Re: [PATCH] PCI: Add pci=safemode option

[Greg Kroah-Hartman]

On Wed, May 30, 2018 at 12:44:29AM -0700, okaya@xxxxxxxxxxxxxx wrote:
> On 2018-05-30 00:37, Christoph Hellwig wrote:
> > On Tue, May 29, 2018 at 09:41:33PM -0700, Sinan Kaya wrote:
> > > Bjorn and I discussed the need for such a "safe" mode feature when you
> > > want to bring up PCI for a platform. You want to turn off everything
> > > as
> > > a starter and just stick to bare minimum.
> > 
> > Can we please make it a config option the instead of adding code
> > to every kernel?  Also maybe the bringup should be in the name
> > to make this more clear?
> 
> One other requirement was to have a runtime option rather than compile time
> option.
> 
> When someone reported a problem, we wanted to be able to say "use this
> option and see if system boots" without doing any bisects or recompilation.
> 
> This would be the first step in troubleshooting a system to see if
> fundamental features are working.

That makes sense, people can not rebuild their kernels for the most
part.  Putting it behind a config option would not make sense as it
would always have to be enabled.

> I don't mind changing the name Bjorn mentioned safe option. I made it
> safemode. I am looking at Bjorn for suggestions at this moment.

"minimal"?  "basic"?  "crippled"?
"my_hardware_is_so_borked_it_needs_this_option"?  :)

Naming is hard...

greg k-h