From: "Martin K. Petersen" <martin.petersen@oracle.com>
Subject: Re: [PATCH] Performance Improvement in CRC16 Calculations.
Date: Sat, 25 Aug 2018 22:35:23 -0400
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Cc: "Martin K. Petersen" <martin.petersen@oracle.com>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Jeffrey Lien <Jeff.Lien@wdc.com>,
        Christoph Hellwig <hch@infradead.org>,
        "linux-kernel\@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-crypto\@vger.kernel.org" <linux-crypto@vger.kernel.org>,
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        "linux-scsi\@vger.kernel.org" <linux-scsi@vger.kernel.org>,
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        David Darrington <david.darrington@wdc.com>,
        Jeff Furlong <jeff.furlong@wdc.com>
To: Herbert Xu <herbert@gondor.apana.org.au>
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In-Reply-To: <20180825061205.ygrjjazkooqghrqy@gondor.apana.org.au> (Herbert
        Xu's message of "Sat, 25 Aug 2018 14:12:05 +0800")
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Herbert,

> I don't think this is safe unless you do some kind of locking
> which would slow down the data path.  The easiest fix would be
> to keep the old tfm around forever, or use RCU if RCU read locking
> is acceptable to your use-case.

You're right. There's a small race there.

Patch series coming...

-- 
Martin K. Petersen	Oracle Linux Engineering