diff --git a/arch/x86/kernel/cpu.c b/arch/x86/kernel/cpu.c
index d7f2ec55..886964b1 100644
--- a/arch/x86/kernel/cpu.c
+++ b/arch/x86/kernel/cpu.c
@@ -405,7 +405,7 @@ void setup_x86_ap(void (*next_func)(void))
 }
 
 void arch_show_interrupt_context(const void *reg);
-void set_signal(int sig, void *regs);
+void set_signal(int sig, void *regs, struct siginfo *info);
 void check_signal(unsigned long rc, void *regs);
 extern void tlb_flush_handler(int vector);
 
@@ -452,10 +452,13 @@ void handle_interrupt(int vector, struct x86_regs *regs)
 
 void gpe_handler(struct x86_regs *regs)
 {
+	struct siginfo info;
+
 	kprintf("General protection fault (err: %lx, %lx:%lx)\n",
 	        regs->error, regs->cs, regs->rip);
 	arch_show_interrupt_context(regs);
-	set_signal(SIGILL, regs);
+	memset(&info, '\0', sizeof info);
+	set_signal(SIGILL, regs, &info);
 	check_signal(0, regs);
 	check_need_resched();
 	// panic("GPF");
diff --git a/arch/x86/kernel/include/signal.h b/arch/x86/kernel/include/signal.h
index 33820ce9..2d1a8717 100644
--- a/arch/x86/kernel/include/signal.h
+++ b/arch/x86/kernel/include/signal.h
@@ -36,13 +36,13 @@ struct sigaction {
 	sigset_t sa_mask;
 };
 
-#define SA_NOCLDSTOP    0x00000001u
-#define SA_NOCLDWAIT    0x00000002u
-#define SA_NODEFER      0x40000000u
-#define SA_ONSTACK      0x08000000u
-#define SA_RESETHAND    0x80000000u
-#define SA_RESTART      0x10000000u
-#define SA_SIGINFO      0x00000004u
+#define SA_NOCLDSTOP    0x00000001U
+#define SA_NOCLDWAIT    0x00000002U
+#define SA_NODEFER      0x40000000U
+#define SA_ONSTACK      0x08000000U
+#define SA_RESETHAND    0x80000000U
+#define SA_RESTART      0x10000000U
+#define SA_SIGINFO      0x00000004U
 
 struct k_sigaction {
         struct sigaction sa;
@@ -71,6 +71,16 @@ typedef struct siginfo {
 	int si_errno;		/* If non-zero, an errno value associated with
 				   this signal, as defined in <errno.h>.  */
 	int si_code;		/* Signal code.  */
+#define SI_USER         0       /* sent by kill, sigsend, raise */
+#define SI_KERNEL       0x80    /* sent by the kernel from somewhere */
+#define SI_QUEUE        -1      /* sent by sigqueue */
+#define SI_TIMER __SI_CODE(__SI_TIMER,-2) /* sent by timer expiration */
+#define SI_MESGQ __SI_CODE(__SI_MESGQ,-3) /* sent by real time mesq state change
+ */
+#define SI_ASYNCIO      -4      /* sent by AIO completion */
+#define SI_SIGIO        -5      /* sent by queued SIGIO */
+#define SI_TKILL        -6      /* sent by tkill system call */
+#define SI_DETHREAD     -7      /* sent by execve() killing subsidiary threads */
 
 	union {
 		int _pad[__SI_PAD_SIZE];
@@ -117,6 +127,29 @@ typedef struct siginfo {
 	} _sifields;
 } siginfo_t;
 
+struct signalfd_siginfo {
+	unsigned int ssi_signo;
+	int ssi_errno;
+	int ssi_code;
+	unsigned int ssi_pid;
+	unsigned int ssi_uid;
+	int ssi_fd;
+	unsigned int ssi_tid;
+	unsigned int ssi_band;
+	unsigned int ssi_overrun;
+	unsigned int ssi_trapno;
+	int ssi_status;
+	int ssi_int;
+	unsigned long ssi_ptr;
+	unsigned long ssi_utime;
+	unsigned long ssi_stime;
+	unsigned long ssi_addr;
+	unsigned short ssi_addr_lsb;
+
+	char __pad[46];
+};
+
+
 #define SIGHUP           1
 #define SIGINT           2
 #define SIGQUIT          3
diff --git a/arch/x86/kernel/include/syscall_list.h b/arch/x86/kernel/include/syscall_list.h
index adc3a94e..7f95a451 100644
--- a/arch/x86/kernel/include/syscall_list.h
+++ b/arch/x86/kernel/include/syscall_list.h
@@ -84,6 +84,8 @@ SYSCALL_HANDLED(218, set_tid_address)
 SYSCALL_HANDLED(231, exit_group)
 SYSCALL_HANDLED(234, tgkill)
 SYSCALL_HANDLED(273, set_robust_list)
+SYSCALL_HANDLED(282, signalfd)
+SYSCALL_HANDLED(289, signalfd4)
 #ifdef DCFA_KMOD
 SYSCALL_HANDLED(303, mod_call)
 #endif
diff --git a/arch/x86/kernel/syscall.c b/arch/x86/kernel/syscall.c
index bdb5822a..aa82716e 100644
--- a/arch/x86/kernel/syscall.c
+++ b/arch/x86/kernel/syscall.c
@@ -135,6 +135,7 @@ struct sigsp {
 	unsigned long sigrc;
 	unsigned long sigmask;
 	int ssflags;
+	siginfo_t info;
 };
 
 SYSCALL_DECLARE(rt_sigreturn)
@@ -157,7 +158,7 @@ SYSCALL_DECLARE(rt_sigreturn)
 }
 
 extern struct cpu_local_var *clv;
-extern unsigned long do_kill(int pid, int tid, int sig);
+extern unsigned long do_kill(int pid, int tid, int sig, struct siginfo *info);
 extern void interrupt_syscall(int all, int pid);
 extern int num_processors;
 
@@ -253,12 +254,17 @@ do_signal(unsigned long rc, void *regs0, struct process *proc, struct sig_pendin
 		}
 		sigsp->sigmask = mask;
 		sigsp->ssflags = ssflags;
+		memcpy(&sigsp->info, &pending->info, sizeof(siginfo_t));
 
 		usp = (unsigned long *)sigsp;
 		usp--;
 		*usp = (unsigned long)k->sa.sa_restorer;
 
 		regs->rdi = (unsigned long)sig;
+		if(k->sa.sa_flags & SA_SIGINFO){
+			regs->rsi = (unsigned long)&sigsp->info;
+			regs->rdx = 0;
+		}
 		regs->rip = (unsigned long)k->sa.sa_handler;
 		regs->rsp = (unsigned long)usp;
 
@@ -374,7 +380,7 @@ check_signal(unsigned long rc, void *regs0)
 }
 
 unsigned long
-do_kill(int pid, int tid, int sig)
+do_kill(int pid, int tid, int sig, siginfo_t *info)
 {
 	struct cpu_local_var *v;
 	struct process *p;
@@ -435,9 +441,9 @@ do_kill(int pid, int tid, int sig)
 			ihk_mc_spinlock_unlock(&(v->runq_lock), irqstate);
 		}
 		for(i = 0; i < n; i++)
-			rc = do_kill(pids[i], -1, sig);
+			rc = do_kill(pids[i], -1, sig, info);
 		if(sendme)
-			rc = do_kill(proc->pid, -1, sig);
+			rc = do_kill(proc->pid, -1, sig, info);
 
 		kfree(pids);
 		return rc;
@@ -563,11 +569,12 @@ do_kill(int pid, int tid, int sig)
 		if(pending == NULL){
 			doint = 1;
 			pending = kmalloc(sizeof(struct sig_pending), IHK_MC_AP_NOWAIT);
-			pending->sigmask.__val[0] = mask;
 			if(!pending){
 				rc = -ENOMEM;
 			}
 			else{
+				pending->sigmask.__val[0] = mask;
+				memcpy(&pending->info, info, sizeof(siginfo_t));
 				list_add_tail(&pending->list, head);
 				tproc->sigevent = 1;
 			}
@@ -625,7 +632,7 @@ do_kill(int pid, int tid, int sig)
 }
 
 void
-set_signal(int sig, void *regs0)
+set_signal(int sig, void *regs0, siginfo_t *info)
 {
 	struct x86_regs *regs = regs0;
 	struct process *proc = cpu_local_var(current);
@@ -639,5 +646,5 @@ set_signal(int sig, void *regs0)
 		terminate(0, sig | 0x80, (ihk_mc_user_context_t *)regs->rsp);
 	}
 	else
-		do_kill(proc->pid, proc->tid, sig);
+		do_kill(proc->pid, proc->tid, sig, info);
 }
diff --git a/executer/include/uprotocol.h b/executer/include/uprotocol.h
index 8a9b998b..5c630362 100644
--- a/executer/include/uprotocol.h
+++ b/executer/include/uprotocol.h
@@ -153,6 +153,7 @@ struct signal_desc {
 	int pid;
 	int tid;
 	int sig;
+	char info[128];
 };
 
 #endif
diff --git a/executer/kernel/control.c b/executer/kernel/control.c
index 9e8ed75e..5857aeb7 100644
--- a/executer/kernel/control.c
+++ b/executer/kernel/control.c
@@ -270,27 +270,57 @@ static long mcexec_start_image(ihk_os_t os,
 	return 0;
 }
 
+static DECLARE_WAIT_QUEUE_HEAD(signalq);
+
 static long mcexec_send_signal(ihk_os_t os, struct signal_desc *sigparam)
 {
 	struct ikc_scd_packet isp;
 	struct mcctrl_channel *c;
 	struct mcctrl_usrdata *usrdata = ihk_host_os_get_usrdata(os);
 	struct signal_desc sig;
+	struct mcctrl_signal msig[2];
+	struct mcctrl_signal *msigp;
+	int rc;
 
 	if (copy_from_user(&sig, sigparam, sizeof(struct signal_desc))) {
 		return -EFAULT;
 	}
+
+	msigp = msig;
+	if(((unsigned long)msig & 0xfffffffffffff000L) !=
+	   ((unsigned long)(msig + 1) & 0xfffffffffffff000L))
+		msigp++;
+	memset(msigp, '\0', sizeof msig);
+	msigp->sig = sig.sig;
+	msigp->pid = sig.pid;
+	msigp->tid = sig.tid;
+	memcpy(&msigp->info, &sig.info, 128);
+
 	c = usrdata->channels;
 	isp.msg = SCD_MSG_SEND_SIGNAL;
 	isp.ref = sig.cpu;
 	isp.pid = sig.pid;
-	isp.arg = (long)sig.tid << 32 | (sig.sig & 0x00000000ffffffffL);
+	isp.arg = virt_to_phys(msigp);
 
-	mcctrl_ikc_send(os, sig.cpu, &isp);
+	if((rc = mcctrl_ikc_send(os, sig.cpu, &isp)) < 0){
+		printk("mcexec_send_signal: mcctrl_ikc_send ret=%d\n", rc);
+		return rc;
+	}
+	wait_event_interruptible(signalq, msigp->cond != 0);
 
 	return 0;
 }
 
+void
+sig_done(unsigned long arg, int err)
+{
+	struct mcctrl_signal *msigp;
+
+	msigp = phys_to_virt(arg);
+	msigp->cond = 1;
+	wake_up_interruptible(&signalq);
+}
+
 static long mcexec_get_cpu(ihk_os_t os)
 {
 	struct ihk_cpu_info *info;
diff --git a/executer/kernel/ikc.c b/executer/kernel/ikc.c
index 5612c77c..92aee2fd 100644
--- a/executer/kernel/ikc.c
+++ b/executer/kernel/ikc.c
@@ -44,6 +44,7 @@ int mcexec_syscall(struct mcctrl_channel *c, int pid, unsigned long arg);
 void procfs_create(void *__os, int ref, int osnum, int pid, unsigned long arg);
 void procfs_delete(void *__os, int osnum, unsigned long arg);
 void procfs_answer(unsigned long arg, int err);
+void sig_done(unsigned long arg, int err);
 
 static int syscall_packet_handler(struct ihk_ikc_channel_desc *c,
                                   void *__packet, void *__os)
@@ -79,8 +80,11 @@ static int syscall_packet_handler(struct ihk_ikc_channel_desc *c,
 	case SCD_MSG_PROCFS_ANSWER:
 		procfs_answer(pisp->arg, pisp->err);
 		break;
-	}
 
+	case SCD_MSG_SEND_SIGNAL:
+		sig_done(pisp->arg, pisp->err);
+		break;
+	}
 	return 0;
 }
 
diff --git a/executer/kernel/mcctrl.h b/executer/kernel/mcctrl.h
index 1abe4550..d4b0e810 100644
--- a/executer/kernel/mcctrl.h
+++ b/executer/kernel/mcctrl.h
@@ -145,6 +145,14 @@ struct mcctrl_usrdata {
 	void **keys;
 };
 
+struct mcctrl_signal {
+	int	cond;
+	int	sig;
+	int	pid;
+	int	tid;
+	char	info[128];
+};
+
 int mcctrl_ikc_send(ihk_os_t os, int cpu, struct ikc_scd_packet *pisp);
 int mcctrl_ikc_send_msg(ihk_os_t os, int cpu, int msg, int ref, unsigned long arg);
 int mcctrl_ikc_is_valid_thread(ihk_os_t os, int cpu);
diff --git a/executer/user/mcexec.c b/executer/user/mcexec.c
index 1822674a..f3cc9a8b 100644
--- a/executer/user/mcexec.c
+++ b/executer/user/mcexec.c
@@ -820,6 +820,7 @@ sendsig(int sig, siginfo_t *siginfo, void *context)
 	sigdesc.pid = (int)pid;
 	sigdesc.tid = remote_tid;
 	sigdesc.sig = sig;
+	memcpy(&sigdesc.info, siginfo, 128);
 	if (ioctl(fd, MCEXEC_UP_SEND_SIGNAL, &sigdesc) != 0) {
 		perror("send_signal");
 		close(fd);
diff --git a/kernel/host.c b/kernel/host.c
index c5bb31ab..7061d055 100644
--- a/kernel/host.c
+++ b/kernel/host.c
@@ -496,7 +496,7 @@ static void syscall_channel_send(struct ihk_ikc_channel_desc *c,
 	ihk_ikc_send(c, packet, 0);
 }
 
-extern unsigned long do_kill(int, int, int);
+extern unsigned long do_kill(int, int, int, struct siginfo *);
 extern void settid(struct process *proc, int mode, int newcpuid, int oldcpuid);
 
 extern void process_procfs_request(unsigned long rarg);
@@ -508,6 +508,14 @@ static int syscall_packet_handler(struct ihk_ikc_channel_desc *c,
 	struct ikc_scd_packet pckt;
 	int rc;
 	struct process *proc;
+	struct mcctrl_signal {
+		int	cond;
+		int	sig;
+		int	pid;
+		int	tid;
+		struct siginfo	info;
+	} *sp, info;
+	unsigned long pp;
 
 	switch (packet->msg) {
 	case SCD_MSG_INIT_CHANNEL_ACKED:
@@ -540,8 +548,19 @@ static int syscall_packet_handler(struct ihk_ikc_channel_desc *c,
 		//cpu_local_var(next) = (struct process *)packet->arg;
 		return 0;
 	case SCD_MSG_SEND_SIGNAL:
-		rc = do_kill((int)packet->pid, (int)(packet->arg >> 32), packet->arg & 0x00000000ffffffffL);
-		kprintf("SCD_MSG_SEND_SIGNAL: %lx, rc=%d\n", packet->arg, rc);
+		pp = ihk_mc_map_memory(NULL, packet->arg, sizeof(struct mcctrl_signal));
+		sp = (struct mcctrl_signal *)ihk_mc_map_virtual(pp, 1, PTATTR_WRITABLE | PTATTR_ACTIVE);
+		memcpy(&info, sp, sizeof(struct mcctrl_signal));
+		ihk_mc_unmap_virtual(sp, 1, 0);
+		ihk_mc_unmap_memory(NULL, pp, sizeof(struct mcctrl_signal));
+		pckt.msg = SCD_MSG_SEND_SIGNAL;
+		pckt.err = 0;
+		pckt.ref = packet->ref;
+		pckt.arg = packet->arg;
+		syscall_channel_send(c, &pckt);
+
+		rc = do_kill(info.pid, info.tid, info.sig, &info.info);
+		kprintf("SCD_MSG_SEND_SIGNAL: do_kill(pid=%d, tid=%d, sig=%d)=%d\n", info.pid, info.tid, info.sig, rc);
 		return 0;
 	case SCD_MSG_PROCFS_REQUEST:
 		process_procfs_request(packet->arg);
diff --git a/kernel/mem.c b/kernel/mem.c
index 0ad1d0bc..5aea9dac 100644
--- a/kernel/mem.c
+++ b/kernel/mem.c
@@ -168,7 +168,7 @@ static struct ihk_mc_interrupt_handler query_free_mem_handler = {
 	.priv = NULL,
 };
 
-void set_signal(int sig, void *regs);
+void set_signal(int sig, void *regs, struct siginfo *info);
 void check_signal(unsigned long rc, void *regs);
 int gencore(struct process *, void *, struct coretable **, int *);
 void freecore(struct coretable **);
@@ -371,16 +371,19 @@ static void page_fault_handler(void *fault_addr, uint64_t reason, void *regs)
 
 	error = page_fault_process(proc, fault_addr, reason);
 	if (error) {
+		struct siginfo info;
+
 		kprintf("[%d]page_fault_handler(%p,%lx,%p):"
 				"fault proc failed. %d\n",
 				ihk_mc_get_processor_id(), fault_addr,
 				reason, regs, error);
 		unhandled_page_fault(proc, fault_addr, regs);
+		memset(&info, '\0', sizeof info);
 		if (error == -ERANGE) {
-			set_signal(SIGBUS, regs);
+			set_signal(SIGBUS, regs, &info);
 		}
 		else {
-			set_signal(SIGSEGV, regs);
+			set_signal(SIGSEGV, regs, &info);
 		}
 		check_signal(0, regs);
 		goto out;
diff --git a/kernel/syscall.c b/kernel/syscall.c
index 87d7132e..74d3aafa 100644
--- a/kernel/syscall.c
+++ b/kernel/syscall.c
@@ -95,7 +95,7 @@ static char *syscall_name[] MCKERNEL_UNUSED = {
 
 void check_signal(unsigned long rc, void *regs);
 void do_signal(long rc, void *regs, struct process *proc, struct sig_pending *pending);
-extern unsigned long do_kill(int pid, int tid, int sig);
+extern unsigned long do_kill(int pid, int tid, int sig, struct siginfo *info);
 int copy_from_user(struct process *, void *, const void *, size_t);
 int copy_to_user(struct process *, void *, const void *, size_t);
 void do_setpgid(int, int);
@@ -460,7 +460,13 @@ terminate(int rc, int sig, ihk_mc_user_context_t *ctx)
 		/* Signal parent if still attached */
 		ihk_mc_spinlock_lock_noirq(&ftn->parent->lock);
 		if (ftn->parent->owner) {
-			do_kill(ftn->parent->owner->pid, -1, SIGCHLD);
+			struct siginfo info;
+			memset(&info, '\0', sizeof info);
+			info.si_signo = SIGCHLD;
+			info.si_code = sig? ((sig & 0x80)? 3: 2): 1;
+			info._sifields._sigchld.si_pid = proc->pid;
+			info._sifields._sigchld.si_status = ((rc & 0x00ff) << 8) | (sig & 0xff);
+			do_kill(ftn->parent->owner->pid, -1, SIGCHLD, &info);
 /*
 			sigchld_parent(ftn->parent->owner, 0);
 */
@@ -1513,8 +1519,15 @@ SYSCALL_DECLARE(kill)
 {
 	int pid = ihk_mc_syscall_arg0(ctx);
 	int sig = ihk_mc_syscall_arg1(ctx);
+	struct process *proc = cpu_local_var(current);
+	struct siginfo info;
 
-	return do_kill(pid, -1, sig);
+	memset(&info, '\0', sizeof info);
+	info.si_signo = sig;
+	info.si_code = SI_USER;
+	info._sifields._kill.si_pid = proc->pid;
+
+	return do_kill(pid, -1, sig, &info);
 }
 
 // see linux-2.6.34.13/kernel/signal.c
@@ -1523,13 +1536,20 @@ SYSCALL_DECLARE(tgkill)
 	int tgid = ihk_mc_syscall_arg0(ctx);
 	int tid = ihk_mc_syscall_arg1(ctx);
 	int sig = ihk_mc_syscall_arg2(ctx);
+	struct process *proc = cpu_local_var(current);
+	struct siginfo info;
+
+	memset(&info, '\0', sizeof info);
+	info.si_signo = sig;
+	info.si_code = SI_TKILL;
+	info._sifields._kill.si_pid = proc->pid;
 
 	if(tid <= 0)
 		return -EINVAL;
 	if(tgid <= 0 && tgid != -1)
 		return -EINVAL;
 
-	return do_kill(tgid, tid, sig);
+	return do_kill(tgid, tid, sig, &info);
 }
 
 SYSCALL_DECLARE(setpgid)
@@ -1650,6 +1670,16 @@ SYSCALL_DECLARE(rt_sigpending)
 	return 0;
 }
 
+SYSCALL_DECLARE(signalfd)
+{
+	return -EOPNOTSUPP;
+}
+
+SYSCALL_DECLARE(signalfd4)
+{
+	return -EOPNOTSUPP;
+}
+
 SYSCALL_DECLARE(rt_sigtimedwait)
 {
 	struct process *proc = cpu_local_var(current);
@@ -1664,29 +1694,38 @@ SYSCALL_DECLARE(rt_sigtimedwait)
 	if (sigsetsize > sizeof(sigset_t))
 		return -EINVAL;
 
+	if(set == NULL)
+		return -EFAULT;
 	memset(&winfo, '\0', sizeof winfo);
 	if(copy_from_user(proc, &wset, set, sizeof wset))
 		return -EFAULT;
-	if(copy_from_user(proc, wtimeout, timeout, sizeof wtimeout))
-		return -EFAULT;
-	if(copy_to_user(proc, info, &winfo, sizeof winfo))
-		return -EFAULT;
+	if(timeout)
+		if(copy_from_user(proc, wtimeout, timeout, sizeof wtimeout))
+			return -EFAULT;
+
+
+	if(info)
+		if(copy_to_user(proc, info, &winfo, sizeof winfo))
+			return -EFAULT;
 
 	return -EOPNOTSUPP;
 }
 
 SYSCALL_DECLARE(rt_sigqueueinfo)
 {
-	struct process *proc = cpu_local_var(current);
 	int pid = (int)ihk_mc_syscall_arg0(ctx);
 	int sig = (int)ihk_mc_syscall_arg1(ctx);
-	siginfo_t *info = (siginfo_t *)ihk_mc_syscall_arg2(ctx);
-	siginfo_t winfo;
+	void *winfo = (void *)ihk_mc_syscall_arg2(ctx);
+	struct process *proc = cpu_local_var(current);
+	struct siginfo info;
 
-	if(copy_from_user(proc, &winfo, info, sizeof winfo))
+	if(pid <= 0)
+		return -ESRCH;
+
+	if(copy_from_user(proc, &info, winfo, sizeof info))
 		return -EFAULT;
 
-	return -EOPNOTSUPP;
+	return do_kill(pid, -1, sig, &info);
 }
 
 static int