qemu/target/arm/kvm32.c
Peter Maydell 942f99c825 Revert "arm: Allow system registers for KVM guests to be changed by QEMU code"
This reverts commit 823e1b3818,
which introduces a regression running EDK2 guest firmware
under KVM:

error: kvm run failed Function not implemented
 PC=000000013f5a6208 X00=00000000404003c4 X01=000000000000003a
X02=0000000000000000 X03=00000000404003c4 X04=0000000000000000
X05=0000000096000046 X06=000000013d2ef270 X07=000000013e3d1710
X08=09010755ffaf8ba8 X09=ffaf8b9cfeeb5468 X10=feeb546409010756
X11=09010757ffaf8b90 X12=feeb50680903068b X13=090306a1ffaf8bc0
X14=0000000000000000 X15=0000000000000000 X16=000000013f872da0
X17=00000000ffffa6ab X18=0000000000000000 X19=000000013f5a92d0
X20=000000013f5a7a78 X21=000000000000003a X22=000000013f5a7ab2
X23=000000013f5a92e8 X24=000000013f631090 X25=0000000000000010
X26=0000000000000100 X27=000000013f89501b X28=000000013e3d14e0
X29=000000013e3d12a0 X30=000000013f5a2518  SP=000000013b7be0b0
PSTATE=404003c4 -Z-- EL1t

with
[ 3507.926571] kvm [35042]: load/store instruction decoding not implemented
in the host dmesg.

Revert the change for the moment until we can investigate the
cause of the regression.

Reported-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-02-28 11:03:05 +00:00

548 lines
17 KiB
C

/*
* ARM implementation of KVM hooks, 32 bit specific code.
*
* Copyright Christoffer Dall 2009-2010
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#include "qemu/osdep.h"
#include <sys/ioctl.h>
#include <linux/kvm.h>
#include "qemu-common.h"
#include "cpu.h"
#include "qemu/timer.h"
#include "sysemu/sysemu.h"
#include "sysemu/kvm.h"
#include "kvm_arm.h"
#include "internals.h"
#include "hw/arm/arm.h"
#include "qemu/log.h"
static inline void set_feature(uint64_t *features, int feature)
{
*features |= 1ULL << feature;
}
static int read_sys_reg32(int fd, uint32_t *pret, uint64_t id)
{
struct kvm_one_reg idreg = { .id = id, .addr = (uintptr_t)pret };
assert((id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32);
return ioctl(fd, KVM_GET_ONE_REG, &idreg);
}
bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)
{
/* Identify the feature bits corresponding to the host CPU, and
* fill out the ARMHostCPUClass fields accordingly. To do this
* we have to create a scratch VM, create a single CPU inside it,
* and then query that CPU for the relevant ID registers.
*/
int err = 0, fdarray[3];
uint32_t midr, id_pfr0;
uint64_t features = 0;
/* Old kernels may not know about the PREFERRED_TARGET ioctl: however
* we know these will only support creating one kind of guest CPU,
* which is its preferred CPU type.
*/
static const uint32_t cpus_to_try[] = {
QEMU_KVM_ARM_TARGET_CORTEX_A15,
QEMU_KVM_ARM_TARGET_NONE
};
struct kvm_vcpu_init init;
if (!kvm_arm_create_scratch_host_vcpu(cpus_to_try, fdarray, &init)) {
return false;
}
ahcf->target = init.target;
/* This is not strictly blessed by the device tree binding docs yet,
* but in practice the kernel does not care about this string so
* there is no point maintaining an KVM_ARM_TARGET_* -> string table.
*/
ahcf->dtb_compatible = "arm,arm-v7";
err |= read_sys_reg32(fdarray[2], &midr, ARM_CP15_REG32(0, 0, 0, 0));
err |= read_sys_reg32(fdarray[2], &id_pfr0, ARM_CP15_REG32(0, 0, 1, 0));
err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar0,
ARM_CP15_REG32(0, 0, 2, 0));
err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar1,
ARM_CP15_REG32(0, 0, 2, 1));
err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar2,
ARM_CP15_REG32(0, 0, 2, 2));
err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar3,
ARM_CP15_REG32(0, 0, 2, 3));
err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar4,
ARM_CP15_REG32(0, 0, 2, 4));
err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar5,
ARM_CP15_REG32(0, 0, 2, 5));
if (read_sys_reg32(fdarray[2], &ahcf->isar.id_isar6,
ARM_CP15_REG32(0, 0, 2, 7))) {
/*
* Older kernels don't support reading ID_ISAR6. This register was
* only introduced in ARMv8, so we can assume that it is zero on a
* CPU that a kernel this old is running on.
*/
ahcf->isar.id_isar6 = 0;
}
err |= read_sys_reg32(fdarray[2], &ahcf->isar.mvfr0,
KVM_REG_ARM | KVM_REG_SIZE_U32 |
KVM_REG_ARM_VFP | KVM_REG_ARM_VFP_MVFR0);
err |= read_sys_reg32(fdarray[2], &ahcf->isar.mvfr1,
KVM_REG_ARM | KVM_REG_SIZE_U32 |
KVM_REG_ARM_VFP | KVM_REG_ARM_VFP_MVFR1);
/*
* FIXME: There is not yet a way to read MVFR2.
* Fortunately there is not yet anything in there that affects migration.
*/
kvm_arm_destroy_scratch_host_vcpu(fdarray);
if (err < 0) {
return false;
}
/* Now we've retrieved all the register information we can
* set the feature bits based on the ID register fields.
* We can assume any KVM supporting CPU is at least a v7
* with VFPv3, virtualization extensions, and the generic
* timers; this in turn implies most of the other feature
* bits, but a few must be tested.
*/
set_feature(&features, ARM_FEATURE_V7VE);
set_feature(&features, ARM_FEATURE_VFP3);
set_feature(&features, ARM_FEATURE_GENERIC_TIMER);
if (extract32(id_pfr0, 12, 4) == 1) {
set_feature(&features, ARM_FEATURE_THUMB2EE);
}
if (extract32(ahcf->isar.mvfr1, 12, 4) == 1) {
set_feature(&features, ARM_FEATURE_NEON);
}
if (extract32(ahcf->isar.mvfr1, 28, 4) == 1) {
/* FMAC support implies VFPv4 */
set_feature(&features, ARM_FEATURE_VFP4);
}
ahcf->features = features;
return true;
}
bool kvm_arm_reg_syncs_via_cpreg_list(uint64_t regidx)
{
/* Return true if the regidx is a register we should synchronize
* via the cpreg_tuples array (ie is not a core reg we sync by
* hand in kvm_arch_get/put_registers())
*/
switch (regidx & KVM_REG_ARM_COPROC_MASK) {
case KVM_REG_ARM_CORE:
case KVM_REG_ARM_VFP:
return false;
default:
return true;
}
}
typedef struct CPRegStateLevel {
uint64_t regidx;
int level;
} CPRegStateLevel;
/* All coprocessor registers not listed in the following table are assumed to
* be of the level KVM_PUT_RUNTIME_STATE. If a register should be written less
* often, you must add it to this table with a state of either
* KVM_PUT_RESET_STATE or KVM_PUT_FULL_STATE.
*/
static const CPRegStateLevel non_runtime_cpregs[] = {
{ KVM_REG_ARM_TIMER_CNT, KVM_PUT_FULL_STATE },
};
int kvm_arm_cpreg_level(uint64_t regidx)
{
int i;
for (i = 0; i < ARRAY_SIZE(non_runtime_cpregs); i++) {
const CPRegStateLevel *l = &non_runtime_cpregs[i];
if (l->regidx == regidx) {
return l->level;
}
}
return KVM_PUT_RUNTIME_STATE;
}
#define ARM_CPU_ID_MPIDR 0, 0, 0, 5
int kvm_arch_init_vcpu(CPUState *cs)
{
int ret;
uint64_t v;
uint32_t mpidr;
struct kvm_one_reg r;
ARMCPU *cpu = ARM_CPU(cs);
if (cpu->kvm_target == QEMU_KVM_ARM_TARGET_NONE) {
fprintf(stderr, "KVM is not supported for this guest CPU type\n");
return -EINVAL;
}
/* Determine init features for this CPU */
memset(cpu->kvm_init_features, 0, sizeof(cpu->kvm_init_features));
if (cpu->start_powered_off) {
cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_POWER_OFF;
}
if (kvm_check_extension(cs->kvm_state, KVM_CAP_ARM_PSCI_0_2)) {
cpu->psci_version = 2;
cpu->kvm_init_features[0] |= 1 << KVM_ARM_VCPU_PSCI_0_2;
}
/* Do KVM_ARM_VCPU_INIT ioctl */
ret = kvm_arm_vcpu_init(cs);
if (ret) {
return ret;
}
/* Query the kernel to make sure it supports 32 VFP
* registers: QEMU's "cortex-a15" CPU is always a
* VFP-D32 core. The simplest way to do this is just
* to attempt to read register d31.
*/
r.id = KVM_REG_ARM | KVM_REG_SIZE_U64 | KVM_REG_ARM_VFP | 31;
r.addr = (uintptr_t)(&v);
ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r);
if (ret == -ENOENT) {
return -EINVAL;
}
/*
* When KVM is in use, PSCI is emulated in-kernel and not by qemu.
* Currently KVM has its own idea about MPIDR assignment, so we
* override our defaults with what we get from KVM.
*/
ret = kvm_get_one_reg(cs, ARM_CP15_REG32(ARM_CPU_ID_MPIDR), &mpidr);
if (ret) {
return ret;
}
cpu->mp_affinity = mpidr & ARM32_AFFINITY_MASK;
/* Check whether userspace can specify guest syndrome value */
kvm_arm_init_serror_injection(cs);
return kvm_arm_init_cpreg_list(cpu);
}
typedef struct Reg {
uint64_t id;
int offset;
} Reg;
#define COREREG(KERNELNAME, QEMUFIELD) \
{ \
KVM_REG_ARM | KVM_REG_SIZE_U32 | \
KVM_REG_ARM_CORE | KVM_REG_ARM_CORE_REG(KERNELNAME), \
offsetof(CPUARMState, QEMUFIELD) \
}
#define VFPSYSREG(R) \
{ \
KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_VFP | \
KVM_REG_ARM_VFP_##R, \
offsetof(CPUARMState, vfp.xregs[ARM_VFP_##R]) \
}
/* Like COREREG, but handle fields which are in a uint64_t in CPUARMState. */
#define COREREG64(KERNELNAME, QEMUFIELD) \
{ \
KVM_REG_ARM | KVM_REG_SIZE_U32 | \
KVM_REG_ARM_CORE | KVM_REG_ARM_CORE_REG(KERNELNAME), \
offsetoflow32(CPUARMState, QEMUFIELD) \
}
static const Reg regs[] = {
/* R0_usr .. R14_usr */
COREREG(usr_regs.uregs[0], regs[0]),
COREREG(usr_regs.uregs[1], regs[1]),
COREREG(usr_regs.uregs[2], regs[2]),
COREREG(usr_regs.uregs[3], regs[3]),
COREREG(usr_regs.uregs[4], regs[4]),
COREREG(usr_regs.uregs[5], regs[5]),
COREREG(usr_regs.uregs[6], regs[6]),
COREREG(usr_regs.uregs[7], regs[7]),
COREREG(usr_regs.uregs[8], usr_regs[0]),
COREREG(usr_regs.uregs[9], usr_regs[1]),
COREREG(usr_regs.uregs[10], usr_regs[2]),
COREREG(usr_regs.uregs[11], usr_regs[3]),
COREREG(usr_regs.uregs[12], usr_regs[4]),
COREREG(usr_regs.uregs[13], banked_r13[BANK_USRSYS]),
COREREG(usr_regs.uregs[14], banked_r14[BANK_USRSYS]),
/* R13, R14, SPSR for SVC, ABT, UND, IRQ banks */
COREREG(svc_regs[0], banked_r13[BANK_SVC]),
COREREG(svc_regs[1], banked_r14[BANK_SVC]),
COREREG64(svc_regs[2], banked_spsr[BANK_SVC]),
COREREG(abt_regs[0], banked_r13[BANK_ABT]),
COREREG(abt_regs[1], banked_r14[BANK_ABT]),
COREREG64(abt_regs[2], banked_spsr[BANK_ABT]),
COREREG(und_regs[0], banked_r13[BANK_UND]),
COREREG(und_regs[1], banked_r14[BANK_UND]),
COREREG64(und_regs[2], banked_spsr[BANK_UND]),
COREREG(irq_regs[0], banked_r13[BANK_IRQ]),
COREREG(irq_regs[1], banked_r14[BANK_IRQ]),
COREREG64(irq_regs[2], banked_spsr[BANK_IRQ]),
/* R8_fiq .. R14_fiq and SPSR_fiq */
COREREG(fiq_regs[0], fiq_regs[0]),
COREREG(fiq_regs[1], fiq_regs[1]),
COREREG(fiq_regs[2], fiq_regs[2]),
COREREG(fiq_regs[3], fiq_regs[3]),
COREREG(fiq_regs[4], fiq_regs[4]),
COREREG(fiq_regs[5], banked_r13[BANK_FIQ]),
COREREG(fiq_regs[6], banked_r14[BANK_FIQ]),
COREREG64(fiq_regs[7], banked_spsr[BANK_FIQ]),
/* R15 */
COREREG(usr_regs.uregs[15], regs[15]),
/* VFP system registers */
VFPSYSREG(FPSID),
VFPSYSREG(MVFR1),
VFPSYSREG(MVFR0),
VFPSYSREG(FPEXC),
VFPSYSREG(FPINST),
VFPSYSREG(FPINST2),
};
int kvm_arch_put_registers(CPUState *cs, int level)
{
ARMCPU *cpu = ARM_CPU(cs);
CPUARMState *env = &cpu->env;
struct kvm_one_reg r;
int mode, bn;
int ret, i;
uint32_t cpsr, fpscr;
/* Make sure the banked regs are properly set */
mode = env->uncached_cpsr & CPSR_M;
bn = bank_number(mode);
if (mode == ARM_CPU_MODE_FIQ) {
memcpy(env->fiq_regs, env->regs + 8, 5 * sizeof(uint32_t));
} else {
memcpy(env->usr_regs, env->regs + 8, 5 * sizeof(uint32_t));
}
env->banked_r13[bn] = env->regs[13];
env->banked_spsr[bn] = env->spsr;
env->banked_r14[r14_bank_number(mode)] = env->regs[14];
/* Now we can safely copy stuff down to the kernel */
for (i = 0; i < ARRAY_SIZE(regs); i++) {
r.id = regs[i].id;
r.addr = (uintptr_t)(env) + regs[i].offset;
ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &r);
if (ret) {
return ret;
}
}
/* Special cases which aren't a single CPUARMState field */
cpsr = cpsr_read(env);
r.id = KVM_REG_ARM | KVM_REG_SIZE_U32 |
KVM_REG_ARM_CORE | KVM_REG_ARM_CORE_REG(usr_regs.ARM_cpsr);
r.addr = (uintptr_t)(&cpsr);
ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &r);
if (ret) {
return ret;
}
/* VFP registers */
r.id = KVM_REG_ARM | KVM_REG_SIZE_U64 | KVM_REG_ARM_VFP;
for (i = 0; i < 32; i++) {
r.addr = (uintptr_t)aa32_vfp_dreg(env, i);
ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &r);
if (ret) {
return ret;
}
r.id++;
}
r.id = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_VFP |
KVM_REG_ARM_VFP_FPSCR;
fpscr = vfp_get_fpscr(env);
r.addr = (uintptr_t)&fpscr;
ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &r);
if (ret) {
return ret;
}
ret = kvm_put_vcpu_events(cpu);
if (ret) {
return ret;
}
/* Note that we do not call write_cpustate_to_list()
* here, so we are only writing the tuple list back to
* KVM. This is safe because nothing can change the
* CPUARMState cp15 fields (in particular gdb accesses cannot)
* and so there are no changes to sync. In fact syncing would
* be wrong at this point: for a constant register where TCG and
* KVM disagree about its value, the preceding write_list_to_cpustate()
* would not have had any effect on the CPUARMState value (since the
* register is read-only), and a write_cpustate_to_list() here would
* then try to write the TCG value back into KVM -- this would either
* fail or incorrectly change the value the guest sees.
*
* If we ever want to allow the user to modify cp15 registers via
* the gdb stub, we would need to be more clever here (for instance
* tracking the set of registers kvm_arch_get_registers() successfully
* managed to update the CPUARMState with, and only allowing those
* to be written back up into the kernel).
*/
if (!write_list_to_kvmstate(cpu, level)) {
return EINVAL;
}
kvm_arm_sync_mpstate_to_kvm(cpu);
return ret;
}
int kvm_arch_get_registers(CPUState *cs)
{
ARMCPU *cpu = ARM_CPU(cs);
CPUARMState *env = &cpu->env;
struct kvm_one_reg r;
int mode, bn;
int ret, i;
uint32_t cpsr, fpscr;
for (i = 0; i < ARRAY_SIZE(regs); i++) {
r.id = regs[i].id;
r.addr = (uintptr_t)(env) + regs[i].offset;
ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r);
if (ret) {
return ret;
}
}
/* Special cases which aren't a single CPUARMState field */
r.id = KVM_REG_ARM | KVM_REG_SIZE_U32 |
KVM_REG_ARM_CORE | KVM_REG_ARM_CORE_REG(usr_regs.ARM_cpsr);
r.addr = (uintptr_t)(&cpsr);
ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r);
if (ret) {
return ret;
}
cpsr_write(env, cpsr, 0xffffffff, CPSRWriteRaw);
/* Make sure the current mode regs are properly set */
mode = env->uncached_cpsr & CPSR_M;
bn = bank_number(mode);
if (mode == ARM_CPU_MODE_FIQ) {
memcpy(env->regs + 8, env->fiq_regs, 5 * sizeof(uint32_t));
} else {
memcpy(env->regs + 8, env->usr_regs, 5 * sizeof(uint32_t));
}
env->regs[13] = env->banked_r13[bn];
env->spsr = env->banked_spsr[bn];
env->regs[14] = env->banked_r14[r14_bank_number(mode)];
/* VFP registers */
r.id = KVM_REG_ARM | KVM_REG_SIZE_U64 | KVM_REG_ARM_VFP;
for (i = 0; i < 32; i++) {
r.addr = (uintptr_t)aa32_vfp_dreg(env, i);
ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r);
if (ret) {
return ret;
}
r.id++;
}
r.id = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_VFP |
KVM_REG_ARM_VFP_FPSCR;
r.addr = (uintptr_t)&fpscr;
ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r);
if (ret) {
return ret;
}
vfp_set_fpscr(env, fpscr);
ret = kvm_get_vcpu_events(cpu);
if (ret) {
return ret;
}
if (!write_kvmstate_to_list(cpu)) {
return EINVAL;
}
/* Note that it's OK to have registers which aren't in CPUState,
* so we can ignore a failure return here.
*/
write_list_to_cpustate(cpu);
kvm_arm_sync_mpstate_to_qemu(cpu);
return 0;
}
int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp)
{
qemu_log_mask(LOG_UNIMP, "%s: guest debug not yet implemented\n", __func__);
return -EINVAL;
}
int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp)
{
qemu_log_mask(LOG_UNIMP, "%s: guest debug not yet implemented\n", __func__);
return -EINVAL;
}
bool kvm_arm_handle_debug(CPUState *cs, struct kvm_debug_exit_arch *debug_exit)
{
qemu_log_mask(LOG_UNIMP, "%s: guest debug not yet implemented\n", __func__);
return false;
}
int kvm_arch_insert_hw_breakpoint(target_ulong addr,
target_ulong len, int type)
{
qemu_log_mask(LOG_UNIMP, "%s: not implemented\n", __func__);
return -EINVAL;
}
int kvm_arch_remove_hw_breakpoint(target_ulong addr,
target_ulong len, int type)
{
qemu_log_mask(LOG_UNIMP, "%s: not implemented\n", __func__);
return -EINVAL;
}
void kvm_arch_remove_all_hw_breakpoints(void)
{
qemu_log_mask(LOG_UNIMP, "%s: not implemented\n", __func__);
}
void kvm_arm_copy_hw_debug_data(struct kvm_guest_debug_arch *ptr)
{
qemu_log_mask(LOG_UNIMP, "%s: not implemented\n", __func__);
}
bool kvm_arm_hw_debug_active(CPUState *cs)
{
return false;
}
void kvm_arm_pmu_set_irq(CPUState *cs, int irq)
{
qemu_log_mask(LOG_UNIMP, "%s: not implemented\n", __func__);
}
void kvm_arm_pmu_init(CPUState *cs)
{
qemu_log_mask(LOG_UNIMP, "%s: not implemented\n", __func__);
}