On Mon, Feb 18, 2013 at 11:21:16AM +0100, Jan Kiszka wrote: > This prevents trapping L2 I/O exits if L1 has neither unconditional nor > bitmap-based exiting enabled. Furthermore, it implements I/O bitmap > handling. > > Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx> Reviewed-by: Gleb Natapov <gleb@xxxxxxxxxx> > --- > > Changes in v6: > - drop the bogus check of vmx_basix.54 again > - exit unconditionally on I/O address wrap around > > arch/x86/kvm/vmx.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++-- > 1 files changed, 47 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index 6667042..b4ce43c 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -5908,6 +5908,52 @@ static int (*const kvm_vmx_exit_handlers[])(struct kvm_vcpu *vcpu) = { > static const int kvm_vmx_max_exit_handlers = > ARRAY_SIZE(kvm_vmx_exit_handlers); > > +static bool nested_vmx_exit_handled_io(struct kvm_vcpu *vcpu, > + struct vmcs12 *vmcs12) > +{ > + unsigned long exit_qualification; > + gpa_t bitmap, last_bitmap; > + unsigned int port; > + int size; > + u8 b; > + > + if (nested_cpu_has(vmcs12, CPU_BASED_UNCOND_IO_EXITING)) > + return 1; > + > + if (!nested_cpu_has(vmcs12, CPU_BASED_USE_IO_BITMAPS)) > + return 0; > + > + exit_qualification = vmcs_readl(EXIT_QUALIFICATION); > + > + port = exit_qualification >> 16; > + size = (exit_qualification & 7) + 1; > + > + last_bitmap = (gpa_t)-1; > + b = -1; > + > + while (size > 0) { > + if (port < 0x8000) > + bitmap = vmcs12->io_bitmap_a; > + else if (port < 0x10000) > + bitmap = vmcs12->io_bitmap_b; > + else > + return 1; > + bitmap += (port & 0x7fff) / 8; > + > + if (last_bitmap != bitmap) > + if (kvm_read_guest(vcpu->kvm, bitmap, &b, 1)) > + return 1; > + if (b & (1 << (port & 7))) > + return 1; > + > + port++; > + size--; > + last_bitmap = bitmap; > + } > + > + return 0; > +} > + > /* > * Return 1 if we should exit from L2 to L1 to handle an MSR access access, > * rather than handle it ourselves in L0. I.e., check whether L1 expressed > @@ -6097,8 +6143,7 @@ static bool nested_vmx_exit_handled(struct kvm_vcpu *vcpu) > case EXIT_REASON_DR_ACCESS: > return nested_cpu_has(vmcs12, CPU_BASED_MOV_DR_EXITING); > case EXIT_REASON_IO_INSTRUCTION: > - /* TODO: support IO bitmaps */ > - return 1; > + return nested_vmx_exit_handled_io(vcpu, vmcs12); > case EXIT_REASON_MSR_READ: > case EXIT_REASON_MSR_WRITE: > return nested_vmx_exit_handled_msr(vcpu, vmcs12, exit_reason); > -- > 1.7.3.4 -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html