From: Sean Christopherson sean.j.christopherson@intel.com
mainline inclusion from mainline-v5.1-rc1 commit 5192f9b976f9687569a90602b8a6c053da4498f6 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I4MKP4 CVE: NA
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KVM currently uses an 'unsigned int' for the MMIO generation number despite it being derived from the 64-bit memslots generation and being propagated to (potentially) 64-bit sptes. There is no hidden agenda behind using an 'unsigned int', it's done simply because the MMIO generation will never set bits above bit 19.
Passing a u64 will allow the "update in-progress" flag to be relocated from bit 0 to bit 63 and removes the need to cast the generation back to a u64 when propagating it to a spte.
Signed-off-by: Sean Christopherson sean.j.christopherson@intel.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Jackie Liu liuyun01@kylinos.cn Signed-off-by: Laibin Qiu qiulaibin@huawei.com --- arch/x86/kvm/mmu.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index eddf91a0e363..a7d3aa4c59bb 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -349,20 +349,20 @@ static inline bool is_access_track_spte(u64 spte) #define MMIO_GEN_LOW_MASK ((1 << MMIO_GEN_LOW_SHIFT) - 2) #define MMIO_GEN_MASK ((1 << MMIO_GEN_SHIFT) - 1)
-static u64 generation_mmio_spte_mask(unsigned int gen) +static u64 generation_mmio_spte_mask(u64 gen) { u64 mask;
WARN_ON(gen & ~MMIO_GEN_MASK);
mask = (gen & MMIO_GEN_LOW_MASK) << MMIO_SPTE_GEN_LOW_SHIFT; - mask |= ((u64)gen >> MMIO_GEN_LOW_SHIFT) << MMIO_SPTE_GEN_HIGH_SHIFT; + mask |= (gen >> MMIO_GEN_LOW_SHIFT) << MMIO_SPTE_GEN_HIGH_SHIFT; return mask; }
-static unsigned int get_mmio_spte_generation(u64 spte) +static u64 get_mmio_spte_generation(u64 spte) { - unsigned int gen; + u64 gen;
spte &= ~shadow_mmio_mask;
@@ -371,7 +371,7 @@ static unsigned int get_mmio_spte_generation(u64 spte) return gen; }
-static unsigned int kvm_current_mmio_generation(struct kvm_vcpu *vcpu) +static u64 kvm_current_mmio_generation(struct kvm_vcpu *vcpu) { return kvm_vcpu_memslots(vcpu)->generation & MMIO_GEN_MASK; } @@ -379,7 +379,7 @@ static unsigned int kvm_current_mmio_generation(struct kvm_vcpu *vcpu) static void mark_mmio_spte(struct kvm_vcpu *vcpu, u64 *sptep, u64 gfn, unsigned access) { - unsigned int gen = kvm_current_mmio_generation(vcpu); + u64 gen = kvm_current_mmio_generation(vcpu); u64 mask = generation_mmio_spte_mask(gen); u64 gpa = gfn << PAGE_SHIFT;
@@ -427,7 +427,7 @@ static bool set_mmio_spte(struct kvm_vcpu *vcpu, u64 *sptep, gfn_t gfn,
static bool check_mmio_spte(struct kvm_vcpu *vcpu, u64 spte) { - unsigned int kvm_gen, spte_gen; + u64 kvm_gen, spte_gen;
kvm_gen = kvm_current_mmio_generation(vcpu); spte_gen = get_mmio_spte_generation(spte);