--- libgo/configure.ac	(revision 249471)
+++ libgo/configure.ac	(revision 249472)
@@ -580,7 +580,7 @@ AC_C_BIGENDIAN
 
 GCC_CHECK_UNWIND_GETIPINFO
 
-AC_CHECK_HEADERS(port.h sched.h semaphore.h sys/file.h sys/mman.h syscall.h sys/epoll.h sys/event.h sys/inotify.h sys/ptrace.h sys/syscall.h sys/user.h sys/utsname.h sys/select.h sys/socket.h net/if.h net/if_arp.h net/route.h netpacket/packet.h sys/prctl.h sys/mount.h sys/vfs.h sys/statfs.h sys/timex.h sys/sysinfo.h utime.h linux/ether.h linux/fs.h linux/reboot.h netinet/icmp6.h netinet/in_syst.h netinet/ip.h netinet/ip_mroute.h netinet/if_ether.h)
+AC_CHECK_HEADERS(port.h sched.h semaphore.h sys/file.h sys/mman.h syscall.h sys/epoll.h sys/event.h sys/inotify.h sys/ptrace.h sys/syscall.h sys/user.h sys/utsname.h sys/select.h sys/socket.h net/if.h net/if_arp.h net/route.h netpacket/packet.h sys/prctl.h sys/mount.h sys/vfs.h sys/statfs.h sys/timex.h sys/sysinfo.h utime.h linux/ether.h linux/fs.h linux/ptrace.h linux/reboot.h netinet/icmp6.h netinet/in_syst.h netinet/ip.h netinet/ip_mroute.h netinet/if_ether.h)
 
 AC_CHECK_HEADERS([linux/filter.h linux/if_addr.h linux/if_ether.h linux/if_tun.h linux/netlink.h linux/rtnetlink.h], [], [],
 [#ifdef HAVE_SYS_SOCKET_H
--- libgo/sysinfo.c	(revision 249471)
+++ libgo/sysinfo.c	(revision 250324)
@@ -102,6 +102,18 @@
 #if defined(HAVE_LINUX_NETLINK_H)
 #include <linux/netlink.h>
 #endif
+#if defined(HAVE_LINUX_PTRACE_H)
+/* Avoid https://sourceware.org/bugzilla/show_bug.cgi?id=762 .  */
+#define ia64_fpreg pt_ia64_fpreg
+#define pt_all_user_regs pt_ia64_all_user_regs
+/* Avoid redefinition of ptrace_peeksiginfo from <sys/ptrace.h>.
+   https://gcc.gnu.org/PR81324 .  */
+#define ptrace_peeksiginfo_args ignore_ptrace_peeksiginfo_args
+#include <linux/ptrace.h>
+#undef ia64_fpreg
+#undef pt_all_user_regs
+#undef ptrace_peeksiginfo_args
+#endif
 #if defined(HAVE_LINUX_RTNETLINK_H)
 #include <linux/rtnetlink.h>
 #endif
--- libgo/mksysinfo.sh	(revision 249711)
+++ libgo/mksysinfo.sh	(revision 249712)
@@ -294,16 +294,6 @@ upcase_fields () {
 # GNU/Linux specific; it should do no harm if there is no
 # _user_regs_struct.
 regs=`grep '^type _user_regs_struct struct' gen-sysinfo.go || true`
-if test "$regs" = ""; then
-  # s390
-  regs=`grep '^type __user_regs_struct struct' gen-sysinfo.go || true`
-  if test "$regs" != ""; then
-    # Substructures of __user_regs_struct on s390
-    upcase_fields "__user_psw_struct" "PtracePsw" >> ${OUT} || true
-    upcase_fields "__user_fpregs_struct" "PtraceFpregs" >> ${OUT} || true
-    upcase_fields "__user_per_struct" "PtracePer" >> ${OUT} || true
-  fi
-fi
 if test "$regs" != ""; then
   regs=`echo $regs |
     sed -e 's/type __*user_regs_struct struct //' -e 's/[{}]//g'`
--- libgo/go/syscall/syscall_linux_s390x.go	(revision 250173)
+++ libgo/go/syscall/syscall_linux_s390x.go	(revision 250174)
@@ -4,18 +4,45 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// The PtraceRegs struct generated for go looks like this:
+//
+// type PtraceRegs struct
+// {
+//   Psw _psw_t;
+//   Gprs [15+1]uint64;
+//   Acrs [15+1]uint32;
+//   Orig_gpr2 uint64;
+//   Fp_regs _s390_fp_regs;
+//   Per_info _per_struct;
+//   Ieee_instruction_pointer uint64;
+// }
+//
+// The GETREGSET/SETREGSET ptrace commands on S/390 only read/write
+// the content up to Orig_gpr2.  Hence, we use
+// PEEKUSR_AREA/POKEUSR_AREA like GDB does.
+
 package syscall
 
 import "unsafe"
 
-func (r *PtraceRegs) PC() uint64 { return r.Psw.Addr }
+func (r *PtraceRegs) PC() uint64 { return r.Psw.addr }
 
-func (r *PtraceRegs) SetPC(pc uint64) { r.Psw.Addr = pc }
+func (r *PtraceRegs) SetPC(pc uint64) { r.Psw.addr = pc }
 
-func PtraceGetRegs(pid int, regsout *PtraceRegs) (err error) {
-	return ptrace(PTRACE_GETREGS, pid, 0, uintptr(unsafe.Pointer(regsout)))
+func PtraceGetRegs(pid int, regs *PtraceRegs) (err error) {
+	parea := _ptrace_area{
+		_sizeof_ptrace_area,
+		0,
+		uint64(uintptr(unsafe.Pointer(regs))),
+	}
+	return ptrace(PTRACE_PEEKUSR_AREA, pid, uintptr(unsafe.Pointer(&parea)), 0)
 }
 
 func PtraceSetRegs(pid int, regs *PtraceRegs) (err error) {
-	return ptrace(PTRACE_SETREGS, pid, 0, uintptr(unsafe.Pointer(regs)))
+	parea := _ptrace_area{
+		_sizeof_ptrace_area,
+		0,
+		uint64(uintptr(unsafe.Pointer(regs))),
+	}
+	return ptrace(PTRACE_POKEUSR_AREA, pid, uintptr(unsafe.Pointer(&parea)), 0)
 }
--- libgo/go/syscall/syscall_linux_s390.go	(revision 250173)
+++ libgo/go/syscall/syscall_linux_s390.go	(revision 250174)
@@ -4,18 +4,30 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// See the s390x version for why we don't use GETREGSET/SETREGSET
+
 package syscall
 
 import "unsafe"
 
-func (r *PtraceRegs) PC() uint64 { return uint64(r.Psw.Addr) }
+func (r *PtraceRegs) PC() uint64 { return uint64(r.Psw.addr) }
 
-func (r *PtraceRegs) SetPC(pc uint64) { r.Psw.Addr = uint32(pc) }
+func (r *PtraceRegs) SetPC(pc uint64) { r.Psw.addr = uint32(pc) }
 
-func PtraceGetRegs(pid int, regsout *PtraceRegs) (err error) {
-	return ptrace(PTRACE_GETREGS, pid, 0, uintptr(unsafe.Pointer(regsout)))
+func PtraceGetRegs(pid int, regs *PtraceRegs) (err error) {
+	parea := _ptrace_area{
+		_sizeof_ptrace_area,
+		0,
+		uint32(uintptr(unsafe.Pointer(regs))),
+	}
+	return ptrace(PTRACE_PEEKUSR_AREA, pid, uintptr(unsafe.Pointer(&parea)), 0)
 }
 
 func PtraceSetRegs(pid int, regs *PtraceRegs) (err error) {
-	return ptrace(PTRACE_SETREGS, pid, 0, uintptr(unsafe.Pointer(regs)))
+	parea := _ptrace_area{
+		_sizeof_ptrace_area,
+		0,
+		uint32(uintptr(unsafe.Pointer(regs))),
+	}
+	return ptrace(PTRACE_POKEUSR_AREA, pid, uintptr(unsafe.Pointer(&parea)), 0)
 }
--- libgo/configure	(revision 249471)
+++ libgo/configure	(revision 249472)
@@ -14782,7 +14782,7 @@ $as_echo "#define HAVE_GETIPINFO 1" >>co
   fi
 
 
-for ac_header in port.h sched.h semaphore.h sys/file.h sys/mman.h syscall.h sys/epoll.h sys/event.h sys/inotify.h sys/ptrace.h sys/syscall.h sys/user.h sys/utsname.h sys/select.h sys/socket.h net/if.h net/if_arp.h net/route.h netpacket/packet.h sys/prctl.h sys/mount.h sys/vfs.h sys/statfs.h sys/timex.h sys/sysinfo.h utime.h linux/ether.h linux/fs.h linux/reboot.h netinet/icmp6.h netinet/in_syst.h netinet/ip.h netinet/ip_mroute.h netinet/if_ether.h
+for ac_header in port.h sched.h semaphore.h sys/file.h sys/mman.h syscall.h sys/epoll.h sys/event.h sys/inotify.h sys/ptrace.h sys/syscall.h sys/user.h sys/utsname.h sys/select.h sys/socket.h net/if.h net/if_arp.h net/route.h netpacket/packet.h sys/prctl.h sys/mount.h sys/vfs.h sys/statfs.h sys/timex.h sys/sysinfo.h utime.h linux/ether.h linux/fs.h linux/ptrace.h linux/reboot.h netinet/icmp6.h netinet/in_syst.h netinet/ip.h netinet/ip_mroute.h netinet/if_ether.h
 do :
   as_ac_Header=`$as_echo "ac_cv_header_$ac_header" | $as_tr_sh`
 ac_fn_c_check_header_mongrel "$LINENO" "$ac_header" "$as_ac_Header" "$ac_includes_default"
--- libgo/config.h.in	(revision 249471)
+++ libgo/config.h.in	(revision 249472)
@@ -114,6 +114,9 @@
 /* Define to 1 if you have the <linux/netlink.h> header file. */
 #undef HAVE_LINUX_NETLINK_H
 
+/* Define to 1 if you have the <linux/ptrace.h> header file. */
+#undef HAVE_LINUX_PTRACE_H
+
 /* Define to 1 if you have the <linux/reboot.h> header file. */
 #undef HAVE_LINUX_REBOOT_H