accessible from EL2 and above are trapped to EL2. In these cases,
ESR_EL2.EC will be set to 0x18.
Rework the system instruction emulation framework to handle potentially
all system instruction traps other than MSR/MRS instructions. Those
system instructions would be AT and TLBI instructions controlled by
HCR_EL2.NV, AT, and TTLB bits.
Signed-off-by: Jintack Lim <jintack.lim@xxxxxxxxxx>
[maz: squashed two patches together, redispatched various bits around]
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
arch/arm64/include/asm/kvm_host.h | 4 +--
arch/arm64/kvm/handle_exit.c | 2 +-
arch/arm64/kvm/sys_regs.c | 48 +++++++++++++++++++++++++------
3 files changed, 42 insertions(+), 12 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 00c3366129b8..35f3d7939484 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -411,7 +411,7 @@ struct kvm_vcpu_arch {
/*
* Guest registers we preserve during guest debugging.
*
- * These shadow registers are updated by the kvm_handle_sys_reg
+ * These shadow registers are updated by the kvm_handle_sys
* trap handler if the guest accesses or updates them while we
* are using guest debug.
*/
@@ -729,7 +729,7 @@ int kvm_handle_cp14_32(struct kvm_vcpu *vcpu);
int kvm_handle_cp14_64(struct kvm_vcpu *vcpu);
int kvm_handle_cp15_32(struct kvm_vcpu *vcpu);
int kvm_handle_cp15_64(struct kvm_vcpu *vcpu);
-int kvm_handle_sys_reg(struct kvm_vcpu *vcpu);
+int kvm_handle_sys(struct kvm_vcpu *vcpu);
void kvm_reset_sys_regs(struct kvm_vcpu *vcpu);
diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
index 6ff709c124d0..8b3b758e674e 100644
--- a/arch/arm64/kvm/handle_exit.c
+++ b/arch/arm64/kvm/handle_exit.c
@@ -234,7 +234,7 @@ static exit_handle_fn arm_exit_handlers[] = {
[ESR_ELx_EC_SMC32] = handle_smc,
[ESR_ELx_EC_HVC64] = handle_hvc,
[ESR_ELx_EC_SMC64] = handle_smc,
- [ESR_ELx_EC_SYS64] = kvm_handle_sys_reg,
+ [ESR_ELx_EC_SYS64] = kvm_handle_sys,
[ESR_ELx_EC_SVE] = handle_sve,
[ESR_ELx_EC_ERET] = kvm_handle_eret,
[ESR_ELx_EC_IABT_LOW] = kvm_handle_guest_abort,
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 77f07f960d84..222f8c6f1d7e 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1770,10 +1770,6 @@ static bool access_spsr_el2(struct kvm_vcpu *vcpu,
* more demanding guest...
*/
static const struct sys_reg_desc sys_reg_descs[] = {
- { SYS_DESC(SYS_DC_ISW), access_dcsw },
- { SYS_DESC(SYS_DC_CSW), access_dcsw },
- { SYS_DESC(SYS_DC_CISW), access_dcsw },
-
DBG_BCR_BVR_WCR_WVR_EL1(0),
DBG_BCR_BVR_WCR_WVR_EL1(1),
{ SYS_DESC(SYS_MDCCINT_EL1), trap_debug_regs, reset_val, MDCCINT_EL1, 0 },
@@ -2240,6 +2236,14 @@ static const struct sys_reg_desc sys_reg_descs[] = {
{ SYS_DESC(SYS_SP_EL2), NULL, reset_unknown, SP_EL2 },
};
+#define SYS_INSN_TO_DESC(insn, access_fn, forward_fn) \
+ { SYS_DESC((insn)), (access_fn), NULL, 0, 0, NULL, NULL, (forward_fn) }
+static struct sys_reg_desc sys_insn_descs[] = {
+ { SYS_DESC(SYS_DC_ISW), access_dcsw },
+ { SYS_DESC(SYS_DC_CSW), access_dcsw },
+ { SYS_DESC(SYS_DC_CISW), access_dcsw },
+};
+
static bool trap_dbgdidr(struct kvm_vcpu *vcpu,
struct sys_reg_params *p,
const struct sys_reg_desc *r)
@@ -2794,6 +2798,24 @@ static int emulate_sys_reg(struct kvm_vcpu *vcpu,
return 1;
}
+static int emulate_sys_instr(struct kvm_vcpu *vcpu, struct sys_reg_params *p)
+{
+ const struct sys_reg_desc *r;
+
+ /* Search from the system instruction table. */
+ r = find_reg(p, sys_insn_descs, ARRAY_SIZE(sys_insn_descs));
+
+ if (likely(r)) {
+ perform_access(vcpu, p, r);
+ } else {
+ kvm_err("Unsupported guest sys instruction at: %lx\n",
+ *vcpu_pc(vcpu));
+ print_sys_reg_instr(p);
+ kvm_inject_undefined(vcpu);
+ }
+ return 1;
+}
+
/**
* kvm_reset_sys_regs - sets system registers to reset value
* @vcpu: The VCPU pointer
@@ -2811,10 +2833,11 @@ void kvm_reset_sys_regs(struct kvm_vcpu *vcpu)
}
/**
- * kvm_handle_sys_reg -- handles a mrs/msr trap on a guest sys_reg access
+ * kvm_handle_sys-- handles a system instruction or mrs/msr instruction trap
+ on a guest execution
* @vcpu: The VCPU pointer
*/
-int kvm_handle_sys_reg(struct kvm_vcpu *vcpu)
+int kvm_handle_sys(struct kvm_vcpu *vcpu)
{
struct sys_reg_params params;
unsigned long esr = kvm_vcpu_get_esr(vcpu);
@@ -2826,10 +2849,16 @@ int kvm_handle_sys_reg(struct kvm_vcpu *vcpu)
params = esr_sys64_to_params(esr);
params.regval = vcpu_get_reg(vcpu, Rt);
- ret = emulate_sys_reg(vcpu, ¶ms);
+ if (params.Op0 == 1) {
+ /* System instructions */
+ ret = emulate_sys_instr(vcpu, ¶ms);
+ } else {
+ /* MRS/MSR instructions */
+ ret = emulate_sys_reg(vcpu, ¶ms);
+ if (!params.is_write)
+ vcpu_set_reg(vcpu, Rt, params.regval);
+ }
- if (!params.is_write)
- vcpu_set_reg(vcpu, Rt, params.regval);
return ret;
}
@@ -3245,6 +3274,7 @@ void kvm_sys_reg_table_init(void)
BUG_ON(check_sysreg_table(cp15_regs, ARRAY_SIZE(cp15_regs), true));
BUG_ON(check_sysreg_table(cp15_64_regs, ARRAY_SIZE(cp15_64_regs), true));
BUG_ON(check_sysreg_table(invariant_sys_regs, ARRAY_SIZE(invariant_sys_regs), false));
+ BUG_ON(check_sysreg_table(sys_insn_descs, ARRAY_SIZE(sys_insn_descs), false));
/* We abuse the reset function to overwrite the table itself. */
for (i = 0; i < ARRAY_SIZE(invariant_sys_regs); i++)
