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Subject: Re: [PATCH 1/2] tty: serial: qcom_geni_serial: No need to stop tx/rx
 on UART shutdown
To:     Douglas Anderson <dianders@chromium.org>,
        gregkh@linuxfoundation.org
Cc:     mka@chromium.org, swboyd@chromium.org, ryandcase@chromium.org,
        bjorn.andersson@linaro.org, skakit@codeaurora.org,
        rojay@codeaurora.org, mgautam@codeaurora.org,
        Andy Gross <agross@kernel.org>,
        Doug Anderson <dianders@google.com>,
        Girish Mahadevan <girishm@codeaurora.org>,
        Jiri Slaby <jslaby@suse.com>,
        Karthikeyan Ramasubramanian <kramasub@codeaurora.org>,
        Sagar Dharia <sdharia@codeaurora.org>,
        linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-serial@vger.kernel.org
References: <20200313134635.1.Icf54c533065306b02b880c46dfd401d8db34e213@changeid>
From:   Akash Asthana <akashast@codeaurora.org>
Message-ID: <ce79643c-e854-a48f-2faf-f405c310a8a7@codeaurora.org>
Date:   Tue, 17 Mar 2020 18:35:31 +0530
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On 3/14/2020 2:16 AM, Douglas Anderson wrote:
> On a board using qcom_geni_serial I found that I could no longer
> interact with kdb if I got a crash after the "agetty" running on the
> same serial port was killed.  This meant that various classes of
> crashes that happened at reboot time were undebuggable.
>
> Reading through the code, I couldn't figure out why qcom_geni_serial
> felt the need to run so much code at port shutdown time.  All we need
> to do is disable the interrupt.
>
> After I make this change then a hardcoded kgdb_breakpoint in some late
> shutdown code now allows me to interact with the debugger.  I also
> could freely close / re-open the port without problems.
>
> Fixes: c4f528795d1a ("tty: serial: msm_geni_serial: Add serial driver support for GENI based QUP")
> Signed-off-by: Douglas Anderson <dianders@chromium.org>
> ---

Looks good to me.

Reviewed-by: Akash Asthana <akashast@codeaurora.org>

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