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Message-ID: <d7da8ef1-dde3-c7f6-3b78-460d5f8708d3@cornelisnetworks.com>
Date:   Wed, 5 Jul 2023 10:08:16 -0400
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Subject: Re: [PATCH] IB/hfi1: Fix potential deadlock on &sde->flushlist_lock
Content-Language: en-US
To:     Chengfeng Ye <dg573847474@gmail.com>,
        Leon Romanovsky <leon@kernel.org>
Cc:     jgg@ziepe.ca, linux-rdma@vger.kernel.org,
        linux-kernel@vger.kernel.org
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From:   Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
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On 7/5/23 2:47 AM, Chengfeng Ye wrote:
>> Exactly, we already called to spin_lock_irqsave(), there is no value in
>> doing it twice.
> 
> Oh yeah, I just notice that the lock acquisition of &sde->flushlist_lock
> is always nested inside &sde->tail_lock due to the goto. Then it is true
> that no need for irq invariant lock/unlock on &sde->flushlist_lock.
> 
> Thanks much for your reply and your time.

Agree. Thanks Leon for looking at this. I was out of the office and just now
seen it.

-Denny