Repository files (latest commit first)

Filename	Latest commit message	Latest commit date
Steven Rostedt (Red Hat) a9ce7c36aa tracing: Fix race of function probes counting ... The function probe counting for traceon and traceoff suffered a race condition where if the probe was executing on two or more CPUs at the same time, it could decrement the counter by more than one when disabling (or enabling) the tracer only once. The way the traceon and traceoff probes are suppose to work is that they disable (or enable) tracing once per count. If a user were to echo 'schedule:traceoff:3' into set_ftrace_filter, then when the schedule function was called, it would disable tracing. But the count should only be decremented once (to 2). Then if the user enabled tracing again (via tracing_on file), the next call to schedule would disable tracing again and the count would be decremented to 1. But if multiple CPUS called schedule at the same time, it is possible that the count would be decremented more than once because of the simple "count--" used. By reading the count into a local variable and using memory barriers we can guarantee that the count would only be decremented once per disable (or enable). The stack trace probe had a similar race, but here the stack trace will decrement for each time it is called. But this had the read-modify- write race, where it could stack trace more than the number of times that was specified. This case we use a cmpxchg to stack trace only the number of times specified. The dump probes can still use the old "update_count()" function as they only run once, and that is controlled by the dump logic itself. Link: http://lkml.kernel.org/r/20141118134643.4b550ee4@gandalf.local.home Signed-off-by: Steven Rostedt <rostedt@goodmis.org>		2014-11-18 23:06:35 -05:00
..
bpf	bpf: add search pruning optimization to verifier	2014-10-01 21:30:33 -04:00
configs	x86: Add "make tinyconfig" to configure the tiniest possible kernel	2014-08-08 16:30:24 -07:00
debug	kdb: replace strnicmp with strncasecmp	2014-10-14 02:18:25 +02:00
events	Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2014-10-15 07:48:18 +02:00
gcov	ARM: 8153/1: Enable gcov support on the ARM architecture	2014-09-26 14:39:57 +01:00
irq	Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2014-10-15 07:48:18 +02:00
locking	Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2014-10-13 15:51:40 +02:00
power	Merge branch 'pm-domains'	2014-10-07 01:18:12 +02:00
printk	Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2014-10-15 07:48:18 +02:00
rcu	rcu: Eliminate deadlock between CPU hotplug and expedited grace periods	2014-09-18 16:22:27 -07:00
sched	Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2014-10-15 07:48:18 +02:00
time	Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2014-10-15 07:48:18 +02:00
trace	tracing: Fix race of function probes counting	2014-11-18 23:06:35 -05:00
.gitignore
acct.c	acct: eliminate compile warning	2014-10-09 22:26:04 -04:00
async.c	kernel/async.c: switch to pr_foo()	2014-10-09 22:26:04 -04:00
audit.c	Merge git://git.infradead.org/users/eparis/audit	2014-10-19 16:25:56 -07:00
audit.h	audit: reduce scope of audit_log_fcaps	2014-09-23 16:37:51 -04:00
audit_tree.c	audit: rename audit_log_remove_rule to disambiguate for trees	2014-10-10 15:30:25 -04:00
audit_watch.c	audit: invalid op= values for rules	2014-09-23 16:37:53 -04:00
auditfilter.c	Merge git://git.infradead.org/users/eparis/audit	2014-10-19 16:25:56 -07:00
auditsc.c	Merge git://git.infradead.org/users/eparis/audit	2014-10-19 16:25:56 -07:00
backtracetest.c
bounds.c	page-cgroup: get rid of NR_PCG_FLAGS	2014-08-08 15:57:18 -07:00
capability.c
cgroup.c	Merge branch 'for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2014-10-10 07:26:02 -04:00
cgroup_freezer.c
compat.c	compat: nanosleep: Clarify error handling	2014-09-06 12:58:18 +02:00
configs.c
context_tracking.c
cpu.c	rcu: Eliminate deadlock between CPU hotplug and expedited grace periods	2014-09-18 16:22:27 -07:00
cpu_pm.c
cpuset.c	Merge branch 'for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup	2014-10-10 07:24:40 -04:00
crash_dump.c	crash_dump: Make is_kdump_kernel() accessible from modules	2014-08-25 15:42:19 -07:00
cred.c
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	2014-10-13 16:23:15 +02:00
extable.c
fork.c	Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2014-10-13 16:23:15 +02:00
freezer.c
futex.c	futex: Ensure get_futex_key_refs() always implies a barrier	2014-10-18 09:28:51 -07:00
futex_compat.c
groups.c
hung_task.c
irq_work.c	Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2014-10-15 07:48:18 +02:00
jump_label.c
kallsyms.c	kernel/kallsyms.c: use __seq_open_private()	2014-10-14 02:18:16 +02:00
kcmp.c	kcmp: fix standard comparison bug	2014-09-10 15:42:12 -07:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec.c	kexec: remove the unused function parameter	2014-10-14 02:18:21 +02:00
kmod.c
kprobes.c	kprobes: Skip kretprobe hit in NMI context to avoid deadlock	2014-08-08 10:38:04 +02:00
ksysfs.c
kthread.c	kernel/kthread.c: partial revert of 81c98869fa ("kthread: ensure locality of task_struct allocations")	2014-10-09 22:25:51 -04:00
latencytop.c
Makefile	bin2c: move bin2c in scripts/basic	2014-08-08 15:57:32 -07:00
module-internal.h
module.c	A single panic fix for a rare race, stable CC'd.	2014-10-18 10:24:26 -07:00
module_signing.c
notifier.c
nsproxy.c
padata.c
panic.c	panic: add TAINT_SOFTLOCKUP	2014-08-08 15:57:24 -07:00
params.c	kernel/param: consolidate __{start,stop}___param[] in <linux/moduleparam.h>	2014-10-14 02:18:28 +02:00
pid.c
pid_namespace.c
profile.c
ptrace.c
range.c
reboot.c	kernel: add support for kernel restart handler call chain	2014-09-26 00:00:06 -07:00
relay.c
res_counter.c
resource.c	x86: optimize resource lookups for ioremap	2014-10-14 02:18:22 +02:00
seccomp.c	Merge branch 'x86-seccomp-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2014-10-14 02:27:06 +02:00
signal.c	Merge branch 'signal-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc	2014-08-09 09:58:12 -07:00
smp.c	Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2014-10-15 07:48:18 +02:00
smpboot.c
smpboot.h
softirq.c	Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2014-10-15 07:48:18 +02:00
stacktrace.c
stop_machine.c
sys.c	Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2014-10-13 16:23:15 +02:00
sys_ni.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next	2014-10-08 21:40:54 -04:00
sysctl.c	Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2014-10-13 15:44:12 +02:00
sysctl_binary.c	dmaengine-3.17	2014-10-07 20:39:25 -04:00
system_certificates.S
system_keyring.c
task_work.c
taskstats.c	scheduler: Replace __get_cpu_var with this_cpu_ptr	2014-08-26 13:45:45 -04:00
test_kprobes.c	kernel/test_kprobes.c: use current logging functions	2014-08-08 15:57:18 -07:00
torture.c	torture: Address race in module cleanup	2014-09-16 13:41:06 -07:00
tracepoint.c
tsacct.c
uid16.c
up.c
user-return-notifier.c	scheduler: Replace __get_cpu_var with this_cpu_ptr	2014-08-26 13:45:45 -04:00
user.c
user_namespace.c	proc: constify seq_operations	2014-08-08 15:57:22 -07:00
utsname.c
utsname_sysctl.c
watchdog.c	Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2014-10-15 07:48:18 +02:00
workqueue.c	workqueue: Use cond_resched_rcu_qs macro	2014-10-06 05:58:26 -07:00
workqueue_internal.h