From: "Siddha, Suresh B" We need to use the size_and_mask in set_mtrr_var_ranges(which is called while programming MTRR's for AP's Signed-off-by: Suresh Siddha Signed-off-by: Andrew Morton --- 25-akpm/arch/i386/kernel/cpu/mtrr/generic.c | 6 ++++-- 1 files changed, 4 insertions(+), 2 deletions(-) diff -puN arch/i386/kernel/cpu/mtrr/generic.c~x86_64-always-use-cpuid-80000008-to-figure-out-mtrr-fix arch/i386/kernel/cpu/mtrr/generic.c --- 25/arch/i386/kernel/cpu/mtrr/generic.c~x86_64-always-use-cpuid-80000008-to-figure-out-mtrr-fix 2005-04-10 23:32:59.000000000 -0700 +++ 25-akpm/arch/i386/kernel/cpu/mtrr/generic.c 2005-04-10 23:32:59.000000000 -0700 @@ -193,7 +193,8 @@ static int set_mtrr_var_ranges(unsigned rdmsr(MTRRphysBase_MSR(index), lo, hi); if ((vr->base_lo & 0xfffff0ffUL) != (lo & 0xfffff0ffUL) - || (vr->base_hi & 0xfUL) != (hi & 0xfUL)) { + || (vr->base_hi & (size_and_mask >> (32 - PAGE_SHIFT))) != + (hi & (size_and_mask >> (32 - PAGE_SHIFT)))) { mtrr_wrmsr(MTRRphysBase_MSR(index), vr->base_lo, vr->base_hi); changed = TRUE; } @@ -201,7 +202,8 @@ static int set_mtrr_var_ranges(unsigned rdmsr(MTRRphysMask_MSR(index), lo, hi); if ((vr->mask_lo & 0xfffff800UL) != (lo & 0xfffff800UL) - || (vr->mask_hi & 0xfUL) != (hi & 0xfUL)) { + || (vr->mask_hi & (size_and_mask >> (32 - PAGE_SHIFT))) != + (hi & (size_and_mask >> (32 - PAGE_SHIFT)))) { mtrr_wrmsr(MTRRphysMask_MSR(index), vr->mask_lo, vr->mask_hi); changed = TRUE; } _