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References: <20240416123545.7098-4-wsa+renesas@sang-engineering.com> <20240416123545.7098-5-wsa+renesas@sang-engineering.com>
In-Reply-To: <20240416123545.7098-5-wsa+renesas@sang-engineering.com>
From: Geert Uytterhoeven <geert@linux-m68k.org>
Date: Wed, 24 Apr 2024 11:41:03 +0200
Message-ID: <CAMuHMdUiS57QZSEaFZjqFm1EV6Lhfq5XbOiuxxGwbi_VNupjQw@mail.gmail.com>
Subject: Re: [RFC PATCH 1/2] serial: sh-sci: start hrtimer after setting up DMA
To: Wolfram Sang <wsa+renesas@sang-engineering.com>
Cc: linux-renesas-soc@vger.kernel.org, Dirk Behme <dirk.behme@de.bosch.com>, 
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Jiri Slaby <jirislaby@kernel.org>, 
	linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org
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Hi Wolfram,

Thanks for your patch!

On Tue, Apr 16, 2024 at 2:35=E2=80=AFPM Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
> In the RX DMA completion handler, the hrtimer was restarted before DMA
> was set up. If DMA failed, for some reason, it would clean up and the
> hrtimer would run into a NULL-pointer. Restart the timer after DMA was

.. into a NULL-pointer dereference of s->chan_rx.

> successfully set up.
>
> Reported-by: Dirk Behme <dirk.behme@de.bosch.com>
> Closes: https://lore.kernel.org/r/ee6c9e16-9f29-450e-81da-4a8dceaa8fc7@de=
bosch.com
> Fixes: 67f462b069e9 ("serial: sh-sci: Get rid of the workqueue to handle =
receive DMA requests")
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

This is definitely a step in the right direction, so
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

--=20
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k=
org

In personal conversations with technical people, I call myself a hacker. Bu=
t
when I'm talking to journalists I just say "programmer" or something like t=
hat.
                                -- Linus Torvalds