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author | Xiao Guangrong <guangrong.xiao@intel.com> | 2015-07-16 03:25:54 +0800 |
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committer | Paolo Bonzini <pbonzini@redhat.com> | 2015-07-23 08:21:33 +0200 |
commit | 10dc331ff5e7e4668c0f0c95b1a873aba9b70826 (patch) | |
tree | 969d2dea497daa3132ec97647b6c55048e4edc84 /arch/x86/kvm/mtrr.c | |
parent | c5dfd654d0ec0a28fe81e7bd4d4fd984a9855e09 (diff) | |
download | linux-stable-10dc331ff5e7e4668c0f0c95b1a873aba9b70826.tar.gz linux-stable-10dc331ff5e7e4668c0f0c95b1a873aba9b70826.tar.bz2 linux-stable-10dc331ff5e7e4668c0f0c95b1a873aba9b70826.zip |
KVM: MTRR: fix memory type handling if MTRR is completely disabled
Currently code uses default memory type if MTRR is fully disabled,
fix it by using UC instead.
Signed-off-by: Xiao Guangrong <guangrong.xiao@intel.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/mtrr.c')
-rw-r--r-- | arch/x86/kvm/mtrr.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/arch/x86/kvm/mtrr.c b/arch/x86/kvm/mtrr.c index de1d2d8062e2..e2750134a22b 100644 --- a/arch/x86/kvm/mtrr.c +++ b/arch/x86/kvm/mtrr.c @@ -120,6 +120,16 @@ static u8 mtrr_default_type(struct kvm_mtrr *mtrr_state) return mtrr_state->deftype & IA32_MTRR_DEF_TYPE_TYPE_MASK; } +static u8 mtrr_disabled_type(void) +{ + /* + * Intel SDM 11.11.2.2: all MTRRs are disabled when + * IA32_MTRR_DEF_TYPE.E bit is cleared, and the UC + * memory type is applied to all of physical memory. + */ + return MTRR_TYPE_UNCACHABLE; +} + /* * Three terms are used in the following code: * - segment, it indicates the address segments covered by fixed MTRRs. @@ -434,6 +444,8 @@ struct mtrr_iter { /* output fields. */ int mem_type; + /* mtrr is completely disabled? */ + bool mtrr_disabled; /* [start, end) is not fully covered in MTRRs? */ bool partial_map; @@ -549,7 +561,7 @@ static void mtrr_lookup_var_next(struct mtrr_iter *iter) static void mtrr_lookup_start(struct mtrr_iter *iter) { if (!mtrr_is_enabled(iter->mtrr_state)) { - iter->partial_map = true; + iter->mtrr_disabled = true; return; } @@ -563,6 +575,7 @@ static void mtrr_lookup_init(struct mtrr_iter *iter, iter->mtrr_state = mtrr_state; iter->start = start; iter->end = end; + iter->mtrr_disabled = false; iter->partial_map = false; iter->fixed = false; iter->range = NULL; @@ -656,6 +669,9 @@ u8 kvm_mtrr_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn) return MTRR_TYPE_WRBACK; } + if (iter.mtrr_disabled) + return mtrr_disabled_type(); + /* It is not covered by MTRRs. */ if (iter.partial_map) { /* @@ -689,6 +705,9 @@ bool kvm_mtrr_check_gfn_range_consistency(struct kvm_vcpu *vcpu, gfn_t gfn, return false; } + if (iter.mtrr_disabled) + return true; + if (!iter.partial_map) return true; |