From 7597f129d8b6799da7a264e6d6f7401668d3a36d Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Fri, 19 Feb 2010 16:23:00 +0100 Subject: [PATCH] KVM: SVM: Don't use kmap_atomic in nested_svm_map 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@kernel.org Signed-off-by: Joerg Roedel Signed-off-by: Avi Kivity --- arch/x86/kvm/svm.c | 47 +++++++++++++++++++++++----------------------- 1 file changed, 24 insertions(+), 23 deletions(-) diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 77fa2e3053b5..f9da35b06ec7 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -1423,7 +1423,7 @@ 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) { struct page *page; @@ -1431,7 +1431,9 @@ 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); + *_page = page; + + return kmap(page); error: kvm_release_page_clean(page); @@ -1440,16 +1442,9 @@ error: return NULL; } -static void nested_svm_unmap(void *addr, enum km_type idx) +static void nested_svm_unmap(struct page *page) { - struct page *page; - - if (!addr) - return; - - page = kmap_atomic_to_page(addr); - - kunmap_atomic(addr, idx); + kunmap(page); kvm_release_page_dirty(page); } @@ -1457,6 +1452,7 @@ static bool nested_svm_exit_handled_msr(struct vcpu_svm *svm) { u32 param = svm->vmcb->control.exit_info_1 & 1; u32 msr = svm->vcpu.arch.regs[VCPU_REGS_RCX]; + struct page *page; bool ret = false; u32 t0, t1; u8 *msrpm; @@ -1464,7 +1460,7 @@ 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, &page); if (!msrpm) goto out; @@ -1492,7 +1488,7 @@ 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(page); return ret; } @@ -1615,6 +1611,7 @@ static int nested_svm_vmexit(struct vcpu_svm *svm) struct vmcb *nested_vmcb; struct vmcb *hsave = svm->nested.hsave; struct vmcb *vmcb = svm->vmcb; + struct page *page; trace_kvm_nested_vmexit_inject(vmcb->control.exit_code, vmcb->control.exit_info_1, @@ -1622,7 +1619,7 @@ 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, &page); if (!nested_vmcb) return 1; @@ -1712,7 +1709,7 @@ 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(page); kvm_mmu_reset_context(&svm->vcpu); kvm_mmu_load(&svm->vcpu); @@ -1723,9 +1720,10 @@ static int nested_svm_vmexit(struct vcpu_svm *svm) static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm) { u32 *nested_msrpm; + struct page *page; int i; - nested_msrpm = nested_svm_map(svm, svm->nested.vmcb_msrpm, KM_USER0); + nested_msrpm = nested_svm_map(svm, svm->nested.vmcb_msrpm, &page); if (!nested_msrpm) return false; @@ -1734,7 +1732,7 @@ 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(page); return true; } @@ -1744,8 +1742,9 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm) struct vmcb *nested_vmcb; struct vmcb *hsave = svm->nested.hsave; struct vmcb *vmcb = svm->vmcb; + struct page *page; - nested_vmcb = nested_svm_map(svm, svm->vmcb->save.rax, KM_USER0); + nested_vmcb = nested_svm_map(svm, svm->vmcb->save.rax, &page); if (!nested_vmcb) return false; @@ -1857,7 +1856,7 @@ 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(page); enable_gif(svm); @@ -1883,6 +1882,7 @@ static void nested_svm_vmloadsave(struct vmcb *from_vmcb, struct vmcb *to_vmcb) static int vmload_interception(struct vcpu_svm *svm) { struct vmcb *nested_vmcb; + struct page *page; if (nested_svm_check_permissions(svm)) return 1; @@ -1890,12 +1890,12 @@ 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, &page); if (!nested_vmcb) return 1; nested_svm_vmloadsave(nested_vmcb, svm->vmcb); - nested_svm_unmap(nested_vmcb, KM_USER0); + nested_svm_unmap(page); return 1; } @@ -1903,6 +1903,7 @@ static int vmload_interception(struct vcpu_svm *svm) static int vmsave_interception(struct vcpu_svm *svm) { struct vmcb *nested_vmcb; + struct page *page; if (nested_svm_check_permissions(svm)) return 1; @@ -1910,12 +1911,12 @@ 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, &page); if (!nested_vmcb) return 1; nested_svm_vmloadsave(svm->vmcb, nested_vmcb); - nested_svm_unmap(nested_vmcb, KM_USER0); + nested_svm_unmap(page); return 1; } -- 2.20.1