Commit 80132f4c authored by Radim Krčmář's avatar Radim Krčmář

Merge branch 'msr-bitmaps' of git://git.kernel.org/pub/scm/virt/kvm/kvm

This topic branch allocates separate MSR bitmaps for each VCPU.
This is required for the IBRS enablement to choose, on a per-VM
basis, whether to intercept the SPEC_CTRL and PRED_CMD MSRs;
the IBRS enablement comes in through the tip tree.
parents 8dbfb2bf 904e14fb
......@@ -111,6 +111,14 @@ static u64 __read_mostly host_xss;
static bool __read_mostly enable_pml = 1;
module_param_named(pml, enable_pml, bool, S_IRUGO);
#define MSR_TYPE_R 1
#define MSR_TYPE_W 2
#define MSR_TYPE_RW 3
#define MSR_BITMAP_MODE_X2APIC 1
#define MSR_BITMAP_MODE_X2APIC_APICV 2
#define MSR_BITMAP_MODE_LM 4
#define KVM_VMX_TSC_MULTIPLIER_MAX 0xffffffffffffffffULL
/* Guest_tsc -> host_tsc conversion requires 64-bit division. */
......@@ -209,6 +217,7 @@ struct loaded_vmcs {
int soft_vnmi_blocked;
ktime_t entry_time;
s64 vnmi_blocked_time;
unsigned long *msr_bitmap;
struct list_head loaded_vmcss_on_cpu_link;
};
......@@ -456,8 +465,6 @@ struct nested_vmx {
bool pi_pending;
u16 posted_intr_nv;
unsigned long *msr_bitmap;
struct hrtimer preemption_timer;
bool preemption_timer_expired;
......@@ -580,6 +587,7 @@ struct vcpu_vmx {
struct kvm_vcpu vcpu;
unsigned long host_rsp;
u8 fail;
u8 msr_bitmap_mode;
u32 exit_intr_info;
u32 idt_vectoring_info;
ulong rflags;
......@@ -897,6 +905,7 @@ static bool vmx_get_nmi_mask(struct kvm_vcpu *vcpu);
static void vmx_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked);
static bool nested_vmx_is_page_fault_vmexit(struct vmcs12 *vmcs12,
u16 error_code);
static void vmx_update_msr_bitmap(struct kvm_vcpu *vcpu);
static DEFINE_PER_CPU(struct vmcs *, vmxarea);
static DEFINE_PER_CPU(struct vmcs *, current_vmcs);
......@@ -914,12 +923,6 @@ static DEFINE_PER_CPU(struct list_head, blocked_vcpu_on_cpu);
static DEFINE_PER_CPU(spinlock_t, blocked_vcpu_on_cpu_lock);
enum {
VMX_MSR_BITMAP_LEGACY,
VMX_MSR_BITMAP_LONGMODE,
VMX_MSR_BITMAP_LEGACY_X2APIC_APICV,
VMX_MSR_BITMAP_LONGMODE_X2APIC_APICV,
VMX_MSR_BITMAP_LEGACY_X2APIC,
VMX_MSR_BITMAP_LONGMODE_X2APIC,
VMX_VMREAD_BITMAP,
VMX_VMWRITE_BITMAP,
VMX_BITMAP_NR
......@@ -927,12 +930,6 @@ enum {
static unsigned long *vmx_bitmap[VMX_BITMAP_NR];
#define vmx_msr_bitmap_legacy (vmx_bitmap[VMX_MSR_BITMAP_LEGACY])
#define vmx_msr_bitmap_longmode (vmx_bitmap[VMX_MSR_BITMAP_LONGMODE])
#define vmx_msr_bitmap_legacy_x2apic_apicv (vmx_bitmap[VMX_MSR_BITMAP_LEGACY_X2APIC_APICV])
#define vmx_msr_bitmap_longmode_x2apic_apicv (vmx_bitmap[VMX_MSR_BITMAP_LONGMODE_X2APIC_APICV])
#define vmx_msr_bitmap_legacy_x2apic (vmx_bitmap[VMX_MSR_BITMAP_LEGACY_X2APIC])
#define vmx_msr_bitmap_longmode_x2apic (vmx_bitmap[VMX_MSR_BITMAP_LONGMODE_X2APIC])
#define vmx_vmread_bitmap (vmx_bitmap[VMX_VMREAD_BITMAP])
#define vmx_vmwrite_bitmap (vmx_bitmap[VMX_VMWRITE_BITMAP])
......@@ -2531,36 +2528,6 @@ static void move_msr_up(struct vcpu_vmx *vmx, int from, int to)
vmx->guest_msrs[from] = tmp;
}
static void vmx_set_msr_bitmap(struct kvm_vcpu *vcpu)
{
unsigned long *msr_bitmap;
if (is_guest_mode(vcpu))
msr_bitmap = to_vmx(vcpu)->nested.msr_bitmap;
else if (cpu_has_secondary_exec_ctrls() &&
(vmcs_read32(SECONDARY_VM_EXEC_CONTROL) &
SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE)) {
if (enable_apicv && kvm_vcpu_apicv_active(vcpu)) {
if (is_long_mode(vcpu))
msr_bitmap = vmx_msr_bitmap_longmode_x2apic_apicv;
else
msr_bitmap = vmx_msr_bitmap_legacy_x2apic_apicv;
} else {
if (is_long_mode(vcpu))
msr_bitmap = vmx_msr_bitmap_longmode_x2apic;
else
msr_bitmap = vmx_msr_bitmap_legacy_x2apic;
}
} else {
if (is_long_mode(vcpu))
msr_bitmap = vmx_msr_bitmap_longmode;
else
msr_bitmap = vmx_msr_bitmap_legacy;
}
vmcs_write64(MSR_BITMAP, __pa(msr_bitmap));
}
/*
* Set up the vmcs to automatically save and restore system
* msrs. Don't touch the 64-bit msrs if the guest is in legacy
......@@ -2601,7 +2568,7 @@ static void setup_msrs(struct vcpu_vmx *vmx)
vmx->save_nmsrs = save_nmsrs;
if (cpu_has_vmx_msr_bitmap())
vmx_set_msr_bitmap(&vmx->vcpu);
vmx_update_msr_bitmap(&vmx->vcpu);
}
/*
......@@ -3798,11 +3765,6 @@ static struct vmcs *alloc_vmcs_cpu(int cpu)
return vmcs;
}
static struct vmcs *alloc_vmcs(void)
{
return alloc_vmcs_cpu(raw_smp_processor_id());
}
static void free_vmcs(struct vmcs *vmcs)
{
free_pages((unsigned long)vmcs, vmcs_config.order);
......@@ -3818,20 +3780,36 @@ static void free_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
loaded_vmcs_clear(loaded_vmcs);
free_vmcs(loaded_vmcs->vmcs);
loaded_vmcs->vmcs = NULL;
if (loaded_vmcs->msr_bitmap)
free_page((unsigned long)loaded_vmcs->msr_bitmap);
WARN_ON(loaded_vmcs->shadow_vmcs != NULL);
}
static void vmx_nested_free_vmcs02(struct vcpu_vmx *vmx)
static struct vmcs *alloc_vmcs(void)
{
struct loaded_vmcs *loaded_vmcs = &vmx->nested.vmcs02;
return alloc_vmcs_cpu(raw_smp_processor_id());
}
/*
* Just leak the VMCS02 if the WARN triggers. Better than
* a use-after-free.
*/
if (WARN_ON(vmx->loaded_vmcs == loaded_vmcs))
return;
static int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
{
loaded_vmcs->vmcs = alloc_vmcs();
if (!loaded_vmcs->vmcs)
return -ENOMEM;
loaded_vmcs->shadow_vmcs = NULL;
loaded_vmcs_init(loaded_vmcs);
if (cpu_has_vmx_msr_bitmap()) {
loaded_vmcs->msr_bitmap = (unsigned long *)__get_free_page(GFP_KERNEL);
if (!loaded_vmcs->msr_bitmap)
goto out_vmcs;
memset(loaded_vmcs->msr_bitmap, 0xff, PAGE_SIZE);
}
return 0;
out_vmcs:
free_loaded_vmcs(loaded_vmcs);
return -ENOMEM;
}
static void free_kvm_area(void)
......@@ -4924,10 +4902,8 @@ static void free_vpid(int vpid)
spin_unlock(&vmx_vpid_lock);
}
#define MSR_TYPE_R 1
#define MSR_TYPE_W 2
static void __vmx_disable_intercept_for_msr(unsigned long *msr_bitmap,
u32 msr, int type)
static void __always_inline vmx_disable_intercept_for_msr(unsigned long *msr_bitmap,
u32 msr, int type)
{
int f = sizeof(unsigned long);
......@@ -4961,6 +4937,50 @@ static void __vmx_disable_intercept_for_msr(unsigned long *msr_bitmap,
}
}
static void __always_inline vmx_enable_intercept_for_msr(unsigned long *msr_bitmap,
u32 msr, int type)
{
int f = sizeof(unsigned long);
if (!cpu_has_vmx_msr_bitmap())
return;
/*
* See Intel PRM Vol. 3, 20.6.9 (MSR-Bitmap Address). Early manuals
* have the write-low and read-high bitmap offsets the wrong way round.
* We can control MSRs 0x00000000-0x00001fff and 0xc0000000-0xc0001fff.
*/
if (msr <= 0x1fff) {
if (type & MSR_TYPE_R)
/* read-low */
__set_bit(msr, msr_bitmap + 0x000 / f);
if (type & MSR_TYPE_W)
/* write-low */
__set_bit(msr, msr_bitmap + 0x800 / f);
} else if ((msr >= 0xc0000000) && (msr <= 0xc0001fff)) {
msr &= 0x1fff;
if (type & MSR_TYPE_R)
/* read-high */
__set_bit(msr, msr_bitmap + 0x400 / f);
if (type & MSR_TYPE_W)
/* write-high */
__set_bit(msr, msr_bitmap + 0xc00 / f);
}
}
static void __always_inline vmx_set_intercept_for_msr(unsigned long *msr_bitmap,
u32 msr, int type, bool value)
{
if (value)
vmx_enable_intercept_for_msr(msr_bitmap, msr, type);
else
vmx_disable_intercept_for_msr(msr_bitmap, msr, type);
}
/*
* If a msr is allowed by L0, we should check whether it is allowed by L1.
* The corresponding bit will be cleared unless both of L0 and L1 allow it.
......@@ -5002,31 +5022,70 @@ static void nested_vmx_disable_intercept_for_msr(unsigned long *msr_bitmap_l1,
}
}
static void vmx_disable_intercept_for_msr(u32 msr, bool longmode_only)
static u8 vmx_msr_bitmap_mode(struct kvm_vcpu *vcpu)
{
if (!longmode_only)
__vmx_disable_intercept_for_msr(vmx_msr_bitmap_legacy,
msr, MSR_TYPE_R | MSR_TYPE_W);
__vmx_disable_intercept_for_msr(vmx_msr_bitmap_longmode,
msr, MSR_TYPE_R | MSR_TYPE_W);
u8 mode = 0;
if (cpu_has_secondary_exec_ctrls() &&
(vmcs_read32(SECONDARY_VM_EXEC_CONTROL) &
SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE)) {
mode |= MSR_BITMAP_MODE_X2APIC;
if (enable_apicv && kvm_vcpu_apicv_active(vcpu))
mode |= MSR_BITMAP_MODE_X2APIC_APICV;
}
if (is_long_mode(vcpu))
mode |= MSR_BITMAP_MODE_LM;
return mode;
}
#define X2APIC_MSR(r) (APIC_BASE_MSR + ((r) >> 4))
static void vmx_disable_intercept_msr_x2apic(u32 msr, int type, bool apicv_only)
static void vmx_update_msr_bitmap_x2apic(unsigned long *msr_bitmap,
u8 mode)
{
__vmx_disable_intercept_for_msr(vmx_msr_bitmap_legacy_x2apic_apicv,
msr, type);
__vmx_disable_intercept_for_msr(vmx_msr_bitmap_longmode_x2apic_apicv,
msr, type);
if (!apicv_only) {
__vmx_disable_intercept_for_msr(vmx_msr_bitmap_legacy_x2apic,
msr, type);
__vmx_disable_intercept_for_msr(vmx_msr_bitmap_longmode_x2apic,
msr, type);
int msr;
for (msr = 0x800; msr <= 0x8ff; msr += BITS_PER_LONG) {
unsigned word = msr / BITS_PER_LONG;
msr_bitmap[word] = (mode & MSR_BITMAP_MODE_X2APIC_APICV) ? 0 : ~0;
msr_bitmap[word + (0x800 / sizeof(long))] = ~0;
}
if (mode & MSR_BITMAP_MODE_X2APIC) {
/*
* TPR reads and writes can be virtualized even if virtual interrupt
* delivery is not in use.
*/
vmx_disable_intercept_for_msr(msr_bitmap, X2APIC_MSR(APIC_TASKPRI), MSR_TYPE_RW);
if (mode & MSR_BITMAP_MODE_X2APIC_APICV) {
vmx_enable_intercept_for_msr(msr_bitmap, X2APIC_MSR(APIC_TMCCT), MSR_TYPE_R);
vmx_disable_intercept_for_msr(msr_bitmap, X2APIC_MSR(APIC_EOI), MSR_TYPE_W);
vmx_disable_intercept_for_msr(msr_bitmap, X2APIC_MSR(APIC_SELF_IPI), MSR_TYPE_W);
}
}
}
static void vmx_update_msr_bitmap(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
unsigned long *msr_bitmap = vmx->vmcs01.msr_bitmap;
u8 mode = vmx_msr_bitmap_mode(vcpu);
u8 changed = mode ^ vmx->msr_bitmap_mode;
if (!changed)
return;
vmx_set_intercept_for_msr(msr_bitmap, MSR_KERNEL_GS_BASE, MSR_TYPE_RW,
!(mode & MSR_BITMAP_MODE_LM));
if (changed & (MSR_BITMAP_MODE_X2APIC | MSR_BITMAP_MODE_X2APIC_APICV))
vmx_update_msr_bitmap_x2apic(msr_bitmap, mode);
vmx->msr_bitmap_mode = mode;
}
static bool vmx_get_enable_apicv(struct kvm_vcpu *vcpu)
{
return enable_apicv;
......@@ -5278,7 +5337,7 @@ static void vmx_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
}
if (cpu_has_vmx_msr_bitmap())
vmx_set_msr_bitmap(vcpu);
vmx_update_msr_bitmap(vcpu);
}
static u32 vmx_exec_control(struct vcpu_vmx *vmx)
......@@ -5467,7 +5526,7 @@ static void vmx_vcpu_setup(struct vcpu_vmx *vmx)
vmcs_write64(VMWRITE_BITMAP, __pa(vmx_vmwrite_bitmap));
}
if (cpu_has_vmx_msr_bitmap())
vmcs_write64(MSR_BITMAP, __pa(vmx_msr_bitmap_legacy));
vmcs_write64(MSR_BITMAP, __pa(vmx->vmcs01.msr_bitmap));
vmcs_write64(VMCS_LINK_POINTER, -1ull); /* 22.3.1.5 */
......@@ -6770,7 +6829,7 @@ void vmx_enable_tdp(void)
static __init int hardware_setup(void)
{
int r = -ENOMEM, i, msr;
int r = -ENOMEM, i;
rdmsrl_safe(MSR_EFER, &host_efer);
......@@ -6786,9 +6845,6 @@ static __init int hardware_setup(void)
memset(vmx_vmread_bitmap, 0xff, PAGE_SIZE);
memset(vmx_vmwrite_bitmap, 0xff, PAGE_SIZE);
memset(vmx_msr_bitmap_legacy, 0xff, PAGE_SIZE);
memset(vmx_msr_bitmap_longmode, 0xff, PAGE_SIZE);
if (setup_vmcs_config(&vmcs_config) < 0) {
r = -EIO;
goto out;
......@@ -6852,38 +6908,8 @@ static __init int hardware_setup(void)
kvm_tsc_scaling_ratio_frac_bits = 48;
}
vmx_disable_intercept_for_msr(MSR_FS_BASE, false);
vmx_disable_intercept_for_msr(MSR_GS_BASE, false);
vmx_disable_intercept_for_msr(MSR_KERNEL_GS_BASE, true);
vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_CS, false);
vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_ESP, false);
vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_EIP, false);
memcpy(vmx_msr_bitmap_legacy_x2apic_apicv,
vmx_msr_bitmap_legacy, PAGE_SIZE);
memcpy(vmx_msr_bitmap_longmode_x2apic_apicv,
vmx_msr_bitmap_longmode, PAGE_SIZE);
memcpy(vmx_msr_bitmap_legacy_x2apic,
vmx_msr_bitmap_legacy, PAGE_SIZE);
memcpy(vmx_msr_bitmap_longmode_x2apic,
vmx_msr_bitmap_longmode, PAGE_SIZE);
set_bit(0, vmx_vpid_bitmap); /* 0 is reserved for host */
for (msr = 0x800; msr <= 0x8ff; msr++) {
if (msr == X2APIC_MSR(APIC_TMCCT))
continue;
vmx_disable_intercept_msr_x2apic(msr, MSR_TYPE_R, true);
}
/*
* TPR reads and writes can be virtualized even if virtual interrupt
* delivery is not in use.
*/
vmx_disable_intercept_msr_x2apic(X2APIC_MSR(APIC_TASKPRI), MSR_TYPE_R | MSR_TYPE_W, false);
vmx_disable_intercept_msr_x2apic(X2APIC_MSR(APIC_EOI), MSR_TYPE_W, true);
vmx_disable_intercept_msr_x2apic(X2APIC_MSR(APIC_SELF_IPI), MSR_TYPE_W, true);
if (enable_ept)
vmx_enable_tdp();
else
......@@ -7171,20 +7197,11 @@ static int enter_vmx_operation(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
struct vmcs *shadow_vmcs;
int r;
vmx->nested.vmcs02.vmcs = alloc_vmcs();
vmx->nested.vmcs02.shadow_vmcs = NULL;
if (!vmx->nested.vmcs02.vmcs)
r = alloc_loaded_vmcs(&vmx->nested.vmcs02);
if (r < 0)
goto out_vmcs02;
loaded_vmcs_init(&vmx->nested.vmcs02);
if (cpu_has_vmx_msr_bitmap()) {
vmx->nested.msr_bitmap =
(unsigned long *)__get_free_page(GFP_KERNEL);
if (!vmx->nested.msr_bitmap)
goto out_msr_bitmap;
memset(vmx->nested.msr_bitmap, 0xff, PAGE_SIZE);
}
vmx->nested.cached_vmcs12 = kmalloc(VMCS12_SIZE, GFP_KERNEL);
if (!vmx->nested.cached_vmcs12)
......@@ -7212,10 +7229,7 @@ static int enter_vmx_operation(struct kvm_vcpu *vcpu)
kfree(vmx->nested.cached_vmcs12);
out_cached_vmcs12:
free_page((unsigned long)vmx->nested.msr_bitmap);
out_msr_bitmap:
vmx_nested_free_vmcs02(vmx);
free_loaded_vmcs(&vmx->nested.vmcs02);
out_vmcs02:
return -ENOMEM;
......@@ -7360,10 +7374,6 @@ static void free_nested(struct vcpu_vmx *vmx)
free_vpid(vmx->nested.vpid02);
vmx->nested.posted_intr_nv = -1;
vmx->nested.current_vmptr = -1ull;
if (vmx->nested.msr_bitmap) {
free_page((unsigned long)vmx->nested.msr_bitmap);
vmx->nested.msr_bitmap = NULL;
}
if (enable_shadow_vmcs) {
vmx_disable_shadow_vmcs(vmx);
vmcs_clear(vmx->vmcs01.shadow_vmcs);
......@@ -7387,7 +7397,7 @@ static void free_nested(struct vcpu_vmx *vmx)
vmx->nested.pi_desc = NULL;
}
vmx_nested_free_vmcs02(vmx);
free_loaded_vmcs(&vmx->nested.vmcs02);
}
/* Emulate the VMXOFF instruction */
......@@ -8865,7 +8875,7 @@ static void vmx_set_virtual_x2apic_mode(struct kvm_vcpu *vcpu, bool set)
}
vmcs_write32(SECONDARY_VM_EXEC_CONTROL, sec_exec_control);
vmx_set_msr_bitmap(vcpu);
vmx_update_msr_bitmap(vcpu);
}
static void vmx_set_apic_access_page_addr(struct kvm_vcpu *vcpu, hpa_t hpa)
......@@ -9532,6 +9542,7 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id)
{
int err;
struct vcpu_vmx *vmx = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
unsigned long *msr_bitmap;
int cpu;
if (!vmx)
......@@ -9564,13 +9575,20 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id)
if (!vmx->guest_msrs)
goto free_pml;
vmx->loaded_vmcs = &vmx->vmcs01;
vmx->loaded_vmcs->vmcs = alloc_vmcs();
vmx->loaded_vmcs->shadow_vmcs = NULL;
if (!vmx->loaded_vmcs->vmcs)
err = alloc_loaded_vmcs(&vmx->vmcs01);
if (err < 0)
goto free_msrs;
loaded_vmcs_init(vmx->loaded_vmcs);
msr_bitmap = vmx->vmcs01.msr_bitmap;
vmx_disable_intercept_for_msr(msr_bitmap, MSR_FS_BASE, MSR_TYPE_RW);
vmx_disable_intercept_for_msr(msr_bitmap, MSR_GS_BASE, MSR_TYPE_RW);
vmx_disable_intercept_for_msr(msr_bitmap, MSR_KERNEL_GS_BASE, MSR_TYPE_RW);
vmx_disable_intercept_for_msr(msr_bitmap, MSR_IA32_SYSENTER_CS, MSR_TYPE_RW);
vmx_disable_intercept_for_msr(msr_bitmap, MSR_IA32_SYSENTER_ESP, MSR_TYPE_RW);
vmx_disable_intercept_for_msr(msr_bitmap, MSR_IA32_SYSENTER_EIP, MSR_TYPE_RW);
vmx->msr_bitmap_mode = 0;
vmx->loaded_vmcs = &vmx->vmcs01;
cpu = get_cpu();
vmx_vcpu_load(&vmx->vcpu, cpu);
vmx->vcpu.cpu = cpu;
......@@ -10030,7 +10048,7 @@ static inline bool nested_vmx_prepare_msr_bitmap(struct kvm_vcpu *vcpu,
int msr;
struct page *page;
unsigned long *msr_bitmap_l1;
unsigned long *msr_bitmap_l0 = to_vmx(vcpu)->nested.msr_bitmap;
unsigned long *msr_bitmap_l0 = to_vmx(vcpu)->nested.vmcs02.msr_bitmap;
/* Nothing to do if the MSR bitmap is not in use. */
if (!cpu_has_vmx_msr_bitmap() ||
......@@ -10463,6 +10481,9 @@ static void prepare_vmcs02_full(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
vmcs_write64(GUEST_PDPTR2, vmcs12->guest_pdptr2);
vmcs_write64(GUEST_PDPTR3, vmcs12->guest_pdptr3);
}
if (cpu_has_vmx_msr_bitmap())
vmcs_write64(MSR_BITMAP, __pa(vmx->nested.vmcs02.msr_bitmap));
}
/*
......@@ -11440,7 +11461,7 @@ static void load_vmcs12_host_state(struct kvm_vcpu *vcpu,
vmcs_write64(GUEST_IA32_DEBUGCTL, 0);
if (cpu_has_vmx_msr_bitmap())
vmx_set_msr_bitmap(vcpu);
vmx_update_msr_bitmap(vcpu);
if (nested_vmx_load_msr(vcpu, vmcs12->vm_exit_msr_load_addr,
vmcs12->vm_exit_msr_load_count))
......
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