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Subject: Re: NFS over RDMA issues on Linux 5.4
To:     Chuck Lever <chuck.lever@oracle.com>
Cc:     Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        linux-rdma <linux-rdma@vger.kernel.org>
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From:   Timo Rothenpieler <timo@rothenpieler.org>
Message-ID: <371c526c-eaf5-e708-8e7f-0b2c21ae2300@rothenpieler.org>
Date:   Tue, 4 Aug 2020 15:19:54 +0200
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On 04.08.2020 15:12, Chuck Lever wrote:
> 
> 
>> On Aug 4, 2020, at 9:08 AM, Timo Rothenpieler <timo@rothenpieler.org> wrote:
>>
>> On 04.08.2020 14:49, Chuck Lever wrote:
>>> Timo, I tend to think this is not a configuration issue.
>>> Do you know of a known working kernel?
>>
>> This is a brand new system, it's never been running with any kernel older than 5.4, and downgrading it to 4.19 or something else while in operation is unfortunately not easily possible. For a client it would definitely not be out of the question, but the main nfs server I cannot easily downgrade.
>>
>> Also keep in mind that the dmesg spam happens on both server and client simultaneously.
> 
> Let's start with the client only, since restarting it seems to clear the problem.
> 
> 
>> I'll see if I can borrow two of the nodes to turn into a temporary test system for this.
>>
>> The Kernel for this system is self-built and not any distribution kernel.
> 
> Would it be easy to try a kernel earlier in the 5.4.y stable series?

Yes, that should be very straight forward, since I can just use the same 
config.
Got any specific version in mind?