diff options
| author | Xiao Guangrong <guangrong.xiao@linux.intel.com> | 2015-05-13 09:42:19 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2015-05-19 21:52:42 +0300 |
| commit | d69afbc6b1b5d0579f13d1a6339d952c4f60a9f4 (patch) | |
| tree | 6b277abdcd5c8801a1c29c849cda0011e9b77c9b /arch | |
| parent | 6a49f85c7ac83c1918d138d40492a5cef40b5ff8 (diff) | |
| download | linux-d69afbc6b1b5d0579f13d1a6339d952c4f60a9f4.tar.xz | |
KVM: MMU: fix decoding cache type from MTRR
There are some bugs in current get_mtrr_type();
1: bit 1 of mtrr_state->enabled is corresponding bit 11 of
IA32_MTRR_DEF_TYPE MSR which completely control MTRR's enablement
that means other bits are ignored if it is cleared
2: the fixed MTRR ranges are controlled by bit 0 of
mtrr_state->enabled (bit 10 of IA32_MTRR_DEF_TYPE)
3: if MTRR is disabled, UC is applied to all of physical memory rather
than mtrr_state->def_type
Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Reviewed-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/mmu.c | 14 |
1 files changed, 6 insertions, 8 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index ddf25f39735a..e718c76609f9 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -2431,19 +2431,20 @@ EXPORT_SYMBOL_GPL(kvm_mmu_unprotect_page); static int get_mtrr_type(struct mtrr_state_type *mtrr_state, u64 start, u64 end) { - int i; u64 base, mask; u8 prev_match, curr_match; - int num_var_ranges = KVM_NR_VAR_MTRR; + int i, num_var_ranges = KVM_NR_VAR_MTRR; - if (!mtrr_state->enabled) - return 0xFF; + /* MTRR is completely disabled, use UC for all of physical memory. */ + if (!(mtrr_state->enabled & 0x2)) + return MTRR_TYPE_UNCACHABLE; /* Make end inclusive end, instead of exclusive */ end--; /* Look in fixed ranges. Just return the type as per start */ - if (mtrr_state->have_fixed && (start < 0x100000)) { + if (mtrr_state->have_fixed && (mtrr_state->enabled & 0x1) && + (start < 0x100000)) { int idx; if (start < 0x80000) { @@ -2466,9 +2467,6 @@ static int get_mtrr_type(struct mtrr_state_type *mtrr_state, * Look of multiple ranges matching this address and pick type * as per MTRR precedence */ - if (!(mtrr_state->enabled & 2)) - return mtrr_state->def_type; - prev_match = 0xFF; for (i = 0; i < num_var_ranges; ++i) { unsigned short start_state, end_state; |