On 03/09/2010 04:09 PM, Gleb Natapov wrote:
in/out emulation is broken now. The breakage is different depending
on where IO device resides. If it is in userspace emulator reports
emulation failure since it incorrectly interprets kvm_emulate_pio()
return value. If IO device is in the kernel emulation of 'in' will do
nothing since kvm_emulate_pio() stores result directly into vcpu
registers, so emulator will overwrite result of emulation during
commit of shadowed register.
index def4877..315e8a8 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1488,29 +1488,9 @@ static int shutdown_interception(struct vcpu_svm *svm)
static int io_interception(struct vcpu_svm *svm)
{
- u32 io_info = svm->vmcb->control.exit_info_1; /* address size bug? */
- int size, in, string;
- unsigned port;
-
++svm->vcpu.stat.io_exits;
- svm->next_rip = svm->vmcb->control.exit_info_2;
-
- string = (io_info& SVM_IOIO_STR_MASK) != 0;
-
- if (string) {
- if (emulate_instruction(&svm->vcpu,
- 0, 0, 0) == EMULATE_DO_MMIO)
- return 0;
- return 1;
- }
-
- in = (io_info& SVM_IOIO_TYPE_MASK) != 0;
- port = io_info>> 16;
- size = (io_info& SVM_IOIO_SIZE_MASK)>> SVM_IOIO_SIZE_SHIFT;
-
- skip_emulated_instruction(&svm->vcpu);
- return kvm_emulate_pio(&svm->vcpu, in, size, port);
+ return !(emulate_instruction(&svm->vcpu, 0, 0, 0) == EMULATE_DO_MMIO);
}
We don't want to enter the emulator for non-string in/out. Leftover
test code?
static int nmi_interception(struct vcpu_svm *svm)
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index ae3217d..7f33d8e 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2974,26 +2974,9 @@ static int handle_triple_fault(struct kvm_vcpu *vcpu)
static int handle_io(struct kvm_vcpu *vcpu)
{
- unsigned long exit_qualification;
- int size, in, string;
- unsigned port;
-
++vcpu->stat.io_exits;
- exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
- string = (exit_qualification& 16) != 0;
- if (string) {
- if (emulate_instruction(vcpu, 0, 0, 0) == EMULATE_DO_MMIO)
- return 0;
- return 1;
- }
-
- size = (exit_qualification& 7) + 1;
- in = (exit_qualification& 8) != 0;
- port = exit_qualification>> 16;
-
- skip_emulated_instruction(vcpu);
- return kvm_emulate_pio(vcpu, in, size, port);
+ return !(emulate_instruction(vcpu, 0, 0, 0) == EMULATE_DO_MMIO);
}
Ditto.
--
error compiling committee.c: too many arguments to function
--
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