Message-ID: <1cf77005-1825-0d34-6d34-e1b513c28113@linux.ibm.com>
Date:   Wed, 5 Jan 2022 13:03:47 +0100
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Subject: Re: [RFC PATCH net v2 1/2] net/smc: Resolve the race between link
 group access and termination
Content-Language: en-US
To:     Wen Gu <guwen@linux.alibaba.com>, davem@davemloft.net,
        kuba@kernel.org
Cc:     linux-s390@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, dust.li@linux.alibaba.com,
        tonylu@linux.alibaba.com
References: <1640704432-76825-1-git-send-email-guwen@linux.alibaba.com>
 <1640704432-76825-2-git-send-email-guwen@linux.alibaba.com>
 <4ec6e460-96d1-fedc-96ff-79a98fd38de8@linux.ibm.com>
 <0a972bf8-1d7b-a211-2c11-50e86c87700e@linux.alibaba.com>
 <4df6c3c1-7d52-6bfa-9b0d-365de5332c06@linux.ibm.com>
 <095c6e45-dd9e-1809-ae51-224679783241@linux.alibaba.com>
From:   Karsten Graul <kgraul@linux.ibm.com>
Organization: IBM Deutschland Research & Development GmbH
In-Reply-To: <095c6e45-dd9e-1809-ae51-224679783241@linux.alibaba.com>
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On 05/01/2022 09:27, Wen Gu wrote:
> On 2022/1/3 6:36 pm, Karsten Graul wrote:
>> On 31/12/2021 10:44, Wen Gu wrote:
>>> On 2021/12/29 8:56 pm, Karsten Graul wrote:
>>>> On 28/12/2021 16:13, Wen Gu wrote:
>>>>> We encountered some crashes caused by the race between the access
>>>>> and the termination of link groups.
> So I think checking conn->alert_token_local has the same effect with checking conn->lgr to
> identify whether the link group pointed by conn->lgr is still healthy and able to be used.

Yeah that sounds like a good solution for that! So is it now guaranteed that conn->lgr is always
set and this check can really be removed completely, or should there be a new helper that checks
conn->lgr and the alert_token, like smc_lgr_valid() ?