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Message-Id: <20200430144831.59194-9-dbrazdil@google.com>
Date: Thu, 30 Apr 2020 15:48:24 +0100
From: David Brazdil <dbrazdil@...gle.com>
To: Catalin Marinas <catalin.marinas@....com>,
James Morse <james.morse@....com>,
Julien Thierry <julien.thierry.kdev@...il.com>,
Marc Zyngier <maz@...nel.org>,
Suzuki K Poulose <suzuki.poulose@....com>,
Will Deacon <will@...nel.org>
Cc: kvmarm@...ts.cs.columbia.edu, linux-arm-kernel@...ts.infradead.org,
linux-kernel@...r.kernel.org, David Brazdil <dbrazdil@...gle.com>
Subject: [PATCH 08/15] arm64: kvm: Split hyp/switch.c to VHE/nVHE
This patch is part of a series which builds KVM's non-VHE hyp code separately
from VHE and the rest of the kernel.
switch.c implements context-switching for KVM, with large parts shared between
VHE/nVHE. These common routines are moved to switch.h, VHE-specific code is
left in switch.c and nVHE-specific code is moved to nvhe/switch.c.
Previously __kvm_vcpu_run needed a different symbol name for VHE/nVHE. This
is cleaned up and the caller in arm.c simplified.
Signed-off-by: David Brazdil <dbrazdil@...gle.com>
---
arch/arm64/include/asm/kvm_asm.h | 4 +-
arch/arm64/include/asm/kvm_host_hypercalls.h | 4 +-
arch/arm64/include/asm/kvm_hyp.h | 5 +
arch/arm64/kernel/image-vars.h | 25 +-
arch/arm64/kvm/arm.c | 6 +-
arch/arm64/kvm/hyp/hyp-entry.S | 2 +
arch/arm64/kvm/hyp/nvhe/Makefile | 2 +-
arch/arm64/kvm/hyp/nvhe/switch.c | 271 ++++++++
arch/arm64/kvm/hyp/switch.c | 688 +------------------
arch/arm64/kvm/hyp/switch.h | 441 ++++++++++++
arch/arm64/kvm/hyp/sysreg-sr.c | 4 +-
11 files changed, 764 insertions(+), 688 deletions(-)
create mode 100644 arch/arm64/kvm/hyp/nvhe/switch.c
create mode 100644 arch/arm64/kvm/hyp/switch.h
diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index cdaf3df8085d..0cb229b9e148 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -86,9 +86,7 @@ extern void __kvm_tlb_flush_local_vmid(struct kvm_vcpu *vcpu);
extern void __kvm_timer_set_cntvoff(u32 cntvoff_low, u32 cntvoff_high);
-extern int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu);
-
-extern int __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu);
+extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
extern u64 __vgic_v3_get_ich_vtr_el2(void);
extern u64 __vgic_v3_read_vmcr(void);
diff --git a/arch/arm64/include/asm/kvm_host_hypercalls.h b/arch/arm64/include/asm/kvm_host_hypercalls.h
index af8ad505d816..cc45930fdc76 100644
--- a/arch/arm64/include/asm/kvm_host_hypercalls.h
+++ b/arch/arm64/include/asm/kvm_host_hypercalls.h
@@ -22,8 +22,8 @@ __KVM_HOST_HCALL(__kvm_tlb_flush_local_vmid)
#define __KVM_HOST_HCALL_TABLE_IDX___kvm_flush_vm_context 4
__KVM_HOST_HCALL(__kvm_flush_vm_context)
-#define __KVM_HOST_HCALL_TABLE_IDX___kvm_vcpu_run_nvhe 5
-__KVM_HOST_HCALL(__kvm_vcpu_run_nvhe)
+#define __KVM_HOST_HCALL_TABLE_IDX___kvm_vcpu_run 5
+__KVM_HOST_HCALL(__kvm_vcpu_run)
#define __KVM_HOST_HCALL_TABLE_IDX___kvm_tlb_flush_vmid 6
__KVM_HOST_HCALL(__kvm_tlb_flush_vmid)
diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h
index fe57f60f06a8..b5895040c16a 100644
--- a/arch/arm64/include/asm/kvm_hyp.h
+++ b/arch/arm64/include/asm/kvm_hyp.h
@@ -82,11 +82,16 @@ void __debug_switch_to_host(struct kvm_vcpu *vcpu);
void __fpsimd_save_state(struct user_fpsimd_state *fp_regs);
void __fpsimd_restore_state(struct user_fpsimd_state *fp_regs);
+#ifndef __HYPERVISOR__
void activate_traps_vhe_load(struct kvm_vcpu *vcpu);
void deactivate_traps_vhe_put(void);
+#endif
u64 __guest_enter(struct kvm_vcpu *vcpu, struct kvm_cpu_context *host_ctxt);
+
+#ifdef __HYPERVISOR__
void __noreturn __hyp_do_panic(unsigned long, ...);
+#endif
/*
* Must be called from hyp code running at EL2 with an updated VTTBR
diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h
index c0a0ec238854..e2282a4304c5 100644
--- a/arch/arm64/kernel/image-vars.h
+++ b/arch/arm64/kernel/image-vars.h
@@ -61,18 +61,34 @@ __efistub__ctype = _ctype;
* memory mappings.
*/
+__hyp_text___debug_switch_to_guest = __debug_switch_to_guest;
+__hyp_text___debug_switch_to_host = __debug_switch_to_host;
+__hyp_text___fpsimd_restore_state = __fpsimd_restore_state;
+__hyp_text___fpsimd_save_state = __fpsimd_save_state;
+__hyp_text___guest_enter = __guest_enter;
__hyp_text___guest_exit = __guest_exit;
__hyp_text___icache_flags = __icache_flags;
__hyp_text___kvm_enable_ssbs = __kvm_enable_ssbs;
__hyp_text___kvm_get_mdcr_el2 = __kvm_get_mdcr_el2;
__hyp_text___kvm_handle_stub_hvc = __kvm_handle_stub_hvc;
__hyp_text___kvm_timer_set_cntvoff = __kvm_timer_set_cntvoff;
-__hyp_text___kvm_vcpu_run_nvhe = __kvm_vcpu_run_nvhe;
+__hyp_text___sysreg32_restore_state = __sysreg32_restore_state;
+__hyp_text___sysreg32_save_state = __sysreg32_save_state;
+__hyp_text___sysreg_restore_state_nvhe = __sysreg_restore_state_nvhe;
+__hyp_text___sysreg_save_state_nvhe = __sysreg_save_state_nvhe;
+__hyp_text___timer_disable_traps = __timer_disable_traps;
+__hyp_text___timer_enable_traps = __timer_enable_traps;
+__hyp_text___vgic_v2_perform_cpuif_access = __vgic_v2_perform_cpuif_access;
+__hyp_text___vgic_v3_activate_traps = __vgic_v3_activate_traps;
+__hyp_text___vgic_v3_deactivate_traps = __vgic_v3_deactivate_traps;
__hyp_text___vgic_v3_get_ich_vtr_el2 = __vgic_v3_get_ich_vtr_el2;
__hyp_text___vgic_v3_init_lrs = __vgic_v3_init_lrs;
+__hyp_text___vgic_v3_perform_cpuif_access = __vgic_v3_perform_cpuif_access;
__hyp_text___vgic_v3_read_vmcr = __vgic_v3_read_vmcr;
__hyp_text___vgic_v3_restore_aprs = __vgic_v3_restore_aprs;
+__hyp_text___vgic_v3_restore_state = __vgic_v3_restore_state;
__hyp_text___vgic_v3_save_aprs = __vgic_v3_save_aprs;
+__hyp_text___vgic_v3_save_state = __vgic_v3_save_state;
__hyp_text___vgic_v3_write_vmcr = __vgic_v3_write_vmcr;
__hyp_text_abort_guest_exit_end = abort_guest_exit_end;
__hyp_text_abort_guest_exit_start = abort_guest_exit_start;
@@ -81,13 +97,18 @@ __hyp_text_arm64_enable_wa2_handling = arm64_enable_wa2_handling;
__hyp_text_arm64_ssbd_callback_required = arm64_ssbd_callback_required;
__hyp_text_cpu_hwcap_keys = cpu_hwcap_keys;
__hyp_text_cpu_hwcaps = cpu_hwcaps;
-__hyp_text_hyp_panic = hyp_panic;
__hyp_text_kimage_voffset = kimage_voffset;
__hyp_text_kvm_host_data = kvm_host_data;
__hyp_text_kvm_patch_vector_branch = kvm_patch_vector_branch;
+__hyp_text_kvm_skip_instr32 = kvm_skip_instr32;
__hyp_text_kvm_update_va_mask = kvm_update_va_mask;
+__hyp_text_kvm_vgic_global_state = kvm_vgic_global_state;
__hyp_text_panic = panic;
__hyp_text_physvirt_offset = physvirt_offset;
+__hyp_text_sve_load_state = sve_load_state;
+__hyp_text_sve_save_state = sve_save_state;
+__hyp_text_vgic_v2_cpuif_trap = vgic_v2_cpuif_trap;
+__hyp_text_vgic_v3_cpuif_trap = vgic_v3_cpuif_trap;
#endif /* CONFIG_KVM */
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index c958bb37b769..dea249dc82b3 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -749,11 +749,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
trace_kvm_entry(*vcpu_pc(vcpu));
guest_enter_irqoff();
- if (has_vhe()) {
- ret = kvm_vcpu_run_vhe(vcpu);
- } else {
- ret = kvm_call_hyp_ret(__kvm_vcpu_run_nvhe, vcpu);
- }
+ ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
vcpu->mode = OUTSIDE_GUEST_MODE;
vcpu->stat.exits++;
diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S
index 7e5f386c5c2d..04ea0b83b728 100644
--- a/arch/arm64/kvm/hyp/hyp-entry.S
+++ b/arch/arm64/kvm/hyp/hyp-entry.S
@@ -221,6 +221,7 @@ el2_error:
eret
sb
+#ifdef __HYPERVISOR__
SYM_FUNC_START(__hyp_do_panic)
mov lr, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT |\
PSR_MODE_EL1h)
@@ -230,6 +231,7 @@ SYM_FUNC_START(__hyp_do_panic)
eret
sb
SYM_FUNC_END(__hyp_do_panic)
+#endif
SYM_CODE_START(__hyp_panic)
get_host_ctxt x0, x1
diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile
index 0da836cb5580..82fbd0b76501 100644
--- a/arch/arm64/kvm/hyp/nvhe/Makefile
+++ b/arch/arm64/kvm/hyp/nvhe/Makefile
@@ -7,7 +7,7 @@ asflags-y := -D__HYPERVISOR__
ccflags-y := -D__HYPERVISOR__ -fno-stack-protector -DDISABLE_BRANCH_PROFILING \
$(DISABLE_STACKLEAK_PLUGIN)
-obj-y := tlb.o host_hypercall.o ../hyp-entry.o
+obj-y := switch.o tlb.o host_hypercall.o ../hyp-entry.o
obj-y := $(patsubst %.o,%.hyp.o,$(obj-y))
extra-y := $(patsubst %.hyp.o,%.hyp.tmp.o,$(obj-y))
diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c
new file mode 100644
index 000000000000..4294beed3dc1
--- /dev/null
+++ b/arch/arm64/kvm/hyp/nvhe/switch.c
@@ -0,0 +1,271 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2015 - ARM Ltd
+ * Author: Marc Zyngier <marc.zyngier@....com>
+ */
+
+#include <linux/arm-smccc.h>
+#include <linux/kvm_host.h>
+#include <linux/types.h>
+#include <linux/jump_label.h>
+#include <uapi/linux/psci.h>
+
+#include <kvm/arm_psci.h>
+
+#include <asm/barrier.h>
+#include <asm/cpufeature.h>
+#include <asm/kprobes.h>
+#include <asm/kvm_asm.h>
+#include <asm/kvm_emulate.h>
+#include <asm/kvm_hyp.h>
+#include <asm/kvm_mmu.h>
+#include <asm/fpsimd.h>
+#include <asm/debug-monitors.h>
+#include <asm/processor.h>
+#include <asm/thread_info.h>
+
+#include "../switch.h"
+
+static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu)
+{
+ u64 val;
+
+ ___activate_traps(vcpu);
+ __activate_traps_common(vcpu);
+
+ val = CPTR_EL2_DEFAULT;
+ val |= CPTR_EL2_TTA | CPTR_EL2_TZ | CPTR_EL2_TAM;
+ if (!update_fp_enabled(vcpu)) {
+ val |= CPTR_EL2_TFP;
+ __activate_traps_fpsimd32(vcpu);
+ }
+
+ write_sysreg(val, cptr_el2);
+
+ if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
+ struct kvm_cpu_context *ctxt = &vcpu->arch.ctxt;
+
+ isb();
+ /*
+ * At this stage, and thanks to the above isb(), S2 is
+ * configured and enabled. We can now restore the guest's S1
+ * configuration: SCTLR, and only then TCR.
+ */
+ write_sysreg_el1(ctxt->sys_regs[SCTLR_EL1], SYS_SCTLR);
+ isb();
+ write_sysreg_el1(ctxt->sys_regs[TCR_EL1], SYS_TCR);
+ }
+}
+
+static void __hyp_text __deactivate_traps(struct kvm_vcpu *vcpu)
+{
+ u64 mdcr_el2;
+
+ ___deactivate_traps(vcpu);
+
+ mdcr_el2 = read_sysreg(mdcr_el2);
+
+ if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
+ u64 val;
+
+ /*
+ * Set the TCR and SCTLR registers in the exact opposite
+ * sequence as __activate_traps (first prevent walks,
+ * then force the MMU on). A generous sprinkling of isb()
+ * ensure that things happen in this exact order.
+ */
+ val = read_sysreg_el1(SYS_TCR);
+ write_sysreg_el1(val | TCR_EPD1_MASK | TCR_EPD0_MASK, SYS_TCR);
+ isb();
+ val = read_sysreg_el1(SYS_SCTLR);
+ write_sysreg_el1(val | SCTLR_ELx_M, SYS_SCTLR);
+ isb();
+ }
+
+ __deactivate_traps_common();
+
+ mdcr_el2 &= MDCR_EL2_HPMN_MASK;
+ mdcr_el2 |= MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT;
+
+ write_sysreg(mdcr_el2, mdcr_el2);
+ write_sysreg(HCR_HOST_NVHE_FLAGS, hcr_el2);
+ write_sysreg(CPTR_EL2_DEFAULT, cptr_el2);
+}
+
+static void __hyp_text __deactivate_vm(struct kvm_vcpu *vcpu)
+{
+ write_sysreg(0, vttbr_el2);
+}
+
+/* Save VGICv3 state on non-VHE systems */
+static void __hyp_text __hyp_vgic_save_state(struct kvm_vcpu *vcpu)
+{
+ if (static_branch_unlikely(&kvm_vgic_global_state.gicv3_cpuif)) {
+ __vgic_v3_save_state(vcpu);
+ __vgic_v3_deactivate_traps(vcpu);
+ }
+}
+
+/* Restore VGICv3 state on non_VEH systems */
+static void __hyp_text __hyp_vgic_restore_state(struct kvm_vcpu *vcpu)
+{
+ if (static_branch_unlikely(&kvm_vgic_global_state.gicv3_cpuif)) {
+ __vgic_v3_activate_traps(vcpu);
+ __vgic_v3_restore_state(vcpu);
+ }
+}
+
+/**
+ * Disable host events, enable guest events
+ */
+static bool __hyp_text __pmu_switch_to_guest(struct kvm_cpu_context *host_ctxt)
+{
+ struct kvm_host_data *host;
+ struct kvm_pmu_events *pmu;
+
+ host = container_of(host_ctxt, struct kvm_host_data, host_ctxt);
+ pmu = &host->pmu_events;
+
+ if (pmu->events_host)
+ write_sysreg(pmu->events_host, pmcntenclr_el0);
+
+ if (pmu->events_guest)
+ write_sysreg(pmu->events_guest, pmcntenset_el0);
+
+ return (pmu->events_host || pmu->events_guest);
+}
+
+/**
+ * Disable guest events, enable host events
+ */
+static void __hyp_text __pmu_switch_to_host(struct kvm_cpu_context *host_ctxt)
+{
+ struct kvm_host_data *host;
+ struct kvm_pmu_events *pmu;
+
+ host = container_of(host_ctxt, struct kvm_host_data, host_ctxt);
+ pmu = &host->pmu_events;
+
+ if (pmu->events_guest)
+ write_sysreg(pmu->events_guest, pmcntenclr_el0);
+
+ if (pmu->events_host)
+ write_sysreg(pmu->events_host, pmcntenset_el0);
+}
+
+/* Switch to the guest for legacy non-VHE systems */
+int __hyp_text __kvm_vcpu_run(struct kvm_vcpu *vcpu)
+{
+ struct kvm_cpu_context *host_ctxt;
+ struct kvm_cpu_context *guest_ctxt;
+ bool pmu_switch_needed;
+ 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 | GIC_PRIO_PSR_I_SET);
+ pmr_sync();
+ }
+
+ vcpu = kern_hyp_va(vcpu);
+
+ host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context);
+ host_ctxt->__hyp_running_vcpu = vcpu;
+ guest_ctxt = &vcpu->arch.ctxt;
+
+ pmu_switch_needed = __pmu_switch_to_guest(host_ctxt);
+
+ __sysreg_save_state_nvhe(host_ctxt);
+
+ /*
+ * We must restore the 32-bit state before the sysregs, thanks
+ * to erratum #852523 (Cortex-A57) or #853709 (Cortex-A72).
+ *
+ * Also, and in order to be able to deal with erratum #1319537 (A57)
+ * and #1319367 (A72), we must ensure that all VM-related sysreg are
+ * restored before we enable S2 translation.
+ */
+ __sysreg32_restore_state(vcpu);
+ __sysreg_restore_state_nvhe(guest_ctxt);
+
+ __activate_vm(kern_hyp_va(vcpu->kvm));
+ __activate_traps(vcpu);
+
+ __hyp_vgic_restore_state(vcpu);
+ __timer_enable_traps(vcpu);
+
+ __debug_switch_to_guest(vcpu);
+
+ __set_guest_arch_workaround_state(vcpu);
+
+ do {
+ /* Jump in the fire! */
+ exit_code = __guest_enter(vcpu, host_ctxt);
+
+ /* And we're baaack! */
+ } while (fixup_guest_exit(vcpu, &exit_code));
+
+ __set_host_arch_workaround_state(vcpu);
+
+ __sysreg_save_state_nvhe(guest_ctxt);
+ __sysreg32_save_state(vcpu);
+ __timer_disable_traps(vcpu);
+ __hyp_vgic_save_state(vcpu);
+
+ __deactivate_traps(vcpu);
+ __deactivate_vm(vcpu);
+
+ __sysreg_restore_state_nvhe(host_ctxt);
+
+ if (vcpu->arch.flags & KVM_ARM64_FP_ENABLED)
+ __fpsimd_save_fpexc32(vcpu);
+
+ /*
+ * This must come after restoring the host sysregs, since a non-VHE
+ * system may enable SPE here and make use of the TTBRs.
+ */
+ __debug_switch_to_host(vcpu);
+
+ if (pmu_switch_needed)
+ __pmu_switch_to_host(host_ctxt);
+
+ /* 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;
+}
+
+void __hyp_text __noreturn hyp_panic(struct kvm_cpu_context *host_ctxt)
+{
+ u64 spsr = read_sysreg_el2(SYS_SPSR);
+ u64 elr = read_sysreg_el2(SYS_ELR);
+ u64 par = read_sysreg(par_el1);
+ struct kvm_vcpu *vcpu = host_ctxt->__hyp_running_vcpu;
+ unsigned long str_va;
+
+ if (read_sysreg(vttbr_el2)) {
+ __timer_disable_traps(vcpu);
+ __deactivate_traps(vcpu);
+ __deactivate_vm(vcpu);
+ __sysreg_restore_state_nvhe(host_ctxt);
+ }
+
+ /*
+ * Force the panic string to be loaded from the literal pool,
+ * making sure it is a kernel address and not a PC-relative
+ * reference.
+ */
+ asm volatile("ldr %0, =%1" : "=r" (str_va) : "S" (__hyp_panic_string));
+
+ __hyp_do_panic(str_va,
+ spsr, elr,
+ read_sysreg(esr_el2), read_sysreg_el2(SYS_FAR),
+ read_sysreg(hpfar_el2), par, vcpu);
+ unreachable();
+}
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index 7a7c08029d81..1d03c5bf0b18 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -24,76 +24,14 @@
#include <asm/processor.h>
#include <asm/thread_info.h>
-/* Check whether the FP regs were dirtied while in the host-side run loop: */
-static bool __hyp_text update_fp_enabled(struct kvm_vcpu *vcpu)
-{
- /*
- * When the system doesn't support FP/SIMD, we cannot rely on
- * the _TIF_FOREIGN_FPSTATE flag. However, we always inject an
- * abort on the very first access to FP and thus we should never
- * see KVM_ARM64_FP_ENABLED. For added safety, make sure we always
- * trap the accesses.
- */
- if (!system_supports_fpsimd() ||
- vcpu->arch.host_thread_info->flags & _TIF_FOREIGN_FPSTATE)
- vcpu->arch.flags &= ~(KVM_ARM64_FP_ENABLED |
- KVM_ARM64_FP_HOST);
-
- return !!(vcpu->arch.flags & KVM_ARM64_FP_ENABLED);
-}
-
-/* Save the 32-bit only FPSIMD system register state */
-static void __hyp_text __fpsimd_save_fpexc32(struct kvm_vcpu *vcpu)
-{
- if (!vcpu_el1_is_32bit(vcpu))
- return;
-
- vcpu->arch.ctxt.sys_regs[FPEXC32_EL2] = read_sysreg(fpexc32_el2);
-}
-
-static void __hyp_text __activate_traps_fpsimd32(struct kvm_vcpu *vcpu)
-{
- /*
- * We are about to set CPTR_EL2.TFP to trap all floating point
- * register accesses to EL2, however, the ARM ARM clearly states that
- * traps are only taken to EL2 if the operation would not otherwise
- * trap to EL1. Therefore, always make sure that for 32-bit guests,
- * we set FPEXC.EN to prevent traps to EL1, when setting the TFP bit.
- * If FP/ASIMD is not implemented, FPEXC is UNDEFINED and any access to
- * it will cause an exception.
- */
- if (vcpu_el1_is_32bit(vcpu) && system_supports_fpsimd()) {
- write_sysreg(1 << 30, fpexc32_el2);
- isb();
- }
-}
-
-static void __hyp_text __activate_traps_common(struct kvm_vcpu *vcpu)
-{
- /* Trap on AArch32 cp15 c15 (impdef sysregs) accesses (EL1 or EL0) */
- write_sysreg(1 << 15, hstr_el2);
-
- /*
- * Make sure we trap PMU access from EL0 to EL2. Also sanitize
- * PMSELR_EL0 to make sure it never contains the cycle
- * counter, which could make a PMXEVCNTR_EL0 access UNDEF at
- * EL1 instead of being trapped to EL2.
- */
- write_sysreg(0, pmselr_el0);
- write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0);
- write_sysreg(vcpu->arch.mdcr_el2, mdcr_el2);
-}
-
-static void __hyp_text __deactivate_traps_common(void)
-{
- write_sysreg(0, hstr_el2);
- write_sysreg(0, pmuserenr_el0);
-}
+#include "switch.h"
-static void activate_traps_vhe(struct kvm_vcpu *vcpu)
+static void __activate_traps(struct kvm_vcpu *vcpu)
{
u64 val;
+ ___activate_traps(vcpu);
+
val = read_sysreg(cpacr_el1);
val |= CPACR_EL1_TTA;
val &= ~CPACR_EL1_ZEN;
@@ -121,59 +59,14 @@ 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)
-{
- u64 val;
-
- __activate_traps_common(vcpu);
-
- val = CPTR_EL2_DEFAULT;
- val |= CPTR_EL2_TTA | CPTR_EL2_TZ | CPTR_EL2_TAM;
- if (!update_fp_enabled(vcpu)) {
- val |= CPTR_EL2_TFP;
- __activate_traps_fpsimd32(vcpu);
- }
-
- write_sysreg(val, cptr_el2);
-
- if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
- struct kvm_cpu_context *ctxt = &vcpu->arch.ctxt;
-
- isb();
- /*
- * At this stage, and thanks to the above isb(), S2 is
- * configured and enabled. We can now restore the guest's S1
- * configuration: SCTLR, and only then TCR.
- */
- write_sysreg_el1(ctxt->sys_regs[SCTLR_EL1], SYS_SCTLR);
- isb();
- write_sysreg_el1(ctxt->sys_regs[TCR_EL1], SYS_TCR);
- }
-}
+NOKPROBE_SYMBOL(__activate_traps);
-static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu)
+static void __deactivate_traps(struct kvm_vcpu *vcpu)
{
- u64 hcr = vcpu->arch.hcr_el2;
-
- if (cpus_have_final_cap(ARM64_WORKAROUND_CAVIUM_TX2_219_TVM))
- hcr |= HCR_TVM;
-
- write_sysreg(hcr, hcr_el2);
-
- if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN) && (hcr & HCR_VSE))
- write_sysreg_s(vcpu->arch.vsesr_el2, SYS_VSESR_EL2);
+ extern char vectors[]; /* kernel exception vectors */
- if (has_vhe())
- activate_traps_vhe(vcpu);
- else
- __activate_traps_nvhe(vcpu);
-}
+ ___deactivate_traps(vcpu);
-static void deactivate_traps_vhe(void)
-{
- extern char vectors[]; /* kernel exception vectors */
write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2);
/*
@@ -186,57 +79,7 @@ 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)
-{
- u64 mdcr_el2 = read_sysreg(mdcr_el2);
-
- if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT_NVHE)) {
- u64 val;
-
- /*
- * Set the TCR and SCTLR registers in the exact opposite
- * sequence as __activate_traps_nvhe (first prevent walks,
- * then force the MMU on). A generous sprinkling of isb()
- * ensure that things happen in this exact order.
- */
- val = read_sysreg_el1(SYS_TCR);
- write_sysreg_el1(val | TCR_EPD1_MASK | TCR_EPD0_MASK, SYS_TCR);
- isb();
- val = read_sysreg_el1(SYS_SCTLR);
- write_sysreg_el1(val | SCTLR_ELx_M, SYS_SCTLR);
- isb();
- }
-
- __deactivate_traps_common();
-
- mdcr_el2 &= MDCR_EL2_HPMN_MASK;
- mdcr_el2 |= MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT;
-
- write_sysreg(mdcr_el2, mdcr_el2);
- write_sysreg(HCR_HOST_NVHE_FLAGS, hcr_el2);
- write_sysreg(CPTR_EL2_DEFAULT, cptr_el2);
-}
-
-static void __hyp_text __deactivate_traps(struct kvm_vcpu *vcpu)
-{
- /*
- * If we pended a virtual abort, preserve it until it gets
- * cleared. See D1.14.3 (Virtual Interrupts) for details, but
- * the crucial bit is "On taking a vSError interrupt,
- * HCR_EL2.VSE is cleared to 0."
- */
- if (vcpu->arch.hcr_el2 & HCR_VSE) {
- vcpu->arch.hcr_el2 &= ~HCR_VSE;
- vcpu->arch.hcr_el2 |= read_sysreg(hcr_el2) & HCR_VSE;
- }
-
- if (has_vhe())
- deactivate_traps_vhe();
- else
- __deactivate_traps_nvhe();
-}
+NOKPROBE_SYMBOL(__deactivate_traps);
void activate_traps_vhe_load(struct kvm_vcpu *vcpu)
{
@@ -256,385 +99,6 @@ void deactivate_traps_vhe_put(void)
__deactivate_traps_common();
}
-static void __hyp_text __activate_vm(struct kvm *kvm)
-{
- __load_guest_stage2(kvm);
-}
-
-static void __hyp_text __deactivate_vm(struct kvm_vcpu *vcpu)
-{
- write_sysreg(0, vttbr_el2);
-}
-
-/* Save VGICv3 state on non-VHE systems */
-static void __hyp_text __hyp_vgic_save_state(struct kvm_vcpu *vcpu)
-{
- if (static_branch_unlikely(&kvm_vgic_global_state.gicv3_cpuif)) {
- __vgic_v3_save_state(vcpu);
- __vgic_v3_deactivate_traps(vcpu);
- }
-}
-
-/* Restore VGICv3 state on non_VEH systems */
-static void __hyp_text __hyp_vgic_restore_state(struct kvm_vcpu *vcpu)
-{
- if (static_branch_unlikely(&kvm_vgic_global_state.gicv3_cpuif)) {
- __vgic_v3_activate_traps(vcpu);
- __vgic_v3_restore_state(vcpu);
- }
-}
-
-static bool __hyp_text __translate_far_to_hpfar(u64 far, u64 *hpfar)
-{
- u64 par, tmp;
-
- /*
- * Resolve the IPA the hard way using the guest VA.
- *
- * Stage-1 translation already validated the memory access
- * rights. As such, we can use the EL1 translation regime, and
- * don't have to distinguish between EL0 and EL1 access.
- *
- * We do need to save/restore PAR_EL1 though, as we haven't
- * saved the guest context yet, and we may return early...
- */
- par = read_sysreg(par_el1);
- asm volatile("at s1e1r, %0" : : "r" (far));
- isb();
-
- tmp = read_sysreg(par_el1);
- write_sysreg(par, par_el1);
-
- if (unlikely(tmp & SYS_PAR_EL1_F))
- return false; /* Translation failed, back to guest */
-
- /* Convert PAR to HPFAR format */
- *hpfar = PAR_TO_HPFAR(tmp);
- return true;
-}
-
-static bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu)
-{
- u8 ec;
- u64 esr;
- u64 hpfar, far;
-
- esr = vcpu->arch.fault.esr_el2;
- ec = ESR_ELx_EC(esr);
-
- if (ec != ESR_ELx_EC_DABT_LOW && ec != ESR_ELx_EC_IABT_LOW)
- return true;
-
- far = read_sysreg_el2(SYS_FAR);
-
- /*
- * The HPFAR can be invalid if the stage 2 fault did not
- * happen during a stage 1 page table walk (the ESR_EL2.S1PTW
- * bit is clear) and one of the two following cases are true:
- * 1. The fault was due to a permission fault
- * 2. The processor carries errata 834220
- *
- * Therefore, for all non S1PTW faults where we either have a
- * permission fault or the errata workaround is enabled, we
- * resolve the IPA using the AT instruction.
- */
- if (!(esr & ESR_ELx_S1PTW) &&
- (cpus_have_final_cap(ARM64_WORKAROUND_834220) ||
- (esr & ESR_ELx_FSC_TYPE) == FSC_PERM)) {
- if (!__translate_far_to_hpfar(far, &hpfar))
- return false;
- } else {
- hpfar = read_sysreg(hpfar_el2);
- }
-
- vcpu->arch.fault.far_el2 = far;
- vcpu->arch.fault.hpfar_el2 = hpfar;
- return true;
-}
-
-/* Check for an FPSIMD/SVE trap and handle as appropriate */
-static bool __hyp_text __hyp_handle_fpsimd(struct kvm_vcpu *vcpu)
-{
- bool vhe, sve_guest, sve_host;
- u8 hsr_ec;
-
- if (!system_supports_fpsimd())
- return false;
-
- if (system_supports_sve()) {
- sve_guest = vcpu_has_sve(vcpu);
- sve_host = vcpu->arch.flags & KVM_ARM64_HOST_SVE_IN_USE;
- vhe = true;
- } else {
- sve_guest = false;
- sve_host = false;
- vhe = has_vhe();
- }
-
- hsr_ec = kvm_vcpu_trap_get_class(vcpu);
- if (hsr_ec != ESR_ELx_EC_FP_ASIMD &&
- hsr_ec != ESR_ELx_EC_SVE)
- return false;
-
- /* Don't handle SVE traps for non-SVE vcpus here: */
- if (!sve_guest)
- if (hsr_ec != ESR_ELx_EC_FP_ASIMD)
- return false;
-
- /* Valid trap. Switch the context: */
-
- if (vhe) {
- u64 reg = read_sysreg(cpacr_el1) | CPACR_EL1_FPEN;
-
- if (sve_guest)
- reg |= CPACR_EL1_ZEN;
-
- write_sysreg(reg, cpacr_el1);
- } else {
- write_sysreg(read_sysreg(cptr_el2) & ~(u64)CPTR_EL2_TFP,
- cptr_el2);
- }
-
- isb();
-
- if (vcpu->arch.flags & KVM_ARM64_FP_HOST) {
- /*
- * In the SVE case, VHE is assumed: it is enforced by
- * Kconfig and kvm_arch_init().
- */
- if (sve_host) {
- struct thread_struct *thread = container_of(
- vcpu->arch.host_fpsimd_state,
- struct thread_struct, uw.fpsimd_state);
-
- sve_save_state(sve_pffr(thread),
- &vcpu->arch.host_fpsimd_state->fpsr);
- } else {
- __fpsimd_save_state(vcpu->arch.host_fpsimd_state);
- }
-
- vcpu->arch.flags &= ~KVM_ARM64_FP_HOST;
- }
-
- if (sve_guest) {
- sve_load_state(vcpu_sve_pffr(vcpu),
- &vcpu->arch.ctxt.gp_regs.fp_regs.fpsr,
- sve_vq_from_vl(vcpu->arch.sve_max_vl) - 1);
- write_sysreg_s(vcpu->arch.ctxt.sys_regs[ZCR_EL1], SYS_ZCR_EL12);
- } else {
- __fpsimd_restore_state(&vcpu->arch.ctxt.gp_regs.fp_regs);
- }
-
- /* Skip restoring fpexc32 for AArch64 guests */
- if (!(read_sysreg(hcr_el2) & HCR_RW))
- write_sysreg(vcpu->arch.ctxt.sys_regs[FPEXC32_EL2],
- fpexc32_el2);
-
- vcpu->arch.flags |= KVM_ARM64_FP_ENABLED;
-
- return true;
-}
-
-static bool __hyp_text handle_tx2_tvm(struct kvm_vcpu *vcpu)
-{
- u32 sysreg = esr_sys64_to_sysreg(kvm_vcpu_get_hsr(vcpu));
- int rt = kvm_vcpu_sys_get_rt(vcpu);
- u64 val = vcpu_get_reg(vcpu, rt);
-
- /*
- * The normal sysreg handling code expects to see the traps,
- * let's not do anything here.
- */
- if (vcpu->arch.hcr_el2 & HCR_TVM)
- return false;
-
- switch (sysreg) {
- case SYS_SCTLR_EL1:
- write_sysreg_el1(val, SYS_SCTLR);
- break;
- case SYS_TTBR0_EL1:
- write_sysreg_el1(val, SYS_TTBR0);
- break;
- case SYS_TTBR1_EL1:
- write_sysreg_el1(val, SYS_TTBR1);
- break;
- case SYS_TCR_EL1:
- write_sysreg_el1(val, SYS_TCR);
- break;
- case SYS_ESR_EL1:
- write_sysreg_el1(val, SYS_ESR);
- break;
- case SYS_FAR_EL1:
- write_sysreg_el1(val, SYS_FAR);
- break;
- case SYS_AFSR0_EL1:
- write_sysreg_el1(val, SYS_AFSR0);
- break;
- case SYS_AFSR1_EL1:
- write_sysreg_el1(val, SYS_AFSR1);
- break;
- case SYS_MAIR_EL1:
- write_sysreg_el1(val, SYS_MAIR);
- break;
- case SYS_AMAIR_EL1:
- write_sysreg_el1(val, SYS_AMAIR);
- break;
- case SYS_CONTEXTIDR_EL1:
- write_sysreg_el1(val, SYS_CONTEXTIDR);
- break;
- default:
- return false;
- }
-
- __kvm_skip_instr(vcpu);
- return true;
-}
-
-/*
- * Return true when we were able to fixup the guest exit and should return to
- * the guest, false when we should restore the host state and return to the
- * main run loop.
- */
-static bool __hyp_text fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
-{
- if (ARM_EXCEPTION_CODE(*exit_code) != ARM_EXCEPTION_IRQ)
- vcpu->arch.fault.esr_el2 = read_sysreg_el2(SYS_ESR);
-
- /*
- * We're using the raw exception code in order to only process
- * the trap if no SError is pending. We will come back to the
- * same PC once the SError has been injected, and replay the
- * trapping instruction.
- */
- if (*exit_code != ARM_EXCEPTION_TRAP)
- goto exit;
-
- if (cpus_have_final_cap(ARM64_WORKAROUND_CAVIUM_TX2_219_TVM) &&
- kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_SYS64 &&
- handle_tx2_tvm(vcpu))
- return true;
-
- /*
- * We trap the first access to the FP/SIMD to save the host context
- * and restore the guest context lazily.
- * If FP/SIMD is not implemented, handle the trap and inject an
- * undefined instruction exception to the guest.
- * Similarly for trapped SVE accesses.
- */
- if (__hyp_handle_fpsimd(vcpu))
- return true;
-
- if (!__populate_fault_info(vcpu))
- return true;
-
- if (static_branch_unlikely(&vgic_v2_cpuif_trap)) {
- bool valid;
-
- valid = kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_DABT_LOW &&
- kvm_vcpu_trap_get_fault_type(vcpu) == FSC_FAULT &&
- kvm_vcpu_dabt_isvalid(vcpu) &&
- !kvm_vcpu_dabt_isextabt(vcpu) &&
- !kvm_vcpu_dabt_iss1tw(vcpu);
-
- if (valid) {
- int ret = __vgic_v2_perform_cpuif_access(vcpu);
-
- if (ret == 1)
- return true;
-
- /* Promote an illegal access to an SError.*/
- if (ret == -1)
- *exit_code = ARM_EXCEPTION_EL1_SERROR;
-
- goto exit;
- }
- }
-
- if (static_branch_unlikely(&vgic_v3_cpuif_trap) &&
- (kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_SYS64 ||
- kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_CP15_32)) {
- int ret = __vgic_v3_perform_cpuif_access(vcpu);
-
- if (ret == 1)
- return true;
- }
-
-exit:
- /* Return to the host kernel and handle the exit */
- return false;
-}
-
-static inline bool __hyp_text __needs_ssbd_off(struct kvm_vcpu *vcpu)
-{
- if (!cpus_have_final_cap(ARM64_SSBD))
- return false;
-
- return !(vcpu->arch.workaround_flags & VCPU_WORKAROUND_2_FLAG);
-}
-
-static void __hyp_text __set_guest_arch_workaround_state(struct kvm_vcpu *vcpu)
-{
-#ifdef CONFIG_ARM64_SSBD
- /*
- * The host runs with the workaround always present. If the
- * guest wants it disabled, so be it...
- */
- if (__needs_ssbd_off(vcpu) &&
- __hyp_this_cpu_read(arm64_ssbd_callback_required))
- arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 0, NULL);
-#endif
-}
-
-static void __hyp_text __set_host_arch_workaround_state(struct kvm_vcpu *vcpu)
-{
-#ifdef CONFIG_ARM64_SSBD
- /*
- * If the guest has disabled the workaround, bring it back on.
- */
- if (__needs_ssbd_off(vcpu) &&
- __hyp_this_cpu_read(arm64_ssbd_callback_required))
- arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 1, NULL);
-#endif
-}
-
-/**
- * Disable host events, enable guest events
- */
-static bool __hyp_text __pmu_switch_to_guest(struct kvm_cpu_context *host_ctxt)
-{
- struct kvm_host_data *host;
- struct kvm_pmu_events *pmu;
-
- host = container_of(host_ctxt, struct kvm_host_data, host_ctxt);
- pmu = &host->pmu_events;
-
- if (pmu->events_host)
- write_sysreg(pmu->events_host, pmcntenclr_el0);
-
- if (pmu->events_guest)
- write_sysreg(pmu->events_guest, pmcntenset_el0);
-
- return (pmu->events_host || pmu->events_guest);
-}
-
-/**
- * Disable guest events, enable host events
- */
-static void __hyp_text __pmu_switch_to_host(struct kvm_cpu_context *host_ctxt)
-{
- struct kvm_host_data *host;
- struct kvm_pmu_events *pmu;
-
- host = container_of(host_ctxt, struct kvm_host_data, host_ctxt);
- pmu = &host->pmu_events;
-
- if (pmu->events_guest)
- write_sysreg(pmu->events_guest, pmcntenclr_el0);
-
- if (pmu->events_host)
- write_sysreg(pmu->events_host, pmcntenset_el0);
-}
-
/* Switch to the guest for VHE systems running in EL2 */
static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
{
@@ -691,7 +155,7 @@ static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
}
NOKPROBE_SYMBOL(__kvm_vcpu_run_vhe);
-int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
+int __kvm_vcpu_run(struct kvm_vcpu *vcpu)
{
int ret;
@@ -726,126 +190,8 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
return ret;
}
-/* Switch to the guest for legacy non-VHE systems */
-int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu)
-{
- struct kvm_cpu_context *host_ctxt;
- struct kvm_cpu_context *guest_ctxt;
- bool pmu_switch_needed;
- 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 | GIC_PRIO_PSR_I_SET);
- pmr_sync();
- }
-
- vcpu = kern_hyp_va(vcpu);
-
- host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context);
- host_ctxt->__hyp_running_vcpu = vcpu;
- guest_ctxt = &vcpu->arch.ctxt;
-
- pmu_switch_needed = __pmu_switch_to_guest(host_ctxt);
-
- __sysreg_save_state_nvhe(host_ctxt);
-
- /*
- * We must restore the 32-bit state before the sysregs, thanks
- * to erratum #852523 (Cortex-A57) or #853709 (Cortex-A72).
- *
- * Also, and in order to be able to deal with erratum #1319537 (A57)
- * and #1319367 (A72), we must ensure that all VM-related sysreg are
- * restored before we enable S2 translation.
- */
- __sysreg32_restore_state(vcpu);
- __sysreg_restore_state_nvhe(guest_ctxt);
-
- __activate_vm(kern_hyp_va(vcpu->kvm));
- __activate_traps(vcpu);
-
- __hyp_vgic_restore_state(vcpu);
- __timer_enable_traps(vcpu);
-
- __debug_switch_to_guest(vcpu);
-
- __set_guest_arch_workaround_state(vcpu);
-
- do {
- /* Jump in the fire! */
- exit_code = __guest_enter(vcpu, host_ctxt);
-
- /* And we're baaack! */
- } while (fixup_guest_exit(vcpu, &exit_code));
-
- __set_host_arch_workaround_state(vcpu);
-
- __sysreg_save_state_nvhe(guest_ctxt);
- __sysreg32_save_state(vcpu);
- __timer_disable_traps(vcpu);
- __hyp_vgic_save_state(vcpu);
-
- __deactivate_traps(vcpu);
- __deactivate_vm(vcpu);
-
- __sysreg_restore_state_nvhe(host_ctxt);
-
- if (vcpu->arch.flags & KVM_ARM64_FP_ENABLED)
- __fpsimd_save_fpexc32(vcpu);
-
- /*
- * This must come after restoring the host sysregs, since a non-VHE
- * system may enable SPE here and make use of the TTBRs.
- */
- __debug_switch_to_host(vcpu);
-
- if (pmu_switch_needed)
- __pmu_switch_to_host(host_ctxt);
-
- /* 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;
-}
-
-static const char __hyp_panic_string[] = "HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n";
-
-static void __hyp_text __hyp_call_panic_nvhe(u64 spsr, u64 elr, u64 par,
- struct kvm_cpu_context *__host_ctxt)
-{
- struct kvm_vcpu *vcpu;
- unsigned long str_va;
-
- vcpu = __host_ctxt->__hyp_running_vcpu;
-
- if (read_sysreg(vttbr_el2)) {
- __timer_disable_traps(vcpu);
- __deactivate_traps(vcpu);
- __deactivate_vm(vcpu);
- __sysreg_restore_state_nvhe(__host_ctxt);
- }
-
- /*
- * Force the panic string to be loaded from the literal pool,
- * making sure it is a kernel address and not a PC-relative
- * reference.
- */
- asm volatile("ldr %0, =%1" : "=r" (str_va) : "S" (__hyp_panic_string));
-
- __hyp_do_panic(str_va,
- spsr, elr,
- read_sysreg(esr_el2), read_sysreg_el2(SYS_FAR),
- read_sysreg(hpfar_el2), par, vcpu);
-}
-
-static void __hyp_call_panic_vhe(u64 spsr, u64 elr, u64 par,
- struct kvm_cpu_context *host_ctxt)
+static void __hyp_call_panic(u64 spsr, u64 elr, u64 par,
+ struct kvm_cpu_context *host_ctxt)
{
struct kvm_vcpu *vcpu;
vcpu = host_ctxt->__hyp_running_vcpu;
@@ -858,18 +204,14 @@ static void __hyp_call_panic_vhe(u64 spsr, u64 elr, u64 par,
read_sysreg_el2(SYS_ESR), read_sysreg_el2(SYS_FAR),
read_sysreg(hpfar_el2), par, vcpu);
}
-NOKPROBE_SYMBOL(__hyp_call_panic_vhe);
+NOKPROBE_SYMBOL(__hyp_call_panic);
-void __hyp_text __noreturn hyp_panic(struct kvm_cpu_context *host_ctxt)
+void __noreturn hyp_panic(struct kvm_cpu_context *host_ctxt)
{
u64 spsr = read_sysreg_el2(SYS_SPSR);
u64 elr = read_sysreg_el2(SYS_ELR);
u64 par = read_sysreg(par_el1);
- if (!has_vhe())
- __hyp_call_panic_nvhe(spsr, elr, par, host_ctxt);
- else
- __hyp_call_panic_vhe(spsr, elr, par, host_ctxt);
-
+ __hyp_call_panic(spsr, elr, par, host_ctxt);
unreachable();
}
diff --git a/arch/arm64/kvm/hyp/switch.h b/arch/arm64/kvm/hyp/switch.h
new file mode 100644
index 000000000000..00ecb0111e79
--- /dev/null
+++ b/arch/arm64/kvm/hyp/switch.h
@@ -0,0 +1,441 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2015 - ARM Ltd
+ * Author: Marc Zyngier <marc.zyngier@....com>
+ */
+
+#include <linux/arm-smccc.h>
+#include <linux/kvm_host.h>
+#include <linux/types.h>
+#include <linux/jump_label.h>
+#include <uapi/linux/psci.h>
+
+#include <kvm/arm_psci.h>
+
+#include <asm/barrier.h>
+#include <asm/cpufeature.h>
+#include <asm/kprobes.h>
+#include <asm/kvm_asm.h>
+#include <asm/kvm_emulate.h>
+#include <asm/kvm_hyp.h>
+#include <asm/kvm_mmu.h>
+#include <asm/fpsimd.h>
+#include <asm/debug-monitors.h>
+#include <asm/processor.h>
+#include <asm/thread_info.h>
+
+static const char __hyp_panic_string[] = "HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n";
+
+/* Check whether the FP regs were dirtied while in the host-side run loop: */
+static inline bool __hyp_text update_fp_enabled(struct kvm_vcpu *vcpu)
+{
+ /*
+ * When the system doesn't support FP/SIMD, we cannot rely on
+ * the _TIF_FOREIGN_FPSTATE flag. However, we always inject an
+ * abort on the very first access to FP and thus we should never
+ * see KVM_ARM64_FP_ENABLED. For added safety, make sure we always
+ * trap the accesses.
+ */
+ if (!system_supports_fpsimd() ||
+ vcpu->arch.host_thread_info->flags & _TIF_FOREIGN_FPSTATE)
+ vcpu->arch.flags &= ~(KVM_ARM64_FP_ENABLED |
+ KVM_ARM64_FP_HOST);
+
+ return !!(vcpu->arch.flags & KVM_ARM64_FP_ENABLED);
+}
+
+/* Save the 32-bit only FPSIMD system register state */
+static inline void __hyp_text __fpsimd_save_fpexc32(struct kvm_vcpu *vcpu)
+{
+ if (!vcpu_el1_is_32bit(vcpu))
+ return;
+
+ vcpu->arch.ctxt.sys_regs[FPEXC32_EL2] = read_sysreg(fpexc32_el2);
+}
+
+static inline void __hyp_text __activate_traps_fpsimd32(struct kvm_vcpu *vcpu)
+{
+ /*
+ * We are about to set CPTR_EL2.TFP to trap all floating point
+ * register accesses to EL2, however, the ARM ARM clearly states that
+ * traps are only taken to EL2 if the operation would not otherwise
+ * trap to EL1. Therefore, always make sure that for 32-bit guests,
+ * we set FPEXC.EN to prevent traps to EL1, when setting the TFP bit.
+ * If FP/ASIMD is not implemented, FPEXC is UNDEFINED and any access to
+ * it will cause an exception.
+ */
+ if (vcpu_el1_is_32bit(vcpu) && system_supports_fpsimd()) {
+ write_sysreg(1 << 30, fpexc32_el2);
+ isb();
+ }
+}
+
+static inline void __hyp_text __activate_traps_common(struct kvm_vcpu *vcpu)
+{
+ /* Trap on AArch32 cp15 c15 (impdef sysregs) accesses (EL1 or EL0) */
+ write_sysreg(1 << 15, hstr_el2);
+
+ /*
+ * Make sure we trap PMU access from EL0 to EL2. Also sanitize
+ * PMSELR_EL0 to make sure it never contains the cycle
+ * counter, which could make a PMXEVCNTR_EL0 access UNDEF at
+ * EL1 instead of being trapped to EL2.
+ */
+ write_sysreg(0, pmselr_el0);
+ write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0);
+ write_sysreg(vcpu->arch.mdcr_el2, mdcr_el2);
+}
+
+static inline void __hyp_text __deactivate_traps_common(void)
+{
+ write_sysreg(0, hstr_el2);
+ write_sysreg(0, pmuserenr_el0);
+}
+
+static inline void __hyp_text ___activate_traps(struct kvm_vcpu *vcpu)
+{
+ u64 hcr = vcpu->arch.hcr_el2;
+
+ if (cpus_have_final_cap(ARM64_WORKAROUND_CAVIUM_TX2_219_TVM))
+ hcr |= HCR_TVM;
+
+ write_sysreg(hcr, hcr_el2);
+
+ if (cpus_have_final_cap(ARM64_HAS_RAS_EXTN) && (hcr & HCR_VSE))
+ write_sysreg_s(vcpu->arch.vsesr_el2, SYS_VSESR_EL2);
+}
+
+static inline void __hyp_text ___deactivate_traps(struct kvm_vcpu *vcpu)
+{
+ /*
+ * If we pended a virtual abort, preserve it until it gets
+ * cleared. See D1.14.3 (Virtual Interrupts) for details, but
+ * the crucial bit is "On taking a vSError interrupt,
+ * HCR_EL2.VSE is cleared to 0."
+ */
+ if (vcpu->arch.hcr_el2 & HCR_VSE) {
+ vcpu->arch.hcr_el2 &= ~HCR_VSE;
+ vcpu->arch.hcr_el2 |= read_sysreg(hcr_el2) & HCR_VSE;
+ }
+}
+
+static inline void __hyp_text __activate_vm(struct kvm *kvm)
+{
+ __load_guest_stage2(kvm);
+}
+
+static inline bool __hyp_text __translate_far_to_hpfar(u64 far, u64 *hpfar)
+{
+ u64 par, tmp;
+
+ /*
+ * Resolve the IPA the hard way using the guest VA.
+ *
+ * Stage-1 translation already validated the memory access
+ * rights. As such, we can use the EL1 translation regime, and
+ * don't have to distinguish between EL0 and EL1 access.
+ *
+ * We do need to save/restore PAR_EL1 though, as we haven't
+ * saved the guest context yet, and we may return early...
+ */
+ par = read_sysreg(par_el1);
+ asm volatile("at s1e1r, %0" : : "r" (far));
+ isb();
+
+ tmp = read_sysreg(par_el1);
+ write_sysreg(par, par_el1);
+
+ if (unlikely(tmp & SYS_PAR_EL1_F))
+ return false; /* Translation failed, back to guest */
+
+ /* Convert PAR to HPFAR format */
+ *hpfar = PAR_TO_HPFAR(tmp);
+ return true;
+}
+
+static inline bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu)
+{
+ u8 ec;
+ u64 esr;
+ u64 hpfar, far;
+
+ esr = vcpu->arch.fault.esr_el2;
+ ec = ESR_ELx_EC(esr);
+
+ if (ec != ESR_ELx_EC_DABT_LOW && ec != ESR_ELx_EC_IABT_LOW)
+ return true;
+
+ far = read_sysreg_el2(SYS_FAR);
+
+ /*
+ * The HPFAR can be invalid if the stage 2 fault did not
+ * happen during a stage 1 page table walk (the ESR_EL2.S1PTW
+ * bit is clear) and one of the two following cases are true:
+ * 1. The fault was due to a permission fault
+ * 2. The processor carries errata 834220
+ *
+ * Therefore, for all non S1PTW faults where we either have a
+ * permission fault or the errata workaround is enabled, we
+ * resolve the IPA using the AT instruction.
+ */
+ if (!(esr & ESR_ELx_S1PTW) &&
+ (cpus_have_final_cap(ARM64_WORKAROUND_834220) ||
+ (esr & ESR_ELx_FSC_TYPE) == FSC_PERM)) {
+ if (!__translate_far_to_hpfar(far, &hpfar))
+ return false;
+ } else {
+ hpfar = read_sysreg(hpfar_el2);
+ }
+
+ vcpu->arch.fault.far_el2 = far;
+ vcpu->arch.fault.hpfar_el2 = hpfar;
+ return true;
+}
+
+/* Check for an FPSIMD/SVE trap and handle as appropriate */
+static inline bool __hyp_text __hyp_handle_fpsimd(struct kvm_vcpu *vcpu)
+{
+ bool vhe, sve_guest, sve_host;
+ u8 hsr_ec;
+
+ if (!system_supports_fpsimd())
+ return false;
+
+ if (system_supports_sve()) {
+ sve_guest = vcpu_has_sve(vcpu);
+ sve_host = vcpu->arch.flags & KVM_ARM64_HOST_SVE_IN_USE;
+ vhe = true;
+ } else {
+ sve_guest = false;
+ sve_host = false;
+ vhe = has_vhe();
+ }
+
+ hsr_ec = kvm_vcpu_trap_get_class(vcpu);
+ if (hsr_ec != ESR_ELx_EC_FP_ASIMD &&
+ hsr_ec != ESR_ELx_EC_SVE)
+ return false;
+
+ /* Don't handle SVE traps for non-SVE vcpus here: */
+ if (!sve_guest)
+ if (hsr_ec != ESR_ELx_EC_FP_ASIMD)
+ return false;
+
+ /* Valid trap. Switch the context: */
+
+ if (vhe) {
+ u64 reg = read_sysreg(cpacr_el1) | CPACR_EL1_FPEN;
+
+ if (sve_guest)
+ reg |= CPACR_EL1_ZEN;
+
+ write_sysreg(reg, cpacr_el1);
+ } else {
+ write_sysreg(read_sysreg(cptr_el2) & ~(u64)CPTR_EL2_TFP,
+ cptr_el2);
+ }
+
+ isb();
+
+ if (vcpu->arch.flags & KVM_ARM64_FP_HOST) {
+ /*
+ * In the SVE case, VHE is assumed: it is enforced by
+ * Kconfig and kvm_arch_init().
+ */
+ if (sve_host) {
+ struct thread_struct *thread = container_of(
+ vcpu->arch.host_fpsimd_state,
+ struct thread_struct, uw.fpsimd_state);
+
+ sve_save_state(sve_pffr(thread),
+ &vcpu->arch.host_fpsimd_state->fpsr);
+ } else {
+ __fpsimd_save_state(vcpu->arch.host_fpsimd_state);
+ }
+
+ vcpu->arch.flags &= ~KVM_ARM64_FP_HOST;
+ }
+
+ if (sve_guest) {
+ sve_load_state(vcpu_sve_pffr(vcpu),
+ &vcpu->arch.ctxt.gp_regs.fp_regs.fpsr,
+ sve_vq_from_vl(vcpu->arch.sve_max_vl) - 1);
+ write_sysreg_s(vcpu->arch.ctxt.sys_regs[ZCR_EL1], SYS_ZCR_EL12);
+ } else {
+ __fpsimd_restore_state(&vcpu->arch.ctxt.gp_regs.fp_regs);
+ }
+
+ /* Skip restoring fpexc32 for AArch64 guests */
+ if (!(read_sysreg(hcr_el2) & HCR_RW))
+ write_sysreg(vcpu->arch.ctxt.sys_regs[FPEXC32_EL2],
+ fpexc32_el2);
+
+ vcpu->arch.flags |= KVM_ARM64_FP_ENABLED;
+
+ return true;
+}
+
+static inline bool __hyp_text handle_tx2_tvm(struct kvm_vcpu *vcpu)
+{
+ u32 sysreg = esr_sys64_to_sysreg(kvm_vcpu_get_hsr(vcpu));
+ int rt = kvm_vcpu_sys_get_rt(vcpu);
+ u64 val = vcpu_get_reg(vcpu, rt);
+
+ /*
+ * The normal sysreg handling code expects to see the traps,
+ * let's not do anything here.
+ */
+ if (vcpu->arch.hcr_el2 & HCR_TVM)
+ return false;
+
+ switch (sysreg) {
+ case SYS_SCTLR_EL1:
+ write_sysreg_el1(val, SYS_SCTLR);
+ break;
+ case SYS_TTBR0_EL1:
+ write_sysreg_el1(val, SYS_TTBR0);
+ break;
+ case SYS_TTBR1_EL1:
+ write_sysreg_el1(val, SYS_TTBR1);
+ break;
+ case SYS_TCR_EL1:
+ write_sysreg_el1(val, SYS_TCR);
+ break;
+ case SYS_ESR_EL1:
+ write_sysreg_el1(val, SYS_ESR);
+ break;
+ case SYS_FAR_EL1:
+ write_sysreg_el1(val, SYS_FAR);
+ break;
+ case SYS_AFSR0_EL1:
+ write_sysreg_el1(val, SYS_AFSR0);
+ break;
+ case SYS_AFSR1_EL1:
+ write_sysreg_el1(val, SYS_AFSR1);
+ break;
+ case SYS_MAIR_EL1:
+ write_sysreg_el1(val, SYS_MAIR);
+ break;
+ case SYS_AMAIR_EL1:
+ write_sysreg_el1(val, SYS_AMAIR);
+ break;
+ case SYS_CONTEXTIDR_EL1:
+ write_sysreg_el1(val, SYS_CONTEXTIDR);
+ break;
+ default:
+ return false;
+ }
+
+ __kvm_skip_instr(vcpu);
+ return true;
+}
+
+/*
+ * Return true when we were able to fixup the guest exit and should return to
+ * the guest, false when we should restore the host state and return to the
+ * main run loop.
+ */
+static inline bool __hyp_text
+fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
+{
+ if (ARM_EXCEPTION_CODE(*exit_code) != ARM_EXCEPTION_IRQ)
+ vcpu->arch.fault.esr_el2 = read_sysreg_el2(SYS_ESR);
+
+ /*
+ * We're using the raw exception code in order to only process
+ * the trap if no SError is pending. We will come back to the
+ * same PC once the SError has been injected, and replay the
+ * trapping instruction.
+ */
+ if (*exit_code != ARM_EXCEPTION_TRAP)
+ goto exit;
+
+ if (cpus_have_final_cap(ARM64_WORKAROUND_CAVIUM_TX2_219_TVM) &&
+ kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_SYS64 &&
+ handle_tx2_tvm(vcpu))
+ return true;
+
+ /*
+ * We trap the first access to the FP/SIMD to save the host context
+ * and restore the guest context lazily.
+ * If FP/SIMD is not implemented, handle the trap and inject an
+ * undefined instruction exception to the guest.
+ * Similarly for trapped SVE accesses.
+ */
+ if (__hyp_handle_fpsimd(vcpu))
+ return true;
+
+ if (!__populate_fault_info(vcpu))
+ return true;
+
+ if (static_branch_unlikely(&vgic_v2_cpuif_trap)) {
+ bool valid;
+
+ valid = kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_DABT_LOW &&
+ kvm_vcpu_trap_get_fault_type(vcpu) == FSC_FAULT &&
+ kvm_vcpu_dabt_isvalid(vcpu) &&
+ !kvm_vcpu_dabt_isextabt(vcpu) &&
+ !kvm_vcpu_dabt_iss1tw(vcpu);
+
+ if (valid) {
+ int ret = __vgic_v2_perform_cpuif_access(vcpu);
+
+ if (ret == 1)
+ return true;
+
+ /* Promote an illegal access to an SError.*/
+ if (ret == -1)
+ *exit_code = ARM_EXCEPTION_EL1_SERROR;
+
+ goto exit;
+ }
+ }
+
+ if (static_branch_unlikely(&vgic_v3_cpuif_trap) &&
+ (kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_SYS64 ||
+ kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_CP15_32)) {
+ int ret = __vgic_v3_perform_cpuif_access(vcpu);
+
+ if (ret == 1)
+ return true;
+ }
+
+exit:
+ /* Return to the host kernel and handle the exit */
+ return false;
+}
+
+static inline bool __hyp_text __needs_ssbd_off(struct kvm_vcpu *vcpu)
+{
+ if (!cpus_have_final_cap(ARM64_SSBD))
+ return false;
+
+ return !(vcpu->arch.workaround_flags & VCPU_WORKAROUND_2_FLAG);
+}
+
+static inline void __hyp_text
+__set_guest_arch_workaround_state(struct kvm_vcpu *vcpu)
+{
+#ifdef CONFIG_ARM64_SSBD
+ /*
+ * The host runs with the workaround always present. If the
+ * guest wants it disabled, so be it...
+ */
+ if (__needs_ssbd_off(vcpu) &&
+ __hyp_this_cpu_read(arm64_ssbd_callback_required))
+ arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 0, NULL);
+#endif
+}
+
+static inline void __hyp_text
+__set_host_arch_workaround_state(struct kvm_vcpu *vcpu)
+{
+#ifdef CONFIG_ARM64_SSBD
+ /*
+ * If the guest has disabled the workaround, bring it back on.
+ */
+ if (__needs_ssbd_off(vcpu) &&
+ __hyp_this_cpu_read(arm64_ssbd_callback_required))
+ arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 1, NULL);
+#endif
+}
diff --git a/arch/arm64/kvm/hyp/sysreg-sr.c b/arch/arm64/kvm/hyp/sysreg-sr.c
index 75b1925763f1..7a261ace2405 100644
--- a/arch/arm64/kvm/hyp/sysreg-sr.c
+++ b/arch/arm64/kvm/hyp/sysreg-sr.c
@@ -125,7 +125,7 @@ static void __hyp_text __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt)
/*
* Must only be done for guest registers, hence the context
* test. We're coming from the host, so SCTLR.M is already
- * set. Pairs with __activate_traps_nvhe().
+ * set. Pairs with nVHE's __activate_traps().
*/
write_sysreg_el1((ctxt->sys_regs[TCR_EL1] |
TCR_EPD1_MASK | TCR_EPD0_MASK),
@@ -153,7 +153,7 @@ static void __hyp_text __sysreg_restore_el1_state(struct kvm_cpu_context *ctxt)
ctxt->__hyp_running_vcpu) {
/*
* Must only be done for host registers, hence the context
- * test. Pairs with __deactivate_traps_nvhe().
+ * test. Pairs with nVHE's __deactivate_traps().
*/
isb();
/*
--
2.26.1
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