diff --git a/usr.bin/kdump/kdump.c b/usr.bin/kdump/kdump.c
--- a/usr.bin/kdump/kdump.c
+++ b/usr.bin/kdump/kdump.c
@@ -1529,6 +1529,14 @@
 				narg--;
 				c = ',';
 				break;
+			case SYS_getitimer:
+			case SYS_setitimer:
+				putchar('(');
+				print_integer_arg(sysdecode_itimer, *ip);
+				ip++;
+				narg--;
+				c = ',';
+				break;
 			}
 			switch (ktr->ktr_code) {
 			case SYS_chflagsat:
diff --git a/usr.bin/kdump/linux.c b/usr.bin/kdump/linux.c
--- a/usr.bin/kdump/linux.c
+++ b/usr.bin/kdump/linux.c
@@ -117,6 +117,14 @@
 		print_number(ip, narg, c);
 		print_number64(first, ip, narg, c);
 		break;
+	case LINUX_SYS_linux_getitimer:
+	case LINUX_SYS_linux_setitimer:
+		putchar('(');
+		print_integer_arg(sysdecode_itimer, *ip);
+		ip++;
+		narg--;
+		c = ',';
+		break;
 	}
 	*resc = c;
 	*resip = ip;
@@ -183,6 +191,14 @@
 		print_number(ip, narg, c);
 		print_number64(first, ip, narg, c);
 		break;
+	case LINUX32_SYS_linux_getitimer:
+	case LINUX32_SYS_linux_setitimer:
+		putchar('(');
+		print_integer_arg(sysdecode_itimer, *ip);
+		ip++;
+		narg--;
+		c = ',';
+		break;
 	}
 	*resc = c;
 	*resip = ip;
diff --git a/usr.bin/truss/syscall.h b/usr.bin/truss/syscall.h
--- a/usr.bin/truss/syscall.h
+++ b/usr.bin/truss/syscall.h
@@ -101,6 +101,7 @@
 	Getfsstatmode,
 	Idtype,
 	Ioctl,
+	Itimerwhich,
 	Kldsymcmd,
 	Kldunloadflags,
 	LioMode,
diff --git a/usr.bin/truss/syscalls.c b/usr.bin/truss/syscalls.c
--- a/usr.bin/truss/syscalls.c
+++ b/usr.bin/truss/syscalls.c
@@ -296,7 +296,7 @@
 	{ .name = "getfsstat", .ret_type = 1, .nargs = 3,
 	  .args = { { Ptr, 0 }, { Long, 1 }, { Getfsstatmode, 2 } } },
 	{ .name = "getitimer", .ret_type = 1, .nargs = 2,
-	  .args = { { Int, 0 }, { Itimerval | OUT, 2 } } },
+	  .args = { { Itimerwhich, 0 }, { Itimerval | OUT, 2 } } },
 	{ .name = "getpeername", .ret_type = 1, .nargs = 3,
 	  .args = { { Int, 0 }, { Sockaddr | OUT, 1 }, { Ptr | OUT, 2 } } },
 	{ .name = "getpgid", .ret_type = 1, .nargs = 1,
@@ -506,7 +506,8 @@
 	            { Msgflags, 3 }, { Sockaddr | IN, 4 },
 	            { Socklent | IN, 5 } } },
 	{ .name = "setitimer", .ret_type = 1, .nargs = 3,
-	  .args = { { Int, 0 }, { Itimerval, 1 }, { Itimerval | OUT, 2 } } },
+	  .args = { { Itimerwhich, 0 }, { Itimerval, 1 },
+		    { Itimerval | OUT, 2 } } },
 	{ .name = "setpriority", .ret_type = 1, .nargs = 3,
 	  .args = { { Priowhich, 0 }, { Int, 1 }, { Int, 2 } } },
 	{ .name = "setrlimit", .ret_type = 1, .nargs = 2,
@@ -607,6 +608,8 @@
 	{ .name = "linux_execve", .ret_type = 1, .nargs = 3,
 	  .args = { { Name | IN, 0 }, { ExecArgs | IN, 1 },
 		    { ExecEnv | IN, 2 } } },
+	{ .name = "linux_getitimer", .ret_type = 1, .nargs = 2,
+	  .args = { { Itimerwhich, 0 }, { Itimerval | OUT, 2 } } },
 	{ .name = "linux_lseek", .ret_type = 2, .nargs = 3,
 	  .args = { { Int, 0 }, { Int, 1 }, { Whence, 2 } } },
 	{ .name = "linux_mkdir", .ret_type = 1, .nargs = 2,
@@ -619,6 +622,9 @@
 	  .args = { { Name, 0 }, { Hex, 1 }, { Octal, 2 } } },
 	{ .name = "linux_readlink", .ret_type = 1, .nargs = 3,
 	  .args = { { Name, 0 }, { Name | OUT, 1 }, { Sizet, 2 } } },
+	{ .name = "linux_setitimer", .ret_type = 1, .nargs = 3,
+	  .args = { { Itimerwhich, 0 }, { Itimerval, 1 },
+		    { Itimerval | OUT, 2 } } },
 	{ .name = "linux_socketcall", .ret_type = 1, .nargs = 2,
 	  .args = { { Int, 0 }, { LinuxSockArgs, 1 } } },
 	{ .name = "linux_stat64", .ret_type = 1, .nargs = 2,
@@ -2445,6 +2451,9 @@
 		print_integer_arg(sysdecode_getfsstat_mode, fp,
 		    args[sc->offset]);
 		break;
+	case Itimerwhich:
+		print_integer_arg(sysdecode_itimer, fp, args[sc->offset]);
+		break;
 	case Kldsymcmd:
 		print_integer_arg(sysdecode_kldsym_cmd, fp, args[sc->offset]);
 		break;