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Re: Bug#111581: [bcollins@debian.org: Bug#111581: what to do about umul instructions and old SPARC boxen]

> >cpu             : Cypress/ROSS CY7C601
> I think that is indeed a SPARCv7 chip.  Looks like the "sun4m implies
> sparcv8" rule is not entirely hard and fast.
> Globally enabling kernel emulation of umul for sun4m shouldn't do any
> harm, so that seems like the best approach.  Or, if one wanted to be
> really careful, the kernel does know the exact cpu model so the
> emulation could be enabled only for those Cypress parts.

Maybe, kernel should test for [us]mul in the illegal instruction trap 
handler, and if detected emulate those instructions, increase instruction 
counter and return from the trap ?

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