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Date:   Mon, 31 Jan 2022 22:37:11 +0530
From:   Pratyush Yadav <p.yadav@ti.com>
To:     Mark Brown <broonie@kernel.org>
CC:     Tudor Ambarus <tudor.ambarus@microchip.com>,
        Michael Walle <michael@walle.cc>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Takahiro Kuwano <tkuw584924@gmail.com>,
        <linux-spi@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] spi: spi-mem: check if data buffers are on stack
Message-ID: <20220131170711.ydydtx3jeu3fl7pu@ti.com>
References: <20220131114508.1028306-1-p.yadav@ti.com>
 <YffqNEzjIkApR1HS@sirena.org.uk>
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On 31/01/22 01:55PM, Mark Brown wrote:
> On Mon, Jan 31, 2022 at 05:15:08PM +0530, Pratyush Yadav wrote:
> > The buffers passed in the data phase must be DMA-able. Programmers often
> > don't realise this requirement and pass in buffers that reside on the
> > stack. This can be hard to spot when reviewing code. Reject ops if their
> > data buffer is on the stack to avoid this.
> 
> Acked-by: Mark Brown <broonie@kernel.org>

Thanks. But seems like this is breaking build on arm-socfpga_defconfig. 
Let me take a look into it.

> 
> > +	/* Buffers must be DMA-able. */
> > +	if (op->data.dir == SPI_MEM_DATA_IN &&
> > +	    object_is_on_stack(op->data.buf.in))
> 
> Might be worth a WARN_ON_ONCE() for debuggability?

Okay, I'll add it.

-- 
Regards,
Pratyush Yadav
Texas Instruments Inc.