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Message-ID: <cd41a204107900c890b0234847fa0b62701f74cc.camel@suse.de>
Subject: Re: [PATCH] spi: Skip zero-length transfers in
 spi_transfer_one_message()
From:   Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
To:     Mark Brown <broonie@kernel.org>
Cc:     Robin Murphy <robin.murphy@arm.com>,
        Phil Elwell <phil@raspberrypi.com>, linux-spi@vger.kernel.org,
        linux-kernel@vger.kernel.org
Date:   Fri, 12 Feb 2021 13:48:21 +0100
In-Reply-To: <20210212123118.GB6057@sirena.org.uk>
References: <20210211180820.25757-1-nsaenzjulienne@suse.de>
         <20210212123118.GB6057@sirena.org.uk>
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On Fri, 2021-02-12 at 12:31 +0000, Mark Brown wrote:
> On Thu, Feb 11, 2021 at 07:08:20PM +0100, Nicolas Saenz Julienne wrote:
>=20
> > -		if (xfer->tx_buf || xfer->rx_buf) {
> > +		if ((xfer->tx_buf || xfer->rx_buf) && xfer->len) {
>=20
> I think the issue here is more that some users were passing in buffers
> with zero length transfers, the above check was already intended to
> catch this case but was working on the assumption that if there was
> nothing to transfer then no buffer would be provided.

Fair enough, maybe it makes sense to move the check into __spi_validate() a=
nd
propagate an error upwards?

Regads,
Nicolas


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