@@ -11,6 +11,7 @@ FLIC provides support to
- add interrupts (KVM_DEV_FLIC_ENQUEUE)
- inspect currently pending interrupts (KVM_FLIC_GET_ALL_IRQS)
- purge all pending floating interrupts (KVM_DEV_FLIC_CLEAR_IRQS)
+- enable/disable for the guest transparent async page faults
Groups:
KVM_DEV_FLIC_ENQUEUE
@@ -34,3 +35,12 @@ Groups:
KVM_DEV_FLIC_CLEAR_IRQS
Simply deletes all elements from the list of currently pending floating
interrupts. No interrupts are injected into the guest.
+
+ KVM_DEV_FLIC_APF_ENABLE
+ Enables async page faults for the guest. So in case of a major page fault
+ the host is allowed to handle this async and continues the guest.
+
+ KVM_DEV_FLIC_APF_DISABLE_WAIT
+ Disables async page faults for the guest and waits until already pending
+ async page faults are done. This is necessary to trigger a completion interrupt
+ for every init interrupt before migrating the interrupt list.
@@ -231,6 +231,10 @@ struct kvm_vcpu_arch {
u64 stidp_data;
};
struct gmap *gmap;
+#define KVM_S390_PFAULT_TOKEN_INVALID (-1UL)
+ unsigned long pfault_token;
+ unsigned long pfault_select;
+ unsigned long pfault_compare;
};
struct kvm_vm_stat {
@@ -257,6 +261,24 @@ static inline bool kvm_is_error_hva(unsigned long addr)
return IS_ERR_VALUE(addr);
}
+#define ASYNC_PF_PER_VCPU 64
+struct kvm_vcpu;
+struct kvm_async_pf;
+struct kvm_arch_async_pf {
+ unsigned long pfault_token;
+};
+
+bool kvm_arch_can_inject_async_page_present(struct kvm_vcpu *vcpu);
+
+void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu,
+ struct kvm_async_pf *work);
+
+void kvm_arch_async_page_not_present(struct kvm_vcpu *vcpu,
+ struct kvm_async_pf *work);
+
+void kvm_arch_async_page_present(struct kvm_vcpu *vcpu,
+ struct kvm_async_pf *work);
+
extern int sie64a(struct kvm_s390_sie_block *, u64 *);
extern char sie_exit;
#endif
@@ -20,6 +20,8 @@
#define KVM_DEV_FLIC_GET_ALL_IRQS 1
#define KVM_DEV_FLIC_ENQUEUE 2
#define KVM_DEV_FLIC_CLEAR_IRQS 3
+#define KVM_DEV_FLIC_APF_ENABLE 4
+#define KVM_DEV_FLIC_APF_DISABLE_WAIT 5
/*
* We can have up to 4*64k pending subchannels + 8 adapter interrupts,
* as well as up to ASYNC_PF_PER_VCPU*KVM_MAX_VCPUS pfault done interrupts.
@@ -23,6 +23,8 @@ config KVM
select ANON_INODES
select HAVE_KVM_CPU_RELAX_INTERCEPT
select HAVE_KVM_EVENTFD
+ select KVM_ASYNC_PF
+ select KVM_ASYNC_PF_SYNC
---help---
Support hosting paravirtualized guest machines using the SIE
virtualization capability on the mainframe. This should work
@@ -7,7 +7,7 @@
# as published by the Free Software Foundation.
KVM := ../../../virt/kvm
-common-objs = $(KVM)/kvm_main.o $(KVM)/eventfd.o
+common-objs = $(KVM)/kvm_main.o $(KVM)/eventfd.o $(KVM)/async_pf.o
ccflags-y := -Ivirt/kvm -Iarch/s390/kvm
@@ -17,6 +17,7 @@
#include "kvm-s390.h"
#include "trace.h"
#include "trace-s390.h"
+#include "gaccess.h"
static int diag_release_pages(struct kvm_vcpu *vcpu)
{
@@ -46,6 +47,87 @@ static int diag_release_pages(struct kvm_vcpu *vcpu)
return 0;
}
+static int __diag_page_ref_service(struct kvm_vcpu *vcpu)
+{
+ struct prs_parm {
+ u16 code;
+ u16 subcode;
+ u16 parm_len;
+ u16 parm_version;
+ u64 token_addr;
+ u64 select_mask;
+ u64 compare_mask;
+ u64 zarch;
+ };
+ struct prs_parm parm;
+ int rc;
+ u16 rx = (vcpu->arch.sie_block->ipa & 0xf0) >> 4;
+ u16 ry = (vcpu->arch.sie_block->ipa & 0x0f);
+ unsigned long hva_token = KVM_HVA_ERR_BAD;
+
+ if (vcpu->run->s.regs.gprs[rx] & 7)
+ return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
+ if (copy_from_guest(vcpu, &parm, vcpu->run->s.regs.gprs[rx], sizeof(parm)))
+ return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
+ if (parm.parm_version != 2 || parm.parm_len < 5 || parm.code != 0x258)
+ return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
+
+ switch (parm.subcode) {
+ case 0: /* TOKEN */
+ if (vcpu->arch.pfault_token != KVM_S390_PFAULT_TOKEN_INVALID) {
+ /*
+ * If the pagefault handshake is already activated,
+ * the token must not be changed. We have to return
+ * decimal 8 instead, as mandated in SC24-6084.
+ */
+ vcpu->run->s.regs.gprs[ry] = 8;
+ return 0;
+ }
+
+ if ((parm.compare_mask & parm.select_mask) != parm.compare_mask ||
+ parm.token_addr & 7 || parm.zarch != 0x8000000000000000ULL)
+ return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
+
+ hva_token = gfn_to_hva(vcpu->kvm, gpa_to_gfn(parm.token_addr));
+ if (kvm_is_error_hva(hva_token))
+ return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
+
+ vcpu->arch.pfault_token = parm.token_addr;
+ vcpu->arch.pfault_select = parm.select_mask;
+ vcpu->arch.pfault_compare = parm.compare_mask;
+ vcpu->run->s.regs.gprs[ry] = 0;
+ rc = 0;
+ break;
+ case 1: /*
+ * CANCEL
+ * Specification allows to let already pending tokens survive
+ * the cancel, therefore to reduce code complexity, we assume
+ * all outstanding tokens are already pending.
+ */
+ if (parm.token_addr || parm.select_mask ||
+ parm.compare_mask || parm.zarch)
+ return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
+
+ vcpu->run->s.regs.gprs[ry] = 0;
+ /*
+ * If the pfault handling was not established or is already
+ * canceled SC24-6084 requests to return decimal 4.
+ */
+ if (vcpu->arch.pfault_token == KVM_S390_PFAULT_TOKEN_INVALID)
+ vcpu->run->s.regs.gprs[ry] = 4;
+ else
+ vcpu->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID;
+
+ rc = 0;
+ break;
+ default:
+ rc = -EOPNOTSUPP;
+ break;
+ }
+
+ return rc;
+}
+
static int __diag_time_slice_end(struct kvm_vcpu *vcpu)
{
VCPU_EVENT(vcpu, 5, "%s", "diag time slice end");
@@ -150,6 +232,8 @@ int kvm_s390_handle_diag(struct kvm_vcpu *vcpu)
return __diag_time_slice_end(vcpu);
case 0x9c:
return __diag_time_slice_end_directed(vcpu);
+ case 0x258:
+ return __diag_page_ref_service(vcpu);
case 0x308:
return __diag_ipl_functions(vcpu);
case 0x500:
@@ -31,7 +31,7 @@ static int is_ioint(u64 type)
return ((type & 0xfffe0000u) != 0xfffe0000u);
}
-static int psw_extint_disabled(struct kvm_vcpu *vcpu)
+int psw_extint_disabled(struct kvm_vcpu *vcpu)
{
return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT);
}
@@ -78,11 +78,8 @@ static int __interrupt_is_deliverable(struct kvm_vcpu *vcpu,
return 1;
return 0;
case KVM_S390_INT_SERVICE:
- if (psw_extint_disabled(vcpu))
- return 0;
- if (vcpu->arch.sie_block->gcr[0] & 0x200ul)
- return 1;
- return 0;
+ case KVM_S390_INT_PFAULT_INIT:
+ case KVM_S390_INT_PFAULT_DONE:
case KVM_S390_INT_VIRTIO:
if (psw_extint_disabled(vcpu))
return 0;
@@ -150,6 +147,8 @@ static void __set_intercept_indicator(struct kvm_vcpu *vcpu,
case KVM_S390_INT_EXTERNAL_CALL:
case KVM_S390_INT_EMERGENCY:
case KVM_S390_INT_SERVICE:
+ case KVM_S390_INT_PFAULT_INIT:
+ case KVM_S390_INT_PFAULT_DONE:
case KVM_S390_INT_VIRTIO:
if (psw_extint_disabled(vcpu))
__set_cpuflag(vcpu, CPUSTAT_EXT_INT);
@@ -223,6 +222,30 @@ static void __do_deliver_interrupt(struct kvm_vcpu *vcpu,
rc |= put_guest(vcpu, inti->ext.ext_params,
(u32 __user *)__LC_EXT_PARAMS);
break;
+ case KVM_S390_INT_PFAULT_INIT:
+ trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, 0,
+ inti->ext.ext_params2);
+ rc = put_guest(vcpu, 0x2603, (u16 __user *) __LC_EXT_INT_CODE);
+ rc |= put_guest(vcpu, 0x0600, (u16 __user *) __LC_EXT_CPU_ADDR);
+ rc |= copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
+ &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
+ rc |= copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
+ __LC_EXT_NEW_PSW, sizeof(psw_t));
+ rc |= put_guest(vcpu, inti->ext.ext_params2,
+ (u64 __user *) __LC_EXT_PARAMS2);
+ break;
+ case KVM_S390_INT_PFAULT_DONE:
+ trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, 0,
+ inti->ext.ext_params2);
+ rc = put_guest(vcpu, 0x2603, (u16 __user *) __LC_EXT_INT_CODE);
+ rc |= put_guest(vcpu, 0x0680, (u16 __user *) __LC_EXT_CPU_ADDR);
+ rc |= copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
+ &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
+ rc |= copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
+ __LC_EXT_NEW_PSW, sizeof(psw_t));
+ rc |= put_guest(vcpu, inti->ext.ext_params2,
+ (u64 __user *) __LC_EXT_PARAMS2);
+ break;
case KVM_S390_INT_VIRTIO:
VCPU_EVENT(vcpu, 4, "interrupt: virtio parm:%x,parm64:%llx",
inti->ext.ext_params, inti->ext.ext_params2);
@@ -357,7 +380,7 @@ static int __try_deliver_ckc_interrupt(struct kvm_vcpu *vcpu)
return 1;
}
-static int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu)
+int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu)
{
struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
struct kvm_s390_float_interrupt *fi = vcpu->arch.local_int.float_int;
@@ -737,6 +760,10 @@ int kvm_s390_inject_vm(struct kvm *kvm,
VM_EVENT(kvm, 5, "inject: sclp parm:%x", s390int->parm);
inti->ext.ext_params = s390int->parm;
break;
+ case KVM_S390_INT_PFAULT_DONE:
+ inti->type = s390int->type;
+ inti->ext.ext_params2 = s390int->parm64;
+ break;
case KVM_S390_MCHK:
VM_EVENT(kvm, 5, "inject: machine check parm64:%llx",
s390int->parm64);
@@ -823,6 +850,10 @@ int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
inti->type = s390int->type;
inti->mchk.mcic = s390int->parm64;
break;
+ case KVM_S390_INT_PFAULT_INIT:
+ inti->type = s390int->type;
+ inti->ext.ext_params2 = s390int->parm64;
+ break;
case KVM_S390_INT_VIRTIO:
case KVM_S390_INT_SERVICE:
case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX:
@@ -877,6 +908,8 @@ static inline int copy_irq_to_user(struct kvm_s390_interrupt_info *inti,
irq.type = inti->type;
switch (inti->type) {
+ case KVM_S390_INT_PFAULT_INIT:
+ case KVM_S390_INT_PFAULT_DONE:
case KVM_S390_INT_VIRTIO:
case KVM_S390_INT_SERVICE:
irq.u.ext = inti->ext;
@@ -956,6 +989,8 @@ static inline int copy_irq_from_user(struct kvm_s390_interrupt_info *inti,
return -EFAULT;
switch (inti->type) {
+ case KVM_S390_INT_PFAULT_INIT:
+ case KVM_S390_INT_PFAULT_DONE:
case KVM_S390_INT_VIRTIO:
case KVM_S390_INT_SERVICE:
target = (void *) &inti->ext;
@@ -1019,6 +1054,8 @@ static int enqueue_floating_irq(struct kvm_device *dev,
static int flic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
{
int r = 0;
+ unsigned int i;
+ struct kvm_vcpu *vcpu;
switch (attr->group) {
case KVM_DEV_FLIC_ENQUEUE:
@@ -1028,6 +1065,20 @@ static int flic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
r = 0;
clear_floating_interrupts(dev->kvm);
break;
+ case KVM_DEV_FLIC_APF_ENABLE:
+ dev->kvm->arch.gmap->pfault_enabled = 1;
+ break;
+ case KVM_DEV_FLIC_APF_DISABLE_WAIT:
+ dev->kvm->arch.gmap->pfault_enabled = 0;
+ /*
+ * Make sure no async faults are in transition when
+ * clearing the queues. So we don't need to worry
+ * about late coming workers.
+ */
+ synchronize_srcu(&dev->kvm->srcu);
+ kvm_for_each_vcpu(i, vcpu, dev->kvm)
+ kvm_clear_async_pf_completion_queue(vcpu);
+ break;
default:
r = -EINVAL;
}
@@ -152,6 +152,7 @@ int kvm_dev_ioctl_check_extension(long ext)
#ifdef CONFIG_KVM_S390_UCONTROL
case KVM_CAP_S390_UCONTROL:
#endif
+ case KVM_CAP_ASYNC_PF:
case KVM_CAP_SYNC_REGS:
case KVM_CAP_ONE_REG:
case KVM_CAP_ENABLE_CAP:
@@ -273,6 +274,7 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
{
VCPU_EVENT(vcpu, 3, "%s", "free cpu");
trace_kvm_s390_destroy_vcpu(vcpu->vcpu_id);
+ kvm_clear_async_pf_completion_queue(vcpu);
if (!kvm_is_ucontrol(vcpu->kvm)) {
clear_bit(63 - vcpu->vcpu_id,
(unsigned long *) &vcpu->kvm->arch.sca->mcn);
@@ -322,6 +324,8 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
/* Section: vcpu related */
int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
{
+ vcpu->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID;
+ kvm_clear_async_pf_completion_queue(vcpu);
if (kvm_is_ucontrol(vcpu->kvm)) {
vcpu->arch.gmap = gmap_alloc(current->mm);
if (!vcpu->arch.gmap)
@@ -382,6 +386,8 @@ static void kvm_s390_vcpu_initial_reset(struct kvm_vcpu *vcpu)
vcpu->arch.guest_fpregs.fpc = 0;
asm volatile("lfpc %0" : : "Q" (vcpu->arch.guest_fpregs.fpc));
vcpu->arch.sie_block->gbea = 1;
+ vcpu->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID;
+ kvm_clear_async_pf_completion_queue(vcpu);
atomic_set_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags);
}
@@ -713,10 +719,89 @@ static long kvm_arch_fault_in_sync(struct kvm_vcpu *vcpu)
return rc;
}
+static void __kvm_inject_pfault_token(struct kvm_vcpu *vcpu, bool start_token,
+ unsigned long token)
+{
+ struct kvm_s390_interrupt inti;
+ inti.parm64 = token;
+
+ if (start_token) {
+ inti.type = KVM_S390_INT_PFAULT_INIT;
+ WARN_ON_ONCE(kvm_s390_inject_vcpu(vcpu, &inti));
+ } else {
+ inti.type = KVM_S390_INT_PFAULT_DONE;
+ WARN_ON_ONCE(kvm_s390_inject_vm(vcpu->kvm, &inti));
+ }
+}
+
+void kvm_arch_async_page_not_present(struct kvm_vcpu *vcpu,
+ struct kvm_async_pf *work)
+{
+ trace_kvm_s390_pfault_init(vcpu, work->arch.pfault_token);
+ __kvm_inject_pfault_token(vcpu, true, work->arch.pfault_token);
+}
+
+void kvm_arch_async_page_present(struct kvm_vcpu *vcpu,
+ struct kvm_async_pf *work)
+{
+ trace_kvm_s390_pfault_done(vcpu, work->arch.pfault_token);
+ __kvm_inject_pfault_token(vcpu, false, work->arch.pfault_token);
+}
+
+void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu,
+ struct kvm_async_pf *work)
+{
+ /* s390 will always inject the page directly */
+}
+
+bool kvm_arch_can_inject_async_page_present(struct kvm_vcpu *vcpu)
+{
+ /*
+ * s390 will always inject the page directly,
+ * but we still want check_async_completion to cleanup
+ */
+ return true;
+}
+
+static int kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu)
+{
+ hva_t hva;
+ struct kvm_arch_async_pf arch;
+ int rc;
+
+ if (vcpu->arch.pfault_token == KVM_S390_PFAULT_TOKEN_INVALID)
+ return 0;
+ if ((vcpu->arch.sie_block->gpsw.mask & vcpu->arch.pfault_select) !=
+ vcpu->arch.pfault_compare)
+ return 0;
+ if (psw_extint_disabled(vcpu))
+ return 0;
+ if (kvm_cpu_has_interrupt(vcpu))
+ return 0;
+ if (!(vcpu->arch.sie_block->gcr[0] & 0x200ul))
+ return 0;
+ if (!vcpu->arch.gmap->pfault_enabled)
+ return 0;
+
+ hva = gmap_fault(current->thread.gmap_addr, vcpu->arch.gmap);
+ if (copy_from_guest(vcpu, &arch.pfault_token, vcpu->arch.pfault_token, 8))
+ return 0;
+
+ rc = kvm_setup_async_pf(vcpu, current->thread.gmap_addr, hva, &arch);
+ return rc;
+}
+
static int vcpu_pre_run(struct kvm_vcpu *vcpu)
{
int rc, cpuflags;
+ /*
+ * On s390 notifications for arriving pages will be delivered directly
+ * to the guest but the house keeping for completed pfaults is
+ * handled outside the worker.
+ */
+ kvm_check_async_pf_completion(vcpu);
+
memcpy(&vcpu->arch.sie_block->gg14, &vcpu->run->s.regs.gprs[14], 16);
if (need_resched())
@@ -758,8 +843,10 @@ static int vcpu_post_run(struct kvm_vcpu *vcpu, int exit_reason)
rc = -EREMOTE;
} else if (current->thread.gmap_pfault) {
+ trace_kvm_s390_major_guest_pfault(vcpu);
current->thread.gmap_pfault = 0;
- if (kvm_arch_fault_in_sync(vcpu) >= 0)
+ if (kvm_arch_setup_async_pf(vcpu) ||
+ (kvm_arch_fault_in_sync(vcpu) >= 0))
rc = 0;
}
@@ -159,4 +159,8 @@ void exit_sie_sync(struct kvm_vcpu *vcpu);
/* implemented in diag.c */
int kvm_s390_handle_diag(struct kvm_vcpu *vcpu);
+/* implemented in interrupt.c */
+int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu);
+int psw_extint_disabled(struct kvm_vcpu *vcpu);
+
#endif
@@ -224,6 +224,8 @@ unlock:
static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
{
int rc;
+ unsigned int i;
+ struct kvm_vcpu *v;
switch (parameter & 0xff) {
case 0:
@@ -231,6 +233,11 @@ static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
break;
case 1:
case 2:
+ kvm_for_each_vcpu(i, v, vcpu->kvm) {
+ v->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID;
+ kvm_clear_async_pf_completion_queue(v);
+ }
+
rc = SIGP_CC_ORDER_CODE_ACCEPTED;
break;
default:
@@ -30,6 +30,52 @@
TP_printk("%02d[%016lx-%016lx]: " p_str, __entry->id, \
__entry->pswmask, __entry->pswaddr, p_args)
+TRACE_EVENT(kvm_s390_major_guest_pfault,
+ TP_PROTO(VCPU_PROTO_COMMON),
+ TP_ARGS(VCPU_ARGS_COMMON),
+
+ TP_STRUCT__entry(
+ VCPU_FIELD_COMMON
+ ),
+
+ TP_fast_assign(
+ VCPU_ASSIGN_COMMON
+ ),
+ VCPU_TP_PRINTK("%s", "major fault, maybe applicable for pfault")
+ );
+
+TRACE_EVENT(kvm_s390_pfault_init,
+ TP_PROTO(VCPU_PROTO_COMMON, long pfault_token),
+ TP_ARGS(VCPU_ARGS_COMMON, pfault_token),
+
+ TP_STRUCT__entry(
+ VCPU_FIELD_COMMON
+ __field(long, pfault_token)
+ ),
+
+ TP_fast_assign(
+ VCPU_ASSIGN_COMMON
+ __entry->pfault_token = pfault_token;
+ ),
+ VCPU_TP_PRINTK("init pfault token %ld", __entry->pfault_token)
+ );
+
+TRACE_EVENT(kvm_s390_pfault_done,
+ TP_PROTO(VCPU_PROTO_COMMON, long pfault_token),
+ TP_ARGS(VCPU_ARGS_COMMON, pfault_token),
+
+ TP_STRUCT__entry(
+ VCPU_FIELD_COMMON
+ __field(long, pfault_token)
+ ),
+
+ TP_fast_assign(
+ VCPU_ASSIGN_COMMON
+ __entry->pfault_token = pfault_token;
+ ),
+ VCPU_TP_PRINTK("done pfault token %ld", __entry->pfault_token)
+ );
+
/*
* Tracepoints for SIE entry and exit.
*/
@@ -413,6 +413,8 @@ struct kvm_s390_psw {
#define KVM_S390_PROGRAM_INT 0xfffe0001u
#define KVM_S390_SIGP_SET_PREFIX 0xfffe0002u
#define KVM_S390_RESTART 0xfffe0003u
+#define KVM_S390_INT_PFAULT_INIT 0xfffe0004u
+#define KVM_S390_INT_PFAULT_DONE 0xfffe0005u
#define KVM_S390_MCHK 0xfffe1000u
#define KVM_S390_INT_VIRTIO 0xffff2603u
#define KVM_S390_INT_SERVICE 0xffff2401u