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android_kernel_xiaomi_sm8350/arch/powerpc/kvm/booke_guest.c
Christian Ehrhardt de368dceb3 KVM: ppc: deliver INTERRUPT_FP_UNAVAIL to the guest 
This patch adds the delivery of INTERRUPT_FP_UNAVAIL exceptions to the guest.
It's needed if a guest uses ppc binaries using the Floating point instructions.

Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Acked-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-05-04 14:44:45 +03:00

622 lines
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/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, version 2, as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* Copyright IBM Corp. 2007
*
* Authors: Hollis Blanchard <hollisb@us.ibm.com>
* Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
*/
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/kvm_host.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <asm/cputable.h>
#include <asm/uaccess.h>
#include <asm/kvm_ppc.h>
#include "44x_tlb.h"
#define VM_STAT(x) offsetof(struct kvm, stat.x), KVM_STAT_VM
#define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU
struct kvm_stats_debugfs_item debugfs_entries[] = {
{ "exits", VCPU_STAT(sum_exits) },
{ "mmio", VCPU_STAT(mmio_exits) },
{ "dcr", VCPU_STAT(dcr_exits) },
{ "sig", VCPU_STAT(signal_exits) },
{ "light", VCPU_STAT(light_exits) },
{ "itlb_r", VCPU_STAT(itlb_real_miss_exits) },
{ "itlb_v", VCPU_STAT(itlb_virt_miss_exits) },
{ "dtlb_r", VCPU_STAT(dtlb_real_miss_exits) },
{ "dtlb_v", VCPU_STAT(dtlb_virt_miss_exits) },
{ "sysc", VCPU_STAT(syscall_exits) },
{ "isi", VCPU_STAT(isi_exits) },
{ "dsi", VCPU_STAT(dsi_exits) },
{ "inst_emu", VCPU_STAT(emulated_inst_exits) },
{ "dec", VCPU_STAT(dec_exits) },
{ "ext_intr", VCPU_STAT(ext_intr_exits) },
{ "halt_wakeup", VCPU_STAT(halt_wakeup) },
{ NULL }
};
static const u32 interrupt_msr_mask[16] = {
[BOOKE_INTERRUPT_CRITICAL] = MSR_ME,
[BOOKE_INTERRUPT_MACHINE_CHECK] = 0,
[BOOKE_INTERRUPT_DATA_STORAGE] = MSR_CE|MSR_ME|MSR_DE,
[BOOKE_INTERRUPT_INST_STORAGE] = MSR_CE|MSR_ME|MSR_DE,
[BOOKE_INTERRUPT_EXTERNAL] = MSR_CE|MSR_ME|MSR_DE,
[BOOKE_INTERRUPT_ALIGNMENT] = MSR_CE|MSR_ME|MSR_DE,
[BOOKE_INTERRUPT_PROGRAM] = MSR_CE|MSR_ME|MSR_DE,
[BOOKE_INTERRUPT_FP_UNAVAIL] = MSR_CE|MSR_ME|MSR_DE,
[BOOKE_INTERRUPT_SYSCALL] = MSR_CE|MSR_ME|MSR_DE,
[BOOKE_INTERRUPT_AP_UNAVAIL] = MSR_CE|MSR_ME|MSR_DE,
[BOOKE_INTERRUPT_DECREMENTER] = MSR_CE|MSR_ME|MSR_DE,
[BOOKE_INTERRUPT_FIT] = MSR_CE|MSR_ME|MSR_DE,
[BOOKE_INTERRUPT_WATCHDOG] = MSR_ME,
[BOOKE_INTERRUPT_DTLB_MISS] = MSR_CE|MSR_ME|MSR_DE,
[BOOKE_INTERRUPT_ITLB_MISS] = MSR_CE|MSR_ME|MSR_DE,
[BOOKE_INTERRUPT_DEBUG] = MSR_ME,
};
const unsigned char exception_priority[] = {
[BOOKE_INTERRUPT_DATA_STORAGE] = 0,
[BOOKE_INTERRUPT_INST_STORAGE] = 1,
[BOOKE_INTERRUPT_ALIGNMENT] = 2,
[BOOKE_INTERRUPT_PROGRAM] = 3,
[BOOKE_INTERRUPT_FP_UNAVAIL] = 4,
[BOOKE_INTERRUPT_SYSCALL] = 5,
[BOOKE_INTERRUPT_AP_UNAVAIL] = 6,
[BOOKE_INTERRUPT_DTLB_MISS] = 7,
[BOOKE_INTERRUPT_ITLB_MISS] = 8,
[BOOKE_INTERRUPT_MACHINE_CHECK] = 9,
[BOOKE_INTERRUPT_DEBUG] = 10,
[BOOKE_INTERRUPT_CRITICAL] = 11,
[BOOKE_INTERRUPT_WATCHDOG] = 12,
[BOOKE_INTERRUPT_EXTERNAL] = 13,
[BOOKE_INTERRUPT_FIT] = 14,
[BOOKE_INTERRUPT_DECREMENTER] = 15,
};
const unsigned char priority_exception[] = {
BOOKE_INTERRUPT_DATA_STORAGE,
BOOKE_INTERRUPT_INST_STORAGE,
BOOKE_INTERRUPT_ALIGNMENT,
BOOKE_INTERRUPT_PROGRAM,
BOOKE_INTERRUPT_FP_UNAVAIL,
BOOKE_INTERRUPT_SYSCALL,
BOOKE_INTERRUPT_AP_UNAVAIL,
BOOKE_INTERRUPT_DTLB_MISS,
BOOKE_INTERRUPT_ITLB_MISS,
BOOKE_INTERRUPT_MACHINE_CHECK,
BOOKE_INTERRUPT_DEBUG,
BOOKE_INTERRUPT_CRITICAL,
BOOKE_INTERRUPT_WATCHDOG,
BOOKE_INTERRUPT_EXTERNAL,
BOOKE_INTERRUPT_FIT,
BOOKE_INTERRUPT_DECREMENTER,
};
void kvmppc_dump_tlbs(struct kvm_vcpu *vcpu)
{
struct tlbe *tlbe;
int i;
printk("vcpu %d TLB dump:\n", vcpu->vcpu_id);
printk("| %2s | %3s | %8s | %8s | %8s |\n",
"nr", "tid", "word0", "word1", "word2");
for (i = 0; i < PPC44x_TLB_SIZE; i++) {
tlbe = &vcpu->arch.guest_tlb[i];
if (tlbe->word0 & PPC44x_TLB_VALID)
printk(" G%2d | %02X | %08X | %08X | %08X |\n",
i, tlbe->tid, tlbe->word0, tlbe->word1,
tlbe->word2);
}
for (i = 0; i < PPC44x_TLB_SIZE; i++) {
tlbe = &vcpu->arch.shadow_tlb[i];
if (tlbe->word0 & PPC44x_TLB_VALID)
printk(" S%2d | %02X | %08X | %08X | %08X |\n",
i, tlbe->tid, tlbe->word0, tlbe->word1,
tlbe->word2);
}
}
/* TODO: use vcpu_printf() */
void kvmppc_dump_vcpu(struct kvm_vcpu *vcpu)
{
int i;
printk("pc: %08x msr: %08x\n", vcpu->arch.pc, vcpu->arch.msr);
printk("lr: %08x ctr: %08x\n", vcpu->arch.lr, vcpu->arch.ctr);
printk("srr0: %08x srr1: %08x\n", vcpu->arch.srr0, vcpu->arch.srr1);
printk("exceptions: %08lx\n", vcpu->arch.pending_exceptions);
for (i = 0; i < 32; i += 4) {
printk("gpr%02d: %08x %08x %08x %08x\n", i,
vcpu->arch.gpr[i],
vcpu->arch.gpr[i+1],
vcpu->arch.gpr[i+2],
vcpu->arch.gpr[i+3]);
}
}
/* Check if we are ready to deliver the interrupt */
static int kvmppc_can_deliver_interrupt(struct kvm_vcpu *vcpu, int interrupt)
{
int r;
switch (interrupt) {
case BOOKE_INTERRUPT_CRITICAL:
r = vcpu->arch.msr & MSR_CE;
break;
case BOOKE_INTERRUPT_MACHINE_CHECK:
r = vcpu->arch.msr & MSR_ME;
break;
case BOOKE_INTERRUPT_EXTERNAL:
r = vcpu->arch.msr & MSR_EE;
break;
case BOOKE_INTERRUPT_DECREMENTER:
r = vcpu->arch.msr & MSR_EE;
break;
case BOOKE_INTERRUPT_FIT:
r = vcpu->arch.msr & MSR_EE;
break;
case BOOKE_INTERRUPT_WATCHDOG:
r = vcpu->arch.msr & MSR_CE;
break;
case BOOKE_INTERRUPT_DEBUG:
r = vcpu->arch.msr & MSR_DE;
break;
default:
r = 1;
}
return r;
}
static void kvmppc_deliver_interrupt(struct kvm_vcpu *vcpu, int interrupt)
{
switch (interrupt) {
case BOOKE_INTERRUPT_DECREMENTER:
vcpu->arch.tsr |= TSR_DIS;
break;
}
vcpu->arch.srr0 = vcpu->arch.pc;
vcpu->arch.srr1 = vcpu->arch.msr;
vcpu->arch.pc = vcpu->arch.ivpr | vcpu->arch.ivor[interrupt];
kvmppc_set_msr(vcpu, vcpu->arch.msr & interrupt_msr_mask[interrupt]);
}
/* Check pending exceptions and deliver one, if possible. */
void kvmppc_check_and_deliver_interrupts(struct kvm_vcpu *vcpu)
{
unsigned long *pending = &vcpu->arch.pending_exceptions;
unsigned int exception;
unsigned int priority;
priority = find_first_bit(pending, BITS_PER_BYTE * sizeof(*pending));
while (priority <= BOOKE_MAX_INTERRUPT) {
exception = priority_exception[priority];
if (kvmppc_can_deliver_interrupt(vcpu, exception)) {
kvmppc_clear_exception(vcpu, exception);
kvmppc_deliver_interrupt(vcpu, exception);
break;
}
priority = find_next_bit(pending,
BITS_PER_BYTE * sizeof(*pending),
priority + 1);
}
}
static int kvmppc_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu)
{
enum emulation_result er;
int r;
er = kvmppc_emulate_instruction(run, vcpu);
switch (er) {
case EMULATE_DONE:
/* Future optimization: only reload non-volatiles if they were
* actually modified. */
r = RESUME_GUEST_NV;
break;
case EMULATE_DO_MMIO:
run->exit_reason = KVM_EXIT_MMIO;
/* We must reload nonvolatiles because "update" load/store
* instructions modify register state. */
/* Future optimization: only reload non-volatiles if they were
* actually modified. */
r = RESUME_HOST_NV;
break;
case EMULATE_FAIL:
/* XXX Deliver Program interrupt to guest. */
printk(KERN_EMERG "%s: emulation failed (%08x)\n", __func__,
vcpu->arch.last_inst);
r = RESUME_HOST;
break;
default:
BUG();
}
return r;
}
/**
* kvmppc_handle_exit
*
* Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
*/
int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
unsigned int exit_nr)
{
enum emulation_result er;
int r = RESUME_HOST;
local_irq_enable();
run->exit_reason = KVM_EXIT_UNKNOWN;
run->ready_for_interrupt_injection = 1;
switch (exit_nr) {
case BOOKE_INTERRUPT_MACHINE_CHECK:
printk("MACHINE CHECK: %lx\n", mfspr(SPRN_MCSR));
kvmppc_dump_vcpu(vcpu);
r = RESUME_HOST;
break;
case BOOKE_INTERRUPT_EXTERNAL:
case BOOKE_INTERRUPT_DECREMENTER:
/* Since we switched IVPR back to the host's value, the host
* handled this interrupt the moment we enabled interrupts.
* Now we just offer it a chance to reschedule the guest. */
/* XXX At this point the TLB still holds our shadow TLB, so if
* we do reschedule the host will fault over it. Perhaps we
* should politely restore the host's entries to minimize
* misses before ceding control. */
if (need_resched())
cond_resched();
if (exit_nr == BOOKE_INTERRUPT_DECREMENTER)
vcpu->stat.dec_exits++;
else
vcpu->stat.ext_intr_exits++;
r = RESUME_GUEST;
break;
case BOOKE_INTERRUPT_PROGRAM:
if (vcpu->arch.msr & MSR_PR) {
/* Program traps generated by user-level software must be handled
* by the guest kernel. */
vcpu->arch.esr = vcpu->arch.fault_esr;
kvmppc_queue_exception(vcpu, BOOKE_INTERRUPT_PROGRAM);
r = RESUME_GUEST;
break;
}
er = kvmppc_emulate_instruction(run, vcpu);
switch (er) {
case EMULATE_DONE:
/* Future optimization: only reload non-volatiles if
* they were actually modified by emulation. */
vcpu->stat.emulated_inst_exits++;
r = RESUME_GUEST_NV;
break;
case EMULATE_DO_DCR:
run->exit_reason = KVM_EXIT_DCR;
r = RESUME_HOST;
break;
case EMULATE_FAIL:
/* XXX Deliver Program interrupt to guest. */
printk(KERN_CRIT "%s: emulation at %x failed (%08x)\n",
__func__, vcpu->arch.pc, vcpu->arch.last_inst);
/* For debugging, encode the failing instruction and
* report it to userspace. */
run->hw.hardware_exit_reason = ~0ULL << 32;
run->hw.hardware_exit_reason |= vcpu->arch.last_inst;
r = RESUME_HOST;
break;
default:
BUG();
}
break;
case BOOKE_INTERRUPT_FP_UNAVAIL:
kvmppc_queue_exception(vcpu, exit_nr);
r = RESUME_GUEST;
break;
case BOOKE_INTERRUPT_DATA_STORAGE:
vcpu->arch.dear = vcpu->arch.fault_dear;
vcpu->arch.esr = vcpu->arch.fault_esr;
kvmppc_queue_exception(vcpu, exit_nr);
vcpu->stat.dsi_exits++;
r = RESUME_GUEST;
break;
case BOOKE_INTERRUPT_INST_STORAGE:
vcpu->arch.esr = vcpu->arch.fault_esr;
kvmppc_queue_exception(vcpu, exit_nr);
vcpu->stat.isi_exits++;
r = RESUME_GUEST;
break;
case BOOKE_INTERRUPT_SYSCALL:
kvmppc_queue_exception(vcpu, exit_nr);
vcpu->stat.syscall_exits++;
r = RESUME_GUEST;
break;
case BOOKE_INTERRUPT_DTLB_MISS: {
struct tlbe *gtlbe;
unsigned long eaddr = vcpu->arch.fault_dear;
gfn_t gfn;
/* Check the guest TLB. */
gtlbe = kvmppc_44x_dtlb_search(vcpu, eaddr);
if (!gtlbe) {
/* The guest didn't have a mapping for it. */
kvmppc_queue_exception(vcpu, exit_nr);
vcpu->arch.dear = vcpu->arch.fault_dear;
vcpu->arch.esr = vcpu->arch.fault_esr;
vcpu->stat.dtlb_real_miss_exits++;
r = RESUME_GUEST;
break;
}
vcpu->arch.paddr_accessed = tlb_xlate(gtlbe, eaddr);
gfn = vcpu->arch.paddr_accessed >> PAGE_SHIFT;
if (kvm_is_visible_gfn(vcpu->kvm, gfn)) {
/* The guest TLB had a mapping, but the shadow TLB
* didn't, and it is RAM. This could be because:
* a) the entry is mapping the host kernel, or
* b) the guest used a large mapping which we're faking
* Either way, we need to satisfy the fault without
* invoking the guest. */
kvmppc_mmu_map(vcpu, eaddr, gfn, gtlbe->tid,
gtlbe->word2);
vcpu->stat.dtlb_virt_miss_exits++;
r = RESUME_GUEST;
} else {
/* Guest has mapped and accessed a page which is not
* actually RAM. */
r = kvmppc_emulate_mmio(run, vcpu);
}
break;
}
case BOOKE_INTERRUPT_ITLB_MISS: {
struct tlbe *gtlbe;
unsigned long eaddr = vcpu->arch.pc;
gfn_t gfn;
r = RESUME_GUEST;
/* Check the guest TLB. */
gtlbe = kvmppc_44x_itlb_search(vcpu, eaddr);
if (!gtlbe) {
/* The guest didn't have a mapping for it. */
kvmppc_queue_exception(vcpu, exit_nr);
vcpu->stat.itlb_real_miss_exits++;
break;
}
vcpu->stat.itlb_virt_miss_exits++;
gfn = tlb_xlate(gtlbe, eaddr) >> PAGE_SHIFT;
if (kvm_is_visible_gfn(vcpu->kvm, gfn)) {
/* The guest TLB had a mapping, but the shadow TLB
* didn't. This could be because:
* a) the entry is mapping the host kernel, or
* b) the guest used a large mapping which we're faking
* Either way, we need to satisfy the fault without
* invoking the guest. */
kvmppc_mmu_map(vcpu, eaddr, gfn, gtlbe->tid,
gtlbe->word2);
} else {
/* Guest mapped and leaped at non-RAM! */
kvmppc_queue_exception(vcpu,
BOOKE_INTERRUPT_MACHINE_CHECK);
}
break;
}
default:
printk(KERN_EMERG "exit_nr %d\n", exit_nr);
BUG();
}
local_irq_disable();
kvmppc_check_and_deliver_interrupts(vcpu);
/* Do some exit accounting. */
vcpu->stat.sum_exits++;
if (!(r & RESUME_HOST)) {
/* To avoid clobbering exit_reason, only check for signals if
* we aren't already exiting to userspace for some other
* reason. */
if (signal_pending(current)) {
run->exit_reason = KVM_EXIT_INTR;
r = (-EINTR << 2) | RESUME_HOST | (r & RESUME_FLAG_NV);
vcpu->stat.signal_exits++;
} else {
vcpu->stat.light_exits++;
}
} else {
switch (run->exit_reason) {
case KVM_EXIT_MMIO:
vcpu->stat.mmio_exits++;
break;
case KVM_EXIT_DCR:
vcpu->stat.dcr_exits++;
break;
case KVM_EXIT_INTR:
vcpu->stat.signal_exits++;
break;
}
}
return r;
}
/* Initial guest state: 16MB mapping 0 -> 0, PC = 0, MSR = 0, R1 = 16MB */
int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
{
struct tlbe *tlbe = &vcpu->arch.guest_tlb[0];
tlbe->tid = 0;
tlbe->word0 = PPC44x_TLB_16M | PPC44x_TLB_VALID;
tlbe->word1 = 0;
tlbe->word2 = PPC44x_TLB_SX | PPC44x_TLB_SW | PPC44x_TLB_SR;
tlbe++;
tlbe->tid = 0;
tlbe->word0 = 0xef600000 | PPC44x_TLB_4K | PPC44x_TLB_VALID;
tlbe->word1 = 0xef600000;
tlbe->word2 = PPC44x_TLB_SX | PPC44x_TLB_SW | PPC44x_TLB_SR
| PPC44x_TLB_I | PPC44x_TLB_G;
vcpu->arch.pc = 0;
vcpu->arch.msr = 0;
vcpu->arch.gpr[1] = (16<<20) - 8; /* -8 for the callee-save LR slot */
/* Eye-catching number so we know if the guest takes an interrupt
* before it's programmed its own IVPR. */
vcpu->arch.ivpr = 0x55550000;
/* Since the guest can directly access the timebase, it must know the
* real timebase frequency. Accordingly, it must see the state of
* CCR1[TCS]. */
vcpu->arch.ccr1 = mfspr(SPRN_CCR1);
return 0;
}
int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
int i;
regs->pc = vcpu->arch.pc;
regs->cr = vcpu->arch.cr;
regs->ctr = vcpu->arch.ctr;
regs->lr = vcpu->arch.lr;
regs->xer = vcpu->arch.xer;
regs->msr = vcpu->arch.msr;
regs->srr0 = vcpu->arch.srr0;
regs->srr1 = vcpu->arch.srr1;
regs->pid = vcpu->arch.pid;
regs->sprg0 = vcpu->arch.sprg0;
regs->sprg1 = vcpu->arch.sprg1;
regs->sprg2 = vcpu->arch.sprg2;
regs->sprg3 = vcpu->arch.sprg3;
regs->sprg5 = vcpu->arch.sprg4;
regs->sprg6 = vcpu->arch.sprg5;
regs->sprg7 = vcpu->arch.sprg6;
for (i = 0; i < ARRAY_SIZE(regs->gpr); i++)
regs->gpr[i] = vcpu->arch.gpr[i];
return 0;
}
int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
int i;
vcpu->arch.pc = regs->pc;
vcpu->arch.cr = regs->cr;
vcpu->arch.ctr = regs->ctr;
vcpu->arch.lr = regs->lr;
vcpu->arch.xer = regs->xer;
vcpu->arch.msr = regs->msr;
vcpu->arch.srr0 = regs->srr0;
vcpu->arch.srr1 = regs->srr1;
vcpu->arch.sprg0 = regs->sprg0;
vcpu->arch.sprg1 = regs->sprg1;
vcpu->arch.sprg2 = regs->sprg2;
vcpu->arch.sprg3 = regs->sprg3;
vcpu->arch.sprg5 = regs->sprg4;
vcpu->arch.sprg6 = regs->sprg5;
vcpu->arch.sprg7 = regs->sprg6;
for (i = 0; i < ARRAY_SIZE(vcpu->arch.gpr); i++)
vcpu->arch.gpr[i] = regs->gpr[i];
return 0;
}
int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
struct kvm_sregs *sregs)
{
return -ENOTSUPP;
}
int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
struct kvm_sregs *sregs)
{
return -ENOTSUPP;
}
int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
return -ENOTSUPP;
}
int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
{
return -ENOTSUPP;
}
/* 'linear_address' is actually an encoding of AS|PID|EADDR . */
int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
struct kvm_translation *tr)
{
struct tlbe *gtlbe;
int index;
gva_t eaddr;
u8 pid;
u8 as;
eaddr = tr->linear_address;
pid = (tr->linear_address >> 32) & 0xff;
as = (tr->linear_address >> 40) & 0x1;
index = kvmppc_44x_tlb_index(vcpu, eaddr, pid, as);
if (index == -1) {
tr->valid = 0;
return 0;
}
gtlbe = &vcpu->arch.guest_tlb[index];
tr->physical_address = tlb_xlate(gtlbe, eaddr);
/* XXX what does "writeable" and "usermode" even mean? */
tr->valid = 1;
return 0;
}
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