michal Koutný wrote:
> On Mon, Aug 15, 2022 at 05:25:52PM +0800, Xuewen Yan <xuewen.yan94@gmail.com> wrote:
>> Your means is that the problem should be fixed by [1]+[2]'s revert ?
> 
> I understood that was already the combination you had tested.
> You write in [T] that [1] alone causes (another) deadlock and therefore
> the revert of [2] was suggested.
> 
>> I just tested the case which reverted the [2]. Need I test with [1] and [2]?
> 
> It'd be better (unless you haven't already :-), my reasoning is for the
> [1]+[2] combo.

Feel free to add my

Reported-and-tested-by: Mukesh Ojha <quic_mojha@quicinc.com>

-Mukesh
> 
> Thanks,
> Michal
> 
> [T] https://lore.kernel.org/r/CAB8ipk_gCLtvEahsp2DvPJf4NxRsM8WCYmmH=yTd7zQE+81_Yg@mail.gmail.com/