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From: Paul Gortmaker <paul.gortmaker@windriver.com>
Date: Sun, 16 Feb 2014 10:56:24 -0500
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Subject: Re: Anyone using SysRQ key sequences on console serial port ?
To: John Donnelly <john.d@servergy.com>
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On Fri, Feb 14, 2014 at 3:42 PM, John Donnelly <john.d@servergy.com> wrote:
> Hi,
>
>  I tried using the SysRq hotkey sequence on a serial console -
> 3.11.0-5-powerpc-e500mc system, by issuing a " break " and the system
> immediately wedges after displaying "SysRQ : HELP : " using both "Putty" and
> "Teraterm"  terminal emulators. I know the system is dead because my ssh
> sessions stopped too.

Yes it does work -- or at least it _did_ work.  Make sure your dts has an entry

                        compatible = "fsl,ns16550", "ns16550";

since that enables a workaround I'd added for a hardware errata relating
to sending breaks over the serial console.   What you describe above
makes me think you aren't getting the workaround enabled.

Paul.
--

>
> http://en.wikipedia.org/wiki/Magic_SysRq_key .
>
>
>
>
> --
>
> Regards,
>  John.
>
> --
>
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