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 <20200630082922.28672-1-cengiz@kernel.wtf>
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From:   Doug Anderson <dianders@chromium.org>
Date:   Tue, 30 Jun 2020 15:32:11 -0700
Message-ID: <CAD=FV=XbMfwAQ+M7oMksd0dv9xjkQrGhU8hVNahn7+vxTuhT6A@mail.gmail.com>
Subject: Re: [PATCH v3] kdb: remove unnecessary null check of dbg_io_ops
To:     Cengiz Can <cengiz@kernel.wtf>
Cc:     Sumit Garg <sumit.garg@linaro.org>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Daniel Thompson <daniel.thompson@linaro.org>,
        Jason Wessel <jason.wessel@windriver.com>,
        kgdb-bugreport@lists.sourceforge.net,
        LKML <linux-kernel@vger.kernel.org>,
        Petr Mladek <pmladek@suse.com>
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Hi,

On Tue, Jun 30, 2020 at 1:30 AM Cengiz Can <cengiz@kernel.wtf> wrote:
>
> `kdb_msg_write` operates on a global `struct kgdb_io *` called
> `dbg_io_ops`.
>
> It's initialized in `debug_core.c` and checked throughout the debug
> flow.
>
> There's a null check in `kdb_msg_write` which triggers static analyzers
> and gives the (almost entirely wrong) impression that it can be null.
>
> Coverity scanner caught this as CID 1465042.
>
> I have removed the unnecessary null check and eliminated false-positive
> forward null dereference warning.
>
> Signed-off-by: Cengiz Can <cengiz@kernel.wtf>
> ---
>  kernel/debug/kdb/kdb_io.c | 14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)

Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Douglas Anderson <dianders@chromium.org>