John Stultz 4eca11dbd2 timekeeping: Avoid taking lock in NMI path with CONFIG_DEBUG_TIMEKEEPING ...

commit 27727df240 upstream.

When I added some extra sanity checking in timekeeping_get_ns() under
CONFIG_DEBUG_TIMEKEEPING, I missed that the NMI safe __ktime_get_fast_ns()
method was using timekeeping_get_ns().

Thus the locking added to the debug checks broke the NMI-safety of
__ktime_get_fast_ns().

This patch open-codes the timekeeping_get_ns() logic for
__ktime_get_fast_ns(), so can avoid any deadlocks in NMI.

Fixes: 4ca22c2648 "timekeeping: Add warnings when overflows or underflows are observed"
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/1471993702-29148-2-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2016-09-15 08:27:52 +02:00

..

bpf

bpf, inode: disallow userns mounts

2016-06-24 10:18:17 -07:00

configs

kconfig: add xenconfig defconfig helper

2015-06-16 11:04:29 +01:00

debug

…

events

bpf, perf: delay release of BPF prog after grace period

2016-07-11 09:31:11 -07:00

gcov

gcov: add support for GCC 5.1

2015-06-30 19:44:57 -07:00

irq

genirq/msi: Make sure PCI MSIs are activated early

2016-09-07 08:32:38 +02:00

livepatch

livepatch: x86: fix relocation computation with kASLR

2015-11-11 17:36:04 +01:00

locking

locking/qspinlock: Fix spin_unlock_wait() some more

2016-07-27 09:47:29 -07:00

power

PM / sleep: Clear pm_suspend_global_flags upon hibernate

2016-04-12 09:09:05 -07:00

printk

printk: do cond_resched() between lines while outputting to consoles

2016-02-17 12:30:57 -08:00

rcu

Merge branches 'doc.2015.10.06a', 'percpu-rwsem.2015.10.06a' and 'torture.2015.10.06a' into HEAD

2015-10-07 16:06:25 -07:00

sched

sched/numa: Fix use-after-free bug in the task_numa_compare

2016-09-15 08:27:45 +02:00

time

timekeeping: Avoid taking lock in NMI path with CONFIG_DEBUG_TIMEKEEPING

2016-09-15 08:27:52 +02:00

trace

tracing: Handle NULL formats in hold_module_trace_bprintk_format()

2016-07-27 09:47:32 -07:00

.gitignore

certs: add .gitignore to stop git nagging about x509_certificate_list

2015-10-21 15:18:35 +01:00

acct.c

acct: check FMODE_CAN_WRITE

2015-04-11 22:27:55 -04:00

async.c

…

audit_fsnotify.c

audit: clean simple fsnotify implementation

2015-08-06 16:14:53 -04:00

audit_tree.c

audit: audit_tree_match can be boolean

2015-11-04 08:23:51 -05:00

audit_watch.c

Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit

2015-09-08 13:34:59 -07:00

audit.c

mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd

2015-11-06 17:50:42 -08:00

audit.h

audit: audit_tree_match can be boolean

2015-11-04 08:23:51 -05:00

auditfilter.c

audit: fix comment block whitespace

2015-11-04 08:23:51 -05:00

auditsc.c

audit: fix a double fetch in audit_log_single_execve_arg()

2016-08-20 18:09:22 +02:00

backtracetest.c

…

bounds.c

…

capability.c

kernel: Add noaudit variant of ns_capable()

2016-09-15 08:27:50 +02:00

cgroup_freezer.c

cgroup: fix handling of multi-destination migration from subtree_control enabling

2015-12-03 10:18:21 -05:00

cgroup_pids.c

cgroup_pids: don't account for the root cgroup

2015-12-03 10:18:21 -05:00

cgroup.c

cgroup: set css->id to -1 during init

2016-08-10 11:49:27 +02:00

compat.c

compat: cleanup coding in compat_get_bitmap() and compat_put_bitmap()

2015-06-04 23:57:18 +02:00

configs.c

…

context_tracking.c

context_tracking: avoid irq_save/irq_restore on guest entry and exit

2015-11-10 12:06:23 +01:00

cpu_pm.c

kernel/cpu_pm: fix cpu_cluster_pm_exit comment

2015-09-03 02:42:20 +02:00

cpu.c

Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-11-03 18:03:50 -08:00

cpuset.c

cgroup, cpuset: replace cpuset_post_attach_flush() with cgroup_subsys->post_attach callback

2016-05-04 14:48:49 -07:00

crash_dump.c

…

cred.c

cred: Reject inodes with invalid ids in set_create_file_as()

2016-09-15 08:27:49 +02:00

delayacct.c

…

dma.c

…

elfcore.c

…

exec_domain.c

Remove rest of exec domains.

2015-04-12 21:03:31 +02:00

exit.c

wait/ptrace: assume __WALL if the child is traced

2016-06-07 18:14:35 -07:00

extable.c

kernel/extable.c: remove duplicated include

2015-09-10 13:29:01 -07:00

fork.c

cgroup: reduce read locked section of cgroup_threadgroup_rwsem during fork

2016-09-15 08:27:51 +02:00

freezer.c

…

futex_compat.c

ptrace: use fsuid, fsgid, effective creds for fs access checks

2016-02-25 12:01:16 -08:00

futex.c

futex: Acknowledge a new waiter in counter before plist

2016-05-04 14:48:43 -07:00

groups.c

kernel: conditionally support non-root users, groups and capabilities

2015-04-15 16:35:22 -07:00

hung_task.c

kernel/hung_task.c: change hung_task.c to use for_each_process_thread()

2015-04-15 16:35:22 -07:00

irq_work.c

treewide: Remove old email address

2015-11-23 09:44:58 +01:00

jump_label.c

locking/static_key: Fix concurrent static_key_slow_inc()

2016-07-27 09:47:29 -07:00

kallsyms.c

…

kcmp.c

ptrace: use fsuid, fsgid, effective creds for fs access checks

2016-02-25 12:01:16 -08:00

Kconfig.freezer

…

Kconfig.hz

…

Kconfig.locks

locking/qrwlock: Rename QUEUE_RWLOCK to QUEUED_RWLOCKS

2015-05-12 09:46:00 +02:00

Kconfig.preempt

…

kexec_core.c

kexec: use file name as the output message prefix

2015-11-06 17:50:42 -08:00

kexec_file.c

kexec: use file name as the output message prefix

2015-11-06 17:50:42 -08:00

kexec_internal.h

kexec: split kexec_file syscall code to kexec_file.c

2015-09-10 13:29:01 -07:00

kexec.c

kexec: use file name as the output message prefix

2015-11-06 17:50:42 -08:00

kmod.c

kmod: don't run async usermode helper as a child of kworker thread

2015-10-23 17:55:10 +09:00

kprobes.c

perf/x86/hw_breakpoints: Disallow kernel breakpoints unless kprobe-safe

2015-08-04 10:16:54 +02:00

ksysfs.c

kexec: split kexec_load syscall from kexec core code

2015-09-10 13:29:01 -07:00

kthread.c

kernel/kthread.c:kthread_create_on_node(): clarify documentation

2015-09-04 16:54:41 -07:00

latencytop.c

…

Makefile

sys_membarrier(): system-wide memory barrier (generic, x86)

2015-09-11 15:21:34 -07:00

membarrier.c

sys_membarrier(): system-wide memory barrier (generic, x86)

2015-09-11 15:21:34 -07:00

memremap.c

devm_memremap: Fix error value when memremap failed

2016-03-03 15:07:08 -08:00

module_signing.c

KEYS: Merge the type-specific data with the payload data

2015-10-21 15:18:36 +01:00

module-internal.h

…

module.c

module: Invalidate signatures on force-loaded modules

2016-08-20 18:09:27 +02:00

notifier.c

Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-09-01 08:40:25 -07:00

nsproxy.c

…

padata.c

…

panic.c

printk: do cond_resched() between lines while outputting to consoles

2016-02-17 12:30:57 -08:00

params.c

Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

2015-11-09 15:53:39 -08:00

pid_namespace.c

…

pid.c

pidns: fix NULL dereference in __task_pid_nr_ns()

2015-11-24 12:03:55 -08:00

profile.c

mm: rename alloc_pages_exact_node() to __alloc_pages_node()

2015-09-08 15:35:28 -07:00

ptrace.c

ptrace: use fsuid, fsgid, effective creds for fs access checks

2016-02-25 12:01:16 -08:00

range.c

…

reboot.c

kexec: split kexec_load syscall from kexec core code

2015-09-10 13:29:01 -07:00

relay.c

kernel/relay.c: use kvfree() in relay_free_page_array()

2015-06-30 19:44:59 -07:00

resource.c

kernel/resource.c: fix muxed resource handling in __request_region()

2016-03-03 15:07:29 -08:00

seccomp.c

seccomp: always propagate NO_NEW_PRIVS on tsync

2016-03-03 15:07:25 -08:00

signal.c

kernel/signal.c: unexport sigsuspend()

2015-11-20 16:17:32 -08:00

smp.c

mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd

2015-11-06 17:50:42 -08:00

smpboot.c

stop_machine: Kill smp_hotplug_thread->pre_unpark, introduce stop_machine_unpark()

2015-10-20 10:23:55 +02:00

smpboot.h

…

softirq.c

…

stacktrace.c

…

stop_machine.c

kernel: remove stop_machine() Kconfig dependency

2015-12-12 10:15:34 -08:00

sys_ni.c

mm: mlock: add new mlock system call

2015-11-05 19:34:48 -08:00

sys.c

prctl: take mmap sem for writing to protect against others

2016-02-25 12:01:25 -08:00

sysctl_binary.c

fs/coredump: prevent fsuid=0 dumps into user-controlled directories

2016-04-12 09:08:58 -07:00

sysctl.c

pipe: limit the per-user amount of pages allocated in pipes

2016-06-07 18:14:35 -07:00

task_work.c

task_work: remove fifo ordering guarantee

2015-09-05 13:46:58 -07:00

taskstats.c

…

test_kprobes.c

…

torture.c

torture: Consolidate cond_resched_rcu_qs() into stutter_wait()

2015-10-06 11:25:01 -07:00

tracepoint.c

tracepoint: Give priority to probes of tracepoints

2015-10-25 21:33:54 -04:00

tsacct.c

…

uid16.c

…

up.c

…

user_namespace.c

capabilities: ambient capabilities

2015-09-04 16:54:41 -07:00

user-return-notifier.c

…

user.c

…

utsname_sysctl.c

…

utsname.c

…

watchdog.c

watchdog: don't run proc_watchdog_update if new value is same as old

2016-04-12 09:08:54 -07:00

workqueue_internal.h

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workqueue.c

workqueue: fix rebind bound workers warning

2016-05-18 17:06:50 -07:00