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Date:   Fri, 9 Jun 2023 17:24:04 +0800
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Cc:     Eric Biggers <ebiggers@kernel.org>,
        "meenakshi.aggarwal@nxp.com" <meenakshi.aggarwal@nxp.com>,
        "horia.geanta@nxp.com" <horia.geanta@nxp.com>,
        "V.sethi@nxp.com" <V.sethi@nxp.com>,
        "pankaj.gupta@nxp.com" <pankaj.gupta@nxp.com>,
        "gaurav.jain@nxp.com" <gaurav.jain@nxp.com>,
        "davem@davemloft.net" <davem@davemloft.net>,
        "linux-crypto@vger.kernel.org" <linux-crypto@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "iuliana.prodan@nxp.com" <iuliana.prodan@nxp.com>,
        lucas.segarra.fernandez@intel.com
Subject: Re: [PATCH 0/5] Remove CRYPTO_ALG_ALLOCATES_MEMORY flag
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On Thu, Jun 01, 2023 at 12:23:58PM +0100, Giovanni Cabiddu wrote:
>
> BTW, some time ago we did an assessment of the users of
> !CRYPTO_ALG_ALLOCATES_MEMORY and we came to the conclusion that we
> cannot just update the documentation.
> dm-crypt uses scatterlists with at most 4 entries. dm-integrity,
> instead, might allocate memory for scatterlists with an arbitrary number
> of entries.

dm-integrity shouldn't be using ALLOCATES_MEMORY at all.  It's
using GFP_KERNEL allocations right next to the crypto operations.

But those are some seriously big crypto operations, 16 thousand
4K pages in one hit?

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt