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qemu-e2k/target/i386/monitor.c
Thomas Huth 854e67fea6 monitor: Fix crashes when using HMP commands without CPU 
When running certain HMP commands ("info registers", "info cpustats",
"info tlb", "nmi", "memsave" or dumping virtual memory) with the "none"
machine, QEMU crashes with a segmentation fault. This happens because the
"none" machine does not have any CPUs by default, but these HMP commands
did not check for a valid CPU pointer yet. Add such checks now, so we get
an error message about the missing CPU instead.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <1484309555-1935-1-git-send-email-thuth@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-02-21 18:29:01 +00:00

654 lines
23 KiB
C
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/*
* QEMU monitor
*
* Copyright (c) 2003-2004 Fabrice Bellard
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "cpu.h"
#include "monitor/monitor.h"
#include "monitor/hmp-target.h"
#include "hw/i386/pc.h"
#include "sysemu/kvm.h"
#include "hmp.h"
static void print_pte(Monitor *mon, CPUArchState *env, hwaddr addr,
hwaddr pte, hwaddr mask)
{
#ifdef TARGET_X86_64
if (env->cr[4] & CR4_LA57_MASK) {
if (addr & (1ULL << 56)) {
addr |= -1LL << 57;
}
} else {
if (addr & (1ULL << 47)) {
addr |= -1LL << 48;
}
}
#endif
monitor_printf(mon, TARGET_FMT_plx ": " TARGET_FMT_plx
" %c%c%c%c%c%c%c%c%c\n",
addr,
pte & mask,
pte & PG_NX_MASK ? 'X' : '-',
pte & PG_GLOBAL_MASK ? 'G' : '-',
pte & PG_PSE_MASK ? 'P' : '-',
pte & PG_DIRTY_MASK ? 'D' : '-',
pte & PG_ACCESSED_MASK ? 'A' : '-',
pte & PG_PCD_MASK ? 'C' : '-',
pte & PG_PWT_MASK ? 'T' : '-',
pte & PG_USER_MASK ? 'U' : '-',
pte & PG_RW_MASK ? 'W' : '-');
}
static void tlb_info_32(Monitor *mon, CPUArchState *env)
{
unsigned int l1, l2;
uint32_t pgd, pde, pte;
pgd = env->cr[3] & ~0xfff;
for(l1 = 0; l1 < 1024; l1++) {
cpu_physical_memory_read(pgd + l1 * 4, &pde, 4);
pde = le32_to_cpu(pde);
if (pde & PG_PRESENT_MASK) {
if ((pde & PG_PSE_MASK) && (env->cr[4] & CR4_PSE_MASK)) {
/* 4M pages */
print_pte(mon, env, (l1 << 22), pde, ~((1 << 21) - 1));
} else {
for(l2 = 0; l2 < 1024; l2++) {
cpu_physical_memory_read((pde & ~0xfff) + l2 * 4, &pte, 4);
pte = le32_to_cpu(pte);
if (pte & PG_PRESENT_MASK) {
print_pte(mon, env, (l1 << 22) + (l2 << 12),
pte & ~PG_PSE_MASK,
~0xfff);
}
}
}
}
}
}
static void tlb_info_pae32(Monitor *mon, CPUArchState *env)
{
unsigned int l1, l2, l3;
uint64_t pdpe, pde, pte;
uint64_t pdp_addr, pd_addr, pt_addr;
pdp_addr = env->cr[3] & ~0x1f;
for (l1 = 0; l1 < 4; l1++) {
cpu_physical_memory_read(pdp_addr + l1 * 8, &pdpe, 8);
pdpe = le64_to_cpu(pdpe);
if (pdpe & PG_PRESENT_MASK) {
pd_addr = pdpe & 0x3fffffffff000ULL;
for (l2 = 0; l2 < 512; l2++) {
cpu_physical_memory_read(pd_addr + l2 * 8, &pde, 8);
pde = le64_to_cpu(pde);
if (pde & PG_PRESENT_MASK) {
if (pde & PG_PSE_MASK) {
/* 2M pages with PAE, CR4.PSE is ignored */
print_pte(mon, env, (l1 << 30) + (l2 << 21), pde,
~((hwaddr)(1 << 20) - 1));
} else {
pt_addr = pde & 0x3fffffffff000ULL;
for (l3 = 0; l3 < 512; l3++) {
cpu_physical_memory_read(pt_addr + l3 * 8, &pte, 8);
pte = le64_to_cpu(pte);
if (pte & PG_PRESENT_MASK) {
print_pte(mon, env, (l1 << 30) + (l2 << 21)
+ (l3 << 12),
pte & ~PG_PSE_MASK,
~(hwaddr)0xfff);
}
}
}
}
}
}
}
}
#ifdef TARGET_X86_64
static void tlb_info_la48(Monitor *mon, CPUArchState *env,
uint64_t l0, uint64_t pml4_addr)
{
uint64_t l1, l2, l3, l4;
uint64_t pml4e, pdpe, pde, pte;
uint64_t pdp_addr, pd_addr, pt_addr;
for (l1 = 0; l1 < 512; l1++) {
cpu_physical_memory_read(pml4_addr + l1 * 8, &pml4e, 8);
pml4e = le64_to_cpu(pml4e);
if (!(pml4e & PG_PRESENT_MASK)) {
continue;
}
pdp_addr = pml4e & 0x3fffffffff000ULL;
for (l2 = 0; l2 < 512; l2++) {
cpu_physical_memory_read(pdp_addr + l2 * 8, &pdpe, 8);
pdpe = le64_to_cpu(pdpe);
if (!(pdpe & PG_PRESENT_MASK)) {
continue;
}
if (pdpe & PG_PSE_MASK) {
/* 1G pages, CR4.PSE is ignored */
print_pte(mon, env, (l0 << 48) + (l1 << 39) + (l2 << 30),
pdpe, 0x3ffffc0000000ULL);
continue;
}
pd_addr = pdpe & 0x3fffffffff000ULL;
for (l3 = 0; l3 < 512; l3++) {
cpu_physical_memory_read(pd_addr + l3 * 8, &pde, 8);
pde = le64_to_cpu(pde);
if (!(pde & PG_PRESENT_MASK)) {
continue;
}
if (pde & PG_PSE_MASK) {
/* 2M pages, CR4.PSE is ignored */
print_pte(mon, env, (l0 << 48) + (l1 << 39) + (l2 << 30) +
(l3 << 21), pde, 0x3ffffffe00000ULL);
continue;
}
pt_addr = pde & 0x3fffffffff000ULL;
for (l4 = 0; l4 < 512; l4++) {
cpu_physical_memory_read(pt_addr
+ l4 * 8,
&pte, 8);
pte = le64_to_cpu(pte);
if (pte & PG_PRESENT_MASK) {
print_pte(mon, env, (l0 << 48) + (l1 << 39) +
(l2 << 30) + (l3 << 21) + (l4 << 12),
pte & ~PG_PSE_MASK, 0x3fffffffff000ULL);
}
}
}
}
}
}
static void tlb_info_la57(Monitor *mon, CPUArchState *env)
{
uint64_t l0;
uint64_t pml5e;
uint64_t pml5_addr;
pml5_addr = env->cr[3] & 0x3fffffffff000ULL;
for (l0 = 0; l0 < 512; l0++) {
cpu_physical_memory_read(pml5_addr + l0 * 8, &pml5e, 8);
pml5e = le64_to_cpu(pml5e);
if (pml5e & PG_PRESENT_MASK) {
tlb_info_la48(mon, env, l0, pml5e & 0x3fffffffff000ULL);
}
}
}
#endif /* TARGET_X86_64 */
void hmp_info_tlb(Monitor *mon, const QDict *qdict)
{
CPUArchState *env;
env = mon_get_cpu_env();
if (!env) {
monitor_printf(mon, "No CPU available\n");
return;
}
if (!(env->cr[0] & CR0_PG_MASK)) {
monitor_printf(mon, "PG disabled\n");
return;
}
if (env->cr[4] & CR4_PAE_MASK) {
#ifdef TARGET_X86_64
if (env->hflags & HF_LMA_MASK) {
if (env->cr[4] & CR4_LA57_MASK) {
tlb_info_la57(mon, env);
} else {
tlb_info_la48(mon, env, 0, env->cr[3] & 0x3fffffffff000ULL);
}
} else
#endif
{
tlb_info_pae32(mon, env);
}
} else {
tlb_info_32(mon, env);
}
}
static void mem_print(Monitor *mon, hwaddr *pstart,
int *plast_prot,
hwaddr end, int prot)
{
int prot1;
prot1 = *plast_prot;
if (prot != prot1) {
if (*pstart != -1) {
monitor_printf(mon, TARGET_FMT_plx "-" TARGET_FMT_plx " "
TARGET_FMT_plx " %c%c%c\n",
*pstart, end, end - *pstart,
prot1 & PG_USER_MASK ? 'u' : '-',
'r',
prot1 & PG_RW_MASK ? 'w' : '-');
}
if (prot != 0)
*pstart = end;
else
*pstart = -1;
*plast_prot = prot;
}
}
static void mem_info_32(Monitor *mon, CPUArchState *env)
{
unsigned int l1, l2;
int prot, last_prot;
uint32_t pgd, pde, pte;
hwaddr start, end;
pgd = env->cr[3] & ~0xfff;
last_prot = 0;
start = -1;
for(l1 = 0; l1 < 1024; l1++) {
cpu_physical_memory_read(pgd + l1 * 4, &pde, 4);
pde = le32_to_cpu(pde);
end = l1 << 22;
if (pde & PG_PRESENT_MASK) {
if ((pde & PG_PSE_MASK) && (env->cr[4] & CR4_PSE_MASK)) {
prot = pde & (PG_USER_MASK | PG_RW_MASK | PG_PRESENT_MASK);
mem_print(mon, &start, &last_prot, end, prot);
} else {
for(l2 = 0; l2 < 1024; l2++) {
cpu_physical_memory_read((pde & ~0xfff) + l2 * 4, &pte, 4);
pte = le32_to_cpu(pte);
end = (l1 << 22) + (l2 << 12);
if (pte & PG_PRESENT_MASK) {
prot = pte & pde &
(PG_USER_MASK | PG_RW_MASK | PG_PRESENT_MASK);
} else {
prot = 0;
}
mem_print(mon, &start, &last_prot, end, prot);
}
}
} else {
prot = 0;
mem_print(mon, &start, &last_prot, end, prot);
}
}
/* Flush last range */
mem_print(mon, &start, &last_prot, (hwaddr)1 << 32, 0);
}
static void mem_info_pae32(Monitor *mon, CPUArchState *env)
{
unsigned int l1, l2, l3;
int prot, last_prot;
uint64_t pdpe, pde, pte;
uint64_t pdp_addr, pd_addr, pt_addr;
hwaddr start, end;
pdp_addr = env->cr[3] & ~0x1f;
last_prot = 0;
start = -1;
for (l1 = 0; l1 < 4; l1++) {
cpu_physical_memory_read(pdp_addr + l1 * 8, &pdpe, 8);
pdpe = le64_to_cpu(pdpe);
end = l1 << 30;
if (pdpe & PG_PRESENT_MASK) {
pd_addr = pdpe & 0x3fffffffff000ULL;
for (l2 = 0; l2 < 512; l2++) {
cpu_physical_memory_read(pd_addr + l2 * 8, &pde, 8);
pde = le64_to_cpu(pde);
end = (l1 << 30) + (l2 << 21);
if (pde & PG_PRESENT_MASK) {
if (pde & PG_PSE_MASK) {
prot = pde & (PG_USER_MASK | PG_RW_MASK |
PG_PRESENT_MASK);
mem_print(mon, &start, &last_prot, end, prot);
} else {
pt_addr = pde & 0x3fffffffff000ULL;
for (l3 = 0; l3 < 512; l3++) {
cpu_physical_memory_read(pt_addr + l3 * 8, &pte, 8);
pte = le64_to_cpu(pte);
end = (l1 << 30) + (l2 << 21) + (l3 << 12);
if (pte & PG_PRESENT_MASK) {
prot = pte & pde & (PG_USER_MASK | PG_RW_MASK |
PG_PRESENT_MASK);
} else {
prot = 0;
}
mem_print(mon, &start, &last_prot, end, prot);
}
}
} else {
prot = 0;
mem_print(mon, &start, &last_prot, end, prot);
}
}
} else {
prot = 0;
mem_print(mon, &start, &last_prot, end, prot);
}
}
/* Flush last range */
mem_print(mon, &start, &last_prot, (hwaddr)1 << 32, 0);
}
#ifdef TARGET_X86_64
static void mem_info_la48(Monitor *mon, CPUArchState *env)
{
int prot, last_prot;
uint64_t l1, l2, l3, l4;
uint64_t pml4e, pdpe, pde, pte;
uint64_t pml4_addr, pdp_addr, pd_addr, pt_addr, start, end;
pml4_addr = env->cr[3] & 0x3fffffffff000ULL;
last_prot = 0;
start = -1;
for (l1 = 0; l1 < 512; l1++) {
cpu_physical_memory_read(pml4_addr + l1 * 8, &pml4e, 8);
pml4e = le64_to_cpu(pml4e);
end = l1 << 39;
if (pml4e & PG_PRESENT_MASK) {
pdp_addr = pml4e & 0x3fffffffff000ULL;
for (l2 = 0; l2 < 512; l2++) {
cpu_physical_memory_read(pdp_addr + l2 * 8, &pdpe, 8);
pdpe = le64_to_cpu(pdpe);
end = (l1 << 39) + (l2 << 30);
if (pdpe & PG_PRESENT_MASK) {
if (pdpe & PG_PSE_MASK) {
prot = pdpe & (PG_USER_MASK | PG_RW_MASK |
PG_PRESENT_MASK);
prot &= pml4e;
mem_print(mon, &start, &last_prot, end, prot);
} else {
pd_addr = pdpe & 0x3fffffffff000ULL;
for (l3 = 0; l3 < 512; l3++) {
cpu_physical_memory_read(pd_addr + l3 * 8, &pde, 8);
pde = le64_to_cpu(pde);
end = (l1 << 39) + (l2 << 30) + (l3 << 21);
if (pde & PG_PRESENT_MASK) {
if (pde & PG_PSE_MASK) {
prot = pde & (PG_USER_MASK | PG_RW_MASK |
PG_PRESENT_MASK);
prot &= pml4e & pdpe;
mem_print(mon, &start, &last_prot, end, prot);
} else {
pt_addr = pde & 0x3fffffffff000ULL;
for (l4 = 0; l4 < 512; l4++) {
cpu_physical_memory_read(pt_addr
+ l4 * 8,
&pte, 8);
pte = le64_to_cpu(pte);
end = (l1 << 39) + (l2 << 30) +
(l3 << 21) + (l4 << 12);
if (pte & PG_PRESENT_MASK) {
prot = pte & (PG_USER_MASK | PG_RW_MASK |
PG_PRESENT_MASK);
prot &= pml4e & pdpe & pde;
} else {
prot = 0;
}
mem_print(mon, &start, &last_prot, end, prot);
}
}
} else {
prot = 0;
mem_print(mon, &start, &last_prot, end, prot);
}
}
}
} else {
prot = 0;
mem_print(mon, &start, &last_prot, end, prot);
}
}
} else {
prot = 0;
mem_print(mon, &start, &last_prot, end, prot);
}
}
/* Flush last range */
mem_print(mon, &start, &last_prot, (hwaddr)1 << 48, 0);
}
static void mem_info_la57(Monitor *mon, CPUArchState *env)
{
int prot, last_prot;
uint64_t l0, l1, l2, l3, l4;
uint64_t pml5e, pml4e, pdpe, pde, pte;
uint64_t pml5_addr, pml4_addr, pdp_addr, pd_addr, pt_addr, start, end;
pml5_addr = env->cr[3] & 0x3fffffffff000ULL;
last_prot = 0;
start = -1;
for (l0 = 0; l0 < 512; l0++) {
cpu_physical_memory_read(pml5_addr + l0 * 8, &pml5e, 8);
pml4e = le64_to_cpu(pml5e);
end = l0 << 48;
if (!(pml5e & PG_PRESENT_MASK)) {
prot = 0;
mem_print(mon, &start, &last_prot, end, prot);
continue;
}
pml4_addr = pml5e & 0x3fffffffff000ULL;
for (l1 = 0; l1 < 512; l1++) {
cpu_physical_memory_read(pml4_addr + l1 * 8, &pml4e, 8);
pml4e = le64_to_cpu(pml4e);
end = (l0 << 48) + (l1 << 39);
if (!(pml4e & PG_PRESENT_MASK)) {
prot = 0;
mem_print(mon, &start, &last_prot, end, prot);
continue;
}
pdp_addr = pml4e & 0x3fffffffff000ULL;
for (l2 = 0; l2 < 512; l2++) {
cpu_physical_memory_read(pdp_addr + l2 * 8, &pdpe, 8);
pdpe = le64_to_cpu(pdpe);
end = (l0 << 48) + (l1 << 39) + (l2 << 30);
if (pdpe & PG_PRESENT_MASK) {
prot = 0;
mem_print(mon, &start, &last_prot, end, prot);
continue;
}
if (pdpe & PG_PSE_MASK) {
prot = pdpe & (PG_USER_MASK | PG_RW_MASK |
PG_PRESENT_MASK);
prot &= pml4e;
mem_print(mon, &start, &last_prot, end, prot);
continue;
}
pd_addr = pdpe & 0x3fffffffff000ULL;
for (l3 = 0; l3 < 512; l3++) {
cpu_physical_memory_read(pd_addr + l3 * 8, &pde, 8);
pde = le64_to_cpu(pde);
end = (l0 << 48) + (l1 << 39) + (l2 << 30) + (l3 << 21);
if (pde & PG_PRESENT_MASK) {
prot = 0;
mem_print(mon, &start, &last_prot, end, prot);
continue;
}
if (pde & PG_PSE_MASK) {
prot = pde & (PG_USER_MASK | PG_RW_MASK |
PG_PRESENT_MASK);
prot &= pml4e & pdpe;
mem_print(mon, &start, &last_prot, end, prot);
continue;
}
pt_addr = pde & 0x3fffffffff000ULL;
for (l4 = 0; l4 < 512; l4++) {
cpu_physical_memory_read(pt_addr + l4 * 8, &pte, 8);
pte = le64_to_cpu(pte);
end = (l0 << 48) + (l1 << 39) + (l2 << 30) +
(l3 << 21) + (l4 << 12);
if (pte & PG_PRESENT_MASK) {
prot = pte & (PG_USER_MASK | PG_RW_MASK |
PG_PRESENT_MASK);
prot &= pml4e & pdpe & pde;
} else {
prot = 0;
}
mem_print(mon, &start, &last_prot, end, prot);
}
}
}
}
}
/* Flush last range */
mem_print(mon, &start, &last_prot, (hwaddr)1 << 57, 0);
}
#endif /* TARGET_X86_64 */
void hmp_info_mem(Monitor *mon, const QDict *qdict)
{
CPUArchState *env;
env = mon_get_cpu_env();
if (!env) {
monitor_printf(mon, "No CPU available\n");
return;
}
if (!(env->cr[0] & CR0_PG_MASK)) {
monitor_printf(mon, "PG disabled\n");
return;
}
if (env->cr[4] & CR4_PAE_MASK) {
#ifdef TARGET_X86_64
if (env->hflags & HF_LMA_MASK) {
if (env->cr[4] & CR4_LA57_MASK) {
mem_info_la57(mon, env);
} else {
mem_info_la48(mon, env);
}
} else
#endif
{
mem_info_pae32(mon, env);
}
} else {
mem_info_32(mon, env);
}
}
void hmp_mce(Monitor *mon, const QDict *qdict)
{
X86CPU *cpu;
CPUState *cs;
int cpu_index = qdict_get_int(qdict, "cpu_index");
int bank = qdict_get_int(qdict, "bank");
uint64_t status = qdict_get_int(qdict, "status");
uint64_t mcg_status = qdict_get_int(qdict, "mcg_status");
uint64_t addr = qdict_get_int(qdict, "addr");
uint64_t misc = qdict_get_int(qdict, "misc");
int flags = MCE_INJECT_UNCOND_AO;
if (qdict_get_try_bool(qdict, "broadcast", false)) {
flags |= MCE_INJECT_BROADCAST;
}
cs = qemu_get_cpu(cpu_index);
if (cs != NULL) {
cpu = X86_CPU(cs);
cpu_x86_inject_mce(mon, cpu, bank, status, mcg_status, addr, misc,
flags);
}
}
static target_long monitor_get_pc(const struct MonitorDef *md, int val)
{
CPUArchState *env = mon_get_cpu_env();
return env->eip + env->segs[R_CS].base;
}
const MonitorDef monitor_defs[] = {
#define SEG(name, seg) \
{ name, offsetof(CPUX86State, segs[seg].selector), NULL, MD_I32 },\
{ name ".base", offsetof(CPUX86State, segs[seg].base) },\
{ name ".limit", offsetof(CPUX86State, segs[seg].limit), NULL, MD_I32 },
{ "eax", offsetof(CPUX86State, regs[0]) },
{ "ecx", offsetof(CPUX86State, regs[1]) },
{ "edx", offsetof(CPUX86State, regs[2]) },
{ "ebx", offsetof(CPUX86State, regs[3]) },
{ "esp|sp", offsetof(CPUX86State, regs[4]) },
{ "ebp|fp", offsetof(CPUX86State, regs[5]) },
{ "esi", offsetof(CPUX86State, regs[6]) },
{ "edi", offsetof(CPUX86State, regs[7]) },
#ifdef TARGET_X86_64
{ "r8", offsetof(CPUX86State, regs[8]) },
{ "r9", offsetof(CPUX86State, regs[9]) },
{ "r10", offsetof(CPUX86State, regs[10]) },
{ "r11", offsetof(CPUX86State, regs[11]) },
{ "r12", offsetof(CPUX86State, regs[12]) },
{ "r13", offsetof(CPUX86State, regs[13]) },
{ "r14", offsetof(CPUX86State, regs[14]) },
{ "r15", offsetof(CPUX86State, regs[15]) },
#endif
{ "eflags", offsetof(CPUX86State, eflags) },
{ "eip", offsetof(CPUX86State, eip) },
SEG("cs", R_CS)
SEG("ds", R_DS)
SEG("es", R_ES)
SEG("ss", R_SS)
SEG("fs", R_FS)
SEG("gs", R_GS)
{ "pc", 0, monitor_get_pc, },
{ NULL },
};
const MonitorDef *target_monitor_defs(void)
{
return monitor_defs;
}
void hmp_info_local_apic(Monitor *mon, const QDict *qdict)
{
CPUState *cs = mon_get_cpu();
if (!cs) {
monitor_printf(mon, "No CPU available\n");
return;
}
x86_cpu_dump_local_apic_state(cs, (FILE *)mon, monitor_fprintf,
CPU_DUMP_FPU);
}
void hmp_info_io_apic(Monitor *mon, const QDict *qdict)
{
if (kvm_irqchip_in_kernel() &&
!kvm_irqchip_is_split()) {
kvm_ioapic_dump_state(mon, qdict);
} else {
ioapic_dump_state(mon, qdict);
}
}
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