Repository files (latest commit first)

Filename	Latest commit message	Latest commit date
Will Deacon b4b29f9485 locking/osq: Fix ordering of node initialisation in osq_lock ... The Cavium guys reported a soft lockup on their arm64 machine, caused by commit c55a6ffa62 ("locking/osq: Relax atomic semantics"): mutex_optimistic_spin+0x9c/0x1d0 __mutex_lock_slowpath+0x44/0x158 mutex_lock+0x54/0x58 kernfs_iop_permission+0x38/0x70 __inode_permission+0x88/0xd8 inode_permission+0x30/0x6c link_path_walk+0x68/0x4d4 path_openat+0xb4/0x2bc do_filp_open+0x74/0xd0 do_sys_open+0x14c/0x228 SyS_openat+0x3c/0x48 el0_svc_naked+0x24/0x28 This is because in osq_lock we initialise the node for the current CPU: node->locked = 0; node->next = NULL; node->cpu = curr; and then publish the current CPU in the lock tail: old = atomic_xchg_acquire(&lock->tail, curr); Once the update to lock->tail is visible to another CPU, the node is then live and can be both read and updated by concurrent lockers. Unfortunately, the ACQUIRE semantics of the xchg operation mean that there is no guarantee the contents of the node will be visible before lock tail is updated. This can lead to lock corruption when, for example, a concurrent locker races to set the next field. Fixes: c55a6ffa62 ("locking/osq: Relax atomic semantics"): Reported-by: David Daney <ddaney@caviumnetworks.com> Reported-by: Andrew Pinski <andrew.pinski@caviumnetworks.com> Tested-by: Andrew Pinski <andrew.pinski@caviumnetworks.com> Acked-by: Davidlohr Bueso <dave@stgolabs.net> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: http://lkml.kernel.org/r/1449856001-21177-1-git-send-email-will.deacon@arm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2015-12-17 11:40:29 -08:00
..
bpf	bpf: fix allocation warnings in bpf maps and integer overflow	2015-12-02 23:36:00 -05:00
configs
debug
events	Merge branch 'for-4.4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup	2015-12-08 13:35:52 -08:00
gcov
irq	Merge branches 'irq-urgent-for-linus' and 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-11-15 09:30:48 -08:00
livepatch	livepatch: x86: fix relocation computation with kASLR	2015-11-11 17:36:04 +01:00
locking	locking/osq: Fix ordering of node initialisation in osq_lock	2015-12-17 11:40:29 -08:00
power	mm, page_alloc: rename __GFP_WAIT to __GFP_RECLAIM	2015-11-06 17:50:42 -08:00
printk	printk: prevent userland from spoofing kernel messages	2015-11-06 17:50:42 -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/wait: Fix the signal handling fix	2015-12-13 14:30:59 -08:00
time	Merge branches 'irq-urgent-for-linus' and 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-11-15 09:30:48 -08:00
trace	Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-12-08 13:01:23 -08:00
.gitignore	certs: add .gitignore to stop git nagging about x509_certificate_list	2015-10-21 15:18:35 +01:00
acct.c
async.c
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
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
auditfilter.c	audit: fix comment block whitespace	2015-11-04 08:23:51 -05:00
auditsc.c	Merge branch 'upstream' of git://git.infradead.org/users/pcmoore/audit	2015-09-08 13:34:59 -07:00
backtracetest.c
bounds.c
capability.c
cgroup.c	cgroup: fix handling of multi-destination migration from subtree_control enabling	2015-12-03 10:18:21 -05:00
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
compat.c
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.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
cpu_pm.c	kernel/cpu_pm: fix cpu_cluster_pm_exit comment	2015-09-03 02:42:20 +02:00
cpuset.c	cgroup: fix handling of multi-destination migration from subtree_control enabling	2015-12-03 10:18:21 -05:00
crash_dump.c
cred.c	kernel/cred.c: remove unnecessary kdebug atomic reads	2015-09-10 13:29:01 -07:00
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.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
extable.c	kernel/extable.c: remove duplicated include	2015-09-10 13:29:01 -07:00
fork.c	cgroup: pids: fix race between cgroup_post_fork() and cgroup_migrate()	2015-11-30 09:48:18 -05:00
freezer.c
futex.c	driver core update for 4.4-rc1	2015-11-04 21:50:37 -08:00
futex_compat.c
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
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec.c	kexec: use file name as the output message prefix	2015-11-06 17:50:42 -08:00
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
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
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	libnvdimm for 4.4:	2015-11-10 12:07:22 -08:00
module-internal.h
module.c	module: Fix locking in symbol_put_addr()	2015-08-24 10:37:01 +09:30
module_signing.c	KEYS: Merge the type-specific data with the payload data	2015-10-21 15:18:36 +01:00
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	kernel/panic.c: turn off locks debug before releasing console lock	2015-11-20 16:17:32 -08:00
params.c	Nothing exciting, minor tweaks and cleanups.	2015-11-09 15:53:39 -08:00
pid.c	pidns: fix NULL dereference in __task_pid_nr_ns()	2015-11-24 12:03:55 -08:00
pid_namespace.c
profile.c	mm: rename alloc_pages_exact_node() to __alloc_pages_node()	2015-09-08 15:35:28 -07:00
ptrace.c	seccomp, ptrace: add support for dumping seccomp filters	2015-10-27 19:55:13 -07:00
range.c
reboot.c	kexec: split kexec_load syscall from kexec core code	2015-09-10 13:29:01 -07:00
relay.c
resource.c	mm: enhance region_is_ram() to region_intersects()	2015-08-10 23:07:05 -04:00
seccomp.c	seccomp, ptrace: add support for dumping seccomp filters	2015-10-27 19:55:13 -07:00
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.c	pidns: fix set/getpriority and ioprio_set/get in PRIO_USER mode	2015-11-06 17:50:42 -08:00
sys_ni.c	mm: mlock: add new mlock system call	2015-11-05 19:34:48 -08:00
sysctl.c	kernel/watchdog.c: add sysctl knob hardlockup_panic	2015-11-05 19:34:48 -08:00
sysctl_binary.c
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-return-notifier.c
user.c
user_namespace.c	capabilities: ambient capabilities	2015-09-04 16:54:41 -07:00
utsname.c
utsname_sysctl.c
watchdog.c	kernel/watchdog.c: fix race between proc_watchdog_thresh() and watchdog_timer_fn()	2015-11-05 19:34:48 -08:00
workqueue.c	Merge branch 'for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq	2015-11-05 14:16:27 -08:00
workqueue_internal.h