Re: [RFC GIT PULL] "Nuke 386-DX/SX support" changes for v3.8

[Florian Fainelli]

Le 12/12/12 19:04, Linus Torvalds a Ãcrit :
> On Tue, Dec 11, 2012 at 3:10 AM, Ingo Molnar <mingo@xxxxxxxxxx> wrote:
> > This tree removes ancient-386-CPUs support and thus zaps quite a
> > bit of complexity:
>
> Btw, I think we should probably at least consider taking this one step
> further, and remove the dear old FPU emulation support too. Remove
> CONFIG_MATH_EMULATION and all of arch/x86/math-emu, along with a lot
> of small special cases.
>
> Or do people still use the 486SX?

Yes, the RDC-R321x SoC which is supported by mainline actually needs 
Math emulation to properly work.

> Now, the math emulation hasn't been all that fundamentally problematic
> (compared to lack of xadd etc), but it does result in some
> complexities in exception handling and ptrace (grep for HAVE_HWFP or
> "hard_math" or a number of other magic things). None of which have
> likely been tested at all in the last ten years, so who knows if it
> actually *works* or not.
>
> Maybe somebody could try booting with "no387". Does it actually work?

Ok, I could try that.
--
Florian
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