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KVM: Provide x86_emulate_ctxt callback to get current cpl
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Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
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Gleb Natapov authored and Avi Kivity committed May 17, 2010
1 parent 93a152b commit 9c53724
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Showing 3 changed files with 15 additions and 7 deletions.
1 change: 1 addition & 0 deletions arch/x86/include/asm/kvm_emulate.h
Original file line number Diff line number Diff line change
Expand Up @@ -110,6 +110,7 @@ struct x86_emulate_ops {
struct kvm_vcpu *vcpu);
ulong (*get_cr)(int cr, struct kvm_vcpu *vcpu);
void (*set_cr)(int cr, ulong val, struct kvm_vcpu *vcpu);
int (*cpl)(struct kvm_vcpu *vcpu);
};

/* Type, address-of, and value of an instruction's operand. */
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15 changes: 8 additions & 7 deletions arch/x86/kvm/emulate.c
Original file line number Diff line number Diff line change
Expand Up @@ -1257,7 +1257,7 @@ static int emulate_popf(struct x86_emulate_ctxt *ctxt,
int rc;
unsigned long val, change_mask;
int iopl = (ctxt->eflags & X86_EFLAGS_IOPL) >> IOPL_SHIFT;
int cpl = kvm_x86_ops->get_cpl(ctxt->vcpu);
int cpl = ops->cpl(ctxt->vcpu);

rc = emulate_pop(ctxt, ops, &val, len);
if (rc != X86EMUL_CONTINUE)
Expand Down Expand Up @@ -1758,15 +1758,16 @@ emulate_sysexit(struct x86_emulate_ctxt *ctxt)
return X86EMUL_CONTINUE;
}

static bool emulator_bad_iopl(struct x86_emulate_ctxt *ctxt)
static bool emulator_bad_iopl(struct x86_emulate_ctxt *ctxt,
struct x86_emulate_ops *ops)
{
int iopl;
if (ctxt->mode == X86EMUL_MODE_REAL)
return false;
if (ctxt->mode == X86EMUL_MODE_VM86)
return true;
iopl = (ctxt->eflags & X86_EFLAGS_IOPL) >> IOPL_SHIFT;
return kvm_x86_ops->get_cpl(ctxt->vcpu) > iopl;
return ops->cpl(ctxt->vcpu) > iopl;
}

static bool emulator_io_port_access_allowed(struct x86_emulate_ctxt *ctxt,
Expand Down Expand Up @@ -1803,7 +1804,7 @@ static bool emulator_io_permited(struct x86_emulate_ctxt *ctxt,
struct x86_emulate_ops *ops,
u16 port, u16 len)
{
if (emulator_bad_iopl(ctxt))
if (emulator_bad_iopl(ctxt, ops))
if (!emulator_io_port_access_allowed(ctxt, ops, port, len))
return false;
return true;
Expand Down Expand Up @@ -1842,7 +1843,7 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
}

/* Privileged instruction can be executed only in CPL=0 */
if ((c->d & Priv) && kvm_x86_ops->get_cpl(ctxt->vcpu)) {
if ((c->d & Priv) && ops->cpl(ctxt->vcpu)) {
kvm_inject_gp(ctxt->vcpu, 0);
goto done;
}
Expand Down Expand Up @@ -2378,15 +2379,15 @@ x86_emulate_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
c->dst.type = OP_NONE; /* Disable writeback. */
break;
case 0xfa: /* cli */
if (emulator_bad_iopl(ctxt))
if (emulator_bad_iopl(ctxt, ops))
kvm_inject_gp(ctxt->vcpu, 0);
else {
ctxt->eflags &= ~X86_EFLAGS_IF;
c->dst.type = OP_NONE; /* Disable writeback. */
}
break;
case 0xfb: /* sti */
if (emulator_bad_iopl(ctxt))
if (emulator_bad_iopl(ctxt, ops))
kvm_inject_gp(ctxt->vcpu, 0);
else {
toggle_interruptibility(ctxt, KVM_X86_SHADOW_INT_STI);
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6 changes: 6 additions & 0 deletions arch/x86/kvm/x86.c
Original file line number Diff line number Diff line change
Expand Up @@ -3479,6 +3479,11 @@ static void emulator_set_cr(int cr, unsigned long val, struct kvm_vcpu *vcpu)
}
}

static int emulator_get_cpl(struct kvm_vcpu *vcpu)
{
return kvm_x86_ops->get_cpl(vcpu);
}

static struct x86_emulate_ops emulate_ops = {
.read_std = kvm_read_guest_virt_system,
.fetch = kvm_fetch_guest_virt,
Expand All @@ -3487,6 +3492,7 @@ static struct x86_emulate_ops emulate_ops = {
.cmpxchg_emulated = emulator_cmpxchg_emulated,
.get_cr = emulator_get_cr,
.set_cr = emulator_set_cr,
.cpl = emulator_get_cpl,
};

static void cache_all_regs(struct kvm_vcpu *vcpu)
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