cvs commit: src/sys/amd64/amd64 mp_machdep.csrc/sys/amd64/include cpufunc.h src/sys/i386/i386 mp_machdep.c src/sys/i386/include cpufunc.h

[Colin Percival]

Alexey Dokuchaev wrote:
> On Fri, May 13, 2005 at 12:01:20AM +0000, Jacques Vidrine wrote:
>>  Add a knob for disabling/enabling HTT, "machdep.hyperthreading_allowed".
>>  Default off due to information disclosure on multi-user systems.
> 
> Why not name it "machdep.hyperthreading_enabled" or even "machdep.htt_enabled"
> for consistency with other ones?

I was aiming for consistency with other security-related knobs:

security.jail.set_hostname_allowed
security.jail.sysvipc_allowed
security.jail.chflags_allowed

I ended up putting hyperthreading_allowed under machdep rather than security
because 4.x doesn't have a security sysctl node, but the name was chosen to
emphasize that hyperthreading is currently something dangerous which should
be permitted only under certain circumstances, rather than a feature which
can be enabled or disabled however you like.

Colin Percival