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Diffstat (limited to 'arch/arm/kvm/emulate.c')
-rw-r--r--arch/arm/kvm/emulate.c75
1 files changed, 52 insertions, 23 deletions
diff --git a/arch/arm/kvm/emulate.c b/arch/arm/kvm/emulate.c
index d61450ac6665..bdede9e7da51 100644
--- a/arch/arm/kvm/emulate.c
+++ b/arch/arm/kvm/emulate.c
@@ -20,6 +20,7 @@
#include <linux/kvm_host.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_emulate.h>
+#include <asm/opcodes.h>
#include <trace/events/kvm.h>
#include "trace.h"
@@ -109,10 +110,10 @@ static const unsigned long vcpu_reg_offsets[VCPU_NR_MODES][15] = {
* Return a pointer to the register number valid in the current mode of
* the virtual CPU.
*/
-u32 *vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num)
+unsigned long *vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num)
{
- u32 *reg_array = (u32 *)&vcpu->arch.regs;
- u32 mode = *vcpu_cpsr(vcpu) & MODE_MASK;
+ unsigned long *reg_array = (unsigned long *)&vcpu->arch.regs;
+ unsigned long mode = *vcpu_cpsr(vcpu) & MODE_MASK;
switch (mode) {
case USR_MODE...SVC_MODE:
@@ -141,9 +142,9 @@ u32 *vcpu_reg(struct kvm_vcpu *vcpu, u8 reg_num)
/*
* Return the SPSR for the current mode of the virtual CPU.
*/
-u32 *vcpu_spsr(struct kvm_vcpu *vcpu)
+unsigned long *vcpu_spsr(struct kvm_vcpu *vcpu)
{
- u32 mode = *vcpu_cpsr(vcpu) & MODE_MASK;
+ unsigned long mode = *vcpu_cpsr(vcpu) & MODE_MASK;
switch (mode) {
case SVC_MODE:
return &vcpu->arch.regs.KVM_ARM_SVC_spsr;
@@ -160,20 +161,48 @@ u32 *vcpu_spsr(struct kvm_vcpu *vcpu)
}
}
-/**
- * kvm_handle_wfi - handle a wait-for-interrupts instruction executed by a guest
- * @vcpu: the vcpu pointer
- * @run: the kvm_run structure pointer
- *
- * Simply sets the wait_for_interrupts flag on the vcpu structure, which will
- * halt execution of world-switches and schedule other host processes until
- * there is an incoming IRQ or FIQ to the VM.
+/*
+ * A conditional instruction is allowed to trap, even though it
+ * wouldn't be executed. So let's re-implement the hardware, in
+ * software!
*/
-int kvm_handle_wfi(struct kvm_vcpu *vcpu, struct kvm_run *run)
+bool kvm_condition_valid(struct kvm_vcpu *vcpu)
{
- trace_kvm_wfi(*vcpu_pc(vcpu));
- kvm_vcpu_block(vcpu);
- return 1;
+ unsigned long cpsr, cond, insn;
+
+ /*
+ * Exception Code 0 can only happen if we set HCR.TGE to 1, to
+ * catch undefined instructions, and then we won't get past
+ * the arm_exit_handlers test anyway.
+ */
+ BUG_ON(!kvm_vcpu_trap_get_class(vcpu));
+
+ /* Top two bits non-zero? Unconditional. */
+ if (kvm_vcpu_get_hsr(vcpu) >> 30)
+ return true;
+
+ cpsr = *vcpu_cpsr(vcpu);
+
+ /* Is condition field valid? */
+ if ((kvm_vcpu_get_hsr(vcpu) & HSR_CV) >> HSR_CV_SHIFT)
+ cond = (kvm_vcpu_get_hsr(vcpu) & HSR_COND) >> HSR_COND_SHIFT;
+ else {
+ /* This can happen in Thumb mode: examine IT state. */
+ unsigned long it;
+
+ it = ((cpsr >> 8) & 0xFC) | ((cpsr >> 25) & 0x3);
+
+ /* it == 0 => unconditional. */
+ if (it == 0)
+ return true;
+
+ /* The cond for this insn works out as the top 4 bits. */
+ cond = (it >> 4);
+ }
+
+ /* Shift makes it look like an ARM-mode instruction */
+ insn = cond << 28;
+ return arm_check_condition(insn, cpsr) != ARM_OPCODE_CONDTEST_FAIL;
}
/**
@@ -257,9 +286,9 @@ static u32 exc_vector_base(struct kvm_vcpu *vcpu)
*/
void kvm_inject_undefined(struct kvm_vcpu *vcpu)
{
- u32 new_lr_value;
- u32 new_spsr_value;
- u32 cpsr = *vcpu_cpsr(vcpu);
+ unsigned long new_lr_value;
+ unsigned long new_spsr_value;
+ unsigned long cpsr = *vcpu_cpsr(vcpu);
u32 sctlr = vcpu->arch.cp15[c1_SCTLR];
bool is_thumb = (cpsr & PSR_T_BIT);
u32 vect_offset = 4;
@@ -291,9 +320,9 @@ void kvm_inject_undefined(struct kvm_vcpu *vcpu)
*/
static void inject_abt(struct kvm_vcpu *vcpu, bool is_pabt, unsigned long addr)
{
- u32 new_lr_value;
- u32 new_spsr_value;
- u32 cpsr = *vcpu_cpsr(vcpu);
+ unsigned long new_lr_value;
+ unsigned long new_spsr_value;
+ unsigned long cpsr = *vcpu_cpsr(vcpu);
u32 sctlr = vcpu->arch.cp15[c1_SCTLR];
bool is_thumb = (cpsr & PSR_T_BIT);
u32 vect_offset;