diff options
author | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-06-15 16:14:34 -0700 |
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committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-06-15 16:14:34 -0700 |
commit | 3ea88d6738ebda95e05ada0c7b72f224d0a36953 (patch) | |
tree | b087d4d9d978556d6f673d8ce93489ef2b0da9ad | |
parent | 4ff4275b24fdcca189b33f9a73fe7abef1dc84bc (diff) | |
parent | 7702fd1f6fea57921f2e643d27a23a2d0394499c (diff) |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm:
KVM: Prevent guest fpu state from leaking into the host
-rw-r--r-- | drivers/kvm/kvm.h | 3 | ||||
-rw-r--r-- | drivers/kvm/kvm_main.c | 22 | ||||
-rw-r--r-- | drivers/kvm/vmx.c | 12 |
3 files changed, 28 insertions, 9 deletions
diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h index 1c040d80c64..152312c1faf 100644 --- a/drivers/kvm/kvm.h +++ b/drivers/kvm/kvm.h @@ -304,6 +304,7 @@ struct kvm_vcpu { char *host_fx_image; char *guest_fx_image; int fpu_active; + int guest_fpu_loaded; int mmio_needed; int mmio_read_completed; @@ -508,6 +509,8 @@ void fx_init(struct kvm_vcpu *vcpu); void load_msrs(struct vmx_msr_entry *e, int n); void save_msrs(struct vmx_msr_entry *e, int n); void kvm_resched(struct kvm_vcpu *vcpu); +void kvm_load_guest_fpu(struct kvm_vcpu *vcpu); +void kvm_put_guest_fpu(struct kvm_vcpu *vcpu); int kvm_read_guest(struct kvm_vcpu *vcpu, gva_t addr, diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c index da985b31b17..8f1f07adb04 100644 --- a/drivers/kvm/kvm_main.c +++ b/drivers/kvm/kvm_main.c @@ -253,6 +253,28 @@ int kvm_write_guest(struct kvm_vcpu *vcpu, gva_t addr, unsigned long size, } EXPORT_SYMBOL_GPL(kvm_write_guest); +void kvm_load_guest_fpu(struct kvm_vcpu *vcpu) +{ + if (!vcpu->fpu_active || vcpu->guest_fpu_loaded) + return; + + vcpu->guest_fpu_loaded = 1; + fx_save(vcpu->host_fx_image); + fx_restore(vcpu->guest_fx_image); +} +EXPORT_SYMBOL_GPL(kvm_load_guest_fpu); + +void kvm_put_guest_fpu(struct kvm_vcpu *vcpu) +{ + if (!vcpu->guest_fpu_loaded) + return; + + vcpu->guest_fpu_loaded = 0; + fx_save(vcpu->guest_fx_image); + fx_restore(vcpu->host_fx_image); +} +EXPORT_SYMBOL_GPL(kvm_put_guest_fpu); + /* * Switches to specified vcpu, until a matching vcpu_put() */ diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c index 184238e2ece..c1ac106ace8 100644 --- a/drivers/kvm/vmx.c +++ b/drivers/kvm/vmx.c @@ -280,6 +280,7 @@ static void vmx_vcpu_load(struct kvm_vcpu *vcpu) static void vmx_vcpu_put(struct kvm_vcpu *vcpu) { + kvm_put_guest_fpu(vcpu); put_cpu(); } @@ -1847,10 +1848,8 @@ again: if (vcpu->guest_debug.enabled) kvm_guest_debug_pre(vcpu); - if (vcpu->fpu_active) { - fx_save(vcpu->host_fx_image); - fx_restore(vcpu->guest_fx_image); - } + kvm_load_guest_fpu(vcpu); + /* * Loading guest fpu may have cleared host cr0.ts */ @@ -2012,11 +2011,6 @@ again: } #endif - if (vcpu->fpu_active) { - fx_save(vcpu->guest_fx_image); - fx_restore(vcpu->host_fx_image); - } - vcpu->interrupt_window_open = (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) & 3) == 0; asm ("mov %0, %%ds; mov %0, %%es" : : "r"(__USER_DS)); |