KVM: MTRR: fix fixed MTRR segment look up
KVM: MTRR: fix fixed MTRR segment look up

This fixes the slow-down of VM running with pci-passthrough, since some MTRR
range changed from MTRR_TYPE_WRBACK to MTRR_TYPE_UNCACHABLE.  Memory in the
0K-640K range was incorrectly treated as uncacheable.

Fixes: f7bfb57b3e89ff89c0da9f93dedab89f68d6ca27
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=107561
Cc: bca990786fdd594f74b06d1895667e8b842f63ee@nongnu.org
Signed-off-by: Alexis Dambricourt <de3fd8327394465fe979d1277f55efdf7d7e9966@gmail.com>
[Use correct BZ for "Fixes" annotation.  - Paolo]
Signed-off-by: Paolo Bonzini <69d3ebcf5ee4e7f05a50dc23cd96655b730804b4@redhat.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs