KVM: SVM: handle singlestep exception when skipping emulated instructions

kvm_skip_emulated_instruction handles the singlestep debug exception
which is something we almost always want. This commit (specifically
the change in rdmsr_interception) makes the debug.flat KVM unit test
pass on AMD.

Two call sites still call skip_emulated_instruction directly:

* In svm_queue_exception where it's used only for moving the rip forward

* In task_switch_interception which is analogous to handle_task_switch
  in VMX

Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
This commit is contained in:
Ladi Prosek 2017-06-22 09:05:26 +02:00 committed by Radim Krčmář
parent fb5307298e
commit b742c1e6e7

View File

@ -2267,7 +2267,7 @@ static int io_interception(struct vcpu_svm *svm)
{
struct kvm_vcpu *vcpu = &svm->vcpu;
u32 io_info = svm->vmcb->control.exit_info_1; /* address size bug? */
int size, in, string;
int size, in, string, ret;
unsigned port;
++svm->vcpu.stat.io_exits;
@ -2279,10 +2279,16 @@ static int io_interception(struct vcpu_svm *svm)
port = io_info >> 16;
size = (io_info & SVM_IOIO_SIZE_MASK) >> SVM_IOIO_SIZE_SHIFT;
svm->next_rip = svm->vmcb->control.exit_info_2;
skip_emulated_instruction(&svm->vcpu);
ret = kvm_skip_emulated_instruction(&svm->vcpu);
return in ? kvm_fast_pio_in(vcpu, size, port)
: kvm_fast_pio_out(vcpu, size, port);
/*
* TODO: we might be squashing a KVM_GUESTDBG_SINGLESTEP-triggered
* KVM_EXIT_DEBUG here.
*/
if (in)
return kvm_fast_pio_in(vcpu, size, port) && ret;
else
return kvm_fast_pio_out(vcpu, size, port) && ret;
}
static int nmi_interception(struct vcpu_svm *svm)
@ -3055,6 +3061,7 @@ static int vmload_interception(struct vcpu_svm *svm)
{
struct vmcb *nested_vmcb;
struct page *page;
int ret;
if (nested_svm_check_permissions(svm))
return 1;
@ -3064,18 +3071,19 @@ static int vmload_interception(struct vcpu_svm *svm)
return 1;
svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
skip_emulated_instruction(&svm->vcpu);
ret = kvm_skip_emulated_instruction(&svm->vcpu);
nested_svm_vmloadsave(nested_vmcb, svm->vmcb);
nested_svm_unmap(page);
return 1;
return ret;
}
static int vmsave_interception(struct vcpu_svm *svm)
{
struct vmcb *nested_vmcb;
struct page *page;
int ret;
if (nested_svm_check_permissions(svm))
return 1;
@ -3085,12 +3093,12 @@ static int vmsave_interception(struct vcpu_svm *svm)
return 1;
svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
skip_emulated_instruction(&svm->vcpu);
ret = kvm_skip_emulated_instruction(&svm->vcpu);
nested_svm_vmloadsave(svm->vmcb, nested_vmcb);
nested_svm_unmap(page);
return 1;
return ret;
}
static int vmrun_interception(struct vcpu_svm *svm)
@ -3123,25 +3131,29 @@ static int vmrun_interception(struct vcpu_svm *svm)
static int stgi_interception(struct vcpu_svm *svm)
{
int ret;
if (nested_svm_check_permissions(svm))
return 1;
svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
skip_emulated_instruction(&svm->vcpu);
ret = kvm_skip_emulated_instruction(&svm->vcpu);
kvm_make_request(KVM_REQ_EVENT, &svm->vcpu);
enable_gif(svm);
return 1;
return ret;
}
static int clgi_interception(struct vcpu_svm *svm)
{
int ret;
if (nested_svm_check_permissions(svm))
return 1;
svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
skip_emulated_instruction(&svm->vcpu);
ret = kvm_skip_emulated_instruction(&svm->vcpu);
disable_gif(svm);
@ -3152,7 +3164,7 @@ static int clgi_interception(struct vcpu_svm *svm)
mark_dirty(svm->vmcb, VMCB_INTR);
}
return 1;
return ret;
}
static int invlpga_interception(struct vcpu_svm *svm)
@ -3166,8 +3178,7 @@ static int invlpga_interception(struct vcpu_svm *svm)
kvm_mmu_invlpg(vcpu, kvm_register_read(&svm->vcpu, VCPU_REGS_RAX));
svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
skip_emulated_instruction(&svm->vcpu);
return 1;
return kvm_skip_emulated_instruction(&svm->vcpu);
}
static int skinit_interception(struct vcpu_svm *svm)
@ -3190,7 +3201,7 @@ static int xsetbv_interception(struct vcpu_svm *svm)
if (kvm_set_xcr(&svm->vcpu, index, new_bv) == 0) {
svm->next_rip = kvm_rip_read(&svm->vcpu) + 3;
skip_emulated_instruction(&svm->vcpu);
return kvm_skip_emulated_instruction(&svm->vcpu);
}
return 1;
@ -3286,8 +3297,7 @@ static int invlpg_interception(struct vcpu_svm *svm)
return emulate_instruction(&svm->vcpu, 0) == EMULATE_DONE;
kvm_mmu_invlpg(&svm->vcpu, svm->vmcb->control.exit_info_1);
skip_emulated_instruction(&svm->vcpu);
return 1;
return kvm_skip_emulated_instruction(&svm->vcpu);
}
static int emulate_on_interception(struct vcpu_svm *svm)
@ -3437,9 +3447,7 @@ static int dr_interception(struct vcpu_svm *svm)
kvm_register_write(&svm->vcpu, reg, val);
}
skip_emulated_instruction(&svm->vcpu);
return 1;
return kvm_skip_emulated_instruction(&svm->vcpu);
}
static int cr8_write_interception(struct vcpu_svm *svm)
@ -3562,6 +3570,7 @@ static int rdmsr_interception(struct vcpu_svm *svm)
if (svm_get_msr(&svm->vcpu, &msr_info)) {
trace_kvm_msr_read_ex(ecx);
kvm_inject_gp(&svm->vcpu, 0);
return 1;
} else {
trace_kvm_msr_read(ecx, msr_info.data);
@ -3570,9 +3579,8 @@ static int rdmsr_interception(struct vcpu_svm *svm)
kvm_register_write(&svm->vcpu, VCPU_REGS_RDX,
msr_info.data >> 32);
svm->next_rip = kvm_rip_read(&svm->vcpu) + 2;
skip_emulated_instruction(&svm->vcpu);
return kvm_skip_emulated_instruction(&svm->vcpu);
}
return 1;
}
static int svm_set_vm_cr(struct kvm_vcpu *vcpu, u64 data)
@ -3698,11 +3706,11 @@ static int wrmsr_interception(struct vcpu_svm *svm)
if (kvm_set_msr(&svm->vcpu, &msr)) {
trace_kvm_msr_write_ex(ecx, data);
kvm_inject_gp(&svm->vcpu, 0);
return 1;
} else {
trace_kvm_msr_write(ecx, data);
skip_emulated_instruction(&svm->vcpu);
return kvm_skip_emulated_instruction(&svm->vcpu);
}
return 1;
}
static int msr_interception(struct vcpu_svm *svm)
@ -3731,8 +3739,7 @@ static int pause_interception(struct vcpu_svm *svm)
static int nop_interception(struct vcpu_svm *svm)
{
skip_emulated_instruction(&(svm->vcpu));
return 1;
return kvm_skip_emulated_instruction(&(svm->vcpu));
}
static int monitor_interception(struct vcpu_svm *svm)