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Date:   Thu, 05 May 2022 17:38:14 +0200
From:   Michael Walle <michael@walle.cc>
To:     Nathan Chancellor <nathan@kernel.org>
Cc:     Codrin Ciubotariu <codrin.ciubotariu@microchip.com>,
        Nicolas Ferre <nicolas.ferre@microchip.com>,
        Alexandre Belloni <alexandre.belloni@bootlin.com>,
        Claudiu Beznea <claudiu.beznea@microchip.com>,
        Wolfram Sang <wsa@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Tom Rix <trix@redhat.com>, linux-i2c@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        llvm@lists.linux.dev
Subject: Re: [PATCH] i2c: at91: Initialize dma_buf in at91_twi_xfer()
In-Reply-To: <20220505152738.1440249-1-nathan@kernel.org>
References: <20220505152738.1440249-1-nathan@kernel.org>
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Am 2022-05-05 17:27, schrieb Nathan Chancellor:
> Clang warns:
> 
>   drivers/i2c/busses/i2c-at91-master.c:707:6: warning: variable
> 'dma_buf' is used uninitialized whenever 'if' condition is false
> [-Wsometimes-uninitialized]
>           if (dev->use_dma) {
>               ^~~~~~~~~~~~
>   drivers/i2c/busses/i2c-at91-master.c:717:27: note: uninitialized use
> occurs here
>           i2c_put_dma_safe_msg_buf(dma_buf, m_start, !ret);
>                                    ^~~~~~~
> 
> Initialize dma_buf to NULL, as i2c_put_dma_safe_msg_buf() is a no-op
> when the first argument is NULL, which will work for the !dev->use_dma
> case.
> 
> Fixes: 03fbb903c8bf ("i2c: at91: use dma safe buffers")
> Link: https://github.com/ClangBuiltLinux/linux/issues/1629
> Signed-off-by: Nathan Chancellor <nathan@kernel.org>

Thanks for fixing.

Reviewed-by: Michael Walle <michael@walle.cc>

-michael