[PATCH] PCI: Add pci=safemode option

[okaya@codeaurora.org (okaya at codeaurora.org)]

On 2018-05-30 00:56, okaya at codeaurora.org wrote:
> On 2018-05-30 00:48, Greg Kroah-Hartman wrote:
>> On Wed, May 30, 2018 at 12:44:29AM -0700, okaya at codeaurora.org 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.
>> 
> 
> Here is where the discussion took place. Last 5-10  messages should 
> help.
> 
> 
> https://bugzilla.kernel.org/show_bug.cgi?id=196197
> 

Some more paper trail for general awareness.

https://lkml.org/lkml/2018/5/3/509

> 
>>> 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