Re: [PATCH] bootup: Add built-in kernel command line for x86

H. Peter Anvin
2008-08-06T23:02:58Z

Matt Mackall wrote:
> On Wed, 2008-08-06 at 15:48 -0700, H. Peter Anvin wrote:
>> Tim Bird wrote:
>>> One difficulty is that the other arches' command lines
>>> are not currently "broken", so there's no real incentive
>>> to change them.
>>>
>>> The only thing novel thing I'm adding here is the addition of
>>> the leading '!' to allow for an override. This is needed
>>> in some x86 cases I'm familiar with, but I've haven't seen
>>> any cases where it would be useful for other arches.
>>> (not to say they don't exist - I just haven't seen them.)
>>>
>> Note that it could just as easily be done with a CONFIG_CMDLINE_OVERRIDE
>> option, since the initial reason for a magic character was to be able to
>> provide both prefix and suffix splicing.
>
> You're right, I had forgotten about the suffix splicing and my brain is
> a bit foggy on what motivated it.
>

Well, prefix = bootloader overrides; suffix = builtin overrides.

>> CONFIG_CMDLINE_OVERRIDE is probably more palatable to other architectures.
>
> Yes, though I doubt we're in danger of introducing any real backwards
> compatibility issues with the magic '!' at the beginning.

Well, it does if we want to make this a generic feature, which I believe
we should.

-hpa