[llvmlinux] Linux-v3.10 is bootable here

Behan Webster behanw at converseincode.com
Fri Jul 12 16:23:59 UTC 2013

On 07/12/13 12:12, PaX Team wrote:
>> BTW, why do you have "-mno-sse" in x86-boot but not in x86-realmode Makefile?
> it's an oversight i think, no kernel code should be compiled without -mno-sse.
Indeed. Except in very narrow circumstances the kernel never uses any 
vector nor floating point instructions; those are left for user space to 

Were those instructions used in kernel space saving/restoring the state 
of the FPU or the various vector units when you move between kernel and 
user space would require system calls to take a lot longer than they 
already do today. And a lot of time is already spent doing so, which is 
why some processors now have specialized fast system call instructions.


Behan Webster
behanw at converseincode.com

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