James Sutherland <jas88@cam.ac.uk> writes:
[FDIV errors on pentiums]
> > So what does the kernel (can) do to prevent this problem on defective
> > pentiums?
>
> Trap the defective instructions, and implement a replacement instruction
> in software. On later Intel CPUs, you can sometimes use a microcode update
> to fix it - this also requires OS intervention.
>
> Either way, essentially you tell the OS to block the duff instructions,
> and it does so.
Have you bothered to check this, or it's just a guess?
The truth is that the kernel does exactly nothing except printing
warning message about defective FPU. It's up to the application
to deal with the problem. Yes, it would be possible for the kernel
to check all executed instructions - guess why it doesn't do that?
The bug is only present on some non-MMX Pentium CPUs, they have no
updatable (nor downloadable) microcode.
-- Krzysztof Halasa Network Administrator- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Mon Jul 31 2000 - 21:00:22 EST