qemu/target-i386/kvm.c
aliguori 40a2d7050a Fix crash in kvm.c (Stefan Weil)
Fix crash with kvm enabled.

Signed-off-by: Stefan Weil <weil@mail.berlios.de> 
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5984 c046a42c-6fe2-441c-8c8c-71466251a162
2008-12-11 21:03:10 +00:00

639 lines
17 KiB
C

/*
* QEMU KVM support
*
* Copyright (C) 2006-2008 Qumranet Technologies
* Copyright IBM, Corp. 2008
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* 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 <sys/types.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <linux/kvm.h>
#include "qemu-common.h"
#include "sysemu.h"
#include "kvm.h"
#include "cpu.h"
//#define DEBUG_KVM
#ifdef DEBUG_KVM
#define dprintf(fmt, ...) \
do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
#else
#define dprintf(fmt, ...) \
do { } while (0)
#endif
int kvm_arch_init_vcpu(CPUState *env)
{
struct {
struct kvm_cpuid cpuid;
struct kvm_cpuid_entry entries[100];
} __attribute__((packed)) cpuid_data;
uint32_t limit, i, cpuid_i;
uint32_t eax, ebx, ecx, edx;
cpuid_i = 0;
cpu_x86_cpuid(env, 0, &eax, &ebx, &ecx, &edx);
limit = eax;
for (i = 0; i <= limit; i++) {
struct kvm_cpuid_entry *c = &cpuid_data.entries[cpuid_i++];
cpu_x86_cpuid(env, i, &eax, &ebx, &ecx, &edx);
c->function = i;
c->eax = eax;
c->ebx = ebx;
c->ecx = ecx;
c->edx = edx;
}
cpu_x86_cpuid(env, 0x80000000, &eax, &ebx, &ecx, &edx);
limit = eax;
for (i = 0x80000000; i <= limit; i++) {
struct kvm_cpuid_entry *c = &cpuid_data.entries[cpuid_i++];
cpu_x86_cpuid(env, i, &eax, &ebx, &ecx, &edx);
c->function = i;
c->eax = eax;
c->ebx = ebx;
c->ecx = ecx;
c->edx = edx;
}
cpuid_data.cpuid.nent = cpuid_i;
return kvm_vcpu_ioctl(env, KVM_SET_CPUID, &cpuid_data);
}
static int kvm_has_msr_star(CPUState *env)
{
static int has_msr_star;
int ret;
/* first time */
if (has_msr_star == 0) {
struct kvm_msr_list msr_list, *kvm_msr_list;
has_msr_star = -1;
/* Obtain MSR list from KVM. These are the MSRs that we must
* save/restore */
ret = kvm_ioctl(env->kvm_state, KVM_GET_MSR_INDEX_LIST, &msr_list);
if (ret < 0)
return 0;
msr_list.nmsrs = 0;
kvm_msr_list = qemu_mallocz(sizeof(msr_list) +
msr_list.nmsrs * sizeof(msr_list.indices[0]));
if (kvm_msr_list == NULL)
return 0;
ret = kvm_ioctl(env->kvm_state, KVM_GET_MSR_INDEX_LIST, kvm_msr_list);
if (ret >= 0) {
int i;
for (i = 0; i < kvm_msr_list->nmsrs; i++) {
if (kvm_msr_list->indices[i] == MSR_STAR) {
has_msr_star = 1;
break;
}
}
}
free(kvm_msr_list);
}
if (has_msr_star == 1)
return 1;
return 0;
}
int kvm_arch_init(KVMState *s, int smp_cpus)
{
int ret;
/* create vm86 tss. KVM uses vm86 mode to emulate 16-bit code
* directly. In order to use vm86 mode, a TSS is needed. Since this
* must be part of guest physical memory, we need to allocate it. Older
* versions of KVM just assumed that it would be at the end of physical
* memory but that doesn't work with more than 4GB of memory. We simply
* refuse to work with those older versions of KVM. */
ret = kvm_ioctl(s, KVM_CHECK_EXTENSION, KVM_CAP_SET_TSS_ADDR);
if (ret <= 0) {
fprintf(stderr, "kvm does not support KVM_CAP_SET_TSS_ADDR\n");
return ret;
}
/* this address is 3 pages before the bios, and the bios should present
* as unavaible memory. FIXME, need to ensure the e820 map deals with
* this?
*/
return kvm_vm_ioctl(s, KVM_SET_TSS_ADDR, 0xfffbd000);
}
static void set_v8086_seg(struct kvm_segment *lhs, const SegmentCache *rhs)
{
lhs->selector = rhs->selector;
lhs->base = rhs->base;
lhs->limit = rhs->limit;
lhs->type = 3;
lhs->present = 1;
lhs->dpl = 3;
lhs->db = 0;
lhs->s = 1;
lhs->l = 0;
lhs->g = 0;
lhs->avl = 0;
lhs->unusable = 0;
}
static void set_seg(struct kvm_segment *lhs, const SegmentCache *rhs)
{
unsigned flags = rhs->flags;
lhs->selector = rhs->selector;
lhs->base = rhs->base;
lhs->limit = rhs->limit;
lhs->type = (flags >> DESC_TYPE_SHIFT) & 15;
lhs->present = (flags & DESC_P_MASK) != 0;
lhs->dpl = rhs->selector & 3;
lhs->db = (flags >> DESC_B_SHIFT) & 1;
lhs->s = (flags & DESC_S_MASK) != 0;
lhs->l = (flags >> DESC_L_SHIFT) & 1;
lhs->g = (flags & DESC_G_MASK) != 0;
lhs->avl = (flags & DESC_AVL_MASK) != 0;
lhs->unusable = 0;
}
static void get_seg(SegmentCache *lhs, const struct kvm_segment *rhs)
{
lhs->selector = rhs->selector;
lhs->base = rhs->base;
lhs->limit = rhs->limit;
lhs->flags =
(rhs->type << DESC_TYPE_SHIFT)
| (rhs->present * DESC_P_MASK)
| (rhs->dpl << DESC_DPL_SHIFT)
| (rhs->db << DESC_B_SHIFT)
| (rhs->s * DESC_S_MASK)
| (rhs->l << DESC_L_SHIFT)
| (rhs->g * DESC_G_MASK)
| (rhs->avl * DESC_AVL_MASK);
}
static void kvm_getput_reg(__u64 *kvm_reg, target_ulong *qemu_reg, int set)
{
if (set)
*kvm_reg = *qemu_reg;
else
*qemu_reg = *kvm_reg;
}
static int kvm_getput_regs(CPUState *env, int set)
{
struct kvm_regs regs;
int ret = 0;
if (!set) {
ret = kvm_vcpu_ioctl(env, KVM_GET_REGS, &regs);
if (ret < 0)
return ret;
}
kvm_getput_reg(&regs.rax, &env->regs[R_EAX], set);
kvm_getput_reg(&regs.rbx, &env->regs[R_EBX], set);
kvm_getput_reg(&regs.rcx, &env->regs[R_ECX], set);
kvm_getput_reg(&regs.rdx, &env->regs[R_EDX], set);
kvm_getput_reg(&regs.rsi, &env->regs[R_ESI], set);
kvm_getput_reg(&regs.rdi, &env->regs[R_EDI], set);
kvm_getput_reg(&regs.rsp, &env->regs[R_ESP], set);
kvm_getput_reg(&regs.rbp, &env->regs[R_EBP], set);
#ifdef TARGET_X86_64
kvm_getput_reg(&regs.r8, &env->regs[8], set);
kvm_getput_reg(&regs.r9, &env->regs[9], set);
kvm_getput_reg(&regs.r10, &env->regs[10], set);
kvm_getput_reg(&regs.r11, &env->regs[11], set);
kvm_getput_reg(&regs.r12, &env->regs[12], set);
kvm_getput_reg(&regs.r13, &env->regs[13], set);
kvm_getput_reg(&regs.r14, &env->regs[14], set);
kvm_getput_reg(&regs.r15, &env->regs[15], set);
#endif
kvm_getput_reg(&regs.rflags, &env->eflags, set);
kvm_getput_reg(&regs.rip, &env->eip, set);
if (set)
ret = kvm_vcpu_ioctl(env, KVM_SET_REGS, &regs);
return ret;
}
static int kvm_put_fpu(CPUState *env)
{
struct kvm_fpu fpu;
int i;
memset(&fpu, 0, sizeof fpu);
fpu.fsw = env->fpus & ~(7 << 11);
fpu.fsw |= (env->fpstt & 7) << 11;
fpu.fcw = env->fpuc;
for (i = 0; i < 8; ++i)
fpu.ftwx |= (!env->fptags[i]) << i;
memcpy(fpu.fpr, env->fpregs, sizeof env->fpregs);
memcpy(fpu.xmm, env->xmm_regs, sizeof env->xmm_regs);
fpu.mxcsr = env->mxcsr;
return kvm_vcpu_ioctl(env, KVM_SET_FPU, &fpu);
}
static int kvm_put_sregs(CPUState *env)
{
struct kvm_sregs sregs;
memcpy(sregs.interrupt_bitmap,
env->interrupt_bitmap,
sizeof(sregs.interrupt_bitmap));
if ((env->eflags & VM_MASK)) {
set_v8086_seg(&sregs.cs, &env->segs[R_CS]);
set_v8086_seg(&sregs.ds, &env->segs[R_DS]);
set_v8086_seg(&sregs.es, &env->segs[R_ES]);
set_v8086_seg(&sregs.fs, &env->segs[R_FS]);
set_v8086_seg(&sregs.gs, &env->segs[R_GS]);
set_v8086_seg(&sregs.ss, &env->segs[R_SS]);
} else {
set_seg(&sregs.cs, &env->segs[R_CS]);
set_seg(&sregs.ds, &env->segs[R_DS]);
set_seg(&sregs.es, &env->segs[R_ES]);
set_seg(&sregs.fs, &env->segs[R_FS]);
set_seg(&sregs.gs, &env->segs[R_GS]);
set_seg(&sregs.ss, &env->segs[R_SS]);
if (env->cr[0] & CR0_PE_MASK) {
/* force ss cpl to cs cpl */
sregs.ss.selector = (sregs.ss.selector & ~3) |
(sregs.cs.selector & 3);
sregs.ss.dpl = sregs.ss.selector & 3;
}
}
set_seg(&sregs.tr, &env->tr);
set_seg(&sregs.ldt, &env->ldt);
sregs.idt.limit = env->idt.limit;
sregs.idt.base = env->idt.base;
sregs.gdt.limit = env->gdt.limit;
sregs.gdt.base = env->gdt.base;
sregs.cr0 = env->cr[0];
sregs.cr2 = env->cr[2];
sregs.cr3 = env->cr[3];
sregs.cr4 = env->cr[4];
sregs.cr8 = cpu_get_apic_tpr(env);
sregs.apic_base = cpu_get_apic_base(env);
sregs.efer = env->efer;
return kvm_vcpu_ioctl(env, KVM_SET_SREGS, &sregs);
}
static void kvm_msr_entry_set(struct kvm_msr_entry *entry,
uint32_t index, uint64_t value)
{
entry->index = index;
entry->data = value;
}
static int kvm_put_msrs(CPUState *env)
{
struct {
struct kvm_msrs info;
struct kvm_msr_entry entries[100];
} msr_data;
struct kvm_msr_entry *msrs = msr_data.entries;
int n = 0;
kvm_msr_entry_set(&msrs[n++], MSR_IA32_SYSENTER_CS, env->sysenter_cs);
kvm_msr_entry_set(&msrs[n++], MSR_IA32_SYSENTER_ESP, env->sysenter_esp);
kvm_msr_entry_set(&msrs[n++], MSR_IA32_SYSENTER_EIP, env->sysenter_eip);
if (kvm_has_msr_star(env))
kvm_msr_entry_set(&msrs[n++], MSR_STAR, env->star);
kvm_msr_entry_set(&msrs[n++], MSR_IA32_TSC, env->tsc);
#ifdef TARGET_X86_64
/* FIXME if lm capable */
kvm_msr_entry_set(&msrs[n++], MSR_CSTAR, env->cstar);
kvm_msr_entry_set(&msrs[n++], MSR_KERNELGSBASE, env->kernelgsbase);
kvm_msr_entry_set(&msrs[n++], MSR_FMASK, env->fmask);
kvm_msr_entry_set(&msrs[n++], MSR_LSTAR, env->lstar);
#endif
msr_data.info.nmsrs = n;
return kvm_vcpu_ioctl(env, KVM_SET_MSRS, &msr_data);
}
static int kvm_get_fpu(CPUState *env)
{
struct kvm_fpu fpu;
int i, ret;
ret = kvm_vcpu_ioctl(env, KVM_GET_FPU, &fpu);
if (ret < 0)
return ret;
env->fpstt = (fpu.fsw >> 11) & 7;
env->fpus = fpu.fsw;
env->fpuc = fpu.fcw;
for (i = 0; i < 8; ++i)
env->fptags[i] = !((fpu.ftwx >> i) & 1);
memcpy(env->fpregs, fpu.fpr, sizeof env->fpregs);
memcpy(env->xmm_regs, fpu.xmm, sizeof env->xmm_regs);
env->mxcsr = fpu.mxcsr;
return 0;
}
static int kvm_get_sregs(CPUState *env)
{
struct kvm_sregs sregs;
uint32_t hflags;
int ret;
ret = kvm_vcpu_ioctl(env, KVM_GET_SREGS, &sregs);
if (ret < 0)
return ret;
memcpy(env->interrupt_bitmap,
sregs.interrupt_bitmap,
sizeof(sregs.interrupt_bitmap));
get_seg(&env->segs[R_CS], &sregs.cs);
get_seg(&env->segs[R_DS], &sregs.ds);
get_seg(&env->segs[R_ES], &sregs.es);
get_seg(&env->segs[R_FS], &sregs.fs);
get_seg(&env->segs[R_GS], &sregs.gs);
get_seg(&env->segs[R_SS], &sregs.ss);
get_seg(&env->tr, &sregs.tr);
get_seg(&env->ldt, &sregs.ldt);
env->idt.limit = sregs.idt.limit;
env->idt.base = sregs.idt.base;
env->gdt.limit = sregs.gdt.limit;
env->gdt.base = sregs.gdt.base;
env->cr[0] = sregs.cr0;
env->cr[2] = sregs.cr2;
env->cr[3] = sregs.cr3;
env->cr[4] = sregs.cr4;
cpu_set_apic_base(env, sregs.apic_base);
env->efer = sregs.efer;
//cpu_set_apic_tpr(env, sregs.cr8);
#define HFLAG_COPY_MASK ~( \
HF_CPL_MASK | HF_PE_MASK | HF_MP_MASK | HF_EM_MASK | \
HF_TS_MASK | HF_TF_MASK | HF_VM_MASK | HF_IOPL_MASK | \
HF_OSFXSR_MASK | HF_LMA_MASK | HF_CS32_MASK | \
HF_SS32_MASK | HF_CS64_MASK | HF_ADDSEG_MASK)
hflags = (env->segs[R_CS].flags >> DESC_DPL_SHIFT) & HF_CPL_MASK;
hflags |= (env->cr[0] & CR0_PE_MASK) << (HF_PE_SHIFT - CR0_PE_SHIFT);
hflags |= (env->cr[0] << (HF_MP_SHIFT - CR0_MP_SHIFT)) &
(HF_MP_MASK | HF_EM_MASK | HF_TS_MASK);
hflags |= (env->eflags & (HF_TF_MASK | HF_VM_MASK | HF_IOPL_MASK));
hflags |= (env->cr[4] & CR4_OSFXSR_MASK) <<
(HF_OSFXSR_SHIFT - CR4_OSFXSR_SHIFT);
if (env->efer & MSR_EFER_LMA) {
hflags |= HF_LMA_MASK;
}
if ((hflags & HF_LMA_MASK) && (env->segs[R_CS].flags & DESC_L_MASK)) {
hflags |= HF_CS32_MASK | HF_SS32_MASK | HF_CS64_MASK;
} else {
hflags |= (env->segs[R_CS].flags & DESC_B_MASK) >>
(DESC_B_SHIFT - HF_CS32_SHIFT);
hflags |= (env->segs[R_SS].flags & DESC_B_MASK) >>
(DESC_B_SHIFT - HF_SS32_SHIFT);
if (!(env->cr[0] & CR0_PE_MASK) ||
(env->eflags & VM_MASK) ||
!(hflags & HF_CS32_MASK)) {
hflags |= HF_ADDSEG_MASK;
} else {
hflags |= ((env->segs[R_DS].base |
env->segs[R_ES].base |
env->segs[R_SS].base) != 0) <<
HF_ADDSEG_SHIFT;
}
}
env->hflags = (env->hflags & HFLAG_COPY_MASK) | hflags;
env->cc_src = env->eflags & (CC_O | CC_S | CC_Z | CC_A | CC_P | CC_C);
env->df = 1 - (2 * ((env->eflags >> 10) & 1));
env->cc_op = CC_OP_EFLAGS;
env->eflags &= ~(DF_MASK | CC_O | CC_S | CC_Z | CC_A | CC_P | CC_C);
return 0;
}
static int kvm_get_msrs(CPUState *env)
{
struct {
struct kvm_msrs info;
struct kvm_msr_entry entries[100];
} msr_data;
struct kvm_msr_entry *msrs = msr_data.entries;
int ret, i, n;
n = 0;
msrs[n++].index = MSR_IA32_SYSENTER_CS;
msrs[n++].index = MSR_IA32_SYSENTER_ESP;
msrs[n++].index = MSR_IA32_SYSENTER_EIP;
if (kvm_has_msr_star(env))
msrs[n++].index = MSR_STAR;
msrs[n++].index = MSR_IA32_TSC;
#ifdef TARGET_X86_64
/* FIXME lm_capable_kernel */
msrs[n++].index = MSR_CSTAR;
msrs[n++].index = MSR_KERNELGSBASE;
msrs[n++].index = MSR_FMASK;
msrs[n++].index = MSR_LSTAR;
#endif
msr_data.info.nmsrs = n;
ret = kvm_vcpu_ioctl(env, KVM_GET_MSRS, &msr_data);
if (ret < 0)
return ret;
for (i = 0; i < ret; i++) {
switch (msrs[i].index) {
case MSR_IA32_SYSENTER_CS:
env->sysenter_cs = msrs[i].data;
break;
case MSR_IA32_SYSENTER_ESP:
env->sysenter_esp = msrs[i].data;
break;
case MSR_IA32_SYSENTER_EIP:
env->sysenter_eip = msrs[i].data;
break;
case MSR_STAR:
env->star = msrs[i].data;
break;
#ifdef TARGET_X86_64
case MSR_CSTAR:
env->cstar = msrs[i].data;
break;
case MSR_KERNELGSBASE:
env->kernelgsbase = msrs[i].data;
break;
case MSR_FMASK:
env->fmask = msrs[i].data;
break;
case MSR_LSTAR:
env->lstar = msrs[i].data;
break;
#endif
case MSR_IA32_TSC:
env->tsc = msrs[i].data;
break;
}
}
return 0;
}
int kvm_arch_put_registers(CPUState *env)
{
int ret;
ret = kvm_getput_regs(env, 1);
if (ret < 0)
return ret;
ret = kvm_put_fpu(env);
if (ret < 0)
return ret;
ret = kvm_put_sregs(env);
if (ret < 0)
return ret;
ret = kvm_put_msrs(env);
if (ret < 0)
return ret;
return 0;
}
int kvm_arch_get_registers(CPUState *env)
{
int ret;
ret = kvm_getput_regs(env, 0);
if (ret < 0)
return ret;
ret = kvm_get_fpu(env);
if (ret < 0)
return ret;
ret = kvm_get_sregs(env);
if (ret < 0)
return ret;
ret = kvm_get_msrs(env);
if (ret < 0)
return ret;
return 0;
}
int kvm_arch_pre_run(CPUState *env, struct kvm_run *run)
{
/* Try to inject an interrupt if the guest can accept it */
if (run->ready_for_interrupt_injection &&
(env->interrupt_request & CPU_INTERRUPT_HARD) &&
(env->eflags & IF_MASK)) {
int irq;
env->interrupt_request &= ~CPU_INTERRUPT_HARD;
irq = cpu_get_pic_interrupt(env);
if (irq >= 0) {
struct kvm_interrupt intr;
intr.irq = irq;
/* FIXME: errors */
dprintf("injected interrupt %d\n", irq);
kvm_vcpu_ioctl(env, KVM_INTERRUPT, &intr);
}
}
/* If we have an interrupt but the guest is not ready to receive an
* interrupt, request an interrupt window exit. This will
* cause a return to userspace as soon as the guest is ready to
* receive interrupts. */
if ((env->interrupt_request & CPU_INTERRUPT_HARD))
run->request_interrupt_window = 1;
else
run->request_interrupt_window = 0;
dprintf("setting tpr\n");
run->cr8 = cpu_get_apic_tpr(env);
return 0;
}
int kvm_arch_post_run(CPUState *env, struct kvm_run *run)
{
if (run->if_flag)
env->eflags |= IF_MASK;
else
env->eflags &= ~IF_MASK;
cpu_set_apic_tpr(env, run->cr8);
cpu_set_apic_base(env, run->apic_base);
return 0;
}
static int kvm_handle_halt(CPUState *env)
{
if (!((env->interrupt_request & CPU_INTERRUPT_HARD) &&
(env->eflags & IF_MASK)) &&
!(env->interrupt_request & CPU_INTERRUPT_NMI)) {
env->halted = 1;
env->exception_index = EXCP_HLT;
return 0;
}
return 1;
}
int kvm_arch_handle_exit(CPUState *env, struct kvm_run *run)
{
int ret = 0;
switch (run->exit_reason) {
case KVM_EXIT_HLT:
dprintf("handle_hlt\n");
ret = kvm_handle_halt(env);
break;
}
return ret;
}