Alan, calm down.
What Linux on alpha ended up doing was having a Generic kernel, and then
the ability to compile for specific hardware.
And guess what? Linux/intel DOES THE SAME, and always has! There _is_ a
generic kernel, and it's called CONFIG_M386.
When you ask the configuration process to optimize for certain CPU's, you
lose the ability to run on some others. That has always been true: when
you choose CONFIG_M486, you lose the ability to run on i386 machines,
because then the kernel will take advantage of the fact that it _knows_
the memory management works properly.
I made a mistake in not documenting the fact that M586 means something
else these days, but you, Alan, are just going ballistic for no good
reason. Calm down, friend.
It probably _also_ makes sense to make the optimizations a bit more
specific, so that we'd have:
- completely generic (rather than calling it "386" - just say that it
is supposed to works on every ia32 machine)
- 486-specific: the current i486, with the ridiculous alignments that
that entails. Not recommended for _anything_ else than a i486.
- i486+: the old "Pentium" - works on i486 machines, but without the
stupid alignment, so it is smaller and faster on Pentium class machines
too. Doesn't require a TSC, so it works on pseudo-pentiums too. This is
apparently what you thought was "generic".
- Pentium+: requires TSC
- PentiumPro: requires TSC, conditional move instructions, and a fixed
local APIC for SMP.
Would that kind of split work for you? We could also make it _really_
specific.
The above is essentially what we have now, but I added a "i486+" entry
which is apparently what you were looking for. Ok?
Linus
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