[PATCH 00/18] More y2038 fixes

Adhemerval Zanella adhemerval.zanella@linaro.org
Thu Jun 17 11:50:46 GMT 2021


Hi Carlos and Lukasz,

This patchset adds more y2038 fixes that I would like to push for 2.34.
The first two patches enable more internal y2038 usage on glibc and
also for the installed programs.  Making glibc the first consumer of
these newer interfaces should improve coverage.

The next 6 patches removes an optimization I added on some specific
syscall, where a global variable it atomically set once glibc detects
that kernel supports 64-bit time.  The problem with this approach
breaks the usage case of live migration like CRIU or similar.  Also for
some interfaces that do not query information from kernel, most usages
can be optimized away by either building glibc with a minimum 5.1 kernel
or by using the 32-bit syscall for the common case.

So the following patch implement this optimization for the interfaces
that allows it.  If the provided timeout can be fit in old 32-bit
time_t, the old syscall is used instead.  This optimization is only used
for !__ASSUME_TIME64_SYSCALLS, otherwise the newer 64-bit syscall are
used.

I checked this with 3 different configation which should cover most
usages:

  - i686-linux-gnu on a 4.15 kernel and default --enable-kernel=3.2.
    This uses the 32-bit optimization to avoid calling the newer
    64-bit syscall when possible.  It also triggers and EOVERFLOW
    when 64-bit inputs are used without proper kernel support.
  - i686-linux-gnu on a 5.11 kernel and default --enable-kernel=3.2.
    This will also use the 32-bit optimization, but it will always
    succeded due proper kernel support.
  - i686-linux-gnu on a 5.11 kernel and with --enable-kernel=5.1.
    This enables __ASSUME_TIME64_SYSCALLS and only uses 64-bit
    time_t syscalls.

Adhemerval Zanella (18):
  Use 64 bit time_t stat internally
  Use LFS and 64 bit time for installed programs
  support: Add support_create_timer
  linux: Only use 64-bit syscall if required for ppoll
  linux: Only use 64-bit syscall if required for pselect
  linux: Only use 64-bit syscall if required for select
  linux: Remove supports_time64 () from clock_getres
  linux: Remove supports_time64 () from clock_gettime
  linux: Remove time64-support
  linux: timerfd_gettime minor cleanup
  linux: Only use 64-bit syscall if required for semtimedop
  linux: Only use 64-bit syscall if required for timerfd_settime
  linux: Only use 64-bit syscall if required for mq_timedreceive
  linux: Only use 64-bit syscall if required for mq_timedsend
  linux: Only use 64-bit syscall if required for sigtimedwait
  linux: Only use 64-bit syscall if required for utimensat family
  linux: Only use 64-bit syscall if required for internal futex
  linux: Only use 64-bit syscall if required for clock_nanosleep

 Makeconfig                                    |   8 +-
 Makerules                                     |  12 +-
 csu/check_fds.c                               |   8 +-
 elf/dl-load.c                                 |   8 +-
 elf/dl-misc.c                                 |   4 +-
 elf/dl-profile.c                              |   4 +-
 iconv/gconv_cache.c                           |   4 +-
 include/dirent.h                              |   2 +-
 include/file_change_detection.h               |   6 +-
 include/sys/select.h                          |   5 +
 inet/rcmd.c                                   |   6 +-
 intl/loadmsgcat.c                             |   4 +-
 io/Makefile                                   |   4 +-
 io/file_change_detection.c                    |  16 ++-
 io/getdirname.c                               |   6 +-
 libio/filedoalloc.c                           |   2 +-
 libio/fileops.c                               |   8 +-
 libio/oldfileops.c                            |   2 +-
 libio/wfileops.c                              |   2 +-
 locale/loadarchive.c                          |   8 +-
 locale/loadlocale.c                           |   6 +-
 locale/localeinfo.h                           |   2 +-
 misc/Makefile                                 |  11 ++
 misc/tst-pselect.c                            | 120 ++++++++----------
 misc/tst-select.c                             |  39 +++---
 nptl/futex-internal.c                         |  52 +++++---
 nscd/nscd_helper.c                            |   4 +-
 nss/nss_database.c                            |   4 +-
 rt/Makefile                                   |   4 +-
 rt/tst-mqueue10-time64.c                      |   1 +
 rt/tst-mqueue10.c                             |  72 +++++++++++
 support/Makefile                              |   1 +
 support/support.h                             |  11 ++
 support/support_create_timer.c                |  69 ++++++++++
 sysdeps/nptl/futex-internal.h                 |  24 ++--
 sysdeps/posix/dl-fileid.h                     |   4 +-
 sysdeps/posix/euidaccess.c                    |   4 +-
 sysdeps/posix/getaddrinfo.c                   |  21 +--
 sysdeps/posix/getcwd.c                        |  15 ++-
 sysdeps/posix/pathconf.c                      |   4 +-
 sysdeps/posix/sysconf.c                       |   4 +-
 sysdeps/posix/tempname.c                      |   8 +-
 sysdeps/unix/sysv/linux/Makefile              |  15 ++-
 sysdeps/unix/sysv/linux/clock_getres.c        |  16 +--
 sysdeps/unix/sysv/linux/clock_gettime.c       |  14 +-
 sysdeps/unix/sysv/linux/clock_nanosleep.c     |  47 ++++---
 sysdeps/unix/sysv/linux/fdopendir.c           |   4 +-
 sysdeps/unix/sysv/linux/fexecve.c             |   4 +-
 .../unix/sysv/linux/microblaze/pselect32.c    |   3 +-
 sysdeps/unix/sysv/linux/mq_timedreceive.c     |  35 ++---
 sysdeps/unix/sysv/linux/mq_timedsend.c        |  35 ++---
 sysdeps/unix/sysv/linux/opendir.c             |   7 +-
 sysdeps/unix/sysv/linux/pathconf.c            |   5 +-
 sysdeps/unix/sysv/linux/ppoll.c               |  41 +++---
 sysdeps/unix/sysv/linux/pselect.c             |  47 ++++---
 sysdeps/unix/sysv/linux/pselect32.c           |   6 -
 sysdeps/unix/sysv/linux/select.c              |  60 +++------
 sysdeps/unix/sysv/linux/select32.c            |  58 +++++++++
 sysdeps/unix/sysv/linux/semtimedop.c          |  54 ++++----
 sysdeps/unix/sysv/linux/sigtimedwait.c        |  26 ++--
 sysdeps/unix/sysv/linux/time64-support.c      |  23 ----
 sysdeps/unix/sysv/linux/time64-support.h      |  70 ----------
 sysdeps/unix/sysv/linux/timerfd_gettime.c     |  10 +-
 sysdeps/unix/sysv/linux/timerfd_settime.c     |  25 ++--
 sysdeps/unix/sysv/linux/tst-ppoll.c           |  15 +++
 sysdeps/unix/sysv/linux/tst-sigtimedwait.c    |  18 +++
 sysdeps/unix/sysv/linux/tst-timerfd.c         |  29 ++++-
 sysdeps/unix/sysv/linux/ttyname.h             |  10 +-
 sysdeps/unix/sysv/linux/ttyname_r.c           |  16 +--
 sysdeps/unix/sysv/linux/utimensat.c           |  35 +++--
 sysvipc/Makefile                              |   9 ++
 sysvipc/ftok.c                                |   4 +-
 sysvipc/test-sysvsem.c                        |  22 +++-
 time/Makefile                                 |   9 ++
 time/tst-clock_nanosleep.c                    |  40 +++---
 time/tzfile.c                                 |   6 +-
 76 files changed, 851 insertions(+), 566 deletions(-)
 create mode 100644 rt/tst-mqueue10-time64.c
 create mode 100644 rt/tst-mqueue10.c
 create mode 100644 support/support_create_timer.c
 create mode 100644 sysdeps/unix/sysv/linux/select32.c
 delete mode 100644 sysdeps/unix/sysv/linux/time64-support.c
 delete mode 100644 sysdeps/unix/sysv/linux/time64-support.h

-- 
2.30.2



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