Peter Zijlstra 920c720aa5 locking/mcs: Fix mcs_spin_lock() ordering ...

Similar to commit b4b29f9485 ("locking/osq: Fix ordering of node
initialisation in osq_lock") the use of xchg_acquire() is
fundamentally broken with MCS like constructs.

Furthermore, it turns out we rely on the global transitivity of this
operation because the unlock path observes the pointer with a
READ_ONCE(), not an smp_load_acquire().

This is non-critical because the MCS code isn't actually used and
mostly serves as documentation, a stepping stone to the more complex
things we've build on top of the idea.

Reported-by: Andrea Parri <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Will Deacon <[email protected]>
Fixes: 3552a07a9c ("locking/mcs: Use acquire/release semantics")
Signed-off-by: Ingo Molnar <[email protected]>

2016-02-29 10:02:41 +01:00

..

bpf

bpf: fix branch offset adjustment on backjumps after patching ctx expansion

2016-02-10 16:56:47 -05:00

configs

…

debug

module: use a structure to encapsulate layout.

2015-12-04 22:46:25 +01:00

events

perf: Robustify task_function_call()

2016-02-25 08:44:29 +01:00

gcov

gcov: use within_module() helper.

2015-12-04 22:46:25 +01:00

irq

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

2016-01-31 14:48:58 -08:00

livepatch

livepatch: Cleanup module page permission changes

2015-12-04 22:51:07 +01:00

locking

locking/mcs: Fix mcs_spin_lock() ordering

2016-02-29 10:02:41 +01:00

power

PM: APM_EMULATION does not depend on PM

2016-01-27 23:20:14 +01:00

printk

kernel: printk: specify alignment for struct printk_log

2016-01-20 17:09:18 -08:00

rcu

Merge branches 'doc.2015.12.05a', 'exp.2015.12.07a', 'fixes.2015.12.07a', 'list.2015.12.04b' and 'torture.2015.12.05a' into HEAD

2015-12-07 17:02:54 -08:00

sched

sched/deadline: Fix trivial typo in printk() message

2016-02-17 10:02:00 +01:00

time

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

2016-01-31 15:49:06 -08:00

trace

Merge tag 'trace-fixes-v4.5-rc5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2016-02-25 20:12:09 -08:00

.gitignore

certs: add .gitignore to stop git nagging about x509_certificate_list

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

acct.c

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async.c

async: export current_is_async()

2015-11-19 17:51:48 +01:00

audit_fsnotify.c

wrappers for ->i_mutex access

2016-01-22 18:04:28 -05:00

audit_tree.c

audit: audit_tree_match can be boolean

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

audit_watch.c

wrappers for ->i_mutex access

2016-01-22 18:04:28 -05:00

audit.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

2016-01-17 19:13:15 -08:00

audit.h

security: Make inode argument of inode_getsecid non-const

2015-12-24 11:09:39 -05:00

auditfilter.c

audit: fix comment block whitespace

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

auditsc.c

security: Make inode argument of inode_getsecid non-const

2015-12-24 11:09:39 -05:00

backtracetest.c

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bounds.c

…

capability.c

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cgroup_freezer.c

cgroup: kill cgrp_ss_priv[CGROUP_CANFORK_COUNT] and friends

2015-12-03 10:24:08 -05:00

cgroup_pids.c

cgroup_pids: fix a typo.

2015-12-14 14:54:37 -05:00

cgroup.c

cgroup: make sure a parent css isn't freed before its children

2016-01-22 10:42:58 -05:00

compat.c

…

configs.c

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context_tracking.c

context_tracking: Switch to new static_branch API

2015-11-24 09:56:43 +01:00

cpu_pm.c

kernel/cpu_pm: fix cpu_cluster_pm_exit comment

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

cpu.c

kernel/cpu.c: make set_cpu_* static inlines

2016-01-20 17:09:18 -08:00

cpuset.c

cpuset: make mm migration asynchronous

2016-01-22 10:22:46 -05:00

crash_dump.c

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cred.c

kmemcg: account certain kmem allocations to memcg

2016-01-14 16:00:49 -08:00

delayacct.c

kmemcg: account certain kmem allocations to memcg

2016-01-14 16:00:49 -08:00

dma.c

…

elfcore.c

…

exec_domain.c

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exit.c

exit: remove unneeded declaration of exit_mm()

2016-01-20 17:09:18 -08:00

extable.c

kernel/extable.c: remove duplicated include

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

fork.c

mm: rework virtual memory accounting

2016-01-14 16:00:49 -08:00

freezer.c

…

futex_compat.c

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

2016-01-20 17:09:18 -08:00

futex.c

futex: Remove requirement for lock_page() in get_futex_key()

2016-02-17 10:42:17 +01:00

groups.c

…

hung_task.c

…

irq_work.c

treewide: Remove old email address

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

jump_label.c

treewide: Remove old email address

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

kallsyms.c

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kcmp.c

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

2016-01-20 17:09:18 -08:00

Kconfig.freezer

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Kconfig.hz

…

Kconfig.locks

…

Kconfig.preempt

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kexec_core.c

kernel/kexec_core.c: use list_for_each_entry_safe in kimage_free_page_list

2016-01-20 17:09:18 -08:00

kexec_file.c

kexec: move some memembers and definitions within the scope of CONFIG_KEXEC_FILE

2016-01-20 17:09:18 -08:00

kexec_internal.h

kexec: move some memembers and definitions within the scope of CONFIG_KEXEC_FILE

2016-01-20 17:09:18 -08:00

kexec.c

kexec: set KEXEC_TYPE_CRASH before sanity_check_segment_list()

2016-01-20 17:09:18 -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

rcu: Remove TINY_RCU bloat from pointless boot parameters

2015-12-07 16:59:37 -08:00

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

Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

2016-02-25 18:54:53 -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

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module.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching

2016-02-18 16:34:15 -08:00

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

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padata.c

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panic.c

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

2016-01-16 11:17:25 -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

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pid.c

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

2016-01-31 15:44:04 -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

2016-01-20 17:09:18 -08:00

range.c

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reboot.c

kexec: split kexec_load syscall from kexec core code

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

relay.c

wrappers for ->i_mutex access

2016-01-22 18:04:28 -05:00

resource.c

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

2016-02-20 08:57:52 -08:00

seccomp.c

seccomp: always propagate NO_NEW_PRIVS on tsync

2016-01-27 07:38:25 -08:00

signal.c

signals: avoid random wakeups in sigsuspend()

2016-02-05 18:10:40 -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

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softirq.c

…

stacktrace.c

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stop_machine.c

kernel/stop_machine.c: remove CONFIG_SMP dependencies

2016-01-16 11:17:24 -08:00

sys_ni.c

vfs: add copy_file_range syscall and vfs helper

2015-12-01 14:00:53 -05:00

sys.c

prctl: take mmap sem for writing to protect against others

2016-01-20 17:09:18 -08:00

sysctl_binary.c

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sysctl.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2016-01-22 10:24:03 -08:00

task_work.c

task_work: remove fifo ordering guarantee

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

taskstats.c

…

test_kprobes.c

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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

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uid16.c

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up.c

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user_namespace.c

kernel/*: switch to memdup_user_nul()

2016-01-04 10:27:55 -05:00

user-return-notifier.c

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user.c

…

utsname_sysctl.c

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utsname.c

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watchdog.c

Merge branch 'for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

2016-01-11 18:53:13 -08:00

workqueue_internal.h

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workqueue.c

workqueue: handle NUMA_NO_NODE for unbound pool_workqueue lookup

2016-02-10 12:13:05 -05:00