x86: Fix booting with "no387 nofxsr"
Jesper Juhl reported that testing the software math-emulation by forcing "no387" doesn't work on modern CPU's. The reason was two-fold: - you also need to pass in "nofxsr" to make sure that we not only don't touch the old i387 legacy hardware, it also needs to disable the modern XMM/FXSR sequences - "nofxsr" didn't actually clear the capability bits immediately, leaving the early boot sequence still using FXSR until we got to the identify_cpu() stage. This fixes the "nofxsr" flag to take effect immediately on the boot CPU. Debugging by Randy Dunlap Acked-by: Randy Dunlap <firstname.lastname@example.org> Cc: Jesper Juhl <email@example.com> Cc: Andi Kleen <firstname.lastname@example.org> Signed-off-by: Linus Torvalds <email@example.com>
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