diff options
Diffstat (limited to 'arch/arm/kvm/emulate.c')
| -rw-r--r-- | arch/arm/kvm/emulate.c | 75 |
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; |