Re: [PATCH v2] serial: sh-sci: disable DMA for uart_console

George G. Davis
2019-05-14T15:30:22Z

Hello Geert,

On Tue, May 14, 2019 at 10:28:34AM +0200, Geert Uytterhoeven wrote:
> Hi George,
>
> On Mon, May 13, 2019 at 5:48 PM George G. Davis <george_davis@mentor.com> wrote:
> > As noted in commit 84b40e3b57ee ("serial: 8250: omap: Disable DMA for
> > console UART"), UART console lines use low-level PIO only access functions
> > which will conflict with use of the line when DMA is enabled, e.g. when
> > the console line is also used for systemd messages. So disable DMA
> > support for UART console lines.
> >
> > Fixes: https://patchwork.kernel.org/patch/10929511/
>
> I don't think this is an appropriate reference, as it points to a patch that
> was never applied.

I included it as a link to an upstream problem report similar to other commits
that I previewed. The link provides the extra context that I was perhaps to
lazy to note in the commit header.

> As the problem has basically existed forever,

Agreed

> IMHO no Fixes tag
> is needed.

I've dropped the Fixes line.

> > Reported-by: Michael Rodin <mrodin@de.adit-jv.com>
> > Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com>
> > Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
> > Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> > Cc: stable@vger.kernel.org
> > Signed-off-by: George G. Davis <george_davis@mentor.com>
> > ---
> > v2: Clarify comment regarding DMA support on kernel console,
> > add {Tested,Reviewed}-by:, and Cc: linux-stable lines.
>
> Thanks for the update!

Thanks!

I'll submit v3 later today.

> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
>
> Gr{oetje,eeting}s,
>
> Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
> -- Linus Torvalds

--
Regards,
George