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-rw-r--r--arch/arm64/kvm/hyp/switch.c21
-rw-r--r--arch/arm64/kvm/hyp/sysreg-sr.c5
-rw-r--r--arch/arm64/kvm/reset.c50
-rw-r--r--arch/arm64/kvm/sys_regs.c50
4 files changed, 106 insertions, 20 deletions
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index b0b1478094b4..3563fe655cd5 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -22,7 +22,9 @@
#include <kvm/arm_psci.h>
+#include <asm/arch_gicv3.h>
#include <asm/cpufeature.h>
+#include <asm/kprobes.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_host.h>
@@ -107,6 +109,7 @@ static void activate_traps_vhe(struct kvm_vcpu *vcpu)
write_sysreg(kvm_get_hyp_vector(), vbar_el1);
}
+NOKPROBE_SYMBOL(activate_traps_vhe);
static void __hyp_text __activate_traps_nvhe(struct kvm_vcpu *vcpu)
{
@@ -154,6 +157,7 @@ static void deactivate_traps_vhe(void)
write_sysreg(CPACR_EL1_DEFAULT, cpacr_el1);
write_sysreg(vectors, vbar_el1);
}
+NOKPROBE_SYMBOL(deactivate_traps_vhe);
static void __hyp_text __deactivate_traps_nvhe(void)
{
@@ -513,6 +517,7 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
return exit_code;
}
+NOKPROBE_SYMBOL(kvm_vcpu_run_vhe);
/* Switch to the guest for legacy non-VHE systems */
int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
@@ -521,6 +526,17 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
struct kvm_cpu_context *guest_ctxt;
u64 exit_code;
+ /*
+ * Having IRQs masked via PMR when entering the guest means the GIC
+ * will not signal the CPU of interrupts of lower priority, and the
+ * only way to get out will be via guest exceptions.
+ * Naturally, we want to avoid this.
+ */
+ if (system_uses_irq_prio_masking()) {
+ gic_write_pmr(GIC_PRIO_IRQON);
+ dsb(sy);
+ }
+
vcpu = kern_hyp_va(vcpu);
host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context);
@@ -573,6 +589,10 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
*/
__debug_switch_to_host(vcpu);
+ /* Returning to host will clear PSR.I, remask PMR if needed */
+ if (system_uses_irq_prio_masking())
+ gic_write_pmr(GIC_PRIO_IRQOFF);
+
return exit_code;
}
@@ -620,6 +640,7 @@ static void __hyp_call_panic_vhe(u64 spsr, u64 elr, u64 par,
read_sysreg_el2(esr), read_sysreg_el2(far),
read_sysreg(hpfar_el2), par, vcpu);
}
+NOKPROBE_SYMBOL(__hyp_call_panic_vhe);
void __hyp_text __noreturn hyp_panic(struct kvm_cpu_context *host_ctxt)
{
diff --git a/arch/arm64/kvm/hyp/sysreg-sr.c b/arch/arm64/kvm/hyp/sysreg-sr.c
index 68d6f7c3b237..b426e2cf973c 100644
--- a/arch/arm64/kvm/hyp/sysreg-sr.c
+++ b/arch/arm64/kvm/hyp/sysreg-sr.c
@@ -18,6 +18,7 @@
#include <linux/compiler.h>
#include <linux/kvm_host.h>
+#include <asm/kprobes.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_hyp.h>
@@ -98,12 +99,14 @@ void sysreg_save_host_state_vhe(struct kvm_cpu_context *ctxt)
{
__sysreg_save_common_state(ctxt);
}
+NOKPROBE_SYMBOL(sysreg_save_host_state_vhe);
void sysreg_save_guest_state_vhe(struct kvm_cpu_context *ctxt)
{
__sysreg_save_common_state(ctxt);
__sysreg_save_el2_return_state(ctxt);
}
+NOKPROBE_SYMBOL(sysreg_save_guest_state_vhe);
static void __hyp_text __sysreg_restore_common_state(struct kvm_cpu_context *ctxt)
{
@@ -188,12 +191,14 @@ void sysreg_restore_host_state_vhe(struct kvm_cpu_context *ctxt)
{
__sysreg_restore_common_state(ctxt);
}
+NOKPROBE_SYMBOL(sysreg_restore_host_state_vhe);
void sysreg_restore_guest_state_vhe(struct kvm_cpu_context *ctxt)
{
__sysreg_restore_common_state(ctxt);
__sysreg_restore_el2_return_state(ctxt);
}
+NOKPROBE_SYMBOL(sysreg_restore_guest_state_vhe);
void __hyp_text __sysreg32_save_state(struct kvm_vcpu *vcpu)
{
diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c
index b72a3dd56204..f16a5f8ff2b4 100644
--- a/arch/arm64/kvm/reset.c
+++ b/arch/arm64/kvm/reset.c
@@ -32,6 +32,7 @@
#include <asm/kvm_arm.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_coproc.h>
+#include <asm/kvm_emulate.h>
#include <asm/kvm_mmu.h>
/* Maximum phys_shift supported for any VM on this host */
@@ -105,16 +106,33 @@ int kvm_arch_vm_ioctl_check_extension(struct kvm *kvm, long ext)
* This function finds the right table above and sets the registers on
* the virtual CPU struct to their architecturally defined reset
* values.
+ *
+ * Note: This function can be called from two paths: The KVM_ARM_VCPU_INIT
+ * ioctl or as part of handling a request issued by another VCPU in the PSCI
+ * handling code. In the first case, the VCPU will not be loaded, and in the
+ * second case the VCPU will be loaded. Because this function operates purely
+ * on the memory-backed valus of system registers, we want to do a full put if
+ * we were loaded (handling a request) and load the values back at the end of
+ * the function. Otherwise we leave the state alone. In both cases, we
+ * disable preemption around the vcpu reset as we would otherwise race with
+ * preempt notifiers which also call put/load.
*/
int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
{
const struct kvm_regs *cpu_reset;
+ int ret = -EINVAL;
+ bool loaded;
+
+ preempt_disable();
+ loaded = (vcpu->cpu != -1);
+ if (loaded)
+ kvm_arch_vcpu_put(vcpu);
switch (vcpu->arch.target) {
default:
if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features)) {
if (!cpu_has_32bit_el1())
- return -EINVAL;
+ goto out;
cpu_reset = &default_regs_reset32;
} else {
cpu_reset = &default_regs_reset;
@@ -129,6 +147,29 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
/* Reset system registers */
kvm_reset_sys_regs(vcpu);
+ /*
+ * Additional reset state handling that PSCI may have imposed on us.
+ * Must be done after all the sys_reg reset.
+ */
+ if (vcpu->arch.reset_state.reset) {
+ unsigned long target_pc = vcpu->arch.reset_state.pc;
+
+ /* Gracefully handle Thumb2 entry point */
+ if (vcpu_mode_is_32bit(vcpu) && (target_pc & 1)) {
+ target_pc &= ~1UL;
+ vcpu_set_thumb(vcpu);
+ }
+
+ /* Propagate caller endianness */
+ if (vcpu->arch.reset_state.be)
+ kvm_vcpu_set_be(vcpu);
+
+ *vcpu_pc(vcpu) = target_pc;
+ vcpu_set_reg(vcpu, 0, vcpu->arch.reset_state.r0);
+
+ vcpu->arch.reset_state.reset = false;
+ }
+
/* Reset PMU */
kvm_pmu_vcpu_reset(vcpu);
@@ -137,7 +178,12 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
vcpu->arch.workaround_flags |= VCPU_WORKAROUND_2_FLAG;
/* Reset timer */
- return kvm_timer_vcpu_reset(vcpu);
+ ret = kvm_timer_vcpu_reset(vcpu);
+out:
+ if (loaded)
+ kvm_arch_vcpu_load(vcpu, smp_processor_id());
+ preempt_enable();
+ return ret;
}
void kvm_set_ipa_limit(void)
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index e3e37228ae4e..c936aa40c3f4 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -314,12 +314,29 @@ static bool trap_raz_wi(struct kvm_vcpu *vcpu,
return read_zero(vcpu, p);
}
-static bool trap_undef(struct kvm_vcpu *vcpu,
- struct sys_reg_params *p,
- const struct sys_reg_desc *r)
+/*
+ * ARMv8.1 mandates at least a trivial LORegion implementation, where all the
+ * RW registers are RES0 (which we can implement as RAZ/WI). On an ARMv8.0
+ * system, these registers should UNDEF. LORID_EL1 being a RO register, we
+ * treat it separately.
+ */
+static bool trap_loregion(struct kvm_vcpu *vcpu,
+ struct sys_reg_params *p,
+ const struct sys_reg_desc *r)
{
- kvm_inject_undefined(vcpu);
- return false;
+ u64 val = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
+ u32 sr = sys_reg((u32)r->Op0, (u32)r->Op1,
+ (u32)r->CRn, (u32)r->CRm, (u32)r->Op2);
+
+ if (!(val & (0xfUL << ID_AA64MMFR1_LOR_SHIFT))) {
+ kvm_inject_undefined(vcpu);
+ return false;
+ }
+
+ if (p->is_write && sr == SYS_LORID_EL1)
+ return write_to_read_only(vcpu, p, r);
+
+ return trap_raz_wi(vcpu, p, r);
}
static bool trap_oslsr_el1(struct kvm_vcpu *vcpu,
@@ -1048,11 +1065,6 @@ static u64 read_id_reg(struct sys_reg_desc const *r, bool raz)
if (val & ptrauth_mask)
kvm_debug("ptrauth unsupported for guests, suppressing\n");
val &= ~ptrauth_mask;
- } else if (id == SYS_ID_AA64MMFR1_EL1) {
- if (val & (0xfUL << ID_AA64MMFR1_LOR_SHIFT))
- kvm_debug("LORegions unsupported for guests, suppressing\n");
-
- val &= ~(0xfUL << ID_AA64MMFR1_LOR_SHIFT);
}
return val;
@@ -1338,11 +1350,11 @@ static const struct sys_reg_desc sys_reg_descs[] = {
{ SYS_DESC(SYS_MAIR_EL1), access_vm_reg, reset_unknown, MAIR_EL1 },
{ SYS_DESC(SYS_AMAIR_EL1), access_vm_reg, reset_amair_el1, AMAIR_EL1 },
- { SYS_DESC(SYS_LORSA_EL1), trap_undef },
- { SYS_DESC(SYS_LOREA_EL1), trap_undef },
- { SYS_DESC(SYS_LORN_EL1), trap_undef },
- { SYS_DESC(SYS_LORC_EL1), trap_undef },
- { SYS_DESC(SYS_LORID_EL1), trap_undef },
+ { SYS_DESC(SYS_LORSA_EL1), trap_loregion },
+ { SYS_DESC(SYS_LOREA_EL1), trap_loregion },
+ { SYS_DESC(SYS_LORN_EL1), trap_loregion },
+ { SYS_DESC(SYS_LORC_EL1), trap_loregion },
+ { SYS_DESC(SYS_LORID_EL1), trap_loregion },
{ SYS_DESC(SYS_VBAR_EL1), NULL, reset_val, VBAR_EL1, 0 },
{ SYS_DESC(SYS_DISR_EL1), NULL, reset_val, DISR_EL1, 0 },
@@ -2596,7 +2608,9 @@ void kvm_reset_sys_regs(struct kvm_vcpu *vcpu)
table = get_target_table(vcpu->arch.target, true, &num);
reset_sys_reg_descs(vcpu, table, num);
- for (num = 1; num < NR_SYS_REGS; num++)
- if (__vcpu_sys_reg(vcpu, num) == 0x4242424242424242)
- panic("Didn't reset __vcpu_sys_reg(%zi)", num);
+ for (num = 1; num < NR_SYS_REGS; num++) {
+ if (WARN(__vcpu_sys_reg(vcpu, num) == 0x4242424242424242,
+ "Didn't reset __vcpu_sys_reg(%zi)\n", num))
+ break;
+ }
}
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