[PATCH stable-5.4.y backport 1/2] KVM: Pass MMU notifier range flags to kvm_unmap_hva_range()

Will Deacon
2020-08-24T11:32:36Z

commit fdfe7cbd58806522e799e2a50a15aee7f2cbb7b6 upstream.

The 'flags' field of 'struct mmu_notifier_range' is used to indicate
whether invalidate_range_{start,end}() are permitted to block. In the
case of kvm_mmu_notifier_invalidate_range_start(), this field is not
forwarded on to the architecture-specific implementation of
kvm_unmap_hva_range() and therefore the backend cannot sensibly decide
whether or not to block.

Add an extra 'flags' parameter to kvm_unmap_hva_range() so that
architectures are aware as to whether or not they are permitted to block.

Cc: <stable@vger.kernel.org> # v5.4 only
Cc: Marc Zyngier <maz@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Message-Id: <20200811102725.7121-2-will@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Will Deacon <will@kernel.org>
---
arch/arm/include/asm/kvm_host.h | 2 +-
arch/arm64/include/asm/kvm_host.h | 2 +-
arch/mips/include/asm/kvm_host.h | 2 +-
arch/mips/kvm/mmu.c | 3 ++-
arch/powerpc/include/asm/kvm_host.h | 3 ++-
arch/powerpc/kvm/book3s.c | 3 ++-
arch/powerpc/kvm/e500_mmu_host.c | 3 ++-
arch/x86/include/asm/kvm_host.h | 3 ++-
arch/x86/kvm/mmu.c | 3 ++-
virt/kvm/arm/mmu.c | 2 +-
virt/kvm/kvm_main.c | 3 ++-
11 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 1b179b1f46bc..dd03d5e01a94 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -266,7 +266,7 @@ int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,

#define KVM_ARCH_WANT_MMU_NOTIFIER
int kvm_unmap_hva_range(struct kvm *kvm,
- unsigned long start, unsigned long end);
+ unsigned long start, unsigned long end, unsigned flags);
int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);

unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu);
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 0c3bd6aff6e9..d719c6b4dd81 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -427,7 +427,7 @@ int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,

#define KVM_ARCH_WANT_MMU_NOTIFIER
int kvm_unmap_hva_range(struct kvm *kvm,
- unsigned long start, unsigned long end);
+ unsigned long start, unsigned long end, unsigned flags);
int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end);
int kvm_test_age_hva(struct kvm *kvm, unsigned long hva);
diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
index 7b47a323dc23..356c61074d13 100644
--- a/arch/mips/include/asm/kvm_host.h
+++ b/arch/mips/include/asm/kvm_host.h
@@ -939,7 +939,7 @@ enum kvm_mips_fault_result kvm_trap_emul_gva_fault(struct kvm_vcpu *vcpu,

#define KVM_ARCH_WANT_MMU_NOTIFIER
int kvm_unmap_hva_range(struct kvm *kvm,
- unsigned long start, unsigned long end);
+ unsigned long start, unsigned long end, unsigned flags);
int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end);
int kvm_test_age_hva(struct kvm *kvm, unsigned long hva);
diff --git a/arch/mips/kvm/mmu.c b/arch/mips/kvm/mmu.c
index 97e538a8c1be..97f63a84aa51 100644
--- a/arch/mips/kvm/mmu.c
+++ b/arch/mips/kvm/mmu.c
@@ -512,7 +512,8 @@ static int kvm_unmap_hva_handler(struct kvm *kvm, gfn_t gfn, gfn_t gfn_end,
return 1;
}

-int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end)
+int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end,
+ unsigned flags)
{
handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler, NULL);

diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 6fe6ad64cba5..740b52ec3509 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -58,7 +58,8 @@
#define KVM_ARCH_WANT_MMU_NOTIFIER

extern int kvm_unmap_hva_range(struct kvm *kvm,
- unsigned long start, unsigned long end);
+ unsigned long start, unsigned long end,
+ unsigned flags);
extern int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end);
extern int kvm_test_age_hva(struct kvm *kvm, unsigned long hva);
extern int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index ec2547cc5ecb..1ff971f3b06f 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -867,7 +867,8 @@ void kvmppc_core_commit_memory_region(struct kvm *kvm,
kvm->arch.kvm_ops->commit_memory_region(kvm, mem, old, new, change);
}

-int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end)
+int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end,
+ unsigned flags)
{
return kvm->arch.kvm_ops->unmap_hva_range(kvm, start, end);
}
diff --git a/arch/powerpc/kvm/e500_mmu_host.c b/arch/powerpc/kvm/e500_mmu_host.c
index 321db0fdb9db..7154bd424d24 100644
--- a/arch/powerpc/kvm/e500_mmu_host.c
+++ b/arch/powerpc/kvm/e500_mmu_host.c
@@ -734,7 +734,8 @@ static int kvm_unmap_hva(struct kvm *kvm, unsigned long hva)
return 0;
}

-int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end)
+int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end,
+ unsigned flags)
{
/* kvm_unmap_hva flushes everything anyways */
kvm_unmap_hva(kvm, start);
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 742de9d97ba1..c41686641c3f 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1553,7 +1553,8 @@ asmlinkage void kvm_spurious_fault(void);
_ASM_EXTABLE(666b, 667b)

#define KVM_ARCH_WANT_MMU_NOTIFIER
-int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end);
+int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end,
+ unsigned flags);
int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end);
int kvm_test_age_hva(struct kvm *kvm, unsigned long hva);
int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 342d9ddf35c3..bb743f956c23 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2045,7 +2045,8 @@ static int kvm_handle_hva(struct kvm *kvm, unsigned long hva,
return kvm_handle_hva_range(kvm, hva, hva + 1, data, handler);
}

-int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end)
+int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end,
+ unsigned flags)
{
return kvm_handle_hva_range(kvm, start, end, 0, kvm_unmap_rmapp);
}
diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index 767ac4eab4fe..b4a6bbadd144 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -2050,7 +2050,7 @@ static int kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *dat
}

int kvm_unmap_hva_range(struct kvm *kvm,
- unsigned long start, unsigned long end)
+ unsigned long start, unsigned long end, unsigned flags)
{
if (!kvm->arch.pgd)
return 0;
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index d5d4cd581af3..278bdc53047e 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -425,7 +425,8 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
* count is also read inside the mmu_lock critical section.
*/
kvm->mmu_notifier_count++;
- need_tlb_flush = kvm_unmap_hva_range(kvm, range->start, range->end);
+ need_tlb_flush = kvm_unmap_hva_range(kvm, range->start, range->end,
+ range->flags);
need_tlb_flush |= kvm->tlbs_dirty;
/* we've to flush the tlb before the pages can be freed */
if (need_tlb_flush)
--
2.28.0.297.g1956fa8f8d-goog