| Message ID | 20231108111806.92604-17-nsaenz@amazon.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: x86: hyperv: Introduce VSM support | expand |
On Wed, 2023-11-08 at 11:17 +0000, Nicolas Saenz Julienne wrote: > Include the fault's read, write and execute status when exiting to > user-space. > > Signed-off-by: Nicolas Saenz Julienne <nsaenz@amazon.com> > --- > arch/x86/kvm/mmu/mmu.c | 4 ++-- > include/linux/kvm_host.h | 9 +++++++-- > include/uapi/linux/kvm.h | 6 ++++++ > 3 files changed, 15 insertions(+), 4 deletions(-) > > diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c > index 4e02d506cc25..feca077c0210 100644 > --- a/arch/x86/kvm/mmu/mmu.c > +++ b/arch/x86/kvm/mmu/mmu.c > @@ -4300,8 +4300,8 @@ static inline u8 kvm_max_level_for_order(int order) > static void kvm_mmu_prepare_memory_fault_exit(struct kvm_vcpu *vcpu, > struct kvm_page_fault *fault) > { > - kvm_prepare_memory_fault_exit(vcpu, fault->gfn << PAGE_SHIFT, > - PAGE_SIZE, fault->write, fault->exec, > + kvm_prepare_memory_fault_exit(vcpu, fault->gfn << PAGE_SHIFT, PAGE_SIZE, > + fault->write, fault->exec, fault->user, > fault->is_private); > } > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > index 71e1e8cf8936..631fd532c97a 100644 > --- a/include/linux/kvm_host.h > +++ b/include/linux/kvm_host.h > @@ -2367,14 +2367,19 @@ static inline void kvm_account_pgtable_pages(void *virt, int nr) > static inline void kvm_prepare_memory_fault_exit(struct kvm_vcpu *vcpu, > gpa_t gpa, gpa_t size, > bool is_write, bool is_exec, > - bool is_private) > + bool is_read, bool is_private) It almost feels like there is a need for a struct to hold all of those parameters. > { > vcpu->run->exit_reason = KVM_EXIT_MEMORY_FAULT; > vcpu->run->memory_fault.gpa = gpa; > vcpu->run->memory_fault.size = size; > > - /* RWX flags are not (yet) defined or communicated to userspace. */ > vcpu->run->memory_fault.flags = 0; > + if (is_read) > + vcpu->run->memory_fault.flags |= KVM_MEMORY_EXIT_FLAG_READ; > + if (is_write) > + vcpu->run->memory_fault.flags |= KVM_MEMORY_EXIT_FLAG_WRITE; > + if (is_exec) > + vcpu->run->memory_fault.flags |= KVM_MEMORY_EXIT_FLAG_EXECUTE; > if (is_private) > vcpu->run->memory_fault.flags |= KVM_MEMORY_EXIT_FLAG_PRIVATE; > } > diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h > index 03f5c08fd7aa..0ddffb8b0c99 100644 > --- a/include/uapi/linux/kvm.h > +++ b/include/uapi/linux/kvm.h > @@ -533,7 +533,13 @@ struct kvm_run { > } notify; > /* KVM_EXIT_MEMORY_FAULT */ > struct { > +#define KVM_MEMORY_EXIT_FLAG_READ (1ULL << 0) > +#define KVM_MEMORY_EXIT_FLAG_WRITE (1ULL << 1) > +#define KVM_MEMORY_EXIT_FLAG_EXECUTE (1ULL << 2) > #define KVM_MEMORY_EXIT_FLAG_PRIVATE (1ULL << 3) > +#define KVM_MEMORY_EXIT_NO_ACCESS \ > + (KVM_MEMORY_EXIT_FLAG_NR | KVM_MEMORY_EXIT_FLAG_NW | \ > + KVM_MEMORY_EXIT_FLAG_NX) > __u64 flags; > __u64 gpa; > __u64 size; I don't think that KVM_MEMORY_EXIT_FLAG_NR, KVM_MEMORY_EXIT_FLAG_NW, KVM_MEMORY_EXIT_FLAG_NX are defined anywhere. Also why KVM_MEMORY_EXIT_NO_ACCESS is needed - userspace can infer it from the lack of other access flags. Best regards, Maxim Levitsky
On Tue, Nov 28, 2023, Maxim Levitsky wrote: > On Wed, 2023-11-08 at 11:17 +0000, Nicolas Saenz Julienne wrote: > > Include the fault's read, write and execute status when exiting to > > user-space. > > > > Signed-off-by: Nicolas Saenz Julienne <nsaenz@amazon.com> > > --- > > arch/x86/kvm/mmu/mmu.c | 4 ++-- > > include/linux/kvm_host.h | 9 +++++++-- > > include/uapi/linux/kvm.h | 6 ++++++ > > 3 files changed, 15 insertions(+), 4 deletions(-) > > > > diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c > > index 4e02d506cc25..feca077c0210 100644 > > --- a/arch/x86/kvm/mmu/mmu.c > > +++ b/arch/x86/kvm/mmu/mmu.c > > @@ -4300,8 +4300,8 @@ static inline u8 kvm_max_level_for_order(int order) > > static void kvm_mmu_prepare_memory_fault_exit(struct kvm_vcpu *vcpu, > > struct kvm_page_fault *fault) > > { > > - kvm_prepare_memory_fault_exit(vcpu, fault->gfn << PAGE_SHIFT, > > - PAGE_SIZE, fault->write, fault->exec, > > + kvm_prepare_memory_fault_exit(vcpu, fault->gfn << PAGE_SHIFT, PAGE_SIZE, > > + fault->write, fault->exec, fault->user, > > fault->is_private); > > } > > > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > > index 71e1e8cf8936..631fd532c97a 100644 > > --- a/include/linux/kvm_host.h > > +++ b/include/linux/kvm_host.h > > @@ -2367,14 +2367,19 @@ static inline void kvm_account_pgtable_pages(void *virt, int nr) > > static inline void kvm_prepare_memory_fault_exit(struct kvm_vcpu *vcpu, > > gpa_t gpa, gpa_t size, > > bool is_write, bool is_exec, > > - bool is_private) > > + bool is_read, bool is_private) > > It almost feels like there is a need for a struct to hold all of those parameters. The most obvious solution would be to make "struct kvm_page_fault" common, e.g. ARM's user_mem_abort() fills RWX booleans just like x86 fills kvm_page_fault. But I think it's best to wait to do something like that until after Anish's series lands[*]. That way the conversion can be more of a pure refactoring. [*] https://lore.kernel.org/all/20231109210325.3806151-1-amoorthy@google.com
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 4e02d506cc25..feca077c0210 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -4300,8 +4300,8 @@ static inline u8 kvm_max_level_for_order(int order) static void kvm_mmu_prepare_memory_fault_exit(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) { - kvm_prepare_memory_fault_exit(vcpu, fault->gfn << PAGE_SHIFT, - PAGE_SIZE, fault->write, fault->exec, + kvm_prepare_memory_fault_exit(vcpu, fault->gfn << PAGE_SHIFT, PAGE_SIZE, + fault->write, fault->exec, fault->user, fault->is_private); } diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 71e1e8cf8936..631fd532c97a 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -2367,14 +2367,19 @@ static inline void kvm_account_pgtable_pages(void *virt, int nr) static inline void kvm_prepare_memory_fault_exit(struct kvm_vcpu *vcpu, gpa_t gpa, gpa_t size, bool is_write, bool is_exec, - bool is_private) + bool is_read, bool is_private) { vcpu->run->exit_reason = KVM_EXIT_MEMORY_FAULT; vcpu->run->memory_fault.gpa = gpa; vcpu->run->memory_fault.size = size; - /* RWX flags are not (yet) defined or communicated to userspace. */ vcpu->run->memory_fault.flags = 0; + if (is_read) + vcpu->run->memory_fault.flags |= KVM_MEMORY_EXIT_FLAG_READ; + if (is_write) + vcpu->run->memory_fault.flags |= KVM_MEMORY_EXIT_FLAG_WRITE; + if (is_exec) + vcpu->run->memory_fault.flags |= KVM_MEMORY_EXIT_FLAG_EXECUTE; if (is_private) vcpu->run->memory_fault.flags |= KVM_MEMORY_EXIT_FLAG_PRIVATE; } diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 03f5c08fd7aa..0ddffb8b0c99 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -533,7 +533,13 @@ struct kvm_run { } notify; /* KVM_EXIT_MEMORY_FAULT */ struct { +#define KVM_MEMORY_EXIT_FLAG_READ (1ULL << 0) +#define KVM_MEMORY_EXIT_FLAG_WRITE (1ULL << 1) +#define KVM_MEMORY_EXIT_FLAG_EXECUTE (1ULL << 2) #define KVM_MEMORY_EXIT_FLAG_PRIVATE (1ULL << 3) +#define KVM_MEMORY_EXIT_NO_ACCESS \ + (KVM_MEMORY_EXIT_FLAG_NR | KVM_MEMORY_EXIT_FLAG_NW | \ + KVM_MEMORY_EXIT_FLAG_NX) __u64 flags; __u64 gpa; __u64 size;
Include the fault's read, write and execute status when exiting to user-space. Signed-off-by: Nicolas Saenz Julienne <nsaenz@amazon.com> --- arch/x86/kvm/mmu/mmu.c | 4 ++-- include/linux/kvm_host.h | 9 +++++++-- include/uapi/linux/kvm.h | 6 ++++++ 3 files changed, 15 insertions(+), 4 deletions(-)