linux.git/Documentation/admin-guide/sysctl, branch v5.7

docs: admin-guide: merge sections for the kernel.modprobe sysctl

2020-04-15T20:50:09+00:00

Documentation for the kernel.modprobe sysctl was added both by
commit 0317c5371e6a ("docs: merge debugging-modules.txt into
sysctl/kernel.rst") and by commit 6e7158250625 ("docs: admin-guide:
document the kernel.modprobe sysctl"), resulting in the same sysctl
being documented in two places.  Merge these into one place.

Signed-off-by: Eric Biggers 
Reviewed-by: Stephen Kitt 
Link: https://lore.kernel.org/r/20200414172430.230293-1-ebiggers@kernel.org
Signed-off-by: Jonathan Corbet

Merge tag 'timers-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2020-04-12T17:13:14+00:00

Pull time(keeping) updates from Thomas Gleixner:

 - Fix the time_for_children symlink in /proc/$PID/ so it properly
   reflects that it part of the 'time' namespace

 - Add the missing userns limit for the allowed number of time
   namespaces, which was half defined but the actual array member was
   not added. This went unnoticed as the array has an exessive empty
   member at the end but introduced a user visible regression as the
   output was corrupted.

 - Prevent further silent ucount corruption by adding a BUILD_BUG_ON()
   to catch half updated data.

* tag 'timers-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ucount: Make sure ucounts in /proc/sys/user don't regress again
  time/namespace: Add max_time_namespaces ucount
  time/namespace: Fix time_for_children symlink

docs: admin-guide: document the kernel.modprobe sysctl

2020-04-10T22:36:22+00:00

Document the kernel.modprobe sysctl in the same place that all the other
kernel.* sysctls are documented.  Make sure to mention how to use this
sysctl to completely disable module autoloading, and how this sysctl
relates to CONFIG_STATIC_USERMODEHELPER.

[ebiggers@google.com: v5]
  Link: http://lkml.kernel.org/r/20200318230515.171692-4-ebiggers@kernel.org
Signed-off-by: Eric Biggers 
Signed-off-by: Andrew Morton 
Cc: Alexei Starovoitov 
Cc: Greg Kroah-Hartman 
Cc: Jeff Vander Stoep 
Cc: Jessica Yu 
Cc: Kees Cook 
Cc: Luis Chamberlain 
Cc: NeilBrown 
Link: http://lkml.kernel.org/r/20200312202552.241885-4-ebiggers@kernel.org
Signed-off-by: Linus Torvalds

time/namespace: Add max_time_namespaces ucount

2020-04-07T10:37:21+00:00

Michael noticed that userns limit for number of time namespaces is missing.

Furthermore, time namespace introduced UCOUNT_TIME_NAMESPACES, but didn't
introduce an array member in user_table[]. It would make array's
initialisation OOB write, but by luck the user_table array has an excessive
empty member (all accesses to the array are limited with UCOUNT_COUNTS - so
it silently reuses the last free member.

Fixes user-visible regression: max_inotify_instances by reason of the
missing UCOUNT_ENTRY() has limited max number of namespaces instead of the
number of inotify instances.

Fixes: 769071ac9f20 ("ns: Introduce Time Namespace")
Reported-by: Michael Kerrisk (man-pages) 
Signed-off-by: Dmitry Safonov 
Signed-off-by: Thomas Gleixner 
Acked-by: Andrei Vagin 
Acked-by: Vincenzo Frascino 
Cc: stable@kernel.org
Link: https://lkml.kernel.org/r/20200406171342.128733-1-dima@arista.com

mm/compaction: Disable compact_unevictable_allowed on RT

2020-04-02T16:35:31+00:00

Since commit 5bbe3547aa3ba ("mm: allow compaction of unevictable pages")
it is allowed to examine mlocked pages and compact them by default.  On
-RT even minor pagefaults are problematic because it may take a few 100us
to resolve them and until then the task is blocked.

Make compact_unevictable_allowed = 0 default and issue a warning on RT if
it is changed.

[bigeasy@linutronix.de: v5]
  Link: https://lore.kernel.org/linux-mm/20190710144138.qyn4tuttdq6h7kqx@linutronix.de/
  Link: http://lkml.kernel.org/r/20200319165536.ovi75tsr2seared4@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior 
Signed-off-by: Andrew Morton 
Reviewed-by: Andrew Morton 
Acked-by: Mel Gorman 
Acked-by: Vlastimil Babka 
Cc: Thomas Gleixner 
Cc: Luis Chamberlain 
Cc: Kees Cook 
Cc: Iurii Zaikin 
Cc: Vlastimil Babka 
Link: https://lore.kernel.org/linux-mm/20190710144138.qyn4tuttdq6h7kqx@linutronix.de/
Link: http://lkml.kernel.org/r/20200303202225.nhqc3v5gwlb7x6et@linutronix.de
Signed-off-by: Linus Torvalds

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

2020-04-01T00:29:33+00:00

Pull networking updates from David Miller:
 "Highlights:

   1) Fix the iwlwifi regression, from Johannes Berg.

   2) Support BSS coloring and 802.11 encapsulation offloading in
      hardware, from John Crispin.

   3) Fix some potential Spectre issues in qtnfmac, from Sergey
      Matyukevich.

   4) Add TTL decrement action to openvswitch, from Matteo Croce.

   5) Allow paralleization through flow_action setup by not taking the
      RTNL mutex, from Vlad Buslov.

   6) A lot of zero-length array to flexible-array conversions, from
      Gustavo A. R. Silva.

   7) Align XDP statistics names across several drivers for consistency,
      from Lorenzo Bianconi.

   8) Add various pieces of infrastructure for offloading conntrack, and
      make use of it in mlx5 driver, from Paul Blakey.

   9) Allow using listening sockets in BPF sockmap, from Jakub Sitnicki.

  10) Lots of parallelization improvements during configuration changes
      in mlxsw driver, from Ido Schimmel.

  11) Add support to devlink for generic packet traps, which report
      packets dropped during ACL processing. And use them in mlxsw
      driver. From Jiri Pirko.

  12) Support bcmgenet on ACPI, from Jeremy Linton.

  13) Make BPF compatible with RT, from Thomas Gleixnet, Alexei
      Starovoitov, and your's truly.

  14) Support XDP meta-data in virtio_net, from Yuya Kusakabe.

  15) Fix sysfs permissions when network devices change namespaces, from
      Christian Brauner.

  16) Add a flags element to ethtool_ops so that drivers can more simply
      indicate which coalescing parameters they actually support, and
      therefore the generic layer can validate the user's ethtool
      request. Use this in all drivers, from Jakub Kicinski.

  17) Offload FIFO qdisc in mlxsw, from Petr Machata.

  18) Support UDP sockets in sockmap, from Lorenz Bauer.

  19) Fix stretch ACK bugs in several TCP congestion control modules,
      from Pengcheng Yang.

  20) Support virtual functiosn in octeontx2 driver, from Tomasz
      Duszynski.

  21) Add region operations for devlink and use it in ice driver to dump
      NVM contents, from Jacob Keller.

  22) Add support for hw offload of MACSEC, from Antoine Tenart.

  23) Add support for BPF programs that can be attached to LSM hooks,
      from KP Singh.

  24) Support for multiple paths, path managers, and counters in MPTCP.
      From Peter Krystad, Paolo Abeni, Florian Westphal, Davide Caratti,
      and others.

  25) More progress on adding the netlink interface to ethtool, from
      Michal Kubecek"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2121 commits)
  net: ipv6: rpl_iptunnel: Fix potential memory leak in rpl_do_srh_inline
  cxgb4/chcr: nic-tls stats in ethtool
  net: dsa: fix oops while probing Marvell DSA switches
  net/bpfilter: remove superfluous testing message
  net: macb: Fix handling of fixed-link node
  net: dsa: ksz: Select KSZ protocol tag
  netdevsim: dev: Fix memory leak in nsim_dev_take_snapshot_write
  net: stmmac: add EHL 2.5Gbps PCI info and PCI ID
  net: stmmac: add EHL PSE0 & PSE1 1Gbps PCI info and PCI ID
  net: stmmac: create dwmac-intel.c to contain all Intel platform
  net: dsa: bcm_sf2: Support specifying VLAN tag egress rule
  net: dsa: bcm_sf2: Add support for matching VLAN TCI
  net: dsa: bcm_sf2: Move writing of CFP_DATA(5) into slicing functions
  net: dsa: bcm_sf2: Check earlier for FLOW_EXT and FLOW_MAC_EXT
  net: dsa: bcm_sf2: Disable learning for ASP port
  net: dsa: b53: Deny enslaving port 7 for 7278 into a bridge
  net: dsa: b53: Prevent tagged VLAN on port 7 for 7278
  net: dsa: b53: Restore VLAN entries upon (re)configuration
  net: dsa: bcm_sf2: Fix overflow checks
  hv_netvsc: Remove unnecessary round_up for recv_completion_cnt
  ...

Documentation: Better document the softlockup_panic sysctl

2020-03-10T19:55:55+00:00

Commit 9c44bc03fff4 ("softlockup: allow panic on lockup") added the
softlockup_panic sysctl, but didn't add information about it to the file
Documentation/admin-guide/sysctl/kernel.rst (which in that time certainly
wasn't rst and had other name!).

This patch just adds the respective documentation and references it from
the corresponding entry in Documentation/admin-guide/kernel-parameters.txt.

This patch was strongly based on Scott Wood's commit d22881dc13b6
("Documentation: Better document the hardlockup_panic sysctl").

Reviewed-by: Kees Cook 
Signed-off-by: Guilherme G. Piccoli 
Link: https://lore.kernel.org/r/20200310183649.23163-1-gpiccoli@canonical.com
Signed-off-by: Jonathan Corbet

bpf, doc: Add BPF JIT for RV32G to BPF documentation

2020-03-05T15:13:47+00:00

Update filter.txt and admin-guide to mention the BPF JIT for RV32G.

Co-developed-by: Xi Wang 
Signed-off-by: Xi Wang 
Signed-off-by: Luke Nelson 
Signed-off-by: Daniel Borkmann 
Reviewed-by: Björn Töpel 
Acked-by: Björn Töpel 
Link: https://lore.kernel.org/bpf/20200305050207.4159-4-luke.r.nels@gmail.com

docs: add a script to check sysctl docs

2020-02-25T10:35:16+00:00

This script allows sysctl documentation to be checked against the
kernel source code, to identify missing or obsolete entries. Running
it against 5.5 shows for example that sysctl/kernel.rst has two
obsolete entries and is missing 52 entries.

Signed-off-by: Stephen Kitt 
Signed-off-by: Jonathan Corbet

docs: sysctl/kernel: document acpi_video_flags

2020-02-25T10:27:23+00:00

Based on the implementation in arch/x86/kernel/acpi/sleep.c, in
particular the acpi_sleep_setup() function.

Signed-off-by: Stephen Kitt 
Signed-off-by: Jonathan Corbet