Received-SPF: pass (google.com: domain of linux-crypto-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20230310223027.315954-1-krzysztof.kozlowski@linaro.org>
 <20230310223027.315954-2-krzysztof.kozlowski@linaro.org> <ZBPYpYfd29YwN1Dy@gondor.apana.org.au>
 <b8cd828b-edc5-6748-bf97-af0fc85e14a4@linaro.org> <ZBQlKMTcTm1yjete@gondor.apana.org.au>
 <e7cd7252-9cc6-0970-b0e2-35fccde45e86@linaro.org> <ZBQvx0PDQJ4qpnNO@gondor.apana.org.au>
In-Reply-To: <ZBQvx0PDQJ4qpnNO@gondor.apana.org.au>
From:   Ard Biesheuvel <ardb@kernel.org>
Date:   Thu, 23 Mar 2023 09:43:58 +0100
Message-ID: <CAMj1kXH3oZhO=dMBmLzNO_nScJBjcjwUqy2sZbCJwmMS1XtLKg@mail.gmail.com>
Subject: Re: [PATCH 2/2] crypto - img-hash: Drop of_match_ptr for ID table
To:     Herbert Xu <herbert@gondor.apana.org.au>
Cc:     Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        "David S. Miller" <davem@davemloft.net>,
        Nicolas Ferre <nicolas.ferre@microchip.com>,
        Alexandre Belloni <alexandre.belloni@bootlin.com>,
        Claudiu Beznea <claudiu.beznea@microchip.com>,
        linux-crypto@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Fri, 17 Mar 2023 at 10:16, Herbert Xu <herbert@gondor.apana.org.au> wrote:
>
> On Fri, Mar 17, 2023 at 10:01:44AM +0100, Krzysztof Kozlowski wrote:
> >
> > That's not true. There is no waste because having it on x86 allows to
> > match via ACPI PRP0001. It's on purpose there.
>
> Alright how about this, I don't have any OF devices on my machine
> yet this structure is still taking up the extra memory for every
> single device driver.  This is wrong.
>
> > There are OF-drivers used on ACPI and x86/arm64.
>
> Well then they should be selecting OF and everyone will be happy.
>

No. PRP0001 support in ACPI does not depend on OF, so drivers that may
be bound to such devices should not either.

If you are concerned about the memory used by such tables, you can
always propose making PRP0001 support configurable in the ACPI core,
but making individual devices depend on OF for PRP0001 matching seems
wrong to me.