linux_dsm_epyc7002/arch/x86
Linus Torvalds 5450e8a316 pidfd-updates-v5.3
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Merge tag 'pidfd-updates-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull pidfd updates from Christian Brauner:
 "This adds two main features.

   - First, it adds polling support for pidfds. This allows process
     managers to know when a (non-parent) process dies in a race-free
     way.

     The notification mechanism used follows the same logic that is
     currently used when the parent of a task is notified of a child's
     death. With this patchset it is possible to put pidfds in an
     {e}poll loop and get reliable notifications for process (i.e.
     thread-group) exit.

   - The second feature compliments the first one by making it possible
     to retrieve pollable pidfds for processes that were not created
     using CLONE_PIDFD.

     A lot of processes get created with traditional PID-based calls
     such as fork() or clone() (without CLONE_PIDFD). For these
     processes a caller can currently not create a pollable pidfd. This
     is a problem for Android's low memory killer (LMK) and service
     managers such as systemd.

  Both patchsets are accompanied by selftests.

  It's perhaps worth noting that the work done so far and the work done
  in this branch for pidfd_open() and polling support do already see
  some adoption:

   - Android is in the process of backporting this work to all their LTS
     kernels [1]

   - Service managers make use of pidfd_send_signal but will need to
     wait until we enable waiting on pidfds for full adoption.

   - And projects I maintain make use of both pidfd_send_signal and
     CLONE_PIDFD [2] and will use polling support and pidfd_open() too"

[1] https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.9+backport%22
    https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.14+backport%22
    https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.19+backport%22

[2] aab6e3eb73/src/lxc/start.c (L1753)

* tag 'pidfd-updates-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  tests: add pidfd_open() tests
  arch: wire-up pidfd_open()
  pid: add pidfd_open()
  pidfd: add polling selftests
  pidfd: add polling support
2019-07-10 22:17:21 -07:00
..
boot It's been a relatively busy cycle for docs: 2019-07-09 12:34:26 -07:00
configs x86/defconfigs: Remove useless UEVENT_HELPER_PATH 2019-06-21 19:22:08 +02:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-07-08 20:57:08 -07:00
entry pidfd-updates-v5.3 2019-07-10 22:17:21 -07:00
events Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-07-09 11:15:52 -07:00
hyperv clocksource/drivers: Continue making Hyper-V clocksource ISA agnostic 2019-07-03 11:00:59 +02:00
ia32 treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
include It's been a relatively busy cycle for docs: 2019-07-09 12:34:26 -07:00
kernel It's been a relatively busy cycle for docs: 2019-07-09 12:34:26 -07:00
kvm Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-07-08 11:59:59 -07:00
lib Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-07-08 10:39:56 -07:00
math-emu x86/fpu: Always init the state in fpu__clear() 2019-04-09 19:28:06 +02:00
mm It's been a relatively busy cycle for docs: 2019-07-09 12:34:26 -07:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-17 15:55:34 -07:00
oprofile
pci treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 387 2019-06-05 17:37:11 +02:00
platform It's been a relatively busy cycle for docs: 2019-07-09 12:34:26 -07:00
power SPDX update for 5.2-rc4 2019-06-08 12:52:42 -07:00
purgatory treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230 2019-06-19 17:09:06 +02:00
ras RAS/CEC: Add CONFIG_RAS_CEC_DEBUG and move CEC debug features there 2019-06-08 17:39:24 +02:00
realmode x86/realmode: Make set_real_mode_mem() static inline 2019-03-29 10:16:27 +01:00
tools Merge branch 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-07-08 17:34:44 -07:00
um Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2019-07-08 21:48:15 -07:00
video treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
xen Merge branch 'x86-topology-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-07-08 18:28:44 -07:00
.gitignore
Kbuild treewide: Add SPDX license identifier - Kbuild 2019-05-30 11:32:33 -07:00
Kconfig It's been a relatively busy cycle for docs: 2019-07-09 12:34:26 -07:00
Kconfig.cpu x86/cpu: Create Zhaoxin processors architecture support file 2019-06-22 11:45:57 +02:00
Kconfig.debug It's been a relatively busy cycle for docs: 2019-07-09 12:34:26 -07:00
Makefile x86/build: Keep local relocations with ld.lld 2019-04-05 12:34:35 +02:00
Makefile_32.cpu
Makefile.um x86, powerpc: Remove -funit-at-a-time compiler option entirely 2018-12-09 11:55:32 +01:00