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Date:   Fri, 6 May 2022 09:09:41 -0600
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Subject: Re: [PATCH] nvme: Ensure ret is always initialized in
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To:     Nathan Chancellor <nathan@kernel.org>, Jens Axboe <axboe@fb.com>,
        Christoph Hellwig <hch@lst.de>,
        Keith Busch <kbusch@kernel.org>,
        Sagi Grimberg <sagi@grimberg.me>
Cc:     Nick Desaulniers <ndesaulniers@google.com>,
        Tom Rix <trix@redhat.com>, Kanchan Joshi <joshi.k@samsung.com>,
        Anuj Gupta <anuj20.g@samsung.com>,
        linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org,
        llvm@lists.linux.dev, kernel test robot <lkp@intel.com>
References: <20220506150357.2443040-1-nathan@kernel.org>
From:   Jens Axboe <axboe@kernel.dk>
In-Reply-To: <20220506150357.2443040-1-nathan@kernel.org>
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On 5/6/22 9:03 AM, Nathan Chancellor wrote:
> Clang warns:
> 
>   drivers/nvme/host/ioctl.c:674:6: error: variable 'ret' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
>           if (ns)
>               ^~
>   drivers/nvme/host/ioctl.c:677:9: note: uninitialized use occurs here
>           return ret;
>                  ^~~
>   drivers/nvme/host/ioctl.c:674:2: note: remove the 'if' if its condition is always true
>           if (ns)
>           ^~~~~~~
>   drivers/nvme/host/ioctl.c:672:9: note: initialize the variable 'ret' to silence this warning
>           int ret;
>                  ^
>                   = 0
>   1 error generated.
> 
> Initialize ret to zero so that it cannot be used uninitialized.

Thanks, will fold this in.

> Or alternatively, remove the 'if (ns)' if ns can never be NULL; I tried
> going down the rabbit hole to see if that is possible but I got a little
> lost :^)

For the admin queue, ns can be NULL.

-- 
Jens Axboe