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Date:   Wed, 13 Dec 2023 02:07:40 +0800
MIME-Version: 1.0
Subject: Re: [PATCH for-next v7 0/7] On-Demand Paging on SoftRoCE
To:     "Daisuke Matsuda (Fujitsu)" <matsuda-daisuke@fujitsu.com>,
        Jason Gunthorpe <jgg@nvidia.com>
Cc:     "linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>,
        "leon@kernel.org" <leon@kernel.org>,
        "zyjzyj2000@gmail.com" <zyjzyj2000@gmail.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "rpearsonhpe@gmail.com" <rpearsonhpe@gmail.com>,
        "Xiao Yang (Fujitsu)" <yangx.jy@fujitsu.com>,
        "Zhijian Li (Fujitsu)" <lizhijian@fujitsu.com>,
        "Yasunori Gotou (Fujitsu)" <y-goto@fujitsu.com>
References: <cover.1699503619.git.matsuda-daisuke@fujitsu.com>
 <20231205001139.GA2772824@nvidia.com>
 <d639b4e3-e12a-47e8-9b03-2398b076fdbf@linux.dev>
 <OS3PR01MB98659C7691D5DFB98D98D2BDE58BA@OS3PR01MB9865.jpnprd01.prod.outlook.com>
From:   Zhu Yanjun <yanjun.zhu@linux.dev>
In-Reply-To: <OS3PR01MB98659C7691D5DFB98D98D2BDE58BA@OS3PR01MB9865.jpnprd01.prod.outlook.com>
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在 2023/12/7 14:37, Daisuke Matsuda (Fujitsu) 写道:
> On Tue, Dec 5, 2023 10:51 AM Zhu Yanjun wrote:
>>
>> 在 2023/12/5 8:11, Jason Gunthorpe 写道:
>>> On Thu, Nov 09, 2023 at 02:44:45PM +0900, Daisuke Matsuda wrote:
>>>>
>>>> Daisuke Matsuda (7):
>>>>     RDMA/rxe: Always defer tasks on responder and completer to workqueue
>>>>     RDMA/rxe: Make MR functions accessible from other rxe source code
>>>>     RDMA/rxe: Move resp_states definition to rxe_verbs.h
>>>>     RDMA/rxe: Add page invalidation support
>>>>     RDMA/rxe: Allow registering MRs for On-Demand Paging
>>>>     RDMA/rxe: Add support for Send/Recv/Write/Read with ODP
>>>>     RDMA/rxe: Add support for the traditional Atomic operations with ODP
>>>
>>> What is the current situation with rxe? I don't recall seeing the bugs
>>> that were reported get fixed?
> 
> Well, I suppose Jason is mentioning "blktests srp/002 hang".
> cf. https://lore.kernel.org/linux-rdma/dsg6rd66tyiei32zaxs6ddv5ebefr5vtxjwz6d2ewqrcwisogl@ge7jzan7dg5u/T/
> 
> It is likely to be a timing issue. Bob reported that "siw hangs with the debug kernel",
> so the hang looks not specific to rxe.
> cf. https://lore.kernel.org/all/53ede78a-f73d-44cd-a555-f8ff36bd9c55@acm.org/T/
> I think we need to decide whether to continue to block patches to rxe since nobody has successfully fixed the issue.
> 
> 
> There is another issue that causes kernel panic.
> [bug report][bisected] rdma_rxe: blktests srp lead kernel panic with 64k page size
> cf. https://lore.kernel.org/all/CAHj4cs9XRqE25jyVw9rj9YugffLn5+f=1znaBEnu1usLOciD+g@mail.gmail.com/T/
> 
> https://patchwork.kernel.org/project/linux-rdma/list/?series=798592&state=*
> Zhijian has submitted patches to fix this, and he got some comments.
> It looks he is involved in CXL driver intensively these days.
> I guess he is still working on it.
> 
>>
>> Exactly. A problem is reported in the link
>> https://www.spinics.net/lists/linux-rdma/msg120947.html
>>
>> It seems that a variable 'entry' set but not used
>> [-Wunused-but-set-variable]
> 
> Yeah, I can revise the patch anytime.
> 
>>
>> And ODP is an important feature. Should we suggest to add a test case
>> about this ODP in rdma-core to verify this ODP feature?
> 
> Rxe can share the same tests with mlx5.
> I added test cases for Write, Read and Atomic operations with ODP,
> and we can add more tests if there are any suggestions.
> Cf. https://github.com/linux-rdma/rdma-core/blob/master/tests/test_odp.py

Thanks a lot.
Do you make tests with blktests after your patches are applied with the 
latest kernel?

Zhu Yanjun

> 
> Thanks,
> Daisuke Matsuda
> 
>>
>> Zhu Yanjun
>>
>>>
>>> I'm reluctant to dig a deeper hold until it is done?
>>>
>>> Thanks,
>>> Jason
>