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linux/arch/arm64/kvm/hyp/vhe/switch.c
Mark Rutland 59419f1004 KVM: arm64: Eagerly switch ZCR_EL{1,2}
In non-protected KVM modes, while the guest FPSIMD/SVE/SME state is live on the
CPU, the host's active SVE VL may differ from the guest's maximum SVE VL:

* For VHE hosts, when a VM uses NV, ZCR_EL2 contains a value constrained
  by the guest hypervisor, which may be less than or equal to that
  guest's maximum VL.

  Note: in this case the value of ZCR_EL1 is immaterial due to E2H.

* For nVHE/hVHE hosts, ZCR_EL1 contains a value written by the guest,
  which may be less than or greater than the guest's maximum VL.

  Note: in this case hyp code traps host SVE usage and lazily restores
  ZCR_EL2 to the host's maximum VL, which may be greater than the
  guest's maximum VL.

This can be the case between exiting a guest and kvm_arch_vcpu_put_fp().
If a softirq is taken during this period and the softirq handler tries
to use kernel-mode NEON, then the kernel will fail to save the guest's
FPSIMD/SVE state, and will pend a SIGKILL for the current thread.

This happens because kvm_arch_vcpu_ctxsync_fp() binds the guest's live
FPSIMD/SVE state with the guest's maximum SVE VL, and
fpsimd_save_user_state() verifies that the live SVE VL is as expected
before attempting to save the register state:

| if (WARN_ON(sve_get_vl() != vl)) {
|         force_signal_inject(SIGKILL, SI_KERNEL, 0, 0);
|         return;
| }

Fix this and make this a bit easier to reason about by always eagerly
switching ZCR_EL{1,2} at hyp during guest<->host transitions. With this
happening, there's no need to trap host SVE usage, and the nVHE/nVHE
__deactivate_cptr_traps() logic can be simplified to enable host access
to all present FPSIMD/SVE/SME features.

In protected nVHE/hVHE modes, the host's state is always saved/restored
by hyp, and the guest's state is saved prior to exit to the host, so
from the host's PoV the guest never has live FPSIMD/SVE/SME state, and
the host's ZCR_EL1 is never clobbered by hyp.

Fixes: 8c8010d69c ("KVM: arm64: Save/restore SVE state for nVHE")
Fixes: 2e3cf82063 ("KVM: arm64: nv: Ensure correct VL is loaded before saving SVE state")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Tested-by: Mark Brown <broonie@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Fuad Tabba <tabba@google.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20250210195226.1215254-9-mark.rutland@arm.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
2025-02-13 17:55:06 +00:00

685 lines
17 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2015 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*/
#include <hyp/switch.h>
#include <linux/arm-smccc.h>
#include <linux/kvm_host.h>
#include <linux/types.h>
#include <linux/jump_label.h>
#include <linux/percpu.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 <asm/vectors.h>
/* VHE specific context */
DEFINE_PER_CPU(struct kvm_host_data, kvm_host_data);
DEFINE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt);
DEFINE_PER_CPU(unsigned long, kvm_hyp_vector);
/*
* HCR_EL2 bits that the NV guest can freely change (no RES0/RES1
* semantics, irrespective of the configuration), but that cannot be
* applied to the actual HW as things would otherwise break badly.
*
* - TGE: we want the guest to use EL1, which is incompatible with
* this bit being set
*
* - API/APK: they are already accounted for by vcpu_load(), and can
* only take effect across a load/put cycle (such as ERET)
*/
#define NV_HCR_GUEST_EXCLUDE (HCR_TGE | HCR_API | HCR_APK)
static u64 __compute_hcr(struct kvm_vcpu *vcpu)
{
u64 hcr = vcpu->arch.hcr_el2;
if (!vcpu_has_nv(vcpu))
return hcr;
if (is_hyp_ctxt(vcpu)) {
hcr |= HCR_NV | HCR_NV2 | HCR_AT | HCR_TTLB;
if (!vcpu_el2_e2h_is_set(vcpu))
hcr |= HCR_NV1;
write_sysreg_s(vcpu->arch.ctxt.vncr_array, SYS_VNCR_EL2);
}
return hcr | (__vcpu_sys_reg(vcpu, HCR_EL2) & ~NV_HCR_GUEST_EXCLUDE);
}
static void __activate_cptr_traps(struct kvm_vcpu *vcpu)
{
u64 cptr;
/*
* With VHE (HCR.E2H == 1), accesses to CPACR_EL1 are routed to
* CPTR_EL2. In general, CPACR_EL1 has the same layout as CPTR_EL2,
* except for some missing controls, such as TAM.
* In this case, CPTR_EL2.TAM has the same position with or without
* VHE (HCR.E2H == 1) which allows us to use here the CPTR_EL2.TAM
* shift value for trapping the AMU accesses.
*/
u64 val = CPACR_EL1_TTA | CPTR_EL2_TAM;
if (guest_owns_fp_regs()) {
val |= CPACR_EL1_FPEN;
if (vcpu_has_sve(vcpu))
val |= CPACR_EL1_ZEN;
} else {
__activate_traps_fpsimd32(vcpu);
}
if (!vcpu_has_nv(vcpu))
goto write;
/*
* The architecture is a bit crap (what a surprise): an EL2 guest
* writing to CPTR_EL2 via CPACR_EL1 can't set any of TCPAC or TTA,
* as they are RES0 in the guest's view. To work around it, trap the
* sucker using the very same bit it can't set...
*/
if (vcpu_el2_e2h_is_set(vcpu) && is_hyp_ctxt(vcpu))
val |= CPTR_EL2_TCPAC;
/*
* Layer the guest hypervisor's trap configuration on top of our own if
* we're in a nested context.
*/
if (is_hyp_ctxt(vcpu))
goto write;
cptr = vcpu_sanitised_cptr_el2(vcpu);
/*
* Pay attention, there's some interesting detail here.
*
* The CPTR_EL2.xEN fields are 2 bits wide, although there are only two
* meaningful trap states when HCR_EL2.TGE = 0 (running a nested guest):
*
* - CPTR_EL2.xEN = x0, traps are enabled
* - CPTR_EL2.xEN = x1, traps are disabled
*
* In other words, bit[0] determines if guest accesses trap or not. In
* the interest of simplicity, clear the entire field if the guest
* hypervisor has traps enabled to dispel any illusion of something more
* complicated taking place.
*/
if (!(SYS_FIELD_GET(CPACR_EL1, FPEN, cptr) & BIT(0)))
val &= ~CPACR_EL1_FPEN;
if (!(SYS_FIELD_GET(CPACR_EL1, ZEN, cptr) & BIT(0)))
val &= ~CPACR_EL1_ZEN;
if (kvm_has_feat(vcpu->kvm, ID_AA64MMFR3_EL1, S2POE, IMP))
val |= cptr & CPACR_EL1_E0POE;
val |= cptr & CPTR_EL2_TCPAC;
write:
write_sysreg(val, cpacr_el1);
}
static void __deactivate_cptr_traps(struct kvm_vcpu *vcpu)
{
u64 val = CPACR_EL1_FPEN | CPACR_EL1_ZEN_EL1EN;
if (cpus_have_final_cap(ARM64_SME))
val |= CPACR_EL1_SMEN_EL1EN;
write_sysreg(val, cpacr_el1);
}
static void __activate_traps(struct kvm_vcpu *vcpu)
{
u64 val;
___activate_traps(vcpu, __compute_hcr(vcpu));
if (has_cntpoff()) {
struct timer_map map;
get_timer_map(vcpu, &map);
/*
* We're entrering the guest. Reload the correct
* values from memory now that TGE is clear.
*/
if (map.direct_ptimer == vcpu_ptimer(vcpu))
val = __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0);
if (map.direct_ptimer == vcpu_hptimer(vcpu))
val = __vcpu_sys_reg(vcpu, CNTHP_CVAL_EL2);
if (map.direct_ptimer) {
write_sysreg_el0(val, SYS_CNTP_CVAL);
isb();
}
}
__activate_cptr_traps(vcpu);
write_sysreg(__this_cpu_read(kvm_hyp_vector), vbar_el1);
}
NOKPROBE_SYMBOL(__activate_traps);
static void __deactivate_traps(struct kvm_vcpu *vcpu)
{
const char *host_vectors = vectors;
___deactivate_traps(vcpu);
write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2);
if (has_cntpoff()) {
struct timer_map map;
u64 val, offset;
get_timer_map(vcpu, &map);
/*
* We're exiting the guest. Save the latest CVAL value
* to memory and apply the offset now that TGE is set.
*/
val = read_sysreg_el0(SYS_CNTP_CVAL);
if (map.direct_ptimer == vcpu_ptimer(vcpu))
__vcpu_sys_reg(vcpu, CNTP_CVAL_EL0) = val;
if (map.direct_ptimer == vcpu_hptimer(vcpu))
__vcpu_sys_reg(vcpu, CNTHP_CVAL_EL2) = val;
offset = read_sysreg_s(SYS_CNTPOFF_EL2);
if (map.direct_ptimer && offset) {
write_sysreg_el0(val + offset, SYS_CNTP_CVAL);
isb();
}
}
/*
* ARM errata 1165522 and 1530923 require the actual execution of the
* above before we can switch to the EL2/EL0 translation regime used by
* the host.
*/
asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_SPECULATIVE_AT));
__deactivate_cptr_traps(vcpu);
if (!arm64_kernel_unmapped_at_el0())
host_vectors = __this_cpu_read(this_cpu_vector);
write_sysreg(host_vectors, vbar_el1);
}
NOKPROBE_SYMBOL(__deactivate_traps);
/*
* Disable IRQs in __vcpu_{load,put}_{activate,deactivate}_traps() to
* prevent a race condition between context switching of PMUSERENR_EL0
* in __{activate,deactivate}_traps_common() and IPIs that attempts to
* update PMUSERENR_EL0. See also kvm_set_pmuserenr().
*/
static void __vcpu_load_activate_traps(struct kvm_vcpu *vcpu)
{
unsigned long flags;
local_irq_save(flags);
__activate_traps_common(vcpu);
local_irq_restore(flags);
}
static void __vcpu_put_deactivate_traps(struct kvm_vcpu *vcpu)
{
unsigned long flags;
local_irq_save(flags);
__deactivate_traps_common(vcpu);
local_irq_restore(flags);
}
void kvm_vcpu_load_vhe(struct kvm_vcpu *vcpu)
{
host_data_ptr(host_ctxt)->__hyp_running_vcpu = vcpu;
__vcpu_load_switch_sysregs(vcpu);
__vcpu_load_activate_traps(vcpu);
__load_stage2(vcpu->arch.hw_mmu, vcpu->arch.hw_mmu->arch);
}
void kvm_vcpu_put_vhe(struct kvm_vcpu *vcpu)
{
__vcpu_put_deactivate_traps(vcpu);
__vcpu_put_switch_sysregs(vcpu);
host_data_ptr(host_ctxt)->__hyp_running_vcpu = NULL;
}
static u64 compute_emulated_cntx_ctl_el0(struct kvm_vcpu *vcpu,
enum vcpu_sysreg reg)
{
unsigned long ctl;
u64 cval, cnt;
bool stat;
switch (reg) {
case CNTP_CTL_EL0:
cval = __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0);
ctl = __vcpu_sys_reg(vcpu, CNTP_CTL_EL0);
cnt = compute_counter_value(vcpu_ptimer(vcpu));
break;
case CNTV_CTL_EL0:
cval = __vcpu_sys_reg(vcpu, CNTV_CVAL_EL0);
ctl = __vcpu_sys_reg(vcpu, CNTV_CTL_EL0);
cnt = compute_counter_value(vcpu_vtimer(vcpu));
break;
default:
BUG();
}
stat = cval <= cnt;
__assign_bit(__ffs(ARCH_TIMER_CTRL_IT_STAT), &ctl, stat);
return ctl;
}
static bool kvm_hyp_handle_timer(struct kvm_vcpu *vcpu, u64 *exit_code)
{
u64 esr, val;
/*
* Having FEAT_ECV allows for a better quality of timer emulation.
* However, this comes at a huge cost in terms of traps. Try and
* satisfy the reads from guest's hypervisor context without
* returning to the kernel if we can.
*/
if (!is_hyp_ctxt(vcpu))
return false;
esr = kvm_vcpu_get_esr(vcpu);
if ((esr & ESR_ELx_SYS64_ISS_DIR_MASK) != ESR_ELx_SYS64_ISS_DIR_READ)
return false;
switch (esr_sys64_to_sysreg(esr)) {
case SYS_CNTP_CTL_EL02:
val = compute_emulated_cntx_ctl_el0(vcpu, CNTP_CTL_EL0);
break;
case SYS_CNTP_CTL_EL0:
if (vcpu_el2_e2h_is_set(vcpu))
val = read_sysreg_el0(SYS_CNTP_CTL);
else
val = compute_emulated_cntx_ctl_el0(vcpu, CNTP_CTL_EL0);
break;
case SYS_CNTP_CVAL_EL02:
val = __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0);
break;
case SYS_CNTP_CVAL_EL0:
if (vcpu_el2_e2h_is_set(vcpu)) {
val = read_sysreg_el0(SYS_CNTP_CVAL);
if (!has_cntpoff())
val -= timer_get_offset(vcpu_hptimer(vcpu));
} else {
val = __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0);
}
break;
case SYS_CNTPCT_EL0:
case SYS_CNTPCTSS_EL0:
val = compute_counter_value(vcpu_hptimer(vcpu));
break;
case SYS_CNTV_CTL_EL02:
val = compute_emulated_cntx_ctl_el0(vcpu, CNTV_CTL_EL0);
break;
case SYS_CNTV_CTL_EL0:
if (vcpu_el2_e2h_is_set(vcpu))
val = read_sysreg_el0(SYS_CNTV_CTL);
else
val = compute_emulated_cntx_ctl_el0(vcpu, CNTV_CTL_EL0);
break;
case SYS_CNTV_CVAL_EL02:
val = __vcpu_sys_reg(vcpu, CNTV_CVAL_EL0);
break;
case SYS_CNTV_CVAL_EL0:
if (vcpu_el2_e2h_is_set(vcpu))
val = read_sysreg_el0(SYS_CNTV_CVAL);
else
val = __vcpu_sys_reg(vcpu, CNTV_CVAL_EL0);
break;
case SYS_CNTVCT_EL0:
case SYS_CNTVCTSS_EL0:
val = compute_counter_value(vcpu_hvtimer(vcpu));
break;
default:
return false;
}
vcpu_set_reg(vcpu, kvm_vcpu_sys_get_rt(vcpu), val);
__kvm_skip_instr(vcpu);
return true;
}
static bool kvm_hyp_handle_eret(struct kvm_vcpu *vcpu, u64 *exit_code)
{
u64 esr = kvm_vcpu_get_esr(vcpu);
u64 spsr, elr, mode;
/*
* Going through the whole put/load motions is a waste of time
* if this is a VHE guest hypervisor returning to its own
* userspace, or the hypervisor performing a local exception
* return. No need to save/restore registers, no need to
* switch S2 MMU. Just do the canonical ERET.
*
* Unless the trap has to be forwarded further down the line,
* of course...
*/
if ((__vcpu_sys_reg(vcpu, HCR_EL2) & HCR_NV) ||
(__vcpu_sys_reg(vcpu, HFGITR_EL2) & HFGITR_EL2_ERET))
return false;
spsr = read_sysreg_el1(SYS_SPSR);
mode = spsr & (PSR_MODE_MASK | PSR_MODE32_BIT);
switch (mode) {
case PSR_MODE_EL0t:
if (!(vcpu_el2_e2h_is_set(vcpu) && vcpu_el2_tge_is_set(vcpu)))
return false;
break;
case PSR_MODE_EL2t:
mode = PSR_MODE_EL1t;
break;
case PSR_MODE_EL2h:
mode = PSR_MODE_EL1h;
break;
default:
return false;
}
/* If ERETAx fails, take the slow path */
if (esr_iss_is_eretax(esr)) {
if (!(vcpu_has_ptrauth(vcpu) && kvm_auth_eretax(vcpu, &elr)))
return false;
} else {
elr = read_sysreg_el1(SYS_ELR);
}
spsr = (spsr & ~(PSR_MODE_MASK | PSR_MODE32_BIT)) | mode;
write_sysreg_el2(spsr, SYS_SPSR);
write_sysreg_el2(elr, SYS_ELR);
return true;
}
static bool kvm_hyp_handle_tlbi_el2(struct kvm_vcpu *vcpu, u64 *exit_code)
{
int ret = -EINVAL;
u32 instr;
u64 val;
/*
* Ideally, we would never trap on EL2 S1 TLB invalidations using
* the EL1 instructions when the guest's HCR_EL2.{E2H,TGE}=={1,1}.
* But "thanks" to FEAT_NV2, we don't trap writes to HCR_EL2,
* meaning that we can't track changes to the virtual TGE bit. So we
* have to leave HCR_EL2.TTLB set on the host. Oopsie...
*
* Try and handle these invalidation as quickly as possible, without
* fully exiting. Note that we don't need to consider any forwarding
* here, as having E2H+TGE set is the very definition of being
* InHost.
*
* For the lesser hypervisors out there that have failed to get on
* with the VHE program, we can also handle the nVHE style of EL2
* invalidation.
*/
if (!(is_hyp_ctxt(vcpu)))
return false;
instr = esr_sys64_to_sysreg(kvm_vcpu_get_esr(vcpu));
val = vcpu_get_reg(vcpu, kvm_vcpu_sys_get_rt(vcpu));
if ((kvm_supported_tlbi_s1e1_op(vcpu, instr) &&
vcpu_el2_e2h_is_set(vcpu) && vcpu_el2_tge_is_set(vcpu)) ||
kvm_supported_tlbi_s1e2_op (vcpu, instr))
ret = __kvm_tlbi_s1e2(NULL, val, instr);
if (ret)
return false;
__kvm_skip_instr(vcpu);
return true;
}
static bool kvm_hyp_handle_cpacr_el1(struct kvm_vcpu *vcpu, u64 *exit_code)
{
u64 esr = kvm_vcpu_get_esr(vcpu);
int rt;
if (!is_hyp_ctxt(vcpu) || esr_sys64_to_sysreg(esr) != SYS_CPACR_EL1)
return false;
rt = kvm_vcpu_sys_get_rt(vcpu);
if ((esr & ESR_ELx_SYS64_ISS_DIR_MASK) == ESR_ELx_SYS64_ISS_DIR_READ) {
vcpu_set_reg(vcpu, rt, __vcpu_sys_reg(vcpu, CPTR_EL2));
} else {
vcpu_write_sys_reg(vcpu, vcpu_get_reg(vcpu, rt), CPTR_EL2);
__activate_cptr_traps(vcpu);
}
__kvm_skip_instr(vcpu);
return true;
}
static bool kvm_hyp_handle_zcr_el2(struct kvm_vcpu *vcpu, u64 *exit_code)
{
u32 sysreg = esr_sys64_to_sysreg(kvm_vcpu_get_esr(vcpu));
if (!vcpu_has_nv(vcpu))
return false;
if (sysreg != SYS_ZCR_EL2)
return false;
if (guest_owns_fp_regs())
return false;
/*
* ZCR_EL2 traps are handled in the slow path, with the expectation
* that the guest's FP context has already been loaded onto the CPU.
*
* Load the guest's FP context and unconditionally forward to the
* slow path for handling (i.e. return false).
*/
kvm_hyp_handle_fpsimd(vcpu, exit_code);
return false;
}
static bool kvm_hyp_handle_sysreg_vhe(struct kvm_vcpu *vcpu, u64 *exit_code)
{
if (kvm_hyp_handle_tlbi_el2(vcpu, exit_code))
return true;
if (kvm_hyp_handle_timer(vcpu, exit_code))
return true;
if (kvm_hyp_handle_cpacr_el1(vcpu, exit_code))
return true;
if (kvm_hyp_handle_zcr_el2(vcpu, exit_code))
return true;
return kvm_hyp_handle_sysreg(vcpu, exit_code);
}
static const exit_handler_fn hyp_exit_handlers[] = {
[0 ... ESR_ELx_EC_MAX] = NULL,
[ESR_ELx_EC_CP15_32] = kvm_hyp_handle_cp15_32,
[ESR_ELx_EC_SYS64] = kvm_hyp_handle_sysreg_vhe,
[ESR_ELx_EC_SVE] = kvm_hyp_handle_fpsimd,
[ESR_ELx_EC_FP_ASIMD] = kvm_hyp_handle_fpsimd,
[ESR_ELx_EC_IABT_LOW] = kvm_hyp_handle_iabt_low,
[ESR_ELx_EC_DABT_LOW] = kvm_hyp_handle_dabt_low,
[ESR_ELx_EC_WATCHPT_LOW] = kvm_hyp_handle_watchpt_low,
[ESR_ELx_EC_ERET] = kvm_hyp_handle_eret,
[ESR_ELx_EC_MOPS] = kvm_hyp_handle_mops,
};
static inline bool fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
{
synchronize_vcpu_pstate(vcpu, exit_code);
/*
* If we were in HYP context on entry, adjust the PSTATE view
* so that the usual helpers work correctly.
*/
if (vcpu_has_nv(vcpu) && (read_sysreg(hcr_el2) & HCR_NV)) {
u64 mode = *vcpu_cpsr(vcpu) & (PSR_MODE_MASK | PSR_MODE32_BIT);
switch (mode) {
case PSR_MODE_EL1t:
mode = PSR_MODE_EL2t;
break;
case PSR_MODE_EL1h:
mode = PSR_MODE_EL2h;
break;
}
*vcpu_cpsr(vcpu) &= ~(PSR_MODE_MASK | PSR_MODE32_BIT);
*vcpu_cpsr(vcpu) |= mode;
}
return __fixup_guest_exit(vcpu, exit_code, hyp_exit_handlers);
}
/* Switch to the guest for VHE systems running in EL2 */
static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu)
{
struct kvm_cpu_context *host_ctxt;
struct kvm_cpu_context *guest_ctxt;
u64 exit_code;
host_ctxt = host_data_ptr(host_ctxt);
guest_ctxt = &vcpu->arch.ctxt;
sysreg_save_host_state_vhe(host_ctxt);
fpsimd_lazy_switch_to_guest(vcpu);
/*
* Note that ARM erratum 1165522 requires us to configure both stage 1
* and stage 2 translation for the guest context before we clear
* HCR_EL2.TGE. The stage 1 and stage 2 guest context has already been
* loaded on the CPU in kvm_vcpu_load_vhe().
*/
__activate_traps(vcpu);
__kvm_adjust_pc(vcpu);
sysreg_restore_guest_state_vhe(guest_ctxt);
__debug_switch_to_guest(vcpu);
do {
/* Jump in the fire! */
exit_code = __guest_enter(vcpu);
/* And we're baaack! */
} while (fixup_guest_exit(vcpu, &exit_code));
sysreg_save_guest_state_vhe(guest_ctxt);
__deactivate_traps(vcpu);
fpsimd_lazy_switch_to_host(vcpu);
sysreg_restore_host_state_vhe(host_ctxt);
if (guest_owns_fp_regs())
__fpsimd_save_fpexc32(vcpu);
__debug_switch_to_host(vcpu);
return exit_code;
}
NOKPROBE_SYMBOL(__kvm_vcpu_run_vhe);
int __kvm_vcpu_run(struct kvm_vcpu *vcpu)
{
int ret;
local_daif_mask();
/*
* 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.
*
* local_daif_mask() already sets GIC_PRIO_PSR_I_SET, we just need a
* dsb to ensure the redistributor is forwards EL2 IRQs to the CPU.
*/
pmr_sync();
ret = __kvm_vcpu_run_vhe(vcpu);
/*
* local_daif_restore() takes care to properly restore PSTATE.DAIF
* and the GIC PMR if the host is using IRQ priorities.
*/
local_daif_restore(DAIF_PROCCTX_NOIRQ);
/*
* When we exit from the guest we change a number of CPU configuration
* parameters, such as traps. We rely on the isb() in kvm_call_hyp*()
* to make sure these changes take effect before running the host or
* additional guests.
*/
return ret;
}
static void __noreturn __hyp_call_panic(u64 spsr, u64 elr, u64 par)
{
struct kvm_cpu_context *host_ctxt;
struct kvm_vcpu *vcpu;
host_ctxt = host_data_ptr(host_ctxt);
vcpu = host_ctxt->__hyp_running_vcpu;
__deactivate_traps(vcpu);
sysreg_restore_host_state_vhe(host_ctxt);
panic("HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n",
spsr, elr,
read_sysreg_el2(SYS_ESR), read_sysreg_el2(SYS_FAR),
read_sysreg(hpfar_el2), par, vcpu);
}
NOKPROBE_SYMBOL(__hyp_call_panic);
void __noreturn hyp_panic(void)
{
u64 spsr = read_sysreg_el2(SYS_SPSR);
u64 elr = read_sysreg_el2(SYS_ELR);
u64 par = read_sysreg_par();
__hyp_call_panic(spsr, elr, par);
}
asmlinkage void kvm_unexpected_el2_exception(void)
{
__kvm_unexpected_el2_exception();
}