diff --git a/NEWS b/NEWS
index 8727b5e7f0..0b1476e745 100644
--- a/NEWS
+++ b/NEWS
@@ -34,6 +34,30 @@ Deprecated and removed features, and other changes affecting compatibility:
   binaries and it has been removed from <time.h> header.  This function
   has been deprecated in favor of clock_settime.
 
+* The settimeofday function can still be used to set a system-wide time
+  zone when the operating system supports it.  This is because the Linux
+  kernel reused the API, on some architectures, to describe a system-wide
+  time-zone-like offset between the software clock maintained by the kernel,
+  and the â€œRTCâ€ clock that keeps time when the system is shut down.
+
+  However, to reduce the odds of this offset being set by accident,
+  settimeofday can no longer be used to set the time and the offset
+  simultaneously.  If both of its two arguments are non-null, the call
+  will fail (setting errno to EINVAL).
+
+  Callers attempting to set this offset should also be prepared for the call
+  to fail and set errno to ENOSYS; this already happens on the Hurd and on
+  some Linux architectures.  The Linux kernel maintainers are discussing a
+  more principled replacement for the reused API.  After a replacement
+  becomes available, we will change settimeofday to fail with ENOSYS on all
+  platforms when its â€˜tzpâ€™ argument is not a null pointer.
+
+  Note that settimeofday itself is obsolescent according to POSIX.
+  Programs that set the system time should use clock_settime and/or
+  the adjtime family of functions instead.  We may also cease to make
+  settimeofday available to newly linked binaries after there is a
+  replacement for Linuxâ€™s time-zone-like offset API.
+
 Changes to build and runtime requirements:
 
   [Add changes to build and runtime requirements here]
diff --git a/include/sys/time.h b/include/sys/time.h
index 57208afa82..c0e30e70fb 100644
--- a/include/sys/time.h
+++ b/include/sys/time.h
@@ -24,8 +24,7 @@ extern int __gettimeofday (struct timeval *__tv,
 			   struct timezone *__tz);
 libc_hidden_proto (__gettimeofday)
 libc_hidden_proto (gettimeofday)
-extern int __settimeofday (const struct timeval *__tv,
-			   const struct timezone *__tz)
+extern int __settimezone (const struct timezone *__tz)
 	attribute_hidden;
 extern int __adjtime (const struct timeval *__delta,
 		      struct timeval *__olddelta);
diff --git a/sysdeps/unix/clock_settime.c b/sysdeps/mach/hurd/clock_settime.c
similarity index 65%
rename from sysdeps/unix/clock_settime.c
rename to sysdeps/mach/hurd/clock_settime.c
index 18d7c99864..02239c097a 100644
--- a/sysdeps/unix/clock_settime.c
+++ b/sysdeps/mach/hurd/clock_settime.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1999-2019 Free Software Foundation, Inc.
+/* Copyright (C) 1991-2019 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -17,38 +17,31 @@
 
 #include <errno.h>
 #include <time.h>
-#include <sys/time.h>
+#include <hurd.h>
+#include <hurd/port.h>
 #include <shlib-compat.h>
 
-/* Set CLOCK to value TP.  */
+/* Set the current time of day.
+   This call is restricted to the super-user.  */
 int
-__clock_settime (clockid_t clock_id, const struct timespec *tp)
+__clock_settime (clockid_t clock_id, const struct timespec *ts)
 {
-  int retval = -1;
-
-  /* Make sure the time cvalue is OK.  */
-  if (tp->tv_nsec < 0 || tp->tv_nsec >= 1000000000)
-    {
-      __set_errno (EINVAL);
-      return -1;
-    }
-
-  switch (clock_id)
-    {
-    case CLOCK_REALTIME:
-      {
-	struct timeval tv;
-	TIMESPEC_TO_TIMEVAL (&tv, tp);
-	retval = __settimeofday (&tv, NULL);
-      }
-      break;
-
-    default:
-      __set_errno (EINVAL);
-      break;
-    }
-
-  return retval;
+  error_t err;
+  mach_port_t hostpriv;
+  time_value_t tv;
+
+  if (clock_id != CLOCK_REALTIME)
+    return __hurd_fail (EINVAL);
+
+  err = __get_privileged_ports (&hostpriv, NULL);
+  if (err)
+    return __hurd_fail (EPERM);
+
+  TIMESPEC_TO_TIME_VALUE (&tv, ts);
+  err = __host_set_time (hostpriv, tv);
+  __mach_port_deallocate (__mach_task_self (), hostpriv);
+
+  return __hurd_fail (err);
 }
 libc_hidden_def (__clock_settime)
 
diff --git a/sysdeps/unix/syscalls.list b/sysdeps/unix/syscalls.list
index 61e5360b4d..5fedd5733d 100644
--- a/sysdeps/unix/syscalls.list
+++ b/sysdeps/unix/syscalls.list
@@ -76,7 +76,6 @@ setreuid	-	setreuid	i:ii	__setreuid	setreuid
 setrlimit	-	setrlimit	i:ip	__setrlimit setrlimit
 setsid		-	setsid		i:	__setsid	setsid
 setsockopt	-	setsockopt	i:iiibn	setsockopt	__setsockopt
-settimeofday	-	settimeofday	i:PP	__settimeofday	settimeofday
 setuid		-	setuid		i:i	__setuid	setuid
 shutdown	-	shutdown	i:ii	shutdown
 sigaction	-	sigaction	i:ipp	__sigaction	sigaction
diff --git a/sysdeps/unix/sysv/linux/alpha/osf_settimeofday.c b/sysdeps/unix/sysv/linux/alpha/osf_settimeofday.c
index fb2a36df19..914f5ac57b 100644
--- a/sysdeps/unix/sysv/linux/alpha/osf_settimeofday.c
+++ b/sysdeps/unix/sysv/linux/alpha/osf_settimeofday.c
@@ -32,9 +32,19 @@ attribute_compat_text_section
 __settimeofday_tv32 (const struct timeval32 *tv32,
                      const struct timezone *tz)
 {
-  struct timeval tv;
-  tv32_to_tv64 (&tv, tv32);
-  return __settimeofday (&tv, tz);
+  if (__glibc_unlikely (tz != 0))
+    {
+      if (tv32 != 0)
+	{
+	  __set_errno (EINVAL);
+	  return -1;
+	}
+      return __settimezone (tz);
+    }
+
+  struct timespec ts;
+  tv32_to_ts64 (&ts, tv32);
+  return __clock_settime (CLOCK_REALTIME, &ts);
 }
 
 compat_symbol (libc, __settimeofday_tv32, settimeofday, GLIBC_2_0);
diff --git a/sysdeps/unix/sysv/linux/alpha/settimeofday.c b/sysdeps/unix/sysv/linux/alpha/settimeofday.c
new file mode 100644
index 0000000000..36a6901e4e
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/alpha/settimeofday.c
@@ -0,0 +1,22 @@
+/* settimeofday -- Set the current time of day.  Linux/Alpha/tv64 version.
+   Copyright (C) 2019 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* We can use the generic implementation, but we have to override its
+   default symbol version.  */
+#define VERSION_settimeofday GLIBC_2.1
+#include <time/settimeofday.c>
diff --git a/sysdeps/unix/sysv/linux/alpha/syscalls.list b/sysdeps/unix/sysv/linux/alpha/syscalls.list
index c786aa751e..95a27e18e8 100644
--- a/sysdeps/unix/sysv/linux/alpha/syscalls.list
+++ b/sysdeps/unix/sysv/linux/alpha/syscalls.list
@@ -24,7 +24,6 @@ pciconfig_iobase EXTRA	pciconfig_iobase 3	__pciconfig_iobase pciconfig_iobase
 
 # timeval64 entry points (see osf_*.c for GLIBC_2.0 timeval32 equivalents)
 gettimeofday	-	gettimeofday	i:pP	__GI___gettimeofday gettimeofday@@GLIBC_2.1 __gettimeofday@@GLIBC_2.1
-settimeofday	-	settimeofday	i:PP	__settimeofday	settimeofday@@GLIBC_2.1
 getitimer	-	getitimer	i:ip	__getitimer	getitimer@@GLIBC_2.1
 setitimer	-	setitimer	i:ipP	__setitimer	setitimer@@GLIBC_2.1
 utimes		-	utimes		i:sp	__utimes	utimes@@GLIBC_2.1
diff --git a/sysdeps/unix/sysv/linux/settimezone.c b/sysdeps/unix/sysv/linux/settimezone.c
new file mode 100644
index 0000000000..90b38307c6
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/settimezone.c
@@ -0,0 +1,36 @@
+/* Obsolete set system time.  Linux version.
+   Copyright (C) 2019 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <sys/time.h>
+#include <sysdep.h>
+
+/* Set the system-wide timezone.
+   This call is restricted to the super-user.
+   This operation is considered obsolete, kernel support may not be
+   available on all architectures.  */
+int
+__settimezone (const struct timezone *tz)
+{
+#ifdef __NR_settimeofday
+  return INLINE_SYSCALL_CALL (settimeofday, NULL, tz);
+#else
+  __set_errno (ENOSYS);
+  return -1
+#endif
+}
diff --git a/time/Makefile b/time/Makefile
index ad8844ea34..6de4e418d9 100644
--- a/time/Makefile
+++ b/time/Makefile
@@ -31,13 +31,13 @@ headers := time.h sys/time.h sys/timeb.h bits/time.h			\
 
 routines := offtime asctime clock ctime ctime_r difftime \
 	    gmtime localtime mktime time		 \
-	    gettimeofday settimeofday adjtime tzset	 \
-	    tzfile getitimer setitimer			 \
+	    gettimeofday settimeofday settimezone	 \
+	    adjtime tzset tzfile getitimer setitimer	 \
 	    stime dysize timegm ftime			 \
 	    getdate strptime strptime_l			 \
 	    strftime wcsftime strftime_l wcsftime_l	 \
-	    timespec_get 	 			 \
-	    clock_getcpuclockid clock_getres 		 \
+	    timespec_get				 \
+	    clock_getcpuclockid clock_getres		 \
 	    clock_gettime clock_settime clock_nanosleep
 
 aux :=	    era alt_digit lc-time-cleanup
diff --git a/time/settimeofday.c b/time/settimeofday.c
index 6aa4832d65..ad57ad41a1 100644
--- a/time/settimeofday.c
+++ b/time/settimeofday.c
@@ -16,6 +16,7 @@
    <https://www.gnu.org/licenses/>.  */
 
 #include <errno.h>
+#include <time.h>
 #include <sys/time.h>
 
 /* Set the current time of day and timezone information.
@@ -23,9 +24,24 @@
 int
 __settimeofday (const struct timeval *tv, const struct timezone *tz)
 {
-  __set_errno (ENOSYS);
-  return -1;
+  if (__glibc_unlikely (tz != 0))
+    {
+      if (tv != 0)
+	{
+	  __set_errno (EINVAL);
+	  return -1;
+	}
+      return __settimezone (tz);
+    }
+
+  struct timespec ts;
+  TIMEVAL_TO_TIMESPEC (tv, &ts);
+  return __clock_settime (CLOCK_REALTIME, &ts);
 }
-stub_warning (settimeofday)
 
-weak_alias (__settimeofday, settimeofday)
+#ifdef VERSION_settimeofday
+weak_alias (__settimeofday, __settimeofday_w);
+default_symbol_version (__settimeofday_w, settimeofday, VERSION_settimeofday);
+#else
+weak_alias (__settimeofday, settimeofday);
+#endif
diff --git a/sysdeps/mach/hurd/settimeofday.c b/time/settimezone.c
similarity index 52%
rename from sysdeps/mach/hurd/settimeofday.c
rename to time/settimezone.c
index 31bffcad9d..b9969c9dd5 100644
--- a/sysdeps/mach/hurd/settimeofday.c
+++ b/time/settimezone.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1991-2019 Free Software Foundation, Inc.
+/* Copyright (C) 2019 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -17,36 +17,12 @@
 
 #include <errno.h>
 #include <sys/time.h>
-#include <hurd.h>
-#include <hurd/port.h>
 
-/* Set the current time of day and timezone information.
+/* Set the system-wide timezone.
    This call is restricted to the super-user.  */
 int
-__settimeofday (const struct timeval *tv, const struct timezone *tz)
+__settimezone (const struct timezone *tz)
 {
-  error_t err;
-  mach_port_t hostpriv;
-
-  if (tz != NULL)
-    {
-      errno = ENOSYS;
-      return -1;
-    }
-
-  err = __get_privileged_ports (&hostpriv, NULL);
-  if (err)
-    return __hurd_fail (EPERM);
-
-  /* `time_value_t' and `struct timeval' are in fact identical with the
-     names changed.  */
-  err = __host_set_time (hostpriv, *(time_value_t *) tv);
-  __mach_port_deallocate (__mach_task_self (), hostpriv);
-
-  if (err)
-    return __hurd_fail (err);
-
-  return 0;
+  __set_errno (ENOSYS);
+  return -1;
 }
-
-weak_alias (__settimeofday, settimeofday)
