Commit Graph

32857 Commits

Author SHA1 Message Date
Paul E. McKenney
3b2a473985 rcutorture: Add KCSAN stubs
This commit adds stubs for KCSAN's data_race(), ASSERT_EXCLUSIVE_WRITER(),
and ASSERT_EXCLUSIVE_ACCESS() macros to allow code using these macros to
move ahead.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-04-27 11:05:13 -07:00
Paul E. McKenney
353159365e rcu: Add KCSAN stubs
This commit adds stubs for KCSAN's data_race(), ASSERT_EXCLUSIVE_WRITER(),
and ASSERT_EXCLUSIVE_ACCESS() macros to allow code using these macros to
move ahead.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-04-27 11:00:06 -07:00
Linus Torvalds
3e0dea5768 An update for the proc interface of time namespaces: Use symbolic names
instead of clockid numbers. The usability nuisance of numbers was noticed
 by Michael when polishing the man page.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl6cVQsTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoWBjEAC0dCUHKDLoG0FeyG4tb4FEBW2iTqM8
 UFirH26K18s8QSePdvfJlaxtN2SdfNZG7UgYN7wz1fDFQy05zTz7Rek8UrDuu3rh
 mVph/UZtUJl+6ypW2Lw9x5RWpT5yzay2iowUyBPnNxU9F/0uRKvXQFju3L83Lo/z
 Z4ni7gVEw87dQi5E74tEv6iaydgPuCBpGxoMahotnHyclqMjA0QuAK6nhN5ZTcAn
 senoorS/VqkSF5qEvIUwe7+F+kkMbwQryT7merJyNwh/F49xTTXRyBmiys1MF8Og
 MTEvldXKy2pCh2UfRa/x84WWwOUVNivTXdIXjhalsblczL0j1z9MsQ8b3AOXOiLf
 S+/Ntbb2dGo4qE22jekMwZ54Pm4x5NzChCU8+3pvd6IrPWZKi6vue74Kd0RNHQg/
 0kWOlZnIP2ArVW0bFqV6jhMYkjmVdK6gm7cUpFV66L2H8zbfFuc4OlxJYEFYivye
 9Yck+rFQmMwA15ZXYIpggkd7Rf/5CGF1CiMBAvP/ILubpgbJqnn6/tGByq8tDKdy
 mqXX+NHF0M/7rJd5vr7wP6p3E5nQ9l/41rh9ii9EDLXf4jsWVO3EyobJ7fFHwprs
 5tTWGxVJymUQLq/LQPXOVVENGK+ZsXXNGn/4n8IOVroeypxADTGyhtSh122kFFhv
 jPcVHqpBUd0g4Q==
 =slEk
 -----END PGP SIGNATURE-----

Merge tag 'timers-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull time namespace fix from Thomas Gleixner:
 "An update for the proc interface of time namespaces: Use symbolic
  names instead of clockid numbers. The usability nuisance of numbers
  was noticed by Michael when polishing the man page"

* tag 'timers-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  proc, time/namespace: Show clock symbolic names in /proc/pid/timens_offsets
2020-04-19 11:46:21 -07:00
Linus Torvalds
80ade29e1e A set of fixes/updates for the interrupt subsystem:
- Remove setup_irq() and remove_irq(). All users have been converted so
    remove them before new users surface.
 
  - A set of bugfixes for various interrupt chip drivers
 
  - Add a few missing static attributes to address sparse warnings.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl6cUuMTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoYi7EACOFPrwdOlKqDdgU1FGReEzhJeNSSyH
 yUp1m2nNckz8Y2B+ihnLsfvcktZSXYRuDTZ/u/rmaKqq2wH5Q/h4DNQxEfoMNUep
 IVBlvAFcGsvpdSbrlc+nx6sEo0K2b22AQVHdyPECiQYFZJikstAtEfzEv+ZaUr2S
 Lcds295BIQylbugQpcVZL73j6iUKQ+P5YU0Wlkd/Vhlnxe9UdMd/N1P3GoRaRlOa
 QxYDJCnZJjWkN+cEVRCAZVTat6pd3zaMHvEabI39Lzx4U+nu4vh62TILwk+wdpuA
 DzgA+ENFXzv2zLlnF8gB0wKWw3J99No9gfRpuK/vWBQ68UeZsPlM5PKEr93oD4cC
 To9D70r71UM+LS+Km8ciFlqeT4N+hIMb/x8rpIf5Tcfn5spXjNEhR4U6/d/D2ZYy
 cQiu82th9kSOMGBhlrfkJ0gAT20UfAktDHU1M4JhwI5Y/DLusb6mfg0CRMj8ucOV
 0xrKkgHxhX162oRTKzy5OTMWQRGTvIQZg1QE3xxtrT2qCq4ypu0EHQbh3GdfcIVQ
 8n+s/Dde6etmbSwDDdEuRi///zM+hvaiXi5KOV28LYgRDbU78cAX8uRgX9sq2pg+
 WxK9ulprkW6Ci1yTts9Q6FY+ZBekg7NBKXXDCJdPwXxTLRrdci68pPZip12AaWxP
 2HYxWhE8LvmKAw==
 =jaX5
 -----END PGP SIGNATURE-----

Merge tag 'irq-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq fixes from Thomas Gleixner:
 "A set of fixes/updates for the interrupt subsystem:

   - Remove setup_irq() and remove_irq(). All users have been converted
     so remove them before new users surface.

   - A set of bugfixes for various interrupt chip drivers

   - Add a few missing static attributes to address sparse warnings"

* tag 'irq-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/irq-bcm7038-l1: Make bcm7038_l1_of_init() static
  irqchip/irq-mvebu-icu: Make legacy_bindings static
  irqchip/meson-gpio: Fix HARDIRQ-safe -> HARDIRQ-unsafe lock order
  irqchip/sifive-plic: Fix maximum priority threshold value
  irqchip/ti-sci-inta: Fix processing of masked irqs
  irqchip/mbigen: Free msi_desc on device teardown
  irqchip/gic-v4.1: Update effective affinity of virtual SGIs
  irqchip/gic-v4.1: Add support for VPENDBASER's Dirty+Valid signaling
  genirq: Remove setup_irq() and remove_irq()
2020-04-19 11:23:33 -07:00
Linus Torvalds
08dd387277 Two fixes for the scheduler:
- Work around an uninitializaed variable warning where GCC can't figure it
    out.
 
  - Allow 'isolcpus=' to skip unknown subparameters so that older kernels
    work with the commandline of a newer kernel. Improve the error output
    while at it.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl6cVFwTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoZAaD/9i9QgLuj1Ka59kNPAs68i5Kjar72VS
 us1dM2n0Tx6lIUEYsdJsu4GTRi5NEBqLbmwSgsXROnhI6Jd17hHp5JViezk1GZWc
 Zg2uARAj9Jsqh2q5IjriNOwzq47PDC4dmSUzaecJff8PqGkk9Lpry6qvx3A02uSn
 tVVQAXqwCbPTaQzuhEf/q6mbfRaO90tVqGdseD+1wE0FBFfPLwddegLEGhL1vYsA
 55UhpKCGsS9lrfmgkxk1Xb3e0pJBObiV0SXdn2qHqJTpVUaDTZzsWgJHXg+0Fe1V
 0ZsuGfmaaisYPBZmqRo4HALbkgnvVECSbp7FAnhvqiQMyNaciiwkkFv9Ap5+aayf
 c8wXz/emAmuEMNzipovyFUITCIOs6IL1CkESsbO8Bgx9sTHO+pcgNEYrsX1953UC
 45GjhXR3ymnclqsVqfMWIcNRukk0g9W38yp1DgA5IIhVz1rHogEquD9F10qsCGb1
 FgSOnyGlU0I0JR5tEfqR0TeCuqLGKB2NvnEgLU4OVpsdEC5ac87uvzWEZuOmR5Z4
 vQCkps1z1ABW5fB/kFO83OiA5BZfDGnq5Vvh6XDOv6EeWjhIXrolu6VeTYpBSInq
 w0oNpsaA9wsy7WIy1RJ8jtSNsgS8fULCE5lUBtFeSUY/T7IcWd0lwnTlL97A4qzg
 GdYVT/UAHLCzCA==
 =AKgh
 -----END PGP SIGNATURE-----

Merge tag 'sched-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler fixes from Thomas Gleixner:
 "Two fixes for the scheduler:

   - Work around an uninitialized variable warning where GCC can't
     figure it out.

   - Allow 'isolcpus=' to skip unknown subparameters so that older
     kernels work with the commandline of a newer kernel. Improve the
     error output while at it"

* tag 'sched-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/vtime: Work around an unitialized variable warning
  sched/isolation: Allow "isolcpus=" to skip unknown sub-parameters
2020-04-19 11:18:20 -07:00
Linus Torvalds
5e7de58127 A single bugfix for RCU to prevent taking a lock in NMI context.
-----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl6cUf8THHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYofFtD/92Ufh1t+1uSe/txUJ/lTdY98cpcD5i
 UZJYdF102VLkhwA3Ors0Udtrnvuyxb5FFSfJZ3/N7tsNaXgcz1QOQsqoZz4SSgLJ
 pPj+2v+LNI6rIWDXuwszbLM/nT1mJGAK9NQ6+AhvIyBMPbht4/Lajsv7vkFMTzXw
 8o+a5NqLKWDca7/eLcgbcMiSsulRZxRld0D7MSP7RBeEWeylt31q3JIBp7ldzJ77
 0KCdQEd3TAkP+hOZW98CNgcLgGtCxiOJ5EgjUOFJyD/+5mj219czKF53HXnn4amk
 5lmdzSB0RKV2JTNFKNZQOobgMPp8VIIf6R6QlDp5MdrGYWTIbV0p5Hak2u41Cyma
 BfxxkVZJipjC7mgAvZLgy0/Md7n2Eu5uAW0e72AYEmv7IwOGyHh9YL7IYiZQld67
 5q8xEgrIIpaCwscVjZqP3+GHc8KGWYuv8puMCeOk1v7UeWsRlc8j/eGWIXnY4E8v
 wvqWAB91dHlBh+CHaFtdy97buYinVzW/Tv2NTxLFKgxyGJTg82H2hdTpjRVYi5Z4
 DM2NQRLcD1ozvh8tsFzXWP+/uemlE+EUPBZofCjJ0WtzH1GWarf3YNqviFqldRLr
 GyEFoyIc3Ra/hTEzD9yCC0UWwJubhAVLWOuu9pJKuaaei8s1aiusABQGbz5sNG9l
 AcpB9KFMtsLAXA==
 =QjbA
 -----END PGP SIGNATURE-----

Merge tag 'core-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RCU fix from Thomas Gleixner:
 "A single bugfix for RCU to prevent taking a lock in NMI context"

* tag 'core-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rcu: Don't acquire lock in NMI handler in rcu_nmi_enter_common()
2020-04-19 11:16:00 -07:00
Linus Torvalds
774acb2a09 for-linus-2020-04-18
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXprWIAAKCRCRxhvAZXjc
 omUyAQCQcvJQhilLv0b7FtBAbN7+TkzV8vAQTzEITuHPa6m/HwEA2Gp9ZDTJfQbV
 T6utOrTm/LT0mfBkiDLSnLPtVzh7mgE=
 =Jz3d
 -----END PGP SIGNATURE-----

Merge tag 'for-linus-2020-04-18' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull thread fixes from Christian Brauner:
 "A few fixes and minor improvements:

   - Correctly validate the cgroup file descriptor when clone3() is used
     with CLONE_INTO_CGROUP.

   - Check that a new enough version of struct clone_args is passed
     which supports the cgroup file descriptor argument when
     CLONE_INTO_CGROUP is set in the flags argument.

   - Catch nonsensical struct clone_args layouts at build time.

   - Catch extensions of struct clone_args without updating the uapi
     visible size definitions at build time.

   - Check whether the signal is valid early in kill_pid_usb_asyncio()
     before doing further work.

   - Replace open-coded rcu_read_lock()+kill_pid_info()+rcu_read_unlock()
     sequence in kill_something_info() with kill_proc_info() which is a
     dedicated helper to do just that"

* tag 'for-linus-2020-04-18' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  clone3: add build-time CLONE_ARGS_SIZE_VER* validity checks
  clone3: add a check for the user struct size if CLONE_INTO_CGROUP is set
  clone3: fix cgroup argument sanity check
  signal: use kill_proc_info instead of kill_pid_info in kill_something_info
  signal: check sig before setting info in kill_pid_usb_asyncio
2020-04-18 11:38:51 -07:00
Linus Torvalds
c8372665b4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) Disable RISCV BPF JIT builds when !MMU, from Björn Töpel.

 2) nf_tables leaves dangling pointer after free, fix from Eric Dumazet.

 3) Out of boundary write in __xsk_rcv_memcpy(), fix from Li RongQing.

 4) Adjust icmp6 message source address selection when routes have a
    preferred source address set, from Tim Stallard.

 5) Be sure to validate HSR protocol version when creating new links,
    from Taehee Yoo.

 6) CAP_NET_ADMIN should be sufficient to manage l2tp tunnels even in
    non-initial namespaces, from Michael Weiß.

 7) Missing release firmware call in mlx5, from Eran Ben Elisha.

 8) Fix variable type in macsec_changelink(), caught by KASAN. Fix from
    Taehee Yoo.

 9) Fix pause frame negotiation in marvell phy driver, from Clemens
    Gruber.

10) Record RX queue early enough in tun packet paths such that XDP
    programs will see the correct RX queue index, from Gilberto Bertin.

11) Fix double unlock in mptcp, from Florian Westphal.

12) Fix offset overflow in ARM bpf JIT, from Luke Nelson.

13) marvell10g needs to soft reset PHY when coming out of low power
    mode, from Russell King.

14) Fix MTU setting regression in stmmac for some chip types, from
    Florian Fainelli.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (101 commits)
  amd-xgbe: Use __napi_schedule() in BH context
  mISDN: make dmril and dmrim static
  net: stmmac: dwmac-sunxi: Provide TX and RX fifo sizes
  net: dsa: mt7530: fix tagged frames pass-through in VLAN-unaware mode
  tipc: fix incorrect increasing of link window
  Documentation: Fix tcp_challenge_ack_limit default value
  net: tulip: make early_486_chipsets static
  dt-bindings: net: ethernet-phy: add desciption for ethernet-phy-id1234.d400
  ipv6: remove redundant assignment to variable err
  net/rds: Use ERR_PTR for rds_message_alloc_sgs()
  net: mscc: ocelot: fix untagged packet drops when enslaving to vlan aware bridge
  selftests/bpf: Check for correct program attach/detach in xdp_attach test
  libbpf: Fix type of old_fd in bpf_xdp_set_link_opts
  libbpf: Always specify expected_attach_type on program load if supported
  xsk: Add missing check on user supplied headroom size
  mac80211: fix channel switch trigger from unknown mesh peer
  mac80211: fix race in ieee80211_register_hw()
  net: marvell10g: soft-reset the PHY when coming out of low power
  net: marvell10g: report firmware version
  net/cxgb4: Check the return from t4_query_params properly
  ...
2020-04-16 14:52:29 -07:00
Andrei Vagin
94d440d618 proc, time/namespace: Show clock symbolic names in /proc/pid/timens_offsets
Michael Kerrisk suggested to replace numeric clock IDs with symbolic names.

Now the content of these files looks like this:
$ cat /proc/774/timens_offsets
monotonic      864000         0
boottime      1728000         0

For setting offsets, both representations of clocks (numeric and symbolic)
can be used.

As for compatibility, it is acceptable to change things as long as
userspace doesn't care. The format of timens_offsets files is very new and
there are no userspace tools yet which rely on this format.

But three projects crun, util-linux and criu rely on the interface of
setting time offsets and this is why it's required to continue supporting
the numeric clock IDs on write.

Fixes: 04a8682a71 ("fs/proc: Introduce /proc/pid/timens_offsets")
Suggested-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200411154031.642557-1-avagin@gmail.com
2020-04-16 12:10:54 +02:00
Borislav Petkov
e0d648f9d8 sched/vtime: Work around an unitialized variable warning
Work around this warning:

  kernel/sched/cputime.c: In function ‘kcpustat_field’:
  kernel/sched/cputime.c:1007:6: warning: ‘val’ may be used uninitialized in this function [-Wmaybe-uninitialized]

because GCC can't see that val is used only when err is 0.

Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200327214334.GF8015@zn.tnic
2020-04-15 11:06:50 +02:00
Peter Xu
3662daf023 sched/isolation: Allow "isolcpus=" to skip unknown sub-parameters
The "isolcpus=" parameter allows sub-parameters before the cpulist is
specified, and if the parser detects an unknown sub-parameters the whole
parameter will be ignored.

This design is incompatible with itself when new sub-parameters are added.
An older kernel will not recognize the new sub-parameter and will
invalidate the whole parameter so the CPU isolation will not take
effect. It emits a warning:

    isolcpus: Error, unknown flag

The better and compatible way is to allow "isolcpus=" to skip unknown
sub-parameters, so that even if new sub-parameters are added an older
kernel will still be able to behave as usual even if with the new
sub-parameter specified on the command line.

Ideally this should have been there when the first sub-parameter for
"isolcpus=" was introduced.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200403223517.406353-1-peterx@redhat.com
2020-04-15 10:38:26 +02:00
Eugene Syromiatnikov
a966dcfe15 clone3: add build-time CLONE_ARGS_SIZE_VER* validity checks
CLONE_ARGS_SIZE_VER* macros are defined explicitly and not via
the offsets of the relevant struct clone_args fields, which makes
it rather error-prone, so it probably makes sense to add some
compile-time checks for them (including the one that breaks
on struct clone_args extension as a reminder to add a relevant
size macro and a similar check).  Function copy_clone_args_from_user
seems to be a good place for such checks.

Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20200412202658.GA31499@asgard.redhat.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-04-15 09:56:32 +02:00
Eugene Syromiatnikov
62173872ca clone3: add a check for the user struct size if CLONE_INTO_CGROUP is set
Passing CLONE_INTO_CGROUP with an under-sized structure (that doesn't
properly contain cgroup field) seems like garbage input, especially
considering the fact that fd 0 is a valid descriptor.

Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20200412203123.GA5869@asgard.redhat.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-04-15 09:56:25 +02:00
Eugene Syromiatnikov
e82a118f57 clone3: fix cgroup argument sanity check
Checking that cgroup field value of struct clone_args is less than 0
is useless, as it is defined as unsigned 64-bit integer.  Moreover,
it doesn't catch the situations where its higher bits are lost during
the assignment to the cgroup field of the cgroup field of the internal
struct kernel_clone_args (where it is declared as signed 32-bit
integer), so it is still possible to pass garbage there.  A check
against INT_MAX solves both these issues.

Fixes: ef2c41cf38 ("clone3: allow spawning processes into cgroups")
Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20200412202533.GA29554@asgard.redhat.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-04-15 09:56:12 +02:00
Xiao Yang
0bbe7f7199 tracing: Fix the race between registering 'snapshot' event trigger and triggering 'snapshot' operation
Traced event can trigger 'snapshot' operation(i.e. calls snapshot_trigger()
or snapshot_count_trigger()) when register_snapshot_trigger() has completed
registration but doesn't allocate buffer for 'snapshot' event trigger.  In
the rare case, 'snapshot' operation always detects the lack of allocated
buffer so make register_snapshot_trigger() allocate buffer first.

trigger-snapshot.tc in kselftest reproduces the issue on slow vm:
-----------------------------------------------------------
cat trace
...
ftracetest-3028  [002] ....   236.784290: sched_process_fork: comm=ftracetest pid=3028 child_comm=ftracetest child_pid=3036
     <...>-2875  [003] ....   240.460335: tracing_snapshot_instance_cond: *** SNAPSHOT NOT ALLOCATED ***
     <...>-2875  [003] ....   240.460338: tracing_snapshot_instance_cond: *** stopping trace here!   ***
-----------------------------------------------------------

Link: http://lkml.kernel.org/r/20200414015145.66236-1-yangx.jy@cn.fujitsu.com

Cc: stable@vger.kernel.org
Fixes: 93e31ffbf4 ("tracing: Add 'snapshot' event trigger command")
Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-04-14 22:02:10 -04:00
Zou Wei
89f33dcadb bpf: remove unneeded conversion to bool in __mark_reg_unknown
This issue was detected by using the Coccinelle software:

  kernel/bpf/verifier.c:1259:16-21: WARNING: conversion to bool not needed here

The conversion to bool is unneeded, remove it.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/1586779076-101346-1-git-send-email-zou_wei@huawei.com
2020-04-14 21:40:06 +02:00
Andrii Nakryiko
1f6cb19be2 bpf: Prevent re-mmap()'ing BPF map as writable for initially r/o mapping
VM_MAYWRITE flag during initial memory mapping determines if already mmap()'ed
pages can be later remapped as writable ones through mprotect() call. To
prevent user application to rewrite contents of memory-mapped as read-only and
subsequently frozen BPF map, remove VM_MAYWRITE flag completely on initially
read-only mapping.

Alternatively, we could treat any memory-mapping on unfrozen map as writable
and bump writecnt instead. But there is little legitimate reason to map
BPF map as read-only and then re-mmap() it as writable through mprotect(),
instead of just mmap()'ing it as read/write from the very beginning.

Also, at the suggestion of Jann Horn, drop unnecessary refcounting in mmap
operations. We can just rely on VMA holding reference to BPF map's file
properly.

Fixes: fc9702273e ("bpf: Add mmap() support for BPF_MAP_TYPE_ARRAY")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jann Horn <jannh@google.com>
Link: https://lore.kernel.org/bpf/20200410202613.3679837-1-andriin@fb.com
2020-04-14 21:28:57 +02:00
afzal mohammed
07d8350ede genirq: Remove setup_irq() and remove_irq()
Now that all the users of setup_irq() & remove_irq() have been replaced by
request_irq() & free_irq() respectively, delete them.

Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lkml.kernel.org/r/0aa8771ada1ac8e1312f6882980c9c08bd023148.1585320721.git.afzal.mohd.ma@gmail.com
2020-04-14 10:08:50 +02:00
Ingo Molnar
40e7d7bdc1 Merge branch 'urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/urgent
Pull RCU fix from Paul E. McKenney.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-04-14 08:36:41 +02:00
Zhiqiang Liu
3075afdf15 signal: use kill_proc_info instead of kill_pid_info in kill_something_info
signal.c provides kill_proc_info, we can use it instead of kill_pid_info
in kill_something_info func gracefully.

Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/80236965-f0b5-c888-95ff-855bdec75bb3@huawei.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-04-12 22:46:34 +02:00
Zhiqiang Liu
eaec2b0bd3 signal: check sig before setting info in kill_pid_usb_asyncio
In kill_pid_usb_asyncio, if signal is not valid, we do not need to
set info struct.

Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/f525fd08-1cf7-fb09-d20c-4359145eb940@huawei.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-04-12 22:46:34 +02:00
Linus Torvalds
0785249f8b Time(keeping) updates:
- 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.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl6TFe4THHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYob4PD/47Qwz2z2mEeO037VbbI2gY4yl/raFo
 5KPWmnwonKrtVaYAldLutA3iaG7bBbUX5fRvbSRNTS6CJIHwwfLSx7/CeWMmIXEX
 0zsBsn5QXjG89lJZXM+ot74yzjvkeoad2g0jEHv92v0WDSXFiAWhkBUwknfNFbpa
 csEjkdpyn2zTVBGBzKVHWHXddkY0o0Q0JOy0EiH09rHGpQktPoLJdYp73VCygoJd
 NRAXhTmBQq85RMcSB3eVTbSPpIuBUzZke9zoio7YZwEjl6bkvSqetPmTdIr57u4s
 ex3PX++64EXD7r8ZW36fPGDqu6v0CH2ILK7QVhwyHAYJo2LQKVd+v25muaFrzfpn
 dSG1SqabWqdIHUoW/76ORyecAFLTzGwDu07UH+6VJbXeLfmuhe/LI3hdDQFph9NQ
 BOBKhaHm8aXmAmvrkxbbAikSkJYVHrAIp5abI4PSYoPaqK1DWnSPaT1cqtaIUgYL
 Mk15z19V9np4lMCH2cucAlap8U9EvQEIfCRRdl+crDu17ZzGID1pwhY2DA8adqcT
 SUfwzzUaykd5TZtDeIe+6G9fsgf/wbSTSSbrNGKlLXDbxx+iNVXErkmx0JXLEHV4
 47cmBwQZ255DzjMfuS4HzCck2MaaP8mDWgcbszgkP+GFnkf9EAP5XNp9st937mbG
 rzP+NkjNCldN9w==
 =wOiC
 -----END PGP SIGNATURE-----

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

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
2020-04-12 10:13:14 -07:00
Linus Torvalds
590680d139 Scheduler fixes/updates:
- Deduplicate the average computations in the scheduler core and the fair
    class code.
 
  - Fix a raise between runtime distribution and assignement which can cause
    exceeding the quota by up to 70%.
 
  - Prevent negative results in the imbalanace calculation
 
  - Remove a stale warning in the workqueue code which can be triggered
    since the call site was moved out of preempt disabled code. It's a false
    positive.
 
  - Deduplicate the print macros for procfs
 
  - Add the ucmap values to the SCHED_DEBUG procfs output for completness
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl6TFEoTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoRoPD/9cTERNZb/aT/SVD3TntBs5bMlnRR2U
 KsyoN7w2bmYGY6XbKdjWX+KorPyJ9YRcUpOfmH+6JmMioM5RrgCtAQ4cXP4q89k3
 6+hdHu+WAhp2AyKr5LAYZK+NYdq0fy/9xx7fdXNri8/QakQCy1vu/u6iiKRMmrEf
 R7zB7v4ddTOTKamUuGBNnmM4GwfrD7td9NksfjDqV4yJ2ZkaQ+apWAPzJK8ixfEa
 TGjVnnUZA82tZRZ+O4RDN2AVgG0CuXYRYPWRfqi3XgQ3d0+ju5mM7q+6TQeEUuAq
 19IoscLhmYGb9yYCY5p0j1AUkyr6FcSFr1SJt/8Jxpyw4JsKw+ANFBA3kkzEBZ+h
 0VcWjUw4S6A6+0HdrqUQYjr5tl7RCY+hOE+QQ/Xvrm4PpWi0L+1tB+kgR7VKNPO8
 Xqfp/CK7Rcgh2/nUHT4uxdwh4ZNsLo39QGTuahyPXzeRVJTEGUjbzktnEUVc9wmd
 OfjpC0Q2DBdXx+vnzH82flv/rtUUYor/Owhpq92E6d50Z7CjTa6xRNbmQUiVKls8
 jqehpRBUg5cB3TI0BKeb5+kzgeGDGpm7MfZbvSwvoL0stdJdzNwwc4nhOLjPkJFK
 R5m7cg82Kx+r/00Vb7k6WgYZ10WTS2Il1OKbgwHl5uTlaKuY7TPEIRVuJQV/XUSG
 88n4jIwpRbLMNw==
 =BVqY
 -----END PGP SIGNATURE-----

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

Pull scheduler fixes/updates from Thomas Gleixner:

 - Deduplicate the average computations in the scheduler core and the
   fair class code.

 - Fix a raise between runtime distribution and assignement which can
   cause exceeding the quota by up to 70%.

 - Prevent negative results in the imbalanace calculation

 - Remove a stale warning in the workqueue code which can be triggered
   since the call site was moved out of preempt disabled code. It's a
   false positive.

 - Deduplicate the print macros for procfs

 - Add the ucmap values to the SCHED_DEBUG procfs output for completness

* tag 'sched-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/debug: Add task uclamp values to SCHED_DEBUG procfs
  sched/debug: Factor out printing formats into common macros
  sched/debug: Remove redundant macro define
  sched/core: Remove unused rq::last_load_update_tick
  workqueue: Remove the warning in wq_worker_sleeping()
  sched/fair: Fix negative imbalance in imbalance calculation
  sched/fair: Fix race between runtime distribution and assignment
  sched/fair: Align rq->avg_idle and rq->avg_scan_cost
2020-04-12 10:09:19 -07:00
Linus Torvalds
20e2aa8126 Thre fixes/updates for perf:
- Fix the perf event cgroup tracking which tries to track the cgroup even
    for disabled events.
 
  - Add Ice Lake server support for uncore events
 
  - Disable pagefaults when retrieving the physical address in the sampling
    code.
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl6TEbMTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoYvgD/9Ufht3qrbE29oTS+q2x6PZRc01hvMW
 c3wh/7Anh5yBlTioUEl1tbNfSD1k9hKqMQJF6iPZQ4tzft6JAunstICngqJrJqSY
 si22mgY6QGKrA2+4UuxT7FZD5nrEhy1TrGNIOp/86Y9I59PAlrypWMxq71VUPjgB
 Yy9r6eSJqNX05r9tZy1WMloJaBBieaVvEefK9ZrO4s1XM/RU5pAl+/B1XauK8XN9
 e4bzu7d6r+w23pFuEqk3r4KWozafxczJAqV+w6/Me1lFgNj6m2GKq429bL/Bgj8d
 Re8N4donynPe9yvuDWS4eHD1z0nhOMQhOv85seBwBcEet0PnEPtyw/eUu2zZTE2J
 h1R7l8I3RIs9EmXtdoOuzLFbc8a9sw/lGQJYdP70TMEtLKPUcGkfNhwP196CRbZK
 TBVub3jP0STmo8u7PrkcMb53ZBZ17P317ous52f0xgkFB6YVqv29cB+NEyabjKMI
 fP9ZAaoJ9Rn7T9nji/8KsUcjpCUBhP//YWnf/Vax5PW+hkJhfrLOpesKpX1uAwzd
 fc4QzEXYr/a4YI30IvqSJBsJJZfvFl9ikMaXrv5TbR8nj/eszJInho5+olQj54A7
 SLzCOpVHc3jJ13d/C5Xjo0LhwSqjLv3JtvlFG34XHl+YlZUw0ua9u4Ld5vDIDYgw
 mwHHFp3P/yFAfQ==
 =5kqD
 -----END PGP SIGNATURE-----

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

Pull perf fixes from Thomas Gleixner:
 "Three fixes/updates for perf:

   - Fix the perf event cgroup tracking which tries to track the cgroup
     even for disabled events.

   - Add Ice Lake server support for uncore events

   - Disable pagefaults when retrieving the physical address in the
     sampling code"

* tag 'perf-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Disable page faults when getting phys address
  perf/x86/intel/uncore: Add Ice Lake server uncore support
  perf/cgroup: Correct indirection in perf_less_group_idx()
  perf/core: Fix event cgroup tracking
2020-04-12 10:05:24 -07:00
Linus Torvalds
652fa53caa Three small fixes/updates for the locking core code:
- Plug a task struct reference leak in the percpu rswem implementation.
 
  - Document the refcount interaction with PID_MAX_LIMIT
 
  - Improve the 'invalid wait context' data dump in lockdep so it contains
    all information which is required to decode the problem
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl6TEJoTHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoeY6D/42AKqIvpAPiPA+Aod9o8o7qDCoPJQN
 kwCx939+Mwrwm8YS3WJGJvR/jgoGeq33gerY93D0+jkMyhmvYeWbUIEdCenyy0+C
 tkA7pN1j61D7jMqmL8PgrObhQMM8tTdNNsiNxg5qZA8wI2oFBMbAStx5mCficCyJ
 8t3hh/2aRVlNN1MBjo25+jEWEXUIchAzmxnmR+5t/pRYWythOhLuWW05D8b1JoN3
 9zdHj9ZScONlrK+VmpXZl41SokT385arMXcmUuS+zPx6zl4P6yTgeHMLsm4Kt3+j
 1q0hm4fUEEW2IrF1Uc9pxtJh/39UVwvX8Wfj/wJLm3b1akmO+3tQ2cpiee4NHk2H
 WogvBNGG4QeGMrRkg0seiqUE6SOaNPXdGRszPc6EkzwpOywDjHVYV5qbII1VOpbK
 z/TJrtv8g8ejgAvyG0dEtEDydm2SqPAIAZFXj9JQ0I/gUZKTW5rvGQWdMXW6HPif
 wdJJ6xb4DC3f5DrBrXgpkMSdwfea2boIoLDMf9tCcdlRs6vmvY3iRLHy2xBLcRFt
 9yVDUxO40eJUxztbFKuZsQvgJyBxZubyK+Yo9CCvWQ95GfIr2JurIJEcD2fxVyRU
 57/Avt3zt7iViZ9LHJnL4JnWRxftWOdWusF2dsufmnuveCVhtA5B5bl7nGntpIT2
 mfJEDrJ7zzhgyA==
 =Agrh
 -----END PGP SIGNATURE-----

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

Pull locking fixes from Thomas Gleixner:
 "Three small fixes/updates for the locking core code:

   - Plug a task struct reference leak in the percpu rswem
     implementation.

   - Document the refcount interaction with PID_MAX_LIMIT

   - Improve the 'invalid wait context' data dump in lockdep so it
     contains all information which is required to decode the problem"

* tag 'locking-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/lockdep: Improve 'invalid wait context' splat
  locking/refcount: Document interaction with PID_MAX_LIMIT
  locking/percpu-rwsem: Fix a task_struct refcount
2020-04-12 09:47:10 -07:00
Linus Torvalds
75e7188397 dma-mapping fixes for 5.7
- fix an integer truncation in dma_direct_get_required_mask
    (Kishon Vijay Abraham)
  - fix the display of dma mapping types (Grygorii Strashko)
 -----BEGIN PGP SIGNATURE-----
 
 iQI/BAABCgApFiEEgdbnc3r/njty3Iq9D55TZVIEUYMFAl6Rfy8LHGhjaEBsc3Qu
 ZGUACgkQD55TZVIEUYPT3w/+MKNVGmyi6nSsruskr1CkLCah5GkHrDA4v+vwwkFZ
 zIeB7df/EOijzfYHlhEkiQWBcPvl9wmVBhFsuaY9XMQ/fJv06CpR5J2xtb+uZN9L
 HmfwCJPZwrHDqsonIiOtIWjyIOARLGC0CfBP+DCPJ/GDG9wys7eyfESh85PQEDvO
 QA4sPjJHuKeTTH2Q6QLM/aiqgr80Q4xrQLCVcgDAqAvqnCYi/E4HXty4pLNGpvJu
 5O2xzmbQT2l3gRXjxt5Ct4pol+nFmiWJ0sBDNVNUqge7vebBiu3e0VjEaeXUPAMq
 hQSrof2x+EwHITV10L82/poIKNQVVXW3aYgItMNXfOSBNqaNx4wVLRsrcMZWeMeJ
 0OHmCy6Sac2dK4QtY/NtZFLL1zW4ajsj8X975RjqBMcL6QAdCMxNSWGEY/j/fMQy
 FV1spy8FBfvXH+0O2POkYNBx/eICnMbGQ2ed5NZ8ONAl8wFLPM+2qIwmgb51a3TG
 8jR613Zqyw0aMnky0MUwvj5TlwwUyyXbGKpizl0vkFw7/NYXroNMaYWJSHF/ddFp
 vUChNqYhgCFY8FOhanFadyPxqU1InEoOkUS8/ij7NAR6cCrxsLuAohMYSNQJes3R
 IvmU36FtjO53rBdHaN4Eizk4EHVaZDxoll05UPU/B5IvzXqR6zy0PphoOxfzvmmq
 Qfk=
 =Af93
 -----END PGP SIGNATURE-----

Merge tag 'dma-mapping-5.7-1' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping fixes from Christoph Hellwig:

 - fix an integer truncation in dma_direct_get_required_mask
   (Kishon Vijay Abraham)

 - fix the display of dma mapping types (Grygorii Strashko)

* tag 'dma-mapping-5.7-1' of git://git.infradead.org/users/hch/dma-mapping:
  dma-debug: fix displaying of dma allocation type
  dma-direct: fix data truncation in dma_direct_get_required_mask()
2020-04-11 11:34:36 -07:00
Linus Torvalds
5b8b9d0c6d Merge branch 'akpm' (patches from Andrew)
Merge yet more updates from Andrew Morton:

 - Almost all of the rest of MM (memcg, slab-generic, slab, pagealloc,
   gup, hugetlb, pagemap, memremap)

 - Various other things (hfs, ocfs2, kmod, misc, seqfile)

* akpm: (34 commits)
  ipc/util.c: sysvipc_find_ipc() should increase position index
  kernel/gcov/fs.c: gcov_seq_next() should increase position index
  fs/seq_file.c: seq_read(): add info message about buggy .next functions
  drivers/dma/tegra20-apb-dma.c: fix platform_get_irq.cocci warnings
  change email address for Pali Rohár
  selftests: kmod: test disabling module autoloading
  selftests: kmod: fix handling test numbers above 9
  docs: admin-guide: document the kernel.modprobe sysctl
  fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once()
  kmod: make request_module() return an error when autoloading is disabled
  mm/memremap: set caching mode for PCI P2PDMA memory to WC
  mm/memory_hotplug: add pgprot_t to mhp_params
  powerpc/mm: thread pgprot_t through create_section_mapping()
  x86/mm: introduce __set_memory_prot()
  x86/mm: thread pgprot_t through init_memory_mapping()
  mm/memory_hotplug: rename mhp_restrictions to mhp_params
  mm/memory_hotplug: drop the flags field from struct mhp_restrictions
  mm/special: create generic fallbacks for pte_special() and pte_mkspecial()
  mm/vma: introduce VM_ACCESS_FLAGS
  mm/vma: define a default value for VM_DATA_DEFAULT_FLAGS
  ...
2020-04-10 17:57:48 -07:00
Vasily Averin
f4d74ef622 kernel/gcov/fs.c: gcov_seq_next() should increase position index
If seq_file .next function does not change position index, read after
some lseek can generate unexpected output.

https://bugzilla.kernel.org/show_bug.cgi?id=206283
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: NeilBrown <neilb@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Waiman Long <longman@redhat.com>
Link: http://lkml.kernel.org/r/f65c6ee7-bd00-f910-2f8a-37cc67e4ff88@virtuozzo.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:22 -07:00
Eric Biggers
d7d27cfc5c kmod: make request_module() return an error when autoloading is disabled
Patch series "module autoloading fixes and cleanups", v5.

This series fixes a bug where request_module() was reporting success to
kernel code when module autoloading had been completely disabled via
'echo > /proc/sys/kernel/modprobe'.

It also addresses the issues raised on the original thread
(https://lkml.kernel.org/lkml/20200310223731.126894-1-ebiggers@kernel.org/T/#u)
bydocumenting the modprobe sysctl, adding a self-test for the empty path
case, and downgrading a user-reachable WARN_ONCE().

This patch (of 4):

It's long been possible to disable kernel module autoloading completely
(while still allowing manual module insertion) by setting
/proc/sys/kernel/modprobe to the empty string.

This can be preferable to setting it to a nonexistent file since it
avoids the overhead of an attempted execve(), avoids potential
deadlocks, and avoids the call to security_kernel_module_request() and
thus on SELinux-based systems eliminates the need to write SELinux rules
to dontaudit module_request.

However, when module autoloading is disabled in this way,
request_module() returns 0.  This is broken because callers expect 0 to
mean that the module was successfully loaded.

Apparently this was never noticed because this method of disabling
module autoloading isn't used much, and also most callers don't use the
return value of request_module() since it's always necessary to check
whether the module registered its functionality or not anyway.

But improperly returning 0 can indeed confuse a few callers, for example
get_fs_type() in fs/filesystems.c where it causes a WARNING to be hit:

	if (!fs && (request_module("fs-%.*s", len, name) == 0)) {
		fs = __get_fs_type(name, len);
		WARN_ONCE(!fs, "request_module fs-%.*s succeeded, but still no fs?\n", len, name);
	}

This is easily reproduced with:

	echo > /proc/sys/kernel/modprobe
	mount -t NONEXISTENT none /

It causes:

	request_module fs-NONEXISTENT succeeded, but still no fs?
	WARNING: CPU: 1 PID: 1106 at fs/filesystems.c:275 get_fs_type+0xd6/0xf0
	[...]

This should actually use pr_warn_once() rather than WARN_ONCE(), since
it's also user-reachable if userspace immediately unloads the module.
Regardless, request_module() should correctly return an error when it
fails.  So let's make it return -ENOENT, which matches the error when
the modprobe binary doesn't exist.

I've also sent patches to document and test this case.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jeff Vander Stoep <jeffv@google.com>
Cc: Ben Hutchings <benh@debian.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200310223731.126894-1-ebiggers@kernel.org
Link: http://lkml.kernel.org/r/20200312202552.241885-1-ebiggers@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 15:36:22 -07:00
Sergey Senozhatsky
ab6f762f0f printk: queue wake_up_klogd irq_work only if per-CPU areas are ready
printk_deferred(), similarly to printk_safe/printk_nmi, does not
immediately attempt to print a new message on the consoles, avoiding
calls into non-reentrant kernel paths, e.g. scheduler or timekeeping,
which potentially can deadlock the system.

Those printk() flavors, instead, rely on per-CPU flush irq_work to print
messages from safer contexts.  For same reasons (recursive scheduler or
timekeeping calls) printk() uses per-CPU irq_work in order to wake up
user space syslog/kmsg readers.

However, only printk_safe/printk_nmi do make sure that per-CPU areas
have been initialised and that it's safe to modify per-CPU irq_work.
This means that, for instance, should printk_deferred() be invoked "too
early", that is before per-CPU areas are initialised, printk_deferred()
will perform illegal per-CPU access.

Lech Perczak [0] reports that after commit 1b710b1b10 ("char/random:
silence a lockdep splat with printk()") user-space syslog/kmsg readers
are not able to read new kernel messages.

The reason is printk_deferred() being called too early (as was pointed
out by Petr and John).

Fix printk_deferred() and do not queue per-CPU irq_work before per-CPU
areas are initialized.

Link: https://lore.kernel.org/lkml/aa0732c6-5c4e-8a8b-a1c1-75ebe3dca05b@camlintechnologies.com/
Reported-by: Lech Perczak <l.perczak@camlintechnologies.com>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Tested-by: Jann Horn <jannh@google.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: John Ogness <john.ogness@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-10 13:18:57 -07:00
Linus Torvalds
87ad46e601 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull proc fix from Eric Biederman:
 "A brown paper bag slipped through my proc changes, and syzcaller
  caught it when the code ended up in your tree.

  I have opted to fix it the simplest cleanest way I know how, so there
  is no reasonable chance for the bug to repeat"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  proc: Use a dedicated lock in struct pid
2020-04-10 12:59:56 -07:00
Linus Torvalds
bbec2a2dc3 More power management updates for 5.7-rc1
Rework compat ioctl handling in the user space hibernation
 interface (Christoph Hellwig) and fix a typo in a function
 name in the cpuidle haltpoll driver (Yihao Wu).
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCAAwFiEE4fcc61cGeeHD/fCwgsRv/nhiVHEFAl6QPXkSHHJqd0Byand5
 c29ja2kubmV0AAoJEILEb/54YlRx918P+NU9lM++pMi2Ng4wHmtRtHW9mH4M6L54
 /LTjDNZ4IE/v6JlK6hzaFUAhrFViI23gmUat8a7TT/o1NUsPS0QHxatFK+nGbjEk
 blB/rBHWpC5vGo8SZbqmvI0hbRn0Q6Ah5I+iV+KAk9Z76mDEMNHZKpP2CfiqSVQE
 QYsUIJOSUo/CMT1SZRE/xDrvoU418Y1Ed6a6Kn9Ki5uXvqDTPHoAyETZ9M6tLphP
 kGBpbnbkHx3FyYZ3EyjVEd8O6cDsxS2gIWu6YUCB31N4G7v3bJ6rfgperTCN999J
 8eQY9rNVlaAWIP9t0ObC3xOpoaNUcZC+V+yaHev3LU/6LP4Sued8cNBxQn26/RWN
 vyM5M6K0OphjPll9QfVfZFRUcuoBMyAtgVYw8mwT64GVJt3ukbd2QYDQHORXBQEC
 ziTtfLQEuAiUw/DRoTGo2XYDTlnd2nu9mFoTRU6juOawOwgwPbQldOtSJiMtCDoR
 cyaQH/t528w10jGCa+mIJZToTIet+gN6ui83M3kQdxMTa5ulgPClU8Kujn1wPgKX
 6jFrf+NJ6SNm6A/EhPk9t/soe7hhzyGwqx351aMQpZGX6UH4hQQPXgC0tyZ71Uj5
 UJ7Ys5RHcXg4kub/FJsfhv/3wdSPiekwe+U89UCQY5lxXC2x3iVjp50B4auCjW23
 tQVHpAvegWg=
 =h4ud
 -----END PGP SIGNATURE-----

Merge tag 'pm-5.7-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more power management updates from Rafael Wysocki:
 "Rework compat ioctl handling in the user space hibernation interface
  (Christoph Hellwig) and fix a typo in a function name in the cpuidle
  haltpoll driver (Yihao Wu)"

* tag 'pm-5.7-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpuidle-haltpoll: Fix small typo
  PM / sleep: handle the compat case in snapshot_set_swap_area()
  PM / sleep: move SNAPSHOT_SET_SWAP_AREA handling into a helper
2020-04-10 09:50:00 -07:00
David S. Miller
40fc7ad2c8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2020-04-10

The following pull-request contains BPF updates for your *net* tree.

We've added 13 non-merge commits during the last 7 day(s) which contain
a total of 13 files changed, 137 insertions(+), 43 deletions(-).

The main changes are:

1) JIT code emission fixes for riscv and arm32, from Luke Nelson and Xi Wang.

2) Disable vmlinux BTF info if GCC_PLUGIN_RANDSTRUCT is used, from Slava Bacherikov.

3) Fix oob write in AF_XDP when meta data is used, from Li RongQing.

4) Fix bpf_get_link_xdp_id() handling on single prog when flags are specified,
   from Andrey Ignatov.

5) Fix sk_assign() BPF helper for request sockets that can have sk_reuseport
   field uninitialized, from Joe Stringer.

6) Fix mprotect() test case for the BPF LSM, from KP Singh.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-09 17:39:22 -07:00
Linus Torvalds
c0cc271173 Modules updates for v5.7
Summary of modules changes for the 5.7 merge window:
 
 - Trivial zero-length array to flexible-array cleanup
 
 Signed-off-by: Jessica Yu <jeyu@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEVrp26glSWYuDNrCUwEV+OM47wXIFAl6O4MsQHGpleXVAa2Vy
 bmVsLm9yZwAKCRDARX44zjvBci4aEACsoeVA9rJGsYR7Z08xq9VF5/mPI9oFsXHQ
 HBnSr8QzOqpKBpAoE0Pp5WqhgbC0+5HrhcbMqE8yGHs+WJ7EDvKB8l8AF6OerRVq
 kmMlxYJwCJ7rJnnn6K8By4Q/13ZeCSgJfz8v8KJsqLADfm81L5/fGKvt4BThdyap
 fCuwv4fo0zq7JeEekCyvjaYfcqLHT6OpbOrkR9XQW6U2XTPC5nPFvmKwJvhTED/n
 18HVGRGxrfsPLcTkd/njPEEZetngKICTK6iRJk0ePH2cdxiNAPEInI/BZFOXge8H
 wo9l6UEGSlX1DicdokCc27SQLzd4R78xykT+Z1CrFZo+6INpY5F/+J2LNnknqP25
 BGqRpOu6HJZcpOUNTGaBk2c0BmXzKQzqCE3bq2ClI8ifVjwAqQrODbtie9eIqr/w
 5Ocg1np0z9F2NFjIiJjD288zASmBpnfgpwgkOsiQAGW8j6Xd40mzqH/Vu6/iT856
 +XC3FJvossm2XlB5D+koyWDYPtTQf1LbGt3DhCZ/5Xd7dFIRt51g8jxBJEWAyTJy
 EVxAohtEM9UTyqn9VymwUUrLPGV6JCG1dbfz+02KuqRklM59ZJQdKypv0vxhqdcv
 HS9N77xALC6AUdSupOIZiw+jSHNE2WgkDkdtJ6fS2JO2veqJcyLBEflMikT3+1l7
 PXji6Pt+9Q==
 =HWeX
 -----END PGP SIGNATURE-----

Merge tag 'modules-for-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux

Pull module updates from Jessica Yu:
 "Only a small cleanup this time around: a trivial conversion of
  zero-length arrays to flexible arrays"

* tag 'modules-for-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  kernel: module: Replace zero-length array with flexible-array member
2020-04-09 12:52:34 -07:00
Eric W. Biederman
63f818f46a proc: Use a dedicated lock in struct pid
syzbot wrote:
> ========================================================
> WARNING: possible irq lock inversion dependency detected
> 5.6.0-syzkaller #0 Not tainted
> --------------------------------------------------------
> swapper/1/0 just changed the state of lock:
> ffffffff898090d8 (tasklist_lock){.+.?}-{2:2}, at: send_sigurg+0x9f/0x320 fs/fcntl.c:840
> but this lock took another, SOFTIRQ-unsafe lock in the past:
>  (&pid->wait_pidfd){+.+.}-{2:2}
>
>
> and interrupts could create inverse lock ordering between them.
>
>
> other info that might help us debug this:
>  Possible interrupt unsafe locking scenario:
>
>        CPU0                    CPU1
>        ----                    ----
>   lock(&pid->wait_pidfd);
>                                local_irq_disable();
>                                lock(tasklist_lock);
>                                lock(&pid->wait_pidfd);
>   <Interrupt>
>     lock(tasklist_lock);
>
>  *** DEADLOCK ***
>
> 4 locks held by swapper/1/0:

The problem is that because wait_pidfd.lock is taken under the tasklist
lock.  It must always be taken with irqs disabled as tasklist_lock can be
taken from interrupt context and if wait_pidfd.lock was already taken this
would create a lock order inversion.

Oleg suggested just disabling irqs where I have added extra calls to
wait_pidfd.lock.  That should be safe and I think the code will eventually
do that.  It was rightly pointed out by Christian that sharing the
wait_pidfd.lock was a premature optimization.

It is also true that my pre-merge window testing was insufficient.  So
remove the premature optimization and give struct pid a dedicated lock of
it's own for struct pid things.  I have verified that lockdep sees all 3
paths where we take the new pid->lock and lockdep does not complain.

It is my current day dream that one day pid->lock can be used to guard the
task lists as well and then the tasklist_lock won't need to be held to
deliver signals.  That will require taking pid->lock with irqs disabled.

Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/lkml/00000000000011d66805a25cd73f@google.com/
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Reported-by: syzbot+343f75cdeea091340956@syzkaller.appspotmail.com
Reported-by: syzbot+832aabf700bc3ec920b9@syzkaller.appspotmail.com
Reported-by: syzbot+f675f964019f884dbd0f@syzkaller.appspotmail.com
Reported-by: syzbot+a9fb1457d720a55d6dc5@syzkaller.appspotmail.com
Fixes: 7bc3e6e55a ("proc: Use a list of inodes to flush from proc")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2020-04-09 12:15:35 -05:00
Grygorii Strashko
9bb50ed747 dma-debug: fix displaying of dma allocation type
The commit 2e05ea5cdc ("dma-mapping: implement dma_map_single_attrs using
dma_map_page_attrs") removed "dma_debug_page" enum, but missed to update
type2name string table. This causes incorrect displaying of dma allocation
type.
Fix it by removing "page" string from type2name string table and switch to
use named initializers.

Before (dma_alloc_coherent()):
k3-ringacc 4b800000.ringacc: scather-gather idx 2208 P=d1140000 N=d114 D=d1140000 L=40 DMA_BIDIRECTIONAL dma map error check not applicable
k3-ringacc 4b800000.ringacc: scather-gather idx 2216 P=d1150000 N=d115 D=d1150000 L=40 DMA_BIDIRECTIONAL dma map error check not applicable

After:
k3-ringacc 4b800000.ringacc: coherent idx 2208 P=d1140000 N=d114 D=d1140000 L=40 DMA_BIDIRECTIONAL dma map error check not applicable
k3-ringacc 4b800000.ringacc: coherent idx 2216 P=d1150000 N=d115 D=d1150000 L=40 DMA_BIDIRECTIONAL dma map error check not applicable

Fixes: 2e05ea5cdc ("dma-mapping: implement dma_map_single_attrs using dma_map_page_attrs")
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-04-08 21:46:57 +02:00
Kishon Vijay Abraham I
cdcda0d1f8 dma-direct: fix data truncation in dma_direct_get_required_mask()
The upper 32-bit physical address gets truncated inadvertently
when dma_direct_get_required_mask() invokes phys_to_dma_direct().
This results in dma_addressing_limited() return incorrect value
when used in platforms with LPAE enabled.
Fix it here by explicitly type casting 'max_pfn' to phys_addr_t
in order to prevent overflow of intermediate value while evaluating
'(max_pfn - 1) << PAGE_SHIFT'.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-04-08 20:52:24 +02:00
Peter Zijlstra
9a019db0b6 locking/lockdep: Improve 'invalid wait context' splat
The 'invalid wait context' splat doesn't print all the information
required to reconstruct / validate the error, specifically the
irq-context state is missing.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-04-08 12:05:07 +02:00
Qian Cai
d22cc7f67d locking/percpu-rwsem: Fix a task_struct refcount
The following commit:

  7f26482a87 ("locking/percpu-rwsem: Remove the embedded rwsem")

introduced task_struct memory leaks due to messing up the task_struct
refcount.

At the beginning of percpu_rwsem_wake_function(), it calls get_task_struct(),
but if the trylock failed, it will remain in the waitqueue. However, it
will run percpu_rwsem_wake_function() again with get_task_struct() to
increase the refcount but then only call put_task_struct() once the trylock
succeeded.

Fix it by adjusting percpu_rwsem_wake_function() a bit to guard against
when percpu_rwsem_wait() observing !private, terminating the wait and
doing a quick exit() while percpu_rwsem_wake_function() then doing
wake_up_process(p) as a use-after-free.

Fixes: 7f26482a87 ("locking/percpu-rwsem: Remove the embedded rwsem")
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200330213002.2374-1-cai@lca.pw
2020-04-08 12:05:06 +02:00
Valentin Schneider
96e74ebf8d sched/debug: Add task uclamp values to SCHED_DEBUG procfs
Requested and effective uclamp values can be a bit tricky to decipher when
playing with cgroup hierarchies. Add them to a task's procfs when
SCHED_DEBUG is enabled.

Reviewed-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200226124543.31986-4-valentin.schneider@arm.com
2020-04-08 11:35:27 +02:00
Valentin Schneider
9e3bf9469c sched/debug: Factor out printing formats into common macros
The printing macros in debug.c keep redefining the same output
format. Collect each output format in a single definition, and reuse that
definition in the other macros. While at it, add a layer of parentheses and
replace printf's  with the newly introduced macros.

Reviewed-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200226124543.31986-3-valentin.schneider@arm.com
2020-04-08 11:35:26 +02:00
Valentin Schneider
c745a6212c sched/debug: Remove redundant macro define
Most printing macros for procfs are defined globally in debug.c, and they
are re-defined (to the exact same thing) within proc_sched_show_task().

Get rid of the duplicate defines.

Reviewed-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200226124543.31986-2-valentin.schneider@arm.com
2020-04-08 11:35:24 +02:00
Vincent Donnefort
275b2f6723 sched/core: Remove unused rq::last_load_update_tick
The following commit:

  5e83eafbfd ("sched/fair: Remove the rq->cpu_load[] update code")

eliminated the last use case for rq->last_load_update_tick, so remove
the field as well.

Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Vincent Donnefort <vincent.donnefort@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/1584710495-308969-1-git-send-email-vincent.donnefort@arm.com
2020-04-08 11:35:23 +02:00
Sebastian Andrzej Siewior
62849a9612 workqueue: Remove the warning in wq_worker_sleeping()
The kernel test robot triggered a warning with the following race:
   task-ctx A                            interrupt-ctx B
 worker
  -> process_one_work()
    -> work_item()
      -> schedule();
         -> sched_submit_work()
           -> wq_worker_sleeping()
             -> ->sleeping = 1
               atomic_dec_and_test(nr_running)
         __schedule();                *interrupt*
                                       async_page_fault()
                                       -> local_irq_enable();
                                       -> schedule();
                                          -> sched_submit_work()
                                            -> wq_worker_sleeping()
                                               -> if (WARN_ON(->sleeping)) return
                                          -> __schedule()
                                            ->  sched_update_worker()
                                              -> wq_worker_running()
                                                 -> atomic_inc(nr_running);
                                                 -> ->sleeping = 0;

      ->  sched_update_worker()
        -> wq_worker_running()
          if (!->sleeping) return

In this context the warning is pointless everything is fine.
An interrupt before wq_worker_sleeping() will perform the ->sleeping
assignment (0 -> 1 > 0) twice.
An interrupt after wq_worker_sleeping() will trigger the warning and
nr_running will be decremented (by A) and incremented once (only by B, A
will skip it). This is the case until the ->sleeping is zeroed again in
wq_worker_running().

Remove the WARN statement because this condition may happen. Document
that preemption around wq_worker_sleeping() needs to be disabled to
protect ->sleeping and not just as an optimisation.

Fixes: 6d25be5782 ("sched/core, workqueues: Distangle worker accounting from rq lock")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Link: https://lkml.kernel.org/r/20200327074308.GY11705@shao2-debian
2020-04-08 11:35:20 +02:00
Aubrey Li
111688ca1c sched/fair: Fix negative imbalance in imbalance calculation
A negative imbalance value was observed after imbalance calculation,
this happens when the local sched group type is group_fully_busy,
and the average load of local group is greater than the selected
busiest group. Fix this problem by comparing the average load of the
local and busiest group before imbalance calculation formula.

Suggested-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Phil Auld <pauld@redhat.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Aubrey Li <aubrey.li@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/1585201349-70192-1-git-send-email-aubrey.li@intel.com
2020-04-08 11:35:20 +02:00
Huaixin Chang
26a8b12747 sched/fair: Fix race between runtime distribution and assignment
Currently, there is a potential race between distribute_cfs_runtime()
and assign_cfs_rq_runtime(). Race happens when cfs_b->runtime is read,
distributes without holding lock and finds out there is not enough
runtime to charge against after distribution. Because
assign_cfs_rq_runtime() might be called during distribution, and use
cfs_b->runtime at the same time.

Fibtest is the tool to test this race. Assume all gcfs_rq is throttled
and cfs period timer runs, slow threads might run and sleep, returning
unused cfs_rq runtime and keeping min_cfs_rq_runtime in their local
pool. If all this happens sufficiently quickly, cfs_b->runtime will drop
a lot. If runtime distributed is large too, over-use of runtime happens.

A runtime over-using by about 70 percent of quota is seen when we
test fibtest on a 96-core machine. We run fibtest with 1 fast thread and
95 slow threads in test group, configure 10ms quota for this group and
see the CPU usage of fibtest is 17.0%, which is far more than the
expected 10%.

On a smaller machine with 32 cores, we also run fibtest with 96
threads. CPU usage is more than 12%, which is also more than expected
10%. This shows that on similar workloads, this race do affect CPU
bandwidth control.

Solve this by holding lock inside distribute_cfs_runtime().

Fixes: c06f04c704 ("sched: Fix potential near-infinite distribute_cfs_runtime() loop")
Reviewed-by: Ben Segall <bsegall@google.com>
Signed-off-by: Huaixin Chang <changhuaixin@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/lkml/20200325092602.22471-1-changhuaixin@linux.alibaba.com/
2020-04-08 11:35:19 +02:00
Valentin Schneider
d76343c6b2 sched/fair: Align rq->avg_idle and rq->avg_scan_cost
sched/core.c uses update_avg() for rq->avg_idle and sched/fair.c uses an
open-coded version (with the exact same decay factor) for
rq->avg_scan_cost. On top of that, select_idle_cpu() expects to be able to
compare these two fields.

The only difference between the two is that rq->avg_scan_cost is computed
using a pure division rather than a shift. Turns out it actually matters,
first of all because the shifted value can be negative, and the standard
has this to say about it:

  """
  The result of E1 >> E2 is E1 right-shifted E2 bit positions. [...] If E1
  has a signed type and a negative value, the resulting value is
  implementation-defined.
  """

Not only this, but (arithmetic) right shifting a negative value (using 2's
complement) is *not* equivalent to dividing it by the corresponding power
of 2. Let's look at a few examples:

  -4      -> 0xF..FC
  -4 >> 3 -> 0xF..FF == -1 != -4 / 8

  -8      -> 0xF..F8
  -8 >> 3 -> 0xF..FF == -1 == -8 / 8

  -9      -> 0xF..F7
  -9 >> 3 -> 0xF..FE == -2 != -9 / 8

Make update_avg() use a division, and export it to the private scheduler
header to reuse it where relevant. Note that this still lets compilers use
a shift here, but should prevent any unwanted surprise. The disassembly of
select_idle_cpu() remains unchanged on arm64, and ttwu_do_wakeup() gains 2
instructions; the diff sort of looks like this:

  - sub x1, x1, x0
  + subs x1, x1, x0 // set condition codes
  + add x0, x1, #0x7
  + csel x0, x0, x1, mi // x0 = x1 < 0 ? x0 : x1
    add x0, x3, x0, asr #3

which does the right thing (i.e. gives us the expected result while still
using an arithmetic shift)

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200330090127.16294-1-valentin.schneider@arm.com
2020-04-08 11:35:18 +02:00
Jiri Olsa
d3296fb372 perf/core: Disable page faults when getting phys address
We hit following warning when running tests on kernel
compiled with CONFIG_DEBUG_ATOMIC_SLEEP=y:

 WARNING: CPU: 19 PID: 4472 at mm/gup.c:2381 __get_user_pages_fast+0x1a4/0x200
 CPU: 19 PID: 4472 Comm: dummy Not tainted 5.6.0-rc6+ #3
 RIP: 0010:__get_user_pages_fast+0x1a4/0x200
 ...
 Call Trace:
  perf_prepare_sample+0xff1/0x1d90
  perf_event_output_forward+0xe8/0x210
  __perf_event_overflow+0x11a/0x310
  __intel_pmu_pebs_event+0x657/0x850
  intel_pmu_drain_pebs_nhm+0x7de/0x11d0
  handle_pmi_common+0x1b2/0x650
  intel_pmu_handle_irq+0x17b/0x370
  perf_event_nmi_handler+0x40/0x60
  nmi_handle+0x192/0x590
  default_do_nmi+0x6d/0x150
  do_nmi+0x2f9/0x3c0
  nmi+0x8e/0xd7

While __get_user_pages_fast() is IRQ-safe, it calls access_ok(),
which warns on:

  WARN_ON_ONCE(!in_task() && !pagefault_disabled())

Peter suggested disabling page faults around __get_user_pages_fast(),
which gets rid of the warning in access_ok() call.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200407141427.3184722-1-jolsa@kernel.org
2020-04-08 11:33:46 +02:00
Ian Rogers
24fb6b8e7c perf/cgroup: Correct indirection in perf_less_group_idx()
The void* in perf_less_group_idx() is to a member in the array which points
at a perf_event*, as such it is a perf_event**.

Reported-By: John Sperbeck <jsperbeck@google.com>
Fixes: 6eef8a7116 ("perf/core: Use min_heap in visit_groups_merge()")
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200321164331.107337-1-irogers@google.com
2020-04-08 11:33:45 +02:00
Peter Zijlstra
33238c5045 perf/core: Fix event cgroup tracking
Song reports that installing cgroup events is broken since:

  db0503e4f6 ("perf/core: Optimize perf_install_in_event()")

The problem being that cgroup events try to track cpuctx->cgrp even
for disabled events, which is pointless and actively harmful since the
above commit. Rework the code to have explicit enable/disable hooks
for cgroup events, such that we can limit cgroup tracking to active
events.

More specifically, since the above commit disabled events are no
longer added to their context from the 'right' CPU, and we can't
access things like the current cgroup for a remote CPU.

Cc: <stable@vger.kernel.org> # v5.5+
Fixes: db0503e4f6 ("perf/core: Optimize perf_install_in_event()")
Reported-by: Song Liu <songliubraving@fb.com>
Tested-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200318193337.GB20760@hirez.programming.kicks-ass.net
2020-04-08 11:33:44 +02:00