[Skiboot] [PATCH 1/4] fsp/console: Ignore data on unresponsive consoles

[Samuel Mendoza-Jonas]

On Fri, 2016-07-15 at 15:18 +1000, Stewart Smith wrote:
> Samuel Mendoza-Jonas <sam at mendozajonas.com> writes:
> > 
> > Linux kernels from v4.1 onwards will try to request an irq for each hvc
> > console using OPAL_EVENT_CONSOLE_INPUT, however because the IRQF_SHARED
> > flag is not set any console after the first will fail. If there is data
> > on one of these failed consoles OPAL will set OPAL_EVENT_CONSOLE_INPUT
> > every time fsp_console_read is called, leading to RCU stalls in the
> > kernel.
> > 
> > As a workaround for unpatched kernels, cease setting
> > OPAL_EVENT_CONSOLE_INPUT for consoles that we have noticed are not being
> > read.
> > 
> > Signed-off-by: Samuel Mendoza-Jonas <sam at mendozajonas.com>
> 
> Thanks, merged to master as of fd6b71fcc6912611ce81f455b4805f0531699d5e
> and 5.2.x as of 7116c948ee63019ceda7dc3b7334e6c25e291eeb
> 
> This does *slightly* change the API, but it turns out pretty much none
> of it is documented anyway :/
> 

Did you have any thoughts on the other three (non-stable) patches of this
series?

Cheers,
Sam