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Date:   Mon, 18 Apr 2022 15:10:34 +0300
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Subject: Re: [EXT] [PATCH v2] crypto: caam - fix i.MX6SX entropy delay value
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To:     Fabio Estevam <festevam@gmail.com>, Varun Sethi <V.Sethi@nxp.com>
Cc:     "herbert@gondor.apana.org.au" <herbert@gondor.apana.org.au>,
        Vabhav Sharma <vabhav.sharma@nxp.com>,
        Gaurav Jain <gaurav.jain@nxp.com>,
        "linux-crypto@vger.kernel.org" <linux-crypto@vger.kernel.org>,
        Fabio Estevam <festevam@denx.de>
References: <20220416135412.4109213-1-festevam@gmail.com>
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On 4/16/2022 10:11 PM, Fabio Estevam wrote:
> Hi Varun,
> 
> On Sat, Apr 16, 2022 at 3:00 PM Varun Sethi <V.Sethi@nxp.com> wrote:
>>
>> Hi Fabio,
>> Vabhav is working on a fix for the Linux driver. He would be introducing a new property in the CAAM device tree node, which would be used for specifying the entropy delay value. This would make the solution generic. This property is optional.
> 
> Unfortunately, a devicetree property solution via optional property
> would not work.
> 
> Such a solution would not be backported to stable kernels and people running old
> devicetree with new kernels would still face the problem.
> 
Indeed.

> This problem is seen since kernel 5.10, so we need a kernel-only fix.
> 
I'd prefer to have this patch (or a kernel-only fix in general)
applied only on the stable kernels, and use the device tree approach
on current kernel.
However, I'm not sure this is acceptable from stable kernels rules' perspective.

The alternative is to merge this patch (btw, please add a Fixes tag)
and then the DT-based solution would also include its removal.

Horia