Re: Various x86 syscall mechanisms

[Bill Davidsen <davidsen@tmr.com>]

Roland McGrath wrote:
>> As far as I can work out, an x86_32 kernel will use "int 0x80" and 
>> "sysenter" for system calls.  64-bit kernel will use just "syscall" for 
>> 64-bit processes (though you can use "int 0x80" to access the 32-bit 
>> syscall interface from a 64-bit process), but will allow "sysenter", 
>> "syscall" or "int 0x80" for 32-on-64 processes.
> 
> That is correct, with the caveats below.
> 
Thanks for setting this out clearly, I've seen most of it (from Andi, I 
think) in bits, and one of the scheduler folk had a comment relevant to 
scheduling which I can't find now, but this is both technical and 
historical, and thus a nice thing to hand to someone with a related 
question.

Well done.

-- 
Bill Davidsen <davidsen@tmr.com>
   "We have more to fear from the bungling of the incompetent than from
the machinations of the wicked."  - from Slashdot