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Juri Lelli ecda2b66e2 sched/deadline: Fix missing clock update
A missing clock update is causing the following warning:

 rq->clock_update_flags < RQCF_ACT_SKIP
 WARNING: CPU: 10 PID: 0 at kernel/sched/sched.h:963 inactive_task_timer+0x5d6/0x720
 Call Trace:
  <IRQ>
  __hrtimer_run_queues+0x10f/0x530
  hrtimer_interrupt+0xe5/0x240
  smp_apic_timer_interrupt+0x79/0x2b0
  apic_timer_interrupt+0xf/0x20
  </IRQ>
  do_idle+0x203/0x280
  cpu_startup_entry+0x6f/0x80
  start_secondary+0x1b0/0x200
  secondary_startup_64+0xa5/0xb0
 hardirqs last  enabled at (793919): [<ffffffffa27c5f6e>] cpuidle_enter_state+0x9e/0x360
 hardirqs last disabled at (793920): [<ffffffffa2a0096e>] interrupt_entry+0xce/0xe0
 softirqs last  enabled at (793922): [<ffffffffa20bef78>] irq_enter+0x68/0x70
 softirqs last disabled at (793921): [<ffffffffa20bef5d>] irq_enter+0x4d/0x70

This happens because inactive_task_timer() calls sub_running_bw() (if
TASK_DEAD and non_contending) that might trigger a schedutil update,
which might access the clock. Clock is however currently updated only
later in inactive_task_timer() function.

Fix the problem by updating the clock right after task_rq_lock().

Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Claudio Scordino <claudio@evidence.eu.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luca Abeni <luca.abeni@santannapisa.it>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180530160809.9074-1-juri.lelli@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-31 12:27:13 +02:00
arch nds32 patches for 4.17 2018-05-28 05:25:57 -07:00
block blk-mq: fix sysfs inflight counter 2018-04-26 09:02:01 -06:00
certs
crypto crypto: drbg - set freed buffers to NULL 2018-04-21 00:57:00 +08:00
Documentation Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-05-25 19:54:42 -07:00
drivers ARM: SoC fixes for 4.17-rc 2018-05-26 14:05:16 -07:00
firmware
fs proc: fix smaps and meminfo alignment 2018-05-25 18:12:11 -07:00
include Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-05-26 13:10:16 -07:00
init init/main.c: include <linux/mem_encrypt.h> 2018-05-25 18:12:11 -07:00
ipc ipc/shm: fix shmat() nil address after round-down when remapping 2018-05-25 18:12:11 -07:00
kernel sched/deadline: Fix missing clock update 2018-05-31 12:27:13 +02:00
lib idr: fix invalid ptr dereference on item delete 2018-05-25 18:12:10 -07:00
LICENSES
mm kasan: fix memory hotplug during boot 2018-05-25 18:12:11 -07:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-05-25 19:54:42 -07:00
samples x86/cpufeature: Guard asm_volatile_goto usage for BPF compilation 2018-05-13 21:49:14 +02:00
scripts checkpatch: fix macro argument precedence test 2018-05-25 18:12:11 -07:00
security Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-05-21 11:54:57 -07:00
sound ALSA: hda - Fix runtime PM 2018-05-24 20:16:47 +02:00
tools Merge branch 'akpm' (patches from Andrew) 2018-05-25 20:24:28 -07:00
usr
virt KVM: arm/arm64: VGIC/ITS save/restore: protect kvm_read_guest() calls 2018-05-15 13:36:53 +02:00
.clang-format clang-format: add configuration file 2018-04-11 10:28:35 -07:00
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap Merge candidates for 4.17 merge window 2018-04-06 17:35:43 -07:00
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS Merge branch 'akpm' (patches from Andrew) 2018-05-25 20:24:28 -07:00
Makefile Linux 4.17-rc7 2018-05-27 13:01:47 -07:00
README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.