« Previous | Next » 

Revision df07ec56

IDdf07ec5626b9dc7901ae49286cdb0d4f5d9187ce

Added by Eduardo Habkost about 12 years ago

cpu defs: remove replicated flags from Intel (v2)

This patch removes the replicated feature flags from cpuid 8000_0001:edx
(extfeature_edx) from Intel models, as the duplicated feature flags are present
only on AMD CPUs. On Intel models, only the i64, syscall, and xd flags are kept
on extfeature_edx.

This is based on a previous patch from John Cooper where this was introduced
with many other changes at the same time. Original John's patch submission is
at Message-ID: <>, <http://marc.info/?l=qemu-devel&m=130618871926030>.

Original John's patch description was:

cpu model bug fixes and definition corrections
This patch was intended to address the replicated feature
flags in cpuid 8000_0001:edx from cpuid 0000_0001:edx.
This is due to AMD's definition where these flags are
mostly cloned in the 8000_0001:edx cpuid function.
qemu64 attempted to glue together the respective Intel
and AMD nearly disjoint features and this propagated to
the new Intel models as doing so was believed conservative
at the time. However after further soak and test lugging
around this cruft doesn't provide any value, could
conceivably confuse a guest, and has confused users trying
to maintain/add cpu definitions. This also caused issues
for libvirt attempting to track this mis-encoding.
So we've here tossed out the AMD replicated definitions
from the Intel models, added a few replications into AMD
definitions which were missing according to AMD's latest
CPUID document, and reordered the config file flags to
follow intuitive sequential bit ordering. Also two flag
name aliases were added for clarity to Intel models. The
end result being the models definitions now conform to
their respective cpuid specifications sans x2apic which is
emulated by kvm.
This was tested with the following combinations:
[Conroe, Penryn, Nehalem] x [F12-64, win64, win32] -- Intel host
[Opteron_G1, Opteron_G2, Opteron_G3] x [F12-64, win64, win32] -- AMD host
Yielding successful boots in all cases.
Signed-off-by: john cooper &lt;&gt;

Changes v1 -> v2:
- Rebase against latest Qemu git tree

Signed-off-by: Eduardo Habkost <>
Signed-off-by: Anthony Liguori <>

Files

  • added
  • modified
  • copied
  • renamed
  • deleted

View differences