[PATCH 01/10] KVM: SVM: Don't use kmap_atomic in nested_svm_map

[Joerg Roedel]

Use of kmap_atomic disables preemption but if we run in
shadow-shadow mode the vmrun emulation executes kvm_set_cr3
which might sleep or fault. So use kmap instead for
nested_svm_map.

Cc: stable@xxxxxxxxxx
Signed-off-by: Joerg Roedel <joerg.roedel@xxxxxxx>
---
 arch/x86/kvm/svm.c |   32 ++++++++++++++++----------------
 1 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 52f78dd..041ef6f 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1417,7 +1417,7 @@ static inline int nested_svm_intr(struct vcpu_svm *svm)
 	return 0;
 }
 
-static void *nested_svm_map(struct vcpu_svm *svm, u64 gpa, enum km_type idx)
+static void *nested_svm_map(struct vcpu_svm *svm, u64 gpa)
 {
 	struct page *page;
 
@@ -1425,7 +1425,7 @@ static void *nested_svm_map(struct vcpu_svm *svm, u64 gpa, enum km_type idx)
 	if (is_error_page(page))
 		goto error;
 
-	return kmap_atomic(page, idx);
+	return kmap(page);
 
 error:
 	kvm_release_page_clean(page);
@@ -1434,7 +1434,7 @@ error:
 	return NULL;
 }
 
-static void nested_svm_unmap(void *addr, enum km_type idx)
+static void nested_svm_unmap(void *addr)
 {
 	struct page *page;
 
@@ -1443,7 +1443,7 @@ static void nested_svm_unmap(void *addr, enum km_type idx)
 
 	page = kmap_atomic_to_page(addr);
 
-	kunmap_atomic(addr, idx);
+	kunmap(addr);
 	kvm_release_page_dirty(page);
 }
 
@@ -1458,7 +1458,7 @@ static bool nested_svm_exit_handled_msr(struct vcpu_svm *svm)
 	if (!(svm->nested.intercept & (1ULL << INTERCEPT_MSR_PROT)))
 		return false;
 
-	msrpm = nested_svm_map(svm, svm->nested.vmcb_msrpm, KM_USER0);
+	msrpm = nested_svm_map(svm, svm->nested.vmcb_msrpm);
 
 	if (!msrpm)
 		goto out;
@@ -1486,7 +1486,7 @@ static bool nested_svm_exit_handled_msr(struct vcpu_svm *svm)
 	ret = msrpm[t1] & ((1 << param) << t0);
 
 out:
-	nested_svm_unmap(msrpm, KM_USER0);
+	nested_svm_unmap(msrpm);
 
 	return ret;
 }
@@ -1616,7 +1616,7 @@ static int nested_svm_vmexit(struct vcpu_svm *svm)
 				       vmcb->control.exit_int_info,
 				       vmcb->control.exit_int_info_err);
 
-	nested_vmcb = nested_svm_map(svm, svm->nested.vmcb, KM_USER0);
+	nested_vmcb = nested_svm_map(svm, svm->nested.vmcb);
 	if (!nested_vmcb)
 		return 1;
 
@@ -1706,7 +1706,7 @@ static int nested_svm_vmexit(struct vcpu_svm *svm)
 	/* Exit nested SVM mode */
 	svm->nested.vmcb = 0;
 
-	nested_svm_unmap(nested_vmcb, KM_USER0);
+	nested_svm_unmap(nested_vmcb);
 
 	kvm_mmu_reset_context(&svm->vcpu);
 	kvm_mmu_load(&svm->vcpu);
@@ -1719,7 +1719,7 @@ static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm)
 	u32 *nested_msrpm;
 	int i;
 
-	nested_msrpm = nested_svm_map(svm, svm->nested.vmcb_msrpm, KM_USER0);
+	nested_msrpm = nested_svm_map(svm, svm->nested.vmcb_msrpm);
 	if (!nested_msrpm)
 		return false;
 
@@ -1728,7 +1728,7 @@ static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm)
 
 	svm->vmcb->control.msrpm_base_pa = __pa(svm->nested.msrpm);
 
-	nested_svm_unmap(nested_msrpm, KM_USER0);
+	nested_svm_unmap(nested_msrpm);
 
 	return true;
 }
@@ -1739,7 +1739,7 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm)
 	struct vmcb *hsave = svm->nested.hsave;
 	struct vmcb *vmcb = svm->vmcb;
 
-	nested_vmcb = nested_svm_map(svm, svm->vmcb->save.rax, KM_USER0);
+	nested_vmcb = nested_svm_map(svm, svm->vmcb->save.rax);
 	if (!nested_vmcb)
 		return false;
 
@@ -1851,7 +1851,7 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm)
 	svm->vmcb->control.event_inj = nested_vmcb->control.event_inj;
 	svm->vmcb->control.event_inj_err = nested_vmcb->control.event_inj_err;
 
-	nested_svm_unmap(nested_vmcb, KM_USER0);
+	nested_svm_unmap(nested_vmcb);
 
 	enable_gif(svm);
 
@@ -1884,12 +1884,12 @@ static int vmload_interception(struct vcpu_svm *svm)
 	svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
 	skip_emulated_instruction(&svm->vcpu);
 
-	nested_vmcb = nested_svm_map(svm, svm->vmcb->save.rax, KM_USER0);
+	nested_vmcb = nested_svm_map(svm, svm->vmcb->save.rax);
 	if (!nested_vmcb)
 		return 1;
 
 	nested_svm_vmloadsave(nested_vmcb, svm->vmcb);
-	nested_svm_unmap(nested_vmcb, KM_USER0);
+	nested_svm_unmap(nested_vmcb);
 
 	return 1;
 }
@@ -1904,12 +1904,12 @@ static int vmsave_interception(struct vcpu_svm *svm)
 	svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
 	skip_emulated_instruction(&svm->vcpu);
 
-	nested_vmcb = nested_svm_map(svm, svm->vmcb->save.rax, KM_USER0);
+	nested_vmcb = nested_svm_map(svm, svm->vmcb->save.rax);
 	if (!nested_vmcb)
 		return 1;
 
 	nested_svm_vmloadsave(svm->vmcb, nested_vmcb);
-	nested_svm_unmap(nested_vmcb, KM_USER0);
+	nested_svm_unmap(nested_vmcb);
 
 	return 1;
 }
-- 
1.6.6


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