[PATCH 3.16 061/125] Revert "KVM: x86: Increase the number of fixed MTRR regs to 10"

Greg Kroah-Hartman
2014-09-03T23:09:47Z

From: Paolo Bonzini <pbonzini@redhat.com>

commit 0d234daf7e0a3290a3a20c8087eefbd6335a5bd4 upstream.

This reverts commit 682367c494869008eb89ef733f196e99415ae862,
which causes 32-bit SMP Windows 7 guests to panic.

SeaBIOS has a limit on the number of MTRRs that it can handle,
and this patch exceeded the limit. Better revert it.
Thanks to Nadav Amit for debugging the cause.

Reported-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/x86/include/asm/kvm_host.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -95,7 +95,7 @@ static inline gfn_t gfn_to_index(gfn_t g
#define KVM_REFILL_PAGES 25
#define KVM_MAX_CPUID_ENTRIES 80
#define KVM_NR_FIXED_MTRR_REGION 88
-#define KVM_NR_VAR_MTRR 10
+#define KVM_NR_VAR_MTRR 8

#define ASYNC_PF_PER_VCPU 64