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authorZack Weinberg <zackw@panix.com>2018-04-03 18:26:44 -0400
committerPranav Kant <prka@google.com>2024-06-11 00:00:26 +0000
commit98f5e8eb9613399ceeaadeb46acb61fa99a34ab5 (patch)
treef19836947c176306b55e4e420795af819f66f600
parente00ff0233807361ff898817c6f355806fe569a81 (diff)
downloadglibc-pranavk/grte_v5_plus.tar.gz
glibc-pranavk/grte_v5_plus.tar.xz
glibc-pranavk/grte_v5_plus.zip
Avoid cancellable I/O primitives in ld.so. pranavk/grte_v5_plus
Neither the <dlfcn.h> entry points, nor lazy symbol resolution, nor
initial shared library load-up, are cancellation points, so ld.so
should exclusively use I/O primitives that are not cancellable.  We
currently achieve this by having the cancellation hooks compile as
no-ops when IS_IN(rtld); this patch changes to using exclusively
_nocancel primitives in the source code instead, which makes the
intent clearer and significantly reduces the amount of code compiled
under IS_IN(rtld) as well as IS_IN(libc) -- in particular,
elf/Makefile no longer thinks we require a copy of unwind.c in
rtld-libc.a.  (The older mechanism is preserved as a backstop.)

The bulk of the change is splitting up the files that define the
_nocancel I/O functions, so they don't also define the variants that
*are* cancellation points; after which, the existing logic for picking
out the bits of libc that need to be recompiled as part of ld.so Just
Works.  I did this for all of the _nocancel functions, not just the
ones used by ld.so, for consistency.

fcntl was a little tricky because it's only a cancellation point for
certain opcodes (F_SETLKW(64), which can block), and the existing
__fcntl_nocancel wasn't applying the FCNTL_ADJUST_CMD hook, which
strikes me as asking for trouble, especially as the only nontrivial
definition of FCNTL_ADJUST_CMD (for powerpc64) changes F_*LK* opcodes.
To fix this, fcntl_common moves to fcntl_nocancel.c along with
__fcntl_nocancel, and changes its name to the extern (but hidden)
symbol __fcntl_nocancel_adjusted, so that regular fcntl can continue
calling it.  __fcntl_nocancel now applies FCNTL_ADJUST_CMD; so that
both both fcntl.c and fcntl_nocancel.c can see it, the only nontrivial
definition moves from sysdeps/u/s/l/powerpc/powerpc64/fcntl.c to
.../powerpc64/sysdep.h and becomes entirely a macro, instead of a macro
that calls an inline function.

The nptl version of libpthread also changes a little, because its
"compat-routines" formerly included files that defined all the
_nocancel functions it uses; instead of continuing to duplicate them,
I exported the relevant ones from libc.so as GLIBC_PRIVATE.  Since the
Linux fcntl.c calls a function defined by fcntl_nocancel.c, it can no
longer be used from libpthread.so; instead, introduce a custom
forwarder, pt-fcntl.c, and export __libc_fcntl from libc.so as
GLIBC_PRIVATE.  The nios2-linux ABI doesn't include a copy of vfork()
in libpthread, and it was handling that by manipulating
libpthread-routines in .../linux/nios2/Makefile; it is cleaner to do
what other such ports do, and have a pt-vfork.S that defines no symbols.

Right now, it appears that Hurd does not implement _nocancel I/O, so
sysdeps/generic/not-cancel.h will forward everything back to the
regular functions.  This changed the names of some of the functions
that sysdeps/mach/hurd/dl-sysdep.c needs to interpose.

	* elf/dl-load.c, elf/dl-misc.c, elf/dl-profile.c, elf/rtld.c
	* sysdeps/unix/sysv/linux/dl-sysdep.c
	Include not-cancel.h.  Use __close_nocancel instead of __close,
	__open64_nocancel instead of __open, __read_nocancel instead of
	__libc_read, and __write_nocancel instead of __libc_write.

	* csu/check_fds.c (check_one_fd)
	* sysdeps/posix/fdopendir.c (__fdopendir)
	* sysdeps/posix/opendir.c (__alloc_dir): Use __fcntl_nocancel
        instead of __fcntl and/or __libc_fcntl.

	* sysdeps/unix/sysv/linux/pthread_setname.c (pthread_setname_np)
	* sysdeps/unix/sysv/linux/pthread_getname.c (pthread_getname_np)
        * sysdeps/unix/sysv/linux/i386/smp.h (is_smp_system):
	Use __open64_nocancel instead of __open_nocancel.

	* sysdeps/unix/sysv/linux/not-cancel.h: Move all of the
	hidden_proto declarations to the end and issue them if either
	IS_IN(libc) or IS_IN(rtld).
	* sysdeps/unix/sysv/linux/Makefile [subdir=io] (sysdep_routines):
	Add close_nocancel, fcntl_nocancel, nanosleep_nocancel,
	open_nocancel, open64_nocancel, openat_nocancel, pause_nocancel,
	read_nocancel, waitpid_nocancel, write_nocancel.

        * io/Versions [GLIBC_PRIVATE]: Add __libc_fcntl,
        __fcntl_nocancel, __open64_nocancel, __write_nocancel.
        * posix/Versions: Add __nanosleep_nocancel, __pause_nocancel.

        * nptl/pt-fcntl.c: New file.
        * nptl/Makefile (pthread-compat-wrappers): Remove fcntl.
        (libpthread-routines): Add pt-fcntl.
        * include/fcntl.h (__fcntl_nocancel_adjusted): New function.
        (__libc_fcntl): Remove attribute_hidden.
	* sysdeps/unix/sysv/linux/fcntl.c (__libc_fcntl): Call
	__fcntl_nocancel_adjusted, not fcntl_common.
        (__fcntl_nocancel): Move to new file fcntl_nocancel.c.
	(fcntl_common): Rename to __fcntl_nocancel_adjusted; also move
	to fcntl_nocancel.c.
	* sysdeps/unix/sysv/linux/fcntl_nocancel.c: New file.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/fcntl.c: Remove file.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h:
	Define FCNTL_ADJUST_CMD here, as a self-contained macro.

	* sysdeps/unix/sysv/linux/close.c: Move __close_nocancel to...
	* sysdeps/unix/sysv/linux/close_nocancel.c: ...this new file.
	* sysdeps/unix/sysv/linux/nanosleep.c: Move __nanosleep_nocancel to...
	* sysdeps/unix/sysv/linux/nanosleep_nocancel.c: ...this new file.
	* sysdeps/unix/sysv/linux/open.c: Move __open_nocancel to...
	* sysdeps/unix/sysv/linux/open_nocancel.c: ...this new file.
	* sysdeps/unix/sysv/linux/open64.c: Move __open64_nocancel to...
	* sysdeps/unix/sysv/linux/open64_nocancel.c: ...this new file.
	* sysdeps/unix/sysv/linux/openat.c: Move __openat_nocancel to...
	* sysdeps/unix/sysv/linux/openat_nocancel.c: ...this new file.
	* sysdeps/unix/sysv/linux/openat64.c: Move __openat64_nocancel to...
	* sysdeps/unix/sysv/linux/openat64_nocancel.c: ...this new file.
	* sysdeps/unix/sysv/linux/pause.c: Move __pause_nocancel to...
	* sysdeps/unix/sysv/linux/pause_nocancel.c: ...this new file.
	* sysdeps/unix/sysv/linux/read.c: Move __read_nocancel to...
	* sysdeps/unix/sysv/linux/read_nocancel.c: ...this new file.
	* sysdeps/unix/sysv/linux/waitpid.c: Move __waitpid_nocancel to...
	* sysdeps/unix/sysv/linux/waitpid_nocancel.c: ...this new file.
	* sysdeps/unix/sysv/linux/write.c: Move __write_nocancel to...
	* sysdeps/unix/sysv/linux/write_nocancel.c: ...this new file.

        * sysdeps/unix/sysv/linux/nios2/Makefile: Don't override
        libpthread-routines.
        * sysdeps/unix/sysv/linux/nios2/pt-vfork.S: New file which
        defines nothing.

        * sysdeps/mach/hurd/dl-sysdep.c: Define __read instead of
        __libc_read, and __write instead of __libc_write.  Define
        __open64 in addition to __open.

(cherry picked from commit 329ea513b451ae8322aa7a24ed84da13992af2dd)
-rw-r--r--csu/check_fds.c3
-rw-r--r--elf/dl-load.c34
-rw-r--r--elf/dl-misc.c6
-rw-r--r--elf/dl-profile.c14
-rw-r--r--elf/rtld.c3
-rw-r--r--include/fcntl.h3
-rw-r--r--io/Versions6
-rw-r--r--nptl/Makefile4
-rw-r--r--posix/Versions1
-rw-r--r--sysdeps/mach/hurd/dl-sysdep.c14
-rw-r--r--sysdeps/posix/fdopendir.c2
-rw-r--r--sysdeps/posix/opendir.c2
-rw-r--r--sysdeps/unix/pt-fcntl.c49
-rw-r--r--sysdeps/unix/sysv/linux/Makefile7
-rw-r--r--sysdeps/unix/sysv/linux/close.c11
-rw-r--r--sysdeps/unix/sysv/linux/close_nocancel.c (renamed from sysdeps/unix/sysv/linux/powerpc/powerpc64/fcntl.c)20
-rw-r--r--sysdeps/unix/sysv/linux/dl-sysdep.c7
-rw-r--r--sysdeps/unix/sysv/linux/fcntl.c41
-rw-r--r--sysdeps/unix/sysv/linux/fcntl_nocancel.c65
-rw-r--r--sysdeps/unix/sysv/linux/i386/smp.h2
-rw-r--r--sysdeps/unix/sysv/linux/nanosleep.c10
-rw-r--r--sysdeps/unix/sysv/linux/nanosleep_nocancel.c29
-rw-r--r--sysdeps/unix/sysv/linux/nios2/Makefile4
-rw-r--r--sysdeps/unix/sysv/linux/nios2/pt-vfork.S1
-rw-r--r--sysdeps/unix/sysv/linux/not-cancel.h25
-rw-r--r--sysdeps/unix/sysv/linux/open.c25
-rw-r--r--sysdeps/unix/sysv/linux/open64.c30
-rw-r--r--sysdeps/unix/sysv/linux/open64_nocancel.c54
-rw-r--r--sysdeps/unix/sysv/linux/open_nocancel.c46
-rw-r--r--sysdeps/unix/sysv/linux/openat.c24
-rw-r--r--sysdeps/unix/sysv/linux/openat64.c27
-rw-r--r--sysdeps/unix/sysv/linux/openat64_nocancel.c51
-rw-r--r--sysdeps/unix/sysv/linux/openat_nocancel.c43
-rw-r--r--sysdeps/unix/sysv/linux/pause.c12
-rw-r--r--sysdeps/unix/sysv/linux/pause_nocancel.c33
-rw-r--r--sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h9
-rw-r--r--sysdeps/unix/sysv/linux/pthread_getname.c2
-rw-r--r--sysdeps/unix/sysv/linux/pthread_setname.c2
-rw-r--r--sysdeps/unix/sysv/linux/read.c12
-rw-r--r--sysdeps/unix/sysv/linux/read_nocancel.c28
-rw-r--r--sysdeps/unix/sysv/linux/waitpid.c15
-rw-r--r--sysdeps/unix/sysv/linux/waitpid_nocancel.c34
-rw-r--r--sysdeps/unix/sysv/linux/write.c12
-rw-r--r--sysdeps/unix/sysv/linux/write_nocancel.c28
44 files changed, 572 insertions, 278 deletions
diff --git a/csu/check_fds.c b/csu/check_fds.c
index 2b181d44ab..605ee4f3f4 100644
--- a/csu/check_fds.c
+++ b/csu/check_fds.c
@@ -39,8 +39,7 @@
 static void
 check_one_fd (int fd, int mode)
 {
-  /* Note that fcntl() with this parameter is not a cancellation point.  */
-  if (__builtin_expect (__libc_fcntl (fd, F_GETFD), 0) == -1
+  if (__builtin_expect (__fcntl_nocancel (fd, F_GETFD), 0) == -1
       && errno == EBADF)
     {
       const char *name;
diff --git a/elf/dl-load.c b/elf/dl-load.c
index 957f1b9b30..5369410d83 100644
--- a/elf/dl-load.c
+++ b/elf/dl-load.c
@@ -48,6 +48,7 @@
 
 /* Code below to add offset to symbol names references itoa.  */
 #include <_itoa.h>
+#include <not-cancel.h>
 
 #include <endian.h>
 #if BYTE_ORDER == BIG_ENDIAN
@@ -786,7 +787,7 @@ lose (int code, int fd, const char *name, char *realname, struct link_map *l,
 {
   /* The file might already be closed.  */
   if (fd != -1)
-    (void) __close (fd);
+    (void) __close_nocancel (fd);
   if (l != NULL && l->l_origin != (char *) -1l)
     free ((char *) l->l_origin);
   free (l);
@@ -1016,7 +1017,7 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd, off_t of
     {
       /* The object is already loaded.
          Just bump its reference count and return it.  */
-      __close (fd);
+      __close_nocancel (fd);
 
       free (realname);
 
@@ -1045,7 +1046,7 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd, off_t of
 
       /* No need to bump the refcount of the real object, ld.so will
 	 never be unloaded.  */
-      __close (fd);
+      __close_nocancel (fd);
 
       /* Add the map for the mirrored object to the object list.  */
       _dl_add_to_namespace_list (l, nsid);
@@ -1059,7 +1060,7 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd, off_t of
       /* We are not supposed to load the object unless it is already
 	 loaded.  So return now.  */
       free (realname);
-      __close (fd);
+      __close_nocancel (fd);
       return NULL;
     }
 
@@ -1078,7 +1079,7 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd, off_t of
       if (_dl_zerofd == -1)
 	{
 	  free (realname);
-	  __close (fd);
+	  __close_nocancel (fd);
 	  _dl_signal_error (errno, NULL, NULL,
 			    N_("cannot open zero fill device"));
 	}
@@ -1165,7 +1166,7 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd, off_t of
     {
       phdr = alloca (maplength);
       __lseek (fd, header->e_phoff, SEEK_SET);
-      if ((size_t) __libc_read (fd, (void *) phdr, maplength) != maplength)
+      if ((size_t) __read_nocancel (fd, (void *) phdr, maplength) != maplength)
 	{
 	  errstring = N_("cannot read file data");
 	  goto call_lose_errno;
@@ -1446,7 +1447,7 @@ cannot enable executable stack as shared object requires");
     l->l_tls_initimage = (char *) l->l_tls_initimage + l->l_addr;
 
   /* We are done mapping in the file.  We no longer need the descriptor.  */
-  if (__glibc_unlikely (__close (fd) != 0))
+  if (__glibc_unlikely (__close_nocancel (fd) != 0))
     {
       errstring = N_("cannot close file descriptor");
       goto call_lose_errno;
@@ -1660,7 +1661,7 @@ open_verify (const char *name, int fd, off_t offset,
         {
           /* An audit library changed what we're supposed to open,
              so FD no longer matches it.  */
-          __close (fd);
+          __close_nocancel (fd);
           fd = -1;
         }
     }
@@ -1668,7 +1669,7 @@ open_verify (const char *name, int fd, off_t offset,
 
   if (fd == -1)
     /* Open the file.  We always open files read-only.  */
-    fd = __open (name, O_RDONLY | O_CLOEXEC);
+    fd = __open64_nocancel (name, O_RDONLY | O_CLOEXEC);
 
   if (fd != -1)
     {
@@ -1690,8 +1691,8 @@ open_verify (const char *name, int fd, off_t offset,
       /* Read in the header.  */
       do
 	{
-	  ssize_t retlen = __libc_read (fd, fbp->buf + fbp->len,
-					sizeof (fbp->buf) - fbp->len);
+	  ssize_t retlen = __read_nocancel (fd, fbp->buf + fbp->len,
+					    sizeof (fbp->buf) - fbp->len);
 	  if (retlen <= 0)
 	    break;
 	  fbp->len += retlen;
@@ -1814,7 +1815,8 @@ open_verify (const char *name, int fd, off_t offset,
 	{
 	  phdr = alloca (maplength);
 	  __lseek (fd, ehdr->e_phoff, SEEK_SET);
-	  if ((size_t) __libc_read (fd, (void *) phdr, maplength) != maplength)
+	  if ((size_t) __read_nocancel (fd, (void *) phdr, maplength)
+	      != maplength)
 	    {
 	    read_error:
 	      errval = errno;
@@ -1864,7 +1866,7 @@ open_verify (const char *name, int fd, off_t offset,
 		    abi_note = abi_note_malloced;
 		  }
 		__lseek (fd, ph->p_offset, SEEK_SET);
-		if (__libc_read (fd, (void *) abi_note, size) != size)
+		if (__read_nocancel (fd, (void *) abi_note, size) != size)
 		  {
 		    free (abi_note_malloced);
 		    goto read_error;
@@ -1896,7 +1898,7 @@ open_verify (const char *name, int fd, off_t offset,
 		|| (GLRO(dl_osversion) && GLRO(dl_osversion) < osversion))
 	      {
 	      close_and_out:
-		__close (fd);
+		__close_nocancel (fd);
 		__set_errno (ENOENT);
 		fd = -1;
 	      }
@@ -2013,7 +2015,7 @@ open_path (const char *name, size_t namelen, off_t offset, int mode,
 		  /* The shared object cannot be tested for being SUID
 		     or this bit is not set.  In this case we must not
 		     use this object.  */
-		  __close (fd);
+		  __close_nocancel (fd);
 		  fd = -1;
 		  /* We simply ignore the file, signal this by setting
 		     the error value which would have been set by `open'.  */
@@ -2034,7 +2036,7 @@ open_path (const char *name, size_t namelen, off_t offset, int mode,
 	    {
 	      /* No memory for the name, we certainly won't be able
 		 to load and link it.  */
-	      __close (fd);
+	      __close_nocancel (fd);
 	      return -1;
 	    }
 	}
diff --git a/elf/dl-misc.c b/elf/dl-misc.c
index ed9039477d..1cf06b6a15 100644
--- a/elf/dl-misc.c
+++ b/elf/dl-misc.c
@@ -33,7 +33,7 @@
 #include <sysdep.h>
 #include <_itoa.h>
 #include <dl-writev.h>
-
+#include <not-cancel.h>
 
 /* Read the whole contents of FILE into new mmap'd space with given
    protections.  *SIZEP gets the size of the file.  On error MAP_FAILED
@@ -44,7 +44,7 @@ _dl_sysdep_read_whole_file (const char *file, size_t *sizep, int prot)
 {
   void *result = MAP_FAILED;
   struct stat64 st;
-  int fd = __open (file, O_RDONLY | O_CLOEXEC);
+  int fd = __open64_nocancel (file, O_RDONLY | O_CLOEXEC);
   if (fd >= 0)
     {
       if (__fxstat64 (_STAT_VER, fd, &st) >= 0)
@@ -65,7 +65,7 @@ _dl_sysdep_read_whole_file (const char *file, size_t *sizep, int prot)
 #endif
 			     , fd, 0);
 	}
-      __close (fd);
+      __close_nocancel (fd);
     }
   return result;
 }
diff --git a/elf/dl-profile.c b/elf/dl-profile.c
index 7f15352123..bac3718c11 100644
--- a/elf/dl-profile.c
+++ b/elf/dl-profile.c
@@ -35,6 +35,7 @@
 #include <sys/param.h>
 #include <sys/stat.h>
 #include <atomic.h>
+#include <not-cancel.h>
 
 /* The LD_PROFILE feature has to be implemented different to the
    normal profiling using the gmon/ functions.  The problem is that an
@@ -324,7 +325,7 @@ _dl_start_profile (void)
   *cp++ = '/';
   __stpcpy (__stpcpy (cp, GLRO(dl_profile)), ".profile");
 
-  fd = __open (filename, O_RDWR | O_CREAT | O_NOFOLLOW, DEFFILEMODE);
+  fd = __open64_nocancel (filename, O_RDWR|O_CREAT|O_NOFOLLOW, DEFFILEMODE);
   if (fd == -1)
     {
       char buf[400];
@@ -335,7 +336,7 @@ _dl_start_profile (void)
     print_error:
       errnum = errno;
       if (fd != -1)
-	__close (fd);
+	__close_nocancel (fd);
       _dl_error_printf (errstr, filename,
 			__strerror_r (errnum, buf, sizeof buf));
       return;
@@ -364,15 +365,14 @@ _dl_start_profile (void)
 	  goto print_error;
 	}
 
-      if (TEMP_FAILURE_RETRY (__libc_write (fd, buf, (expected_size
-						      & (GLRO(dl_pagesize)
-							 - 1))))
+      if (TEMP_FAILURE_RETRY
+	  (__write_nocancel (fd, buf, (expected_size & (GLRO(dl_pagesize) - 1))))
 	  < 0)
 	goto cannot_create;
     }
   else if (st.st_size != expected_size)
     {
-      __close (fd);
+      __close_nocancel (fd);
     wrong_format:
 
       if (addr != NULL)
@@ -392,7 +392,7 @@ _dl_start_profile (void)
     }
 
   /* We don't need the file descriptor anymore.  */
-  __close (fd);
+  __close_nocancel (fd);
 
   /* Pointer to data after the header.  */
   hist = (char *) (addr + 1);
diff --git a/elf/rtld.c b/elf/rtld.c
index 3b60b49fe9..b12b511d37 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -41,6 +41,7 @@
 #include <tls.h>
 #include <stap-probe.h>
 #include <stackinfo.h>
+#include <not-cancel.h>
 
 #include <assert.h>
 
@@ -2756,7 +2757,7 @@ process_envvars (enum mode *modep)
       *--startp = '.';
       startp = memcpy (startp - name_len, debug_output, name_len);
 
-      GLRO(dl_debug_fd) = __open (startp, flags, DEFFILEMODE);
+      GLRO(dl_debug_fd) = __open64_nocancel (startp, flags, DEFFILEMODE);
       if (GLRO(dl_debug_fd) == -1)
 	/* We use standard output if opening the file failed.  */
 	GLRO(dl_debug_fd) = STDOUT_FILENO;
diff --git a/include/fcntl.h b/include/fcntl.h
index 3d68c5ec67..966f797890 100644
--- a/include/fcntl.h
+++ b/include/fcntl.h
@@ -8,8 +8,9 @@ libc_hidden_proto (__open64)
 extern int __libc_open64 (const char *file, int oflag, ...);
 extern int __libc_open (const char *file, int oflag, ...);
 libc_hidden_proto (__libc_open)
-extern int __libc_fcntl (int fd, int cmd, ...) attribute_hidden;
+extern int __libc_fcntl (int fd, int cmd, ...);
 libc_hidden_proto (__libc_fcntl)
+extern int __fcntl_nocancel_adjusted (int fd, int cmd, void *arg) attribute_hidden;
 extern int __open (const char *__file, int __oflag, ...);
 libc_hidden_proto (__open)
 extern int __fcntl (int __fd, int __cmd, ...);
diff --git a/io/Versions b/io/Versions
index 98898cb9d5..4448b7197c 100644
--- a/io/Versions
+++ b/io/Versions
@@ -128,4 +128,10 @@ libc {
   GLIBC_2.27 {
     copy_file_range;
   }
+  GLIBC_PRIVATE {
+    __libc_fcntl;
+    __fcntl_nocancel;
+    __open64_nocancel;
+    __write_nocancel;
+  }
 }
diff --git a/nptl/Makefile b/nptl/Makefile
index fae3c056bf..77ac328a3d 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -36,7 +36,7 @@ shared-only-routines = forward
 # We need to provide certain routines for compatibility with existing
 # binaries.
 pthread-compat-wrappers = \
-		      write read close fcntl accept \
+		      write read close accept \
 		      connect recv recvfrom send \
 		      sendto fsync lseek lseek64 \
 		      msync nanosleep open open64 pause \
@@ -120,7 +120,7 @@ libpthread-routines = nptl-init vars events version pt-interp \
 		      cancellation \
 		      lowlevellock \
 		      lll_timedlock_wait lll_timedwait_tid \
-		      pt-fork pt-vfork \
+		      pt-fork pt-vfork pt-fcntl \
 		      $(pthread-compat-wrappers) \
 		      pt-raise pt-system \
 		      flockfile ftrylockfile funlockfile \
diff --git a/posix/Versions b/posix/Versions
index 65e96870e1..cad4c23e8c 100644
--- a/posix/Versions
+++ b/posix/Versions
@@ -139,5 +139,6 @@ libc {
   }
   GLIBC_PRIVATE {
     __libc_fork; __libc_pread; __libc_pwrite;
+    __nanosleep_nocancel; __pause_nocancel;
   }
 }
diff --git a/sysdeps/mach/hurd/dl-sysdep.c b/sysdeps/mach/hurd/dl-sysdep.c
index ef96df054e..a7ca59e4fb 100644
--- a/sysdeps/mach/hurd/dl-sysdep.c
+++ b/sysdeps/mach/hurd/dl-sysdep.c
@@ -353,6 +353,7 @@ open_file (const char *file_name, int flags,
 }
 
 check_no_hidden(__open);
+check_no_hidden (__open64);
 int weak_function
 __open (const char *file_name, int mode, ...)
 {
@@ -363,6 +364,7 @@ __open (const char *file_name, int mode, ...)
   else
     return (int)port;
 }
+weak_alias (__open, __open64)
 
 check_no_hidden(__close);
 int weak_function
@@ -373,9 +375,9 @@ __close (int fd)
   return 0;
 }
 
-check_no_hidden(__libc_read);
+check_no_hidden(__read);
 __ssize_t weak_function
-__libc_read (int fd, void *buf, size_t nbytes)
+__read (int fd, void *buf, size_t nbytes)
 {
   error_t err;
   char *data;
@@ -395,11 +397,11 @@ __libc_read (int fd, void *buf, size_t nbytes)
 
   return nread;
 }
-libc_hidden_weak (__libc_read)
+libc_hidden_weak (__read)
 
-check_no_hidden(__libc_write);
+check_no_hidden(__write);
 __ssize_t weak_function
-__libc_write (int fd, const void *buf, size_t nbytes)
+__write (int fd, const void *buf, size_t nbytes)
 {
   error_t err;
   mach_msg_type_number_t nwrote;
@@ -412,7 +414,7 @@ __libc_write (int fd, const void *buf, size_t nbytes)
 
   return nwrote;
 }
-libc_hidden_weak (__libc_write)
+libc_hidden_weak (__write)
 
 /* This is only used for printing messages (see dl-misc.c).  */
 check_no_hidden(__writev);
diff --git a/sysdeps/posix/fdopendir.c b/sysdeps/posix/fdopendir.c
index ab4541f7fc..dafb5d20c1 100644
--- a/sysdeps/posix/fdopendir.c
+++ b/sysdeps/posix/fdopendir.c
@@ -38,7 +38,7 @@ __fdopendir (int fd)
     }
 
   /* Make sure the descriptor allows for reading.  */
-  int flags = __fcntl (fd, F_GETFL);
+  int flags = __fcntl_nocancel (fd, F_GETFL);
   if (__glibc_unlikely (flags == -1))
     return NULL;
   if (__glibc_unlikely ((flags & O_ACCMODE) == O_WRONLY))
diff --git a/sysdeps/posix/opendir.c b/sysdeps/posix/opendir.c
index d925804e89..e65a09c1a2 100644
--- a/sysdeps/posix/opendir.c
+++ b/sysdeps/posix/opendir.c
@@ -197,7 +197,7 @@ __alloc_dir (int fd, bool close_fd, int flags, const struct stat64 *statp)
   /* We have to set the close-on-exit flag if the user provided the
      file descriptor.  */
   if (!close_fd
-      && __builtin_expect (__fcntl (fd, F_SETFD, FD_CLOEXEC), 0) < 0)
+      && __glibc_unlikely (__fcntl_nocancel (fd, F_SETFD, FD_CLOEXEC) < 0))
 	goto lose;
 
   const size_t default_allocation = (4 * BUFSIZ < sizeof (struct dirent64)
diff --git a/sysdeps/unix/pt-fcntl.c b/sysdeps/unix/pt-fcntl.c
new file mode 100644
index 0000000000..8113d52b86
--- /dev/null
+++ b/sysdeps/unix/pt-fcntl.c
@@ -0,0 +1,49 @@
+/* ABI compatibility for 'fcntl' symbol in libpthread ABI.
+   Copyright (C) 2018 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 <fcntl.h>
+#include <stdarg.h>
+#include <shlib-compat.h>
+
+/* libpthread once had its own fcntl, though there was no apparent reason
+   for it.  There is no use in having a separate symbol in libpthread, but
+   the historical ABI requires it.  For static linking, there is no need to
+   provide anything here--the libc version will be linked in.  For shared
+   library ABI compatibility, there must be __fcntl and fcntl symbols in
+   libpthread.so.  */
+
+#if SHLIB_COMPAT (libpthread, GLIBC_2_0, GLIBC_2_28)
+
+static int
+fcntl_compat (int fd, int cmd, ...)
+{
+  void *arg;
+  va_list ap;
+  va_start (ap, cmd);
+  arg = va_arg (ap, void *);
+  va_end (ap);
+  return __libc_fcntl (fd, cmd, arg);
+}
+
+weak_alias (fcntl_compat, fcntl_alias)
+compat_symbol (libpthread, fcntl_alias, fcntl, GLIBC_2_0);
+
+weak_alias (fcntl_compat, __fcntl_alias)
+compat_symbol (libpthread, __fcntl_alias, __fcntl, GLIBC_2_0);
+
+#endif
diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile
index 8f19e0efc3..5f99a1c54c 100644
--- a/sysdeps/unix/sysv/linux/Makefile
+++ b/sysdeps/unix/sysv/linux/Makefile
@@ -167,7 +167,12 @@ endif
 
 ifeq ($(subdir),io)
 sysdep_routines += xstatconv internal_statvfs internal_statvfs64 \
-		   sync_file_range fallocate fallocate64
+		   sync_file_range fallocate fallocate64 \
+		   close_nocancel fcntl_nocancel nanosleep_nocancel \
+		   open_nocancel open64_nocancel \
+		   openat_nocancel openat64_nocancel \
+		   pause_nocancel read_nocancel waitpid_nocancel write_nocancel
+
 sysdep_headers += bits/fcntl-linux.h
 
 tests += tst-fallocate tst-fallocate64
diff --git a/sysdeps/unix/sysv/linux/close.c b/sysdeps/unix/sysv/linux/close.c
index c832d27a0f..fa0938bd89 100644
--- a/sysdeps/unix/sysv/linux/close.c
+++ b/sysdeps/unix/sysv/linux/close.c
@@ -29,14 +29,3 @@ __close (int fd)
 libc_hidden_def (__close)
 strong_alias (__close, __libc_close)
 weak_alias (__close, close)
-
-# if !IS_IN (rtld)
-int
-__close_nocancel (int fd)
-{
-  return INLINE_SYSCALL_CALL (close, fd);
-}
-#else
-strong_alias (__libc_close, __close_nocancel)
-#endif
-libc_hidden_def (__close_nocancel)
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/fcntl.c b/sysdeps/unix/sysv/linux/close_nocancel.c
index 48198c1150..7d744f9096 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/fcntl.c
+++ b/sysdeps/unix/sysv/linux/close_nocancel.c
@@ -1,4 +1,5 @@
-/* Copyright (C) 2000-2018 Free Software Foundation, Inc.
+/* Linux close syscall implementation -- non-cancellable.
+   Copyright (C) 2018 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
@@ -16,17 +17,12 @@
    <http://www.gnu.org/licenses/>.  */
 
 #include <unistd.h>
-#include <fcntl.h>
+#include <sysdep-cancel.h>
+#include <not-cancel.h>
 
-static inline int
-fcntl_adjust_cmd (int cmd)
+int
+__close_nocancel (int fd)
 {
-  if (cmd >= F_GETLK64 && cmd <= F_SETLKW64)
-    cmd -= F_GETLK64 - F_GETLK;
-  return cmd;
+  return INLINE_SYSCALL_CALL (close, fd);
 }
-
-#define FCNTL_ADJUST_CMD(__cmd) \
-  fcntl_adjust_cmd (__cmd)
-
-#include <sysdeps/unix/sysv/linux/fcntl.c>
+libc_hidden_def (__close_nocancel)
diff --git a/sysdeps/unix/sysv/linux/dl-sysdep.c b/sysdeps/unix/sysv/linux/dl-sysdep.c
index 18fe7f330a..ea8ba5960e 100644
--- a/sysdeps/unix/sysv/linux/dl-sysdep.c
+++ b/sysdeps/unix/sysv/linux/dl-sysdep.c
@@ -26,6 +26,7 @@
 #include <sys/param.h>
 #include <sys/utsname.h>
 #include <ldsodefs.h>
+#include <not-cancel.h>
 
 #ifdef SHARED
 # define DL_SYSDEP_INIT frob_brk ()
@@ -88,11 +89,11 @@ _dl_discover_osversion (void)
   if (__uname (&uts))
     {
       /* This was not successful.  Now try reading the /proc filesystem.  */
-      int fd = __open ("/proc/sys/kernel/osrelease", O_RDONLY);
+      int fd = __open64_nocancel ("/proc/sys/kernel/osrelease", O_RDONLY);
       if (fd < 0)
 	return -1;
-      ssize_t reslen = __read (fd, bufmem, sizeof (bufmem));
-      __close (fd);
+      ssize_t reslen = __read_nocancel (fd, bufmem, sizeof (bufmem));
+      __close_nocancel (fd);
       if (reslen <= 0)
 	/* This also didn't work.  We give up since we cannot
 	   make sure the library can actually work.  */
diff --git a/sysdeps/unix/sysv/linux/fcntl.c b/sysdeps/unix/sysv/linux/fcntl.c
index a3cb2aea10..e3992dc9d4 100644
--- a/sysdeps/unix/sysv/linux/fcntl.c
+++ b/sysdeps/unix/sysv/linux/fcntl.c
@@ -1,4 +1,5 @@
-/* Copyright (C) 2000-2018 Free Software Foundation, Inc.
+/* Linux fcntl syscall implementation.
+   Copyright (C) 2000-2018 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
@@ -29,24 +30,6 @@
 # define FCNTL_ADJUST_CMD(__cmd) __cmd
 #endif
 
-static int
-fcntl_common (int fd, int cmd, void *arg)
-{
-  if (cmd == F_GETOWN)
-    {
-      INTERNAL_SYSCALL_DECL (err);
-      struct f_owner_ex fex;
-      int res = INTERNAL_SYSCALL_CALL (fcntl64, err, fd, F_GETOWN_EX, &fex);
-      if (!INTERNAL_SYSCALL_ERROR_P (res, err))
-	return fex.type == F_OWNER_GID ? -fex.pid : fex.pid;
-
-      return INLINE_SYSCALL_ERROR_RETURN_VALUE (INTERNAL_SYSCALL_ERRNO (res,
-								    err));
-    }
-
-  return INLINE_SYSCALL_CALL (fcntl64, fd, cmd, (void *) arg);
-}
-
 int
 __libc_fcntl (int fd, int cmd, ...)
 {
@@ -62,28 +45,10 @@ __libc_fcntl (int fd, int cmd, ...)
   if (cmd == F_SETLKW || cmd == F_SETLKW64)
     return SYSCALL_CANCEL (fcntl64, fd, cmd, (void *) arg);
 
-  return fcntl_common (fd, cmd, arg);
+  return __fcntl_nocancel_adjusted (fd, cmd, arg);
 }
 libc_hidden_def (__libc_fcntl)
 
-#if !IS_IN (rtld)
-int
-__fcntl_nocancel (int fd, int cmd, ...)
-{
-  va_list ap;
-  void *arg;
-
-  va_start (ap, cmd);
-  arg = va_arg (ap, void *);
-  va_end (ap);
-
-  return fcntl_common (fd, cmd, arg);
-}
-#else
-strong_alias (__libc_fcntl, __fcntl_nocancel)
-#endif
-libc_hidden_def (__fcntl_nocancel)
-
 weak_alias (__libc_fcntl, __fcntl)
 libc_hidden_weak (__fcntl)
 weak_alias (__libc_fcntl, fcntl)
diff --git a/sysdeps/unix/sysv/linux/fcntl_nocancel.c b/sysdeps/unix/sysv/linux/fcntl_nocancel.c
new file mode 100644
index 0000000000..f50e382c4a
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/fcntl_nocancel.c
@@ -0,0 +1,65 @@
+/* Linux fcntl syscall implementation -- non-cancellable.
+   Copyright (C) 2018 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 <fcntl.h>
+#include <stdarg.h>
+#include <errno.h>
+#include <sysdep-cancel.h>
+#include <not-cancel.h>
+
+#ifndef __NR_fcntl64
+# define __NR_fcntl64 __NR_fcntl
+#endif
+
+#ifndef FCNTL_ADJUST_CMD
+# define FCNTL_ADJUST_CMD(__cmd) __cmd
+#endif
+
+int
+__fcntl_nocancel (int fd, int cmd, ...)
+{
+  va_list ap;
+  void *arg;
+
+  va_start (ap, cmd);
+  arg = va_arg (ap, void *);
+  va_end (ap);
+
+  cmd = FCNTL_ADJUST_CMD (cmd);
+
+  return __fcntl_nocancel_adjusted (fd, cmd, arg);
+}
+hidden_def (__fcntl_nocancel)
+
+int
+__fcntl_nocancel_adjusted (int fd, int cmd, void *arg)
+{
+  if (cmd == F_GETOWN)
+    {
+      INTERNAL_SYSCALL_DECL (err);
+      struct f_owner_ex fex;
+      int res = INTERNAL_SYSCALL_CALL (fcntl64, err, fd, F_GETOWN_EX, &fex);
+      if (!INTERNAL_SYSCALL_ERROR_P (res, err))
+	return fex.type == F_OWNER_GID ? -fex.pid : fex.pid;
+
+      return INLINE_SYSCALL_ERROR_RETURN_VALUE
+        (INTERNAL_SYSCALL_ERRNO (res, err));
+    }
+
+  return INLINE_SYSCALL_CALL (fcntl64, fd, cmd, (void *) arg);
+}
diff --git a/sysdeps/unix/sysv/linux/i386/smp.h b/sysdeps/unix/sysv/linux/i386/smp.h
index 01734b1779..5457bb27d3 100644
--- a/sysdeps/unix/sysv/linux/i386/smp.h
+++ b/sysdeps/unix/sysv/linux/i386/smp.h
@@ -41,7 +41,7 @@ is_smp_system (void)
   else
     {
       /* This was not successful.  Now try reading the /proc filesystem.  */
-      int fd = __open_nocancel ("/proc/sys/kernel/version", O_RDONLY);
+      int fd = __open64_nocancel ("/proc/sys/kernel/version", O_RDONLY);
       if (__builtin_expect (fd, 0) == -1
 	  || __read_nocancel (fd, u.buf, sizeof (u.buf)) <= 0)
 	/* This also didn't work.  We give up and say it's a UP machine.  */
diff --git a/sysdeps/unix/sysv/linux/nanosleep.c b/sysdeps/unix/sysv/linux/nanosleep.c
index 8945837407..56296046ca 100644
--- a/sysdeps/unix/sysv/linux/nanosleep.c
+++ b/sysdeps/unix/sysv/linux/nanosleep.c
@@ -1,4 +1,4 @@
-/* Linux high resolution nanosleep implementation.
+/* Linux nanosleep syscall implementation.
    Copyright (C) 2017-2018 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -29,11 +29,3 @@ __nanosleep (const struct timespec *requested_time,
 }
 hidden_def (__nanosleep)
 weak_alias (__nanosleep, nanosleep)
-
-int
-__nanosleep_nocancel (const struct timespec *requested_time,
-		      struct timespec *remaining)
-{
-  return INLINE_SYSCALL_CALL (nanosleep, requested_time, remaining);
-}
-hidden_def (__nanosleep_nocancel)
diff --git a/sysdeps/unix/sysv/linux/nanosleep_nocancel.c b/sysdeps/unix/sysv/linux/nanosleep_nocancel.c
new file mode 100644
index 0000000000..66f3efd09e
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/nanosleep_nocancel.c
@@ -0,0 +1,29 @@
+/* Linux nanosleep syscall implementation -- non-cancellable.
+   Copyright (C) 2018 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 <time.h>
+#include <sysdep-cancel.h>
+#include <not-cancel.h>
+
+int
+__nanosleep_nocancel (const struct timespec *requested_time,
+		      struct timespec *remaining)
+{
+  return INLINE_SYSCALL_CALL (nanosleep, requested_time, remaining);
+}
+hidden_def (__nanosleep_nocancel)
diff --git a/sysdeps/unix/sysv/linux/nios2/Makefile b/sysdeps/unix/sysv/linux/nios2/Makefile
index d0af9ec559..c22425f087 100644
--- a/sysdeps/unix/sysv/linux/nios2/Makefile
+++ b/sysdeps/unix/sysv/linux/nios2/Makefile
@@ -7,7 +7,3 @@ ifeq ($(subdir),misc)
 sysdep_headers += sys/cachectl.h
 sysdep_routines += cacheflush
 endif
-
-ifeq ($(subdir),nptl)
-libpthread-routines := $(filter-out pt-vfork,$(libpthread-routines))
-endif
diff --git a/sysdeps/unix/sysv/linux/nios2/pt-vfork.S b/sysdeps/unix/sysv/linux/nios2/pt-vfork.S
new file mode 100644
index 0000000000..147427a42d
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/nios2/pt-vfork.S
@@ -0,0 +1 @@
+# Nios2 does not require a stub for vfork in libpthread.
diff --git a/sysdeps/unix/sysv/linux/not-cancel.h b/sysdeps/unix/sysv/linux/not-cancel.h
index e6cdd144c2..0b5c955989 100644
--- a/sysdeps/unix/sysv/linux/not-cancel.h
+++ b/sysdeps/unix/sysv/linux/not-cancel.h
@@ -30,31 +30,24 @@
 
 /* Non cancellable open syscall.  */
 __typeof (open) __open_nocancel;
-libc_hidden_proto (__open_nocancel)
 
 /* Non cancellable open syscall (LFS version).  */
 __typeof (open64) __open64_nocancel;
-libc_hidden_proto (__open64_nocancel)
 
 /* Non cancellable openat syscall.  */
 __typeof (openat) __openat_nocancel;
-libc_hidden_proto (__openat_nocancel)
 
 /* Non cacellable openat syscall (LFS version).  */
 __typeof (openat64) __openat64_nocancel;
-libc_hidden_proto (__openat64_nocancel)
 
 /* Non cancellable read syscall.  */
 __typeof (__read) __read_nocancel;
-libc_hidden_proto (__read_nocancel)
 
 /* Uncancelable write.  */
 __typeof (__write) __write_nocancel;
-libc_hidden_proto (__write_nocancel)
 
 /* Uncancelable close.  */
 __typeof (__close) __close_nocancel;
-libc_hidden_proto (__close_nocancel)
 
 /* Non cancellable close syscall that does not also set errno in case of
    failure.  */
@@ -75,18 +68,28 @@ __writev_nocancel_nostatus (int fd, const struct iovec *iov, int iovcnt)
 
 /* Uncancelable waitpid.  */
 __typeof (waitpid) __waitpid_nocancel;
-libc_hidden_proto (__waitpid_nocancel)
 
 /* Uncancelable pause.  */
 __typeof (pause) __pause_nocancel;
-libc_hidden_proto (__pause_nocancel)
 
 /* Uncancelable nanosleep.  */
 __typeof (__nanosleep) __nanosleep_nocancel;
-hidden_proto (__nanosleep_nocancel)
 
 /* Uncancelable fcntl.  */
 __typeof (__fcntl) __fcntl_nocancel;
-libc_hidden_proto (__fcntl_nocancel)
+
+#if IS_IN (libc) || IS_IN (rtld)
+hidden_proto (__open_nocancel)
+hidden_proto (__open64_nocancel)
+hidden_proto (__openat_nocancel)
+hidden_proto (__openat64_nocancel)
+hidden_proto (__read_nocancel)
+hidden_proto (__write_nocancel)
+hidden_proto (__close_nocancel)
+hidden_proto (__waitpid_nocancel)
+hidden_proto (__pause_nocancel)
+hidden_proto (__nanosleep_nocancel)
+hidden_proto (__fcntl_nocancel)
+#endif
 
 #endif /* NOT_CANCEL_H  */
diff --git a/sysdeps/unix/sysv/linux/open.c b/sysdeps/unix/sysv/linux/open.c
index c189e285c9..7f12292b87 100644
--- a/sysdeps/unix/sysv/linux/open.c
+++ b/sysdeps/unix/sysv/linux/open.c
@@ -1,4 +1,5 @@
-/* Copyright (C) 2017-2018 Free Software Foundation, Inc.
+/* Linux open syscall implementation, non-LFS.
+   Copyright (C) 2017-2018 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011.
 
@@ -22,7 +23,6 @@
 #include <stdarg.h>
 
 #include <sysdep-cancel.h>
-#include <not-cancel.h>
 
 #ifndef __OFF_T_MATCHES_OFF64_T
 
@@ -48,25 +48,4 @@ libc_hidden_def (__libc_open)
 weak_alias (__libc_open, __open)
 libc_hidden_weak (__open)
 weak_alias (__libc_open, open)
-
-# if !IS_IN (rtld)
-int
-__open_nocancel (const char *file, int oflag, ...)
-{
-  int mode = 0;
-
-  if (__OPEN_NEEDS_MODE (oflag))
-    {
-      va_list arg;
-      va_start (arg, oflag);
-      mode = va_arg (arg, int);
-      va_end (arg);
-    }
-
-  return INLINE_SYSCALL_CALL (openat, AT_FDCWD, file, oflag, mode);
-}
-# else
-strong_alias (__libc_open, __open_nocancel)
-# endif
-libc_hidden_def (__open_nocancel)
 #endif
diff --git a/sysdeps/unix/sysv/linux/open64.c b/sysdeps/unix/sysv/linux/open64.c
index 4af5ee2466..55ef658800 100644
--- a/sysdeps/unix/sysv/linux/open64.c
+++ b/sysdeps/unix/sysv/linux/open64.c
@@ -1,4 +1,5 @@
-/* Copyright (C) 1991-2018 Free Software Foundation, Inc.
+/* Linux open syscall implementation, LFS.
+   Copyright (C) 1991-2018 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
@@ -21,7 +22,7 @@
 #include <stdarg.h>
 
 #include <sysdep-cancel.h>
-#include <not-cancel.h>
+
 
 #ifdef __OFF_T_MATCHES_OFF64_T
 # define EXTRA_OPEN_FLAGS 0
@@ -52,34 +53,9 @@ strong_alias (__libc_open64, __open64)
 libc_hidden_weak (__open64)
 weak_alias (__libc_open64, open64)
 
-# if !IS_IN (rtld)
-int
-__open64_nocancel (const char *file, int oflag, ...)
-{
-  int mode = 0;
-
-  if (__OPEN_NEEDS_MODE (oflag))
-    {
-      va_list arg;
-      va_start (arg, oflag);
-      mode = va_arg (arg, int);
-      va_end (arg);
-    }
-
-  return INLINE_SYSCALL_CALL (openat, AT_FDCWD, file, oflag | EXTRA_OPEN_FLAGS,
-			      mode);
-}
-#else
-strong_alias (__libc_open64, __open64_nocancel)
-#endif
-libc_hidden_def (__open64_nocancel)
-
 #ifdef __OFF_T_MATCHES_OFF64_T
 strong_alias (__libc_open64, __libc_open)
 strong_alias (__libc_open64, __open)
 libc_hidden_weak (__open)
 weak_alias (__libc_open64, open)
-
-strong_alias (__open64_nocancel, __open_nocancel)
-libc_hidden_weak (__open_nocancel)
 #endif
diff --git a/sysdeps/unix/sysv/linux/open64_nocancel.c b/sysdeps/unix/sysv/linux/open64_nocancel.c
new file mode 100644
index 0000000000..5d039eada6
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/open64_nocancel.c
@@ -0,0 +1,54 @@
+/* Linux open syscall implementation, LFS, non-cancellable.
+   Copyright (C) 2018 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 <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdarg.h>
+
+#include <not-cancel.h>
+
+#ifdef __OFF_T_MATCHES_OFF64_T
+# define EXTRA_OPEN_FLAGS 0
+#else
+# define EXTRA_OPEN_FLAGS O_LARGEFILE
+#endif
+
+int
+__open64_nocancel (const char *file, int oflag, ...)
+{
+  int mode = 0;
+
+  if (__OPEN_NEEDS_MODE (oflag))
+    {
+      va_list arg;
+      va_start (arg, oflag);
+      mode = va_arg (arg, int);
+      va_end (arg);
+    }
+
+  return INLINE_SYSCALL_CALL (openat, AT_FDCWD, file, oflag | EXTRA_OPEN_FLAGS,
+			      mode);
+}
+
+hidden_def (__open64_nocancel)
+
+#ifdef __OFF_T_MATCHES_OFF64_T
+strong_alias (__open64_nocancel, __open_nocancel)
+hidden_def (__open_nocancel)
+#endif
diff --git a/sysdeps/unix/sysv/linux/open_nocancel.c b/sysdeps/unix/sysv/linux/open_nocancel.c
new file mode 100644
index 0000000000..2ee3e527cb
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/open_nocancel.c
@@ -0,0 +1,46 @@
+/* Linux open syscall implementation, non-LFS, non-cancellable.
+   Copyright (C) 2018 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 <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdarg.h>
+
+#include <sysdep-cancel.h>
+#include <not-cancel.h>
+
+#ifndef __OFF_T_MATCHES_OFF64_T
+
+int
+__open_nocancel (const char *file, int oflag, ...)
+{
+  int mode = 0;
+
+  if (__OPEN_NEEDS_MODE (oflag))
+    {
+      va_list arg;
+      va_start (arg, oflag);
+      mode = va_arg (arg, int);
+      va_end (arg);
+    }
+
+  return INLINE_SYSCALL_CALL (openat, AT_FDCWD, file, oflag, mode);
+}
+hidden_def (__open_nocancel)
+
+#endif
diff --git a/sysdeps/unix/sysv/linux/openat.c b/sysdeps/unix/sysv/linux/openat.c
index 9601e617db..d0ad242271 100644
--- a/sysdeps/unix/sysv/linux/openat.c
+++ b/sysdeps/unix/sysv/linux/openat.c
@@ -1,4 +1,5 @@
-/* Copyright (C) 2005-2018 Free Software Foundation, Inc.
+/* Linux openat syscall implementation, non-LFS.
+   Copyright (C) 2005-2018 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
@@ -19,7 +20,6 @@
 #include <stdarg.h>
 
 #include <sysdep-cancel.h>
-#include <not-cancel.h>
 
 #ifndef __OFF_T_MATCHES_OFF64_T
 
@@ -43,24 +43,4 @@ __libc_openat (int fd, const char *file, int oflag, ...)
 weak_alias (__libc_openat, __openat)
 libc_hidden_weak (__openat)
 weak_alias (__libc_openat, openat)
-
-# if !IS_IN (rtld)
-int
-__openat_nocancel (int fd, const char *file, int oflag, ...)
-{
-  mode_t mode = 0;
-  if (__OPEN_NEEDS_MODE (oflag))
-    {
-      va_list arg;
-      va_start (arg, oflag);
-      mode = va_arg (arg, mode_t);
-      va_end (arg);
-    }
-
-  return INLINE_SYSCALL_CALL (openat, fd, file, oflag, mode);
-}
-# else
-strong_alias (__libc_openat, __openat_nocancel)
-# endif
-libc_hidden_weak (__openat_nocancel)
 #endif
diff --git a/sysdeps/unix/sysv/linux/openat64.c b/sysdeps/unix/sysv/linux/openat64.c
index 6f14711df3..536f4f5aff 100644
--- a/sysdeps/unix/sysv/linux/openat64.c
+++ b/sysdeps/unix/sysv/linux/openat64.c
@@ -1,4 +1,5 @@
-/* Copyright (C) 2007-2018 Free Software Foundation, Inc.
+/* Linux openat syscall implementation, LFS.
+   Copyright (C) 2007-2018 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
@@ -19,7 +20,6 @@
 #include <stdarg.h>
 
 #include <sysdep-cancel.h>
-#include <not-cancel.h>
 
 #ifdef __OFF_T_MATCHES_OFF64_T
 # define EXTRA_OPEN_FLAGS 0
@@ -49,31 +49,8 @@ strong_alias (__libc_openat64, __openat64)
 libc_hidden_weak (__openat64)
 weak_alias (__libc_openat64, openat64)
 
-#if !IS_IN (rtld)
-int
-__openat64_nocancel (int fd, const char *file, int oflag, ...)
-{
-  mode_t mode = 0;
-  if (__OPEN_NEEDS_MODE (oflag))
-    {
-      va_list arg;
-      va_start (arg, oflag);
-      mode = va_arg (arg, mode_t);
-      va_end (arg);
-    }
-
-  return INLINE_SYSCALL_CALL (openat, fd, file, oflag | EXTRA_OPEN_FLAGS,
-			      mode);
-}
-#else
-strong_alias (__libc_openat64, __openat64_nocancel)
-#endif
-libc_hidden_def (__openat64_nocancel)
-
 #ifdef __OFF_T_MATCHES_OFF64_T
 strong_alias (__libc_openat64, __openat)
 libc_hidden_weak (__openat)
 weak_alias (__libc_openat64, openat)
-
-strong_alias (__openat64_nocancel, __openat_nocancel)
 #endif
diff --git a/sysdeps/unix/sysv/linux/openat64_nocancel.c b/sysdeps/unix/sysv/linux/openat64_nocancel.c
new file mode 100644
index 0000000000..f3facc3b72
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/openat64_nocancel.c
@@ -0,0 +1,51 @@
+/* Linux openat syscall implementation, LFS, non-cancellable.
+   Copyright (C) 2018 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 <fcntl.h>
+#include <stdarg.h>
+
+#include <sysdep-cancel.h>
+#include <not-cancel.h>
+
+#ifdef __OFF_T_MATCHES_OFF64_T
+# define EXTRA_OPEN_FLAGS 0
+#else
+# define EXTRA_OPEN_FLAGS O_LARGEFILE
+#endif
+
+int
+__openat64_nocancel (int fd, const char *file, int oflag, ...)
+{
+  mode_t mode = 0;
+  if (__OPEN_NEEDS_MODE (oflag))
+    {
+      va_list arg;
+      va_start (arg, oflag);
+      mode = va_arg (arg, mode_t);
+      va_end (arg);
+    }
+
+  return INLINE_SYSCALL_CALL (openat, fd, file, oflag | EXTRA_OPEN_FLAGS,
+			      mode);
+}
+hidden_def (__openat64_nocancel)
+
+#ifdef __OFF_T_MATCHES_OFF64_T
+strong_alias (__openat64_nocancel, __openat_nocancel)
+hidden_def (__openat_nocancel)
+#endif
diff --git a/sysdeps/unix/sysv/linux/openat_nocancel.c b/sysdeps/unix/sysv/linux/openat_nocancel.c
new file mode 100644
index 0000000000..ac98238cda
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/openat_nocancel.c
@@ -0,0 +1,43 @@
+/* Linux openat syscall implementation, non-LFS, non-cancellable.
+   Copyright (C) 2018 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 <fcntl.h>
+#include <stdarg.h>
+
+#include <sysdep-cancel.h>
+#include <not-cancel.h>
+
+#ifndef __OFF_T_MATCHES_OFF64_T
+
+int
+__openat_nocancel (int fd, const char *file, int oflag, ...)
+{
+  mode_t mode = 0;
+  if (__OPEN_NEEDS_MODE (oflag))
+    {
+      va_list arg;
+      va_start (arg, oflag);
+      mode = va_arg (arg, mode_t);
+      va_end (arg);
+    }
+
+  return INLINE_SYSCALL_CALL (openat, fd, file, oflag, mode);
+}
+hidden_def (__openat_nocancel)
+
+#endif
diff --git a/sysdeps/unix/sysv/linux/pause.c b/sysdeps/unix/sysv/linux/pause.c
index 7c8d9f4861..7b90365b98 100644
--- a/sysdeps/unix/sysv/linux/pause.c
+++ b/sysdeps/unix/sysv/linux/pause.c
@@ -19,7 +19,6 @@
 #include <signal.h>
 #include <unistd.h>
 #include <sysdep-cancel.h>
-#include <not-cancel.h>
 
 /* Suspend the process until a signal arrives.
    This always returns -1 and sets errno to EINTR.  */
@@ -33,14 +32,3 @@ __libc_pause (void)
 #endif
 }
 weak_alias (__libc_pause, pause)
-
-int
-__pause_nocancel (void)
-{
-#ifdef __NR_pause
-  return INLINE_SYSCALL_CALL (pause);
-#else
-  return INLINE_SYSCALL_CALL (ppoll, NULL, 0, NULL, NULL);
-#endif
-}
-libc_hidden_def (__pause_nocancel)
diff --git a/sysdeps/unix/sysv/linux/pause_nocancel.c b/sysdeps/unix/sysv/linux/pause_nocancel.c
new file mode 100644
index 0000000000..322908c8ea
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/pause_nocancel.c
@@ -0,0 +1,33 @@
+/* Linux pause syscall implementation -- non-cancellable.
+   Copyright (C) 2018 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 <signal.h>
+#include <unistd.h>
+#include <sysdep-cancel.h>
+#include <not-cancel.h>
+
+int
+__pause_nocancel (void)
+{
+#ifdef __NR_pause
+  return INLINE_SYSCALL_CALL (pause);
+#else
+  return INLINE_SYSCALL_CALL (ppoll, NULL, 0, NULL, NULL);
+#endif
+}
+hidden_def (__pause_nocancel)
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h b/sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h
index 0fc179a9a1..0956cf04a7 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h
@@ -236,4 +236,13 @@
 # endif
 #endif
 
+/* In the PowerPC64 ABI, the unadorned F_GETLK* opcodes should be used
+   even by largefile64 code.  */
+#define FCNTL_ADJUST_CMD(__cmd)				\
+  ({ int cmd_ = (__cmd);				\
+     if (cmd_ >= F_GETLK64 && cmd_ <= F_SETLKW64)	\
+       cmd_ -= F_GETLK64 - F_GETLK;			\
+     cmd_; })
+
+
 #endif /* linux/powerpc/powerpc64/sysdep.h */
diff --git a/sysdeps/unix/sysv/linux/pthread_getname.c b/sysdeps/unix/sysv/linux/pthread_getname.c
index 358682f436..726218b4df 100644
--- a/sysdeps/unix/sysv/linux/pthread_getname.c
+++ b/sysdeps/unix/sysv/linux/pthread_getname.c
@@ -45,7 +45,7 @@ pthread_getname_np (pthread_t th, char *buf, size_t len)
   char fname[sizeof (FMT) + 8];
   sprintf (fname, FMT, (unsigned int) pd->tid);
 
-  int fd = __open_nocancel (fname, O_RDONLY);
+  int fd = __open64_nocancel (fname, O_RDONLY);
   if (fd == -1)
     return errno;
 
diff --git a/sysdeps/unix/sysv/linux/pthread_setname.c b/sysdeps/unix/sysv/linux/pthread_setname.c
index 5a8b500128..91b5273480 100644
--- a/sysdeps/unix/sysv/linux/pthread_setname.c
+++ b/sysdeps/unix/sysv/linux/pthread_setname.c
@@ -46,7 +46,7 @@ pthread_setname_np (pthread_t th, const char *name)
   char fname[sizeof (FMT) + 8];
   sprintf (fname, FMT, (unsigned int) pd->tid);
 
-  int fd = __open_nocancel (fname, O_RDWR);
+  int fd = __open64_nocancel (fname, O_RDWR);
   if (fd == -1)
     return errno;
 
diff --git a/sysdeps/unix/sysv/linux/read.c b/sysdeps/unix/sysv/linux/read.c
index 33ce38aaba..26d0bed404 100644
--- a/sysdeps/unix/sysv/linux/read.c
+++ b/sysdeps/unix/sysv/linux/read.c
@@ -18,7 +18,6 @@
 
 #include <unistd.h>
 #include <sysdep-cancel.h>
-#include <not-cancel.h>
 
 /* Read NBYTES into BUF from FD.  Return the number read or -1.  */
 ssize_t
@@ -32,14 +31,3 @@ libc_hidden_def (__read)
 weak_alias (__libc_read, __read)
 libc_hidden_def (read)
 weak_alias (__libc_read, read)
-
-#if !IS_IN (rtld)
-ssize_t
-__read_nocancel (int fd, void *buf, size_t nbytes)
-{
-  return INLINE_SYSCALL_CALL (read, fd, buf, nbytes);
-}
-#else
-strong_alias (__libc_read, __read_nocancel)
-#endif
-libc_hidden_def (__read_nocancel)
diff --git a/sysdeps/unix/sysv/linux/read_nocancel.c b/sysdeps/unix/sysv/linux/read_nocancel.c
new file mode 100644
index 0000000000..24699e3e21
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/read_nocancel.c
@@ -0,0 +1,28 @@
+/* Linux read syscall implementation -- non-cancellable.
+   Copyright (C) 2018 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 <unistd.h>
+#include <sysdep-cancel.h>
+#include <not-cancel.h>
+
+ssize_t
+__read_nocancel (int fd, void *buf, size_t nbytes)
+{
+  return INLINE_SYSCALL_CALL (read, fd, buf, nbytes);
+}
+hidden_def (__read_nocancel)
diff --git a/sysdeps/unix/sysv/linux/waitpid.c b/sysdeps/unix/sysv/linux/waitpid.c
index d1d30fd431..8cf00e4efd 100644
--- a/sysdeps/unix/sysv/linux/waitpid.c
+++ b/sysdeps/unix/sysv/linux/waitpid.c
@@ -1,4 +1,5 @@
-/* Copyright (C) 1991-2018 Free Software Foundation, Inc.
+/* Linux waitpid syscall implementation.
+   Copyright (C) 1991-2018 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
@@ -19,7 +20,6 @@
 #include <sysdep-cancel.h>
 #include <stdlib.h>
 #include <sys/wait.h>
-#include <not-cancel.h>
 
 __pid_t
 __waitpid (__pid_t pid, int *stat_loc, int options)
@@ -32,14 +32,3 @@ __waitpid (__pid_t pid, int *stat_loc, int options)
 }
 libc_hidden_def (__waitpid)
 weak_alias (__waitpid, waitpid)
-
-__pid_t
-__waitpid_nocancel (__pid_t pid, int *stat_loc, int options)
-{
-#ifdef __NR_waitpid
-  return INLINE_SYSCALL_CALL (waitpid, pid, stat_loc, options);
-#else
-  return INLINE_SYSCALL_CALL (wait4, pid, stat_loc, options, NULL);
-#endif
-}
-libc_hidden_def (__waitpid_nocancel)
diff --git a/sysdeps/unix/sysv/linux/waitpid_nocancel.c b/sysdeps/unix/sysv/linux/waitpid_nocancel.c
new file mode 100644
index 0000000000..ff1ef3d241
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/waitpid_nocancel.c
@@ -0,0 +1,34 @@
+/* Linux waitpid syscall implementation -- non-cancellable.
+   Copyright (C) 2018 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 <sysdep-cancel.h>
+#include <stdlib.h>
+#include <sys/wait.h>
+#include <not-cancel.h>
+
+__pid_t
+__waitpid_nocancel (__pid_t pid, int *stat_loc, int options)
+{
+#ifdef __NR_waitpid
+  return INLINE_SYSCALL_CALL (waitpid, pid, stat_loc, options);
+#else
+  return INLINE_SYSCALL_CALL (wait4, pid, stat_loc, options, NULL);
+#endif
+}
+libc_hidden_def (__waitpid_nocancel)
diff --git a/sysdeps/unix/sysv/linux/write.c b/sysdeps/unix/sysv/linux/write.c
index c96dc6f397..558639d471 100644
--- a/sysdeps/unix/sysv/linux/write.c
+++ b/sysdeps/unix/sysv/linux/write.c
@@ -18,7 +18,6 @@
 
 #include <unistd.h>
 #include <sysdep-cancel.h>
-#include <not-cancel.h>
 
 /* Write NBYTES of BUF to FD.  Return the number written, or -1.  */
 ssize_t
@@ -32,14 +31,3 @@ weak_alias (__libc_write, __write)
 libc_hidden_weak (__write)
 weak_alias (__libc_write, write)
 libc_hidden_weak (write)
-
-#if !IS_IN (rtld)
-ssize_t
-__write_nocancel (int fd, const void *buf, size_t nbytes)
-{
-  return INLINE_SYSCALL_CALL (write, fd, buf, nbytes);
-}
-#else
-strong_alias (__libc_write, __write_nocancel)
-#endif
-libc_hidden_def (__write_nocancel)
diff --git a/sysdeps/unix/sysv/linux/write_nocancel.c b/sysdeps/unix/sysv/linux/write_nocancel.c
new file mode 100644
index 0000000000..6fe1ea2aaa
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/write_nocancel.c
@@ -0,0 +1,28 @@
+/* Linux write syscall implementation -- non-cancellable.
+   Copyright (C) 2018 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 <unistd.h>
+#include <sysdep-cancel.h>
+#include <not-cancel.h>
+
+ssize_t
+__write_nocancel (int fd, const void *buf, size_t nbytes)
+{
+  return INLINE_SYSCALL_CALL (write, fd, buf, nbytes);
+}
+hidden_def (__write_nocancel)