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-rw-r--r--NEWS11
-rw-r--r--manual/threads.texi81
-rw-r--r--sysdeps/nptl/dl-tls_init_tp.c23
-rw-r--r--sysdeps/unix/sysv/linux/Makefile3
-rw-r--r--sysdeps/unix/sysv/linux/Versions5
-rw-r--r--sysdeps/unix/sysv/linux/aarch64/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/alpha/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/arc/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/arm/be/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/arm/le/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/csky/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/hppa/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/i386/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/ia64/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/m68k/coldfire/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/m68k/m680x0/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/microblaze/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/mips/mips32/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/mips/mips64/n32/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/mips/mips64/n64/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/nios2/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/powerpc/powerpc32/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/powerpc/powerpc64/be/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/powerpc/powerpc64/le/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/riscv/rv32/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/riscv/rv64/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/rseq-internal.h8
-rw-r--r--sysdeps/unix/sysv/linux/s390/s390-32/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/s390/s390-64/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/sh/be/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/sh/le/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/sparc/sparc32/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/sparc/sparc64/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/sys/rseq.h10
-rw-r--r--sysdeps/unix/sysv/linux/tst-rseq-disable.c6
-rw-r--r--sysdeps/unix/sysv/linux/tst-rseq.c8
-rw-r--r--sysdeps/unix/sysv/linux/x86_64/64/ld.abilist3
-rw-r--r--sysdeps/unix/sysv/linux/x86_64/x32/ld.abilist3
38 files changed, 237 insertions, 5 deletions
diff --git a/NEWS b/NEWS
index 1398cf2e87..8744a92532 100644
--- a/NEWS
+++ b/NEWS
@@ -68,6 +68,17 @@ Major new features:
   to be used by compilers for optimizing usage of 'memcmp' when its
   return value is only used for its boolean status.
 
+* Support for automatically registering threads with the Linux rseq
+  system call has been added.  This system call is implemented starting
+  from Linux 4.18.  The Restartable Sequences ABI accelerates user-space
+  operations on per-cpu data.  It allows user-space to perform updates
+  on per-cpu data without requiring heavy-weight atomic operations.
+  Automatically registering threads allows all libraries, including
+  libc, to make immediate use of the rseq support by using the
+  documented ABI, via the __rseq_flags, __rseq_offset, and __rseq_size
+  variables.  The GNU C Library manual has details on integration of
+  Restartable Sequences.
+
 Deprecated and removed features, and other changes affecting compatibility:
 
 * The r_version update in the debugger interface makes the glibc binary
diff --git a/manual/threads.texi b/manual/threads.texi
index 06b6b277a1..ab44a92ca0 100644
--- a/manual/threads.texi
+++ b/manual/threads.texi
@@ -629,6 +629,8 @@ the standard.
 * Waiting with Explicit Clocks::          Functions for waiting with an
                                           explicit clock specification.
 * Single-Threaded::                       Detecting single-threaded execution.
+* Restartable Sequences::                 Linux-specific restartable sequences
+                                          integration.
 @end menu
 
 @node Default Thread Attributes
@@ -958,6 +960,85 @@ application-created thread because future versions of @theglibc{} may
 create background threads after the first thread has been created, and
 the application has no way of knowning that these threads are present.
 
+@node Restartable Sequences
+@subsubsection Restartable Sequences
+
+This section describes restartable sequences integration for
+@theglibc{}.  This functionality is only available on Linux.
+
+@deftp {Data Type} {struct rseq}
+@standards{Linux, sys/rseq.h}
+The type of the restartable sequences area.  Future versions
+of Linux may add additional fields to the end of this structure.
+
+
+Users need to obtain the address of the restartable sequences area using
+the thread pointer and the @code{__rseq_offset} variable, described
+below.
+
+One use of the restartable sequences area is to read the current CPU
+number from its @code{cpu_id} field, as an inline version of
+@code{sched_getcpu}.  @Theglibc{} sets the @code{cpu_id} field to
+@code{RSEQ_CPU_ID_REGISTRATION_FAILED} if registration failed or was
+explicitly disabled.
+
+Furthermore, users can store the address of a @code{struct rseq_cs}
+object into the @code{rseq_cs} field of @code{struct rseq}, thus
+informing the kernel that the thread enters a restartable sequence
+critical section.  This pointer and the code areas it itself points to
+must not be left pointing to memory areas which are freed or re-used.
+Several approaches can guarantee this.  If the application or library
+can guarantee that the memory used to hold the @code{struct rseq_cs} and
+the code areas it refers to are never freed or re-used, no special
+action must be taken.  Else, before that memory is re-used of freed, the
+application is responsible for setting the @code{rseq_cs} field to
+@code{NULL} in each thread's restartable sequence area to guarantee that
+it does not leak dangling references.  Because the application does not
+typically have knowledge of libraries' use of restartable sequences, it
+is recommended that libraries using restartable sequences which may end
+up freeing or re-using their memory set the @code{rseq_cs} field to
+@code{NULL} before returning from library functions which use
+restartable sequences.
+
+The manual for the @code{rseq} system call can be found
+at @uref{https://git.kernel.org/pub/scm/libs/librseq/librseq.git/tree/doc/man/rseq.2}.
+@end deftp
+
+@deftypevar {int} __rseq_offset
+@standards{Linux, sys/rseq.h}
+This variable contains the offset between the thread pointer (as defined
+by @code{__builtin_thread_pointer} or the thread pointer register for
+the architecture) and the restartable sequences area.  This value is the
+same for all threads in the process.  If the restartable sequences area
+is located at a lower address than the location to which the thread
+pointer points, the value is negative.
+@end deftypevar
+
+@deftypevar {unsigned int} __rseq_size
+@standards{Linux, sys/rseq.h}
+This variable is either zero (if restartable sequence registration
+failed or has been disabled) or the size of the restartable sequence
+registration.  This can be different from the size of @code{struct rseq}
+if the kernel has extended the size of the registration.  If
+registration is successful, @code{__rseq_size} is at least 32 (the
+initial size of @code{struct rseq}).
+@end deftypevar
+
+@deftypevar {unsigned int} __rseq_flags
+@standards{Linux, sys/rseq.h}
+The flags used during restartable sequence registration with the kernel.
+Currently zero.
+@end deftypevar
+
+@deftypevr Macro int RSEQ_SIG
+@standards{Linux, sys/rseq.h}
+Each supported architecture provides a @code{RSEQ_SIG} macro in
+@file{sys/rseq.h} which contains a signature.  That signature is
+expected to be present in the code before each restartable sequences
+abort handler.  Failure to provide the expected signature may terminate
+the process with a segmentation fault.
+@end deftypevr
+
 @c FIXME these are undocumented:
 @c pthread_atfork
 @c pthread_attr_destroy
diff --git a/sysdeps/nptl/dl-tls_init_tp.c b/sysdeps/nptl/dl-tls_init_tp.c
index b39dfbff2c..4a73927f80 100644
--- a/sysdeps/nptl/dl-tls_init_tp.c
+++ b/sysdeps/nptl/dl-tls_init_tp.c
@@ -22,6 +22,7 @@
 #include <pthreadP.h>
 #include <tls.h>
 #include <rseq-internal.h>
+#include <thread_pointer.h>
 
 #define TUNABLE_NAMESPACE pthread
 #include <dl-tunables.h>
@@ -43,6 +44,10 @@ rtld_mutex_dummy (pthread_mutex_t *lock)
 }
 #endif
 
+const unsigned int __rseq_flags;
+const unsigned int __rseq_size attribute_relro;
+const int __rseq_offset attribute_relro;
+
 void
 __tls_pre_init_tp (void)
 {
@@ -100,7 +105,23 @@ __tls_init_tp (void)
 #if HAVE_TUNABLES
     do_rseq = TUNABLE_GET (rseq, int, NULL);
 #endif
-    rseq_register_current_thread (pd, do_rseq);
+    if (rseq_register_current_thread (pd, do_rseq))
+      {
+        /* We need a writable view of the variables.  They are in
+           .data.relro and are not yet write-protected.  */
+        extern unsigned int size __asm__ ("__rseq_size");
+        size = sizeof (pd->rseq_area);
+      }
+
+#ifdef RSEQ_SIG
+    /* This should be a compile-time constant, but the current
+       infrastructure makes it difficult to determine its value.  Not
+       all targets support __thread_pointer, so set __rseq_offset only
+       if thre rseq registration may have happened because RSEQ_SIG is
+       defined.  */
+    extern int offset __asm__ ("__rseq_offset");
+    offset = (char *) &pd->rseq_area - (char *) __thread_pointer ();
+#endif
   }
 
   /* Set initial thread's stack block from 0 up to __libc_stack_end.
diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile
index 62a796f214..61acc1987d 100644
--- a/sysdeps/unix/sysv/linux/Makefile
+++ b/sysdeps/unix/sysv/linux/Makefile
@@ -112,7 +112,8 @@ sysdep_headers += sys/mount.h sys/acct.h \
 		  bits/types/struct_semid64_ds_helper.h \
 		  bits/types/struct_shmid64_ds.h \
 		  bits/types/struct_shmid64_ds_helper.h \
-		  bits/pthread_stack_min.h bits/pthread_stack_min-dynamic.h
+		  bits/pthread_stack_min.h bits/pthread_stack_min-dynamic.h \
+		  sys/rseq.h bits/rseq.h
 
 tests += tst-clone tst-clone2 tst-clone3 tst-fanotify tst-personality \
 	 tst-quota tst-sync_file_range tst-sysconf-iov_max tst-ttyname \
diff --git a/sysdeps/unix/sysv/linux/Versions b/sysdeps/unix/sysv/linux/Versions
index 26452f3f17..3f8809a158 100644
--- a/sysdeps/unix/sysv/linux/Versions
+++ b/sysdeps/unix/sysv/linux/Versions
@@ -316,6 +316,11 @@ librt {
 }
 
 ld {
+  GLIBC_2.35 {
+    __rseq_flags;
+    __rseq_offset;
+    __rseq_size;
+  }
   GLIBC_PRIVATE {
     __nptl_change_stack_perm;
   }
diff --git a/sysdeps/unix/sysv/linux/aarch64/ld.abilist b/sysdeps/unix/sysv/linux/aarch64/ld.abilist
index 80b2fe6725..717a35f242 100644
--- a/sysdeps/unix/sysv/linux/aarch64/ld.abilist
+++ b/sysdeps/unix/sysv/linux/aarch64/ld.abilist
@@ -3,3 +3,6 @@ GLIBC_2.17 __stack_chk_guard D 0x8
 GLIBC_2.17 __tls_get_addr F
 GLIBC_2.17 _dl_mcount F
 GLIBC_2.17 _r_debug D 0x28
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/alpha/ld.abilist b/sysdeps/unix/sysv/linux/alpha/ld.abilist
index 98a03f611f..76911bd7f8 100644
--- a/sysdeps/unix/sysv/linux/alpha/ld.abilist
+++ b/sysdeps/unix/sysv/linux/alpha/ld.abilist
@@ -2,4 +2,7 @@ GLIBC_2.0 _r_debug D 0x28
 GLIBC_2.1 __libc_stack_end D 0x8
 GLIBC_2.1 _dl_mcount F
 GLIBC_2.3 __tls_get_addr F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
 GLIBC_2.4 __stack_chk_guard D 0x8
diff --git a/sysdeps/unix/sysv/linux/arc/ld.abilist b/sysdeps/unix/sysv/linux/arc/ld.abilist
index 048f17c848..71c67f9803 100644
--- a/sysdeps/unix/sysv/linux/arc/ld.abilist
+++ b/sysdeps/unix/sysv/linux/arc/ld.abilist
@@ -3,3 +3,6 @@ GLIBC_2.32 __stack_chk_guard D 0x4
 GLIBC_2.32 __tls_get_addr F
 GLIBC_2.32 _dl_mcount F
 GLIBC_2.32 _r_debug D 0x14
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/arm/be/ld.abilist b/sysdeps/unix/sysv/linux/arm/be/ld.abilist
index cc8825c3bc..3859433b21 100644
--- a/sysdeps/unix/sysv/linux/arm/be/ld.abilist
+++ b/sysdeps/unix/sysv/linux/arm/be/ld.abilist
@@ -1,3 +1,6 @@
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
 GLIBC_2.4 __libc_stack_end D 0x4
 GLIBC_2.4 __stack_chk_guard D 0x4
 GLIBC_2.4 __tls_get_addr F
diff --git a/sysdeps/unix/sysv/linux/arm/le/ld.abilist b/sysdeps/unix/sysv/linux/arm/le/ld.abilist
index cc8825c3bc..3859433b21 100644
--- a/sysdeps/unix/sysv/linux/arm/le/ld.abilist
+++ b/sysdeps/unix/sysv/linux/arm/le/ld.abilist
@@ -1,3 +1,6 @@
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
 GLIBC_2.4 __libc_stack_end D 0x4
 GLIBC_2.4 __stack_chk_guard D 0x4
 GLIBC_2.4 __tls_get_addr F
diff --git a/sysdeps/unix/sysv/linux/csky/ld.abilist b/sysdeps/unix/sysv/linux/csky/ld.abilist
index 564ac09737..6bfc582b73 100644
--- a/sysdeps/unix/sysv/linux/csky/ld.abilist
+++ b/sysdeps/unix/sysv/linux/csky/ld.abilist
@@ -3,3 +3,6 @@ GLIBC_2.29 __stack_chk_guard D 0x4
 GLIBC_2.29 __tls_get_addr F
 GLIBC_2.29 _dl_mcount F
 GLIBC_2.29 _r_debug D 0x14
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/hppa/ld.abilist b/sysdeps/unix/sysv/linux/hppa/ld.abilist
index d155a59843..efccd6a023 100644
--- a/sysdeps/unix/sysv/linux/hppa/ld.abilist
+++ b/sysdeps/unix/sysv/linux/hppa/ld.abilist
@@ -2,4 +2,7 @@ GLIBC_2.2 __libc_stack_end D 0x4
 GLIBC_2.2 _dl_mcount F
 GLIBC_2.2 _r_debug D 0x14
 GLIBC_2.3 __tls_get_addr F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
 GLIBC_2.4 __stack_chk_guard D 0x4
diff --git a/sysdeps/unix/sysv/linux/i386/ld.abilist b/sysdeps/unix/sysv/linux/i386/ld.abilist
index 0478e22071..1eb94ae75f 100644
--- a/sysdeps/unix/sysv/linux/i386/ld.abilist
+++ b/sysdeps/unix/sysv/linux/i386/ld.abilist
@@ -3,3 +3,6 @@ GLIBC_2.1 __libc_stack_end D 0x4
 GLIBC_2.1 _dl_mcount F
 GLIBC_2.3 ___tls_get_addr F
 GLIBC_2.3 __tls_get_addr F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/ia64/ld.abilist b/sysdeps/unix/sysv/linux/ia64/ld.abilist
index 33f91199bf..2cc68bcf7b 100644
--- a/sysdeps/unix/sysv/linux/ia64/ld.abilist
+++ b/sysdeps/unix/sysv/linux/ia64/ld.abilist
@@ -2,3 +2,6 @@ GLIBC_2.2 __libc_stack_end D 0x8
 GLIBC_2.2 _dl_mcount F
 GLIBC_2.2 _r_debug D 0x28
 GLIBC_2.3 __tls_get_addr F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/ld.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/ld.abilist
index cc8825c3bc..3859433b21 100644
--- a/sysdeps/unix/sysv/linux/m68k/coldfire/ld.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/coldfire/ld.abilist
@@ -1,3 +1,6 @@
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
 GLIBC_2.4 __libc_stack_end D 0x4
 GLIBC_2.4 __stack_chk_guard D 0x4
 GLIBC_2.4 __tls_get_addr F
diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/ld.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/ld.abilist
index 3ba474c27f..e62b2742af 100644
--- a/sysdeps/unix/sysv/linux/m68k/m680x0/ld.abilist
+++ b/sysdeps/unix/sysv/linux/m68k/m680x0/ld.abilist
@@ -2,4 +2,7 @@ GLIBC_2.0 _r_debug D 0x14
 GLIBC_2.1 __libc_stack_end D 0x4
 GLIBC_2.1 _dl_mcount F
 GLIBC_2.3 __tls_get_addr F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
 GLIBC_2.4 __stack_chk_guard D 0x4
diff --git a/sysdeps/unix/sysv/linux/microblaze/ld.abilist b/sysdeps/unix/sysv/linux/microblaze/ld.abilist
index a4933c3541..5d63d74e8f 100644
--- a/sysdeps/unix/sysv/linux/microblaze/ld.abilist
+++ b/sysdeps/unix/sysv/linux/microblaze/ld.abilist
@@ -3,3 +3,6 @@ GLIBC_2.18 __stack_chk_guard D 0x4
 GLIBC_2.18 __tls_get_addr F
 GLIBC_2.18 _dl_mcount F
 GLIBC_2.18 _r_debug D 0x14
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/mips/mips32/ld.abilist b/sysdeps/unix/sysv/linux/mips/mips32/ld.abilist
index be09641a48..53ca22de2f 100644
--- a/sysdeps/unix/sysv/linux/mips/mips32/ld.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips32/ld.abilist
@@ -2,4 +2,7 @@ GLIBC_2.0 _r_debug D 0x14
 GLIBC_2.2 __libc_stack_end D 0x4
 GLIBC_2.2 _dl_mcount F
 GLIBC_2.3 __tls_get_addr F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
 GLIBC_2.4 __stack_chk_guard D 0x4
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/ld.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n32/ld.abilist
index be09641a48..53ca22de2f 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n32/ld.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/ld.abilist
@@ -2,4 +2,7 @@ GLIBC_2.0 _r_debug D 0x14
 GLIBC_2.2 __libc_stack_end D 0x4
 GLIBC_2.2 _dl_mcount F
 GLIBC_2.3 __tls_get_addr F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
 GLIBC_2.4 __stack_chk_guard D 0x4
diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/ld.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n64/ld.abilist
index 1ea36e13f2..d1cdd68333 100644
--- a/sysdeps/unix/sysv/linux/mips/mips64/n64/ld.abilist
+++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/ld.abilist
@@ -2,4 +2,7 @@ GLIBC_2.0 _r_debug D 0x28
 GLIBC_2.2 __libc_stack_end D 0x8
 GLIBC_2.2 _dl_mcount F
 GLIBC_2.3 __tls_get_addr F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
 GLIBC_2.4 __stack_chk_guard D 0x8
diff --git a/sysdeps/unix/sysv/linux/nios2/ld.abilist b/sysdeps/unix/sysv/linux/nios2/ld.abilist
index 52178802dd..bcbba1823e 100644
--- a/sysdeps/unix/sysv/linux/nios2/ld.abilist
+++ b/sysdeps/unix/sysv/linux/nios2/ld.abilist
@@ -3,3 +3,6 @@ GLIBC_2.21 __stack_chk_guard D 0x4
 GLIBC_2.21 __tls_get_addr F
 GLIBC_2.21 _dl_mcount F
 GLIBC_2.21 _r_debug D 0x14
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/ld.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/ld.abilist
index 4bbfba7a61..0d033cb8bd 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/ld.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/ld.abilist
@@ -4,3 +4,6 @@ GLIBC_2.1 _dl_mcount F
 GLIBC_2.22 __tls_get_addr_opt F
 GLIBC_2.23 __parse_hwcap_and_convert_at_platform F
 GLIBC_2.3 __tls_get_addr F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/ld.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/ld.abilist
index 283fb4510b..9c627b1ddf 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/ld.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/ld.abilist
@@ -4,3 +4,6 @@ GLIBC_2.3 __libc_stack_end D 0x8
 GLIBC_2.3 __tls_get_addr F
 GLIBC_2.3 _dl_mcount F
 GLIBC_2.3 _r_debug D 0x28
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/ld.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/ld.abilist
index b1f313c7cd..3a748c2817 100644
--- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/ld.abilist
+++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/ld.abilist
@@ -4,3 +4,6 @@ GLIBC_2.17 _dl_mcount F
 GLIBC_2.17 _r_debug D 0x28
 GLIBC_2.22 __tls_get_addr_opt F
 GLIBC_2.23 __parse_hwcap_and_convert_at_platform F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/riscv/rv32/ld.abilist b/sysdeps/unix/sysv/linux/riscv/rv32/ld.abilist
index 94ca64c43d..4c67ea18d6 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv32/ld.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv32/ld.abilist
@@ -3,3 +3,6 @@ GLIBC_2.33 __stack_chk_guard D 0x4
 GLIBC_2.33 __tls_get_addr F
 GLIBC_2.33 _dl_mcount F
 GLIBC_2.33 _r_debug D 0x14
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/riscv/rv64/ld.abilist b/sysdeps/unix/sysv/linux/riscv/rv64/ld.abilist
index 845f356c3c..09596f09e2 100644
--- a/sysdeps/unix/sysv/linux/riscv/rv64/ld.abilist
+++ b/sysdeps/unix/sysv/linux/riscv/rv64/ld.abilist
@@ -3,3 +3,6 @@ GLIBC_2.27 __stack_chk_guard D 0x8
 GLIBC_2.27 __tls_get_addr F
 GLIBC_2.27 _dl_mcount F
 GLIBC_2.27 _r_debug D 0x28
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/rseq-internal.h b/sysdeps/unix/sysv/linux/rseq-internal.h
index 15bc7ffd6e..9e8f99fd51 100644
--- a/sysdeps/unix/sysv/linux/rseq-internal.h
+++ b/sysdeps/unix/sysv/linux/rseq-internal.h
@@ -26,7 +26,7 @@
 #include <sys/rseq.h>
 
 #ifdef RSEQ_SIG
-static inline void
+static inline bool
 rseq_register_current_thread (struct pthread *self, bool do_rseq)
 {
   if (do_rseq)
@@ -35,15 +35,17 @@ rseq_register_current_thread (struct pthread *self, bool do_rseq)
                                        sizeof (self->rseq_area),
                                        0, RSEQ_SIG);
       if (!INTERNAL_SYSCALL_ERROR_P (ret))
-        return;
+        return true;
     }
   THREAD_SETMEM (self, rseq_area.cpu_id, RSEQ_CPU_ID_REGISTRATION_FAILED);
+  return false;
 }
 #else /* RSEQ_SIG */
-static inline void
+static inline bool
 rseq_register_current_thread (struct pthread *self, bool do_rseq)
 {
   THREAD_SETMEM (self, rseq_area.cpu_id, RSEQ_CPU_ID_REGISTRATION_FAILED);
+  return false;
 }
 #endif /* RSEQ_SIG */
 
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/ld.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/ld.abilist
index b56f005beb..2c47004bae 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-32/ld.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/ld.abilist
@@ -2,3 +2,6 @@ GLIBC_2.0 _r_debug D 0x14
 GLIBC_2.1 __libc_stack_end D 0x4
 GLIBC_2.1 _dl_mcount F
 GLIBC_2.3 __tls_get_offset F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/ld.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/ld.abilist
index 6f788a086d..385a73a257 100644
--- a/sysdeps/unix/sysv/linux/s390/s390-64/ld.abilist
+++ b/sysdeps/unix/sysv/linux/s390/s390-64/ld.abilist
@@ -2,3 +2,6 @@ GLIBC_2.2 __libc_stack_end D 0x8
 GLIBC_2.2 _dl_mcount F
 GLIBC_2.2 _r_debug D 0x28
 GLIBC_2.3 __tls_get_offset F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/sh/be/ld.abilist b/sysdeps/unix/sysv/linux/sh/be/ld.abilist
index d155a59843..efccd6a023 100644
--- a/sysdeps/unix/sysv/linux/sh/be/ld.abilist
+++ b/sysdeps/unix/sysv/linux/sh/be/ld.abilist
@@ -2,4 +2,7 @@ GLIBC_2.2 __libc_stack_end D 0x4
 GLIBC_2.2 _dl_mcount F
 GLIBC_2.2 _r_debug D 0x14
 GLIBC_2.3 __tls_get_addr F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
 GLIBC_2.4 __stack_chk_guard D 0x4
diff --git a/sysdeps/unix/sysv/linux/sh/le/ld.abilist b/sysdeps/unix/sysv/linux/sh/le/ld.abilist
index d155a59843..efccd6a023 100644
--- a/sysdeps/unix/sysv/linux/sh/le/ld.abilist
+++ b/sysdeps/unix/sysv/linux/sh/le/ld.abilist
@@ -2,4 +2,7 @@ GLIBC_2.2 __libc_stack_end D 0x4
 GLIBC_2.2 _dl_mcount F
 GLIBC_2.2 _r_debug D 0x14
 GLIBC_2.3 __tls_get_addr F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
 GLIBC_2.4 __stack_chk_guard D 0x4
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/ld.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/ld.abilist
index 0c6610e3c2..8fb5ff3ef3 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc32/ld.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc32/ld.abilist
@@ -2,3 +2,6 @@ GLIBC_2.0 _r_debug D 0x14
 GLIBC_2.1 __libc_stack_end D 0x4
 GLIBC_2.1 _dl_mcount F
 GLIBC_2.3 __tls_get_addr F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/ld.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/ld.abilist
index 33f91199bf..2cc68bcf7b 100644
--- a/sysdeps/unix/sysv/linux/sparc/sparc64/ld.abilist
+++ b/sysdeps/unix/sysv/linux/sparc/sparc64/ld.abilist
@@ -2,3 +2,6 @@ GLIBC_2.2 __libc_stack_end D 0x8
 GLIBC_2.2 _dl_mcount F
 GLIBC_2.2 _r_debug D 0x28
 GLIBC_2.3 __tls_get_addr F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/sys/rseq.h b/sysdeps/unix/sysv/linux/sys/rseq.h
index c8edff50d4..1215b5d086 100644
--- a/sysdeps/unix/sysv/linux/sys/rseq.h
+++ b/sysdeps/unix/sysv/linux/sys/rseq.h
@@ -171,4 +171,14 @@ struct rseq
 
 #endif /* __GLIBC_HAVE_KERNEL_RSEQ */
 
+/* Offset from the thread pointer to the rseq area.  */
+extern const int __rseq_offset;
+
+/* Size of the registered rseq area.  0 if the registration was
+   unsuccessful.  */
+extern const unsigned int __rseq_size;
+
+/* Flags used during rseq registration.  */
+extern const unsigned int __rseq_flags;
+
 #endif /* sys/rseq.h */
diff --git a/sysdeps/unix/sysv/linux/tst-rseq-disable.c b/sysdeps/unix/sysv/linux/tst-rseq-disable.c
index 000e351872..6d73f77e96 100644
--- a/sysdeps/unix/sysv/linux/tst-rseq-disable.c
+++ b/sysdeps/unix/sysv/linux/tst-rseq-disable.c
@@ -21,6 +21,7 @@
 #include <support/namespace.h>
 #include <support/xthread.h>
 #include <sysdep.h>
+#include <thread_pointer.h>
 #include <unistd.h>
 
 #ifdef RSEQ_SIG
@@ -30,6 +31,11 @@ static void
 check_rseq_disabled (void)
 {
   struct pthread *pd = THREAD_SELF;
+
+  TEST_COMPARE (__rseq_flags, 0);
+  TEST_VERIFY ((char *) __thread_pointer () + __rseq_offset
+               == (char *) &pd->rseq_area);
+  TEST_COMPARE (__rseq_size, 0);
   TEST_COMPARE ((int) pd->rseq_area.cpu_id, RSEQ_CPU_ID_REGISTRATION_FAILED);
 
   int ret = syscall (__NR_rseq, &pd->rseq_area, sizeof (pd->rseq_area),
diff --git a/sysdeps/unix/sysv/linux/tst-rseq.c b/sysdeps/unix/sysv/linux/tst-rseq.c
index 926376b6a5..572c11166f 100644
--- a/sysdeps/unix/sysv/linux/tst-rseq.c
+++ b/sysdeps/unix/sysv/linux/tst-rseq.c
@@ -29,12 +29,20 @@
 # include <stdlib.h>
 # include <string.h>
 # include <syscall.h>
+# include <thread_pointer.h>
+# include <tls.h>
 # include "tst-rseq.h"
 
 static void
 do_rseq_main_test (void)
 {
+  struct pthread *pd = THREAD_SELF;
+
   TEST_VERIFY_EXIT (rseq_thread_registered ());
+  TEST_COMPARE (__rseq_flags, 0);
+  TEST_VERIFY ((char *) __thread_pointer () + __rseq_offset
+               == (char *) &pd->rseq_area);
+  TEST_COMPARE (__rseq_size, sizeof (pd->rseq_area));
 }
 
 static void
diff --git a/sysdeps/unix/sysv/linux/x86_64/64/ld.abilist b/sysdeps/unix/sysv/linux/x86_64/64/ld.abilist
index d3cdf7611e..49a8f31c93 100644
--- a/sysdeps/unix/sysv/linux/x86_64/64/ld.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/64/ld.abilist
@@ -2,3 +2,6 @@ GLIBC_2.2.5 __libc_stack_end D 0x8
 GLIBC_2.2.5 _dl_mcount F
 GLIBC_2.2.5 _r_debug D 0x28
 GLIBC_2.3 __tls_get_addr F
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4
diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/ld.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/ld.abilist
index c70bccf782..ce68cc6304 100644
--- a/sysdeps/unix/sysv/linux/x86_64/x32/ld.abilist
+++ b/sysdeps/unix/sysv/linux/x86_64/x32/ld.abilist
@@ -2,3 +2,6 @@ GLIBC_2.16 __libc_stack_end D 0x4
 GLIBC_2.16 __tls_get_addr F
 GLIBC_2.16 _dl_mcount F
 GLIBC_2.16 _r_debug D 0x14
+GLIBC_2.35 __rseq_flags D 0x4
+GLIBC_2.35 __rseq_offset D 0x4
+GLIBC_2.35 __rseq_size D 0x4