Steven Rostedt (Red Hat)
d4ecbfc49b
tracing: Fix stack tracer with fentry use
...
When gcc 4.6 on x86 is used, the function tracer will use the new
option -mfentry which does a call to "fentry" at every function
instead of "mcount". The significance of this is that fentry is
called as the first operation of the function instead of the mcount
usage of being called after the stack.
This causes the stack tracer to show some bogus results for the size
of the last function traced, as well as showing "ftrace_call" instead
of the function. This is due to the stack frame not being set up
by the function that is about to be traced.
# cat stack_trace
Depth Size Location (48 entries)
----- ---- --------
0) 4824 216 ftrace_call+0x5/0x2f
1) 4608 112 ____cache_alloc+0xb7/0x22d
2) 4496 80 kmem_cache_alloc+0x63/0x12f
The 216 size for ftrace_call includes both the ftrace_call stack
(which includes the saving of registers it does), as well as the
stack size of the parent.
To fix this, if CC_USING_FENTRY is defined, then the stack_tracer
will reserve the first item in stack_dump_trace[] array when
calling save_stack_trace(), and it will fill it in with the parent ip.
Then the code will look for the parent pointer on the stack and
give the real size of the parent's stack pointer:
# cat stack_trace
Depth Size Location (14 entries)
----- ---- --------
0) 2640 48 update_group_power+0x26/0x187
1) 2592 224 update_sd_lb_stats+0x2a5/0x4ac
2) 2368 160 find_busiest_group+0x31/0x1f1
3) 2208 256 load_balance+0xd9/0x662
I'm Cc'ing stable, although it's not urgent, as it only shows bogus
size for item #0 , the rest of the trace is legit. It should still be
corrected in previous stable releases.
Cc: stable@vger.kernel.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-03-15 00:36:07 -04:00
..
debug
module: add new state MODULE_STATE_UNFORMED.
2013-01-12 13:27:05 +10:30
events
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2013-02-19 17:49:41 -08:00
gcov
irq
Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2013-02-19 19:07:27 -08:00
power
Merge branch 'for-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
2012-12-12 08:18:24 -08:00
sched
Merge branch 'for-3.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
2013-02-19 22:01:33 -08:00
time
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2013-02-19 19:05:45 -08:00
trace
tracing: Fix stack tracer with fentry use
2013-03-15 00:36:07 -04:00
.gitignore
acct.c
cputime: Use accessors to read task cputime stats
2013-01-27 19:23:31 +01:00
async.c
Merge branch 'for-3.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
2013-02-19 22:01:33 -08:00
audit.c
kernel/audit.c: avoid negative sleep durations
2013-01-11 14:54:56 -08:00
audit.h
audit: optimize audit_compare_dname_path
2012-10-12 00:32:02 -04:00
audit_tree.c
audit: catch possible NULL audit buffers
2013-01-11 14:54:55 -08:00
audit_watch.c
audit: catch possible NULL audit buffers
2013-01-11 14:54:55 -08:00
auditfilter.c
audit: fix auditfilter.c kernel-doc warnings
2013-01-10 14:35:23 -08:00
auditsc.c
audit: catch possible NULL audit buffers
2013-01-11 14:54:55 -08:00
backtracetest.c
bounds.c
capability.c
cgroup.c
Merge branch 'akpm' (Andrew's patch-bomb)
2012-12-17 20:58:12 -08:00
cgroup_freezer.c
cgroup: rename ->create/post_create/pre_destroy/destroy() to ->css_alloc/online/offline/free()
2012-11-19 08:13:38 -08:00
compat.c
x32: fix sigtimedwait
2012-12-26 01:15:03 -05:00
configs.c
context_tracking.c
Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2013-02-19 18:19:48 -08:00
cpu.c
Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2013-02-19 19:04:55 -08:00
cpu_pm.c
cpuset.c
cpuset: use N_MEMORY instead N_HIGH_MEMORY
2012-12-12 17:38:32 -08:00
crash_dump.c
cred.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
2012-12-18 10:55:28 -08:00
delayacct.c
cputime: Use accessors to read task cputime stats
2013-01-27 19:23:31 +01:00
dma.c
elfcore.c
exec_domain.c
exit.c
cputime: Use accessors to read task cputime stats
2013-01-27 19:23:31 +01:00
extable.c
fork.c
This implements the cputime accounting on full dynticks CPUs.
2013-02-05 13:10:33 +01:00
freezer.c
freezer: change ptrace_stop/do_signal_stop to use freezable_schedule()
2012-10-26 14:27:49 -07:00
futex.c
sched/rt: Move rt specific bits into new header file
2013-02-07 20:51:08 +01:00
futex_compat.c
groups.c
hrtimer.c
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2013-02-19 19:05:45 -08:00
hung_task.c
irq_work.c
Merge branch 'nohz/printk-v8' into irq/core
2013-02-05 00:48:46 +01:00
itimer.c
jump_label.c
jump_label: Export jump_label_rate_limit()
2012-08-06 19:00:35 +03:00
kallsyms.c
kcmp.c
kcmp: include linux/ptrace.h
2012-12-20 17:40:19 -08:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks
locking: Adjust spin lock inlining Kconfig options
2012-09-13 17:56:13 +02:00
Kconfig.preempt
kexec.c
kdump: remove unneeded include
2012-10-06 03:05:19 +09:00
kfifo.c
kmod.c
Merge branch 'master' into for-3.9-async
2013-01-23 09:31:01 -08:00
kprobes.c
Merge branch 'for-3.9-cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
2013-02-19 21:58:52 -08:00
ksysfs.c
Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2012-12-11 18:10:49 -08:00
kthread.c
kthread: use N_MEMORY instead N_HIGH_MEMORY
2012-12-12 17:38:33 -08:00
latencytop.c
lglock.c
lockdep.c
lockdep: Check if nested lock is actually held
2012-09-13 17:00:44 +02:00
lockdep_internals.h
lockdep_proc.c
lockdep: Use KSYM_NAME_LEN'ed buffer for __get_key_name()
2012-10-24 12:39:09 +02:00
lockdep_states.h
Makefile
Nothing all that exciting; a new module-from-fd syscall for those who want
2012-12-19 07:55:08 -08:00
modsign_certificate.S
MODSIGN: Avoid using .incbin in C source
2012-12-14 13:06:44 +10:30
modsign_pubkey.c
keys: use keyring_alloc() to create module signing keyring
2012-12-20 17:40:21 -08:00
module-internal.h
MODSIGN: Move the magic string to the end of a module and eliminate the search
2012-10-19 17:30:40 -07:00
module.c
module: fix missing module_mutex unlock
2013-01-20 20:22:58 -08:00
module_signing.c
MODSIGN: Don't use enum-type bitfields in module signature info block
2012-12-05 11:27:24 +10:30
mutex-debug.c
mutex-debug.h
mutex.c
sched/rt: Move rt specific bits into new header file
2013-02-07 20:51:08 +01:00
mutex.h
notifier.c
nsproxy.c
userns: Implement unshare of the user namespace
2012-11-20 04:18:14 -08:00
padata.c
padata: use __this_cpu_read per-cpu helper
2012-12-06 17:16:23 +08:00
panic.c
panic: fix a possible deadlock in panic()
2012-07-30 17:25:13 -07:00
params.c
pid.c
kernel/pid.c: reenable interrupts when alloc_pid() fails because init has exited
2013-02-12 14:34:00 -08:00
pid_namespace.c
pidns: Stop pid allocation when init dies
2012-12-25 16:10:05 -08:00
posix-cpu-timers.c
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2013-02-19 19:05:45 -08:00
posix-timers.c
posix-timers: Fix clock_adjtime to always return timex data on success
2013-01-15 18:16:07 -08:00
printk.c
Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2013-02-19 17:47:58 -08:00
profile.c
profiling: Remove unused timer hook
2013-01-24 15:37:26 +01:00
ptrace.c
uprobes: Add exports for module use
2013-02-08 17:47:13 +01:00
range.c
rcu.h
rcu: Provide RCU CPU stall warnings for tiny RCU
2013-01-28 22:06:21 -08:00
rcupdate.c
Merge branches 'doctorture.2013.01.29a', 'fixes.2013.01.26a', 'tagcb.2013.01.24a' and 'tiny.2013.01.29b' into HEAD
2013-01-28 22:25:21 -08:00
rcutiny.c
Merge branches 'doctorture.2013.01.29a', 'fixes.2013.01.26a', 'tagcb.2013.01.24a' and 'tiny.2013.01.29b' into HEAD
2013-01-28 22:25:21 -08:00
rcutiny_plugin.h
rcu: Provide RCU CPU stall warnings for tiny RCU
2013-01-28 22:06:21 -08:00
rcutorture.c
rcu: Allow rcutorture to be built at low optimization levels
2013-02-04 12:18:20 -08:00
rcutree.c
Merge branches 'doctorture.2013.01.29a', 'fixes.2013.01.26a', 'tagcb.2013.01.24a' and 'tiny.2013.01.29b' into HEAD
2013-01-28 22:25:21 -08:00
rcutree.h
Merge branches 'doctorture.2013.01.29a', 'fixes.2013.01.26a', 'tagcb.2013.01.24a' and 'tiny.2013.01.29b' into HEAD
2013-01-28 22:25:21 -08:00
rcutree_plugin.h
rcu: Make rcu_nocb_poll an early_param instead of module_param
2013-01-08 14:12:19 -08:00
rcutree_trace.c
rcu: Separate accounting of callbacks from callback-free CPUs
2012-11-16 10:05:57 -08:00
relay.c
res_counter.c
res_counter: return amount of charges after res_counter_uncharge()
2012-12-18 15:02:12 -08:00
resource.c
kernel/resource.c: fix stack overflow in __reserve_region_with_split()
2012-10-06 03:05:31 +09:00
rtmutex-debug.c
sched/rt: Move rt specific bits into new header file
2013-02-07 20:51:08 +01:00
rtmutex-debug.h
rtmutex-tester.c
sched/rt: Move rt specific bits into new header file
2013-02-07 20:51:08 +01:00
rtmutex.c
sched/rt: Move rt specific bits into new header file
2013-02-07 20:51:08 +01:00
rtmutex.h
rtmutex_common.h
rwsem.c
lockdep, rwsem: provide down_write_nest_lock()
2013-01-11 14:54:55 -08:00
seccomp.c
seccomp: Make syscall skipping and nr changes more consistent
2012-10-02 21:14:29 +10:00
semaphore.c
signal.c
This implements the cputime accounting on full dynticks CPUs.
2013-02-05 13:10:33 +01:00
smp.c
smp: Fix SMP function call empty cpu mask race
2013-01-28 11:21:57 +01:00
smpboot.c
smpboot: Allow selfparking per cpu threads
2013-02-14 15:29:37 +01:00
smpboot.h
smpboot: Provide infrastructure for percpu hotplug threads
2012-08-13 17:01:07 +02:00
softirq.c
cputime: Safely read cputime of full dynticks CPUs
2013-01-27 20:35:47 +01:00
spinlock.c
srcu.c
srcu: use ACCESS_ONCE() to access sp->completed in srcu_read_lock()
2013-02-07 15:19:36 -08:00
stacktrace.c
stop_machine.c
stop_machine: Use smpboot threads
2013-02-14 15:29:38 +01:00
sys.c
cputime: Rename thread_group_times to thread_group_cputime_adjusted
2012-11-28 17:07:57 +01:00
sys_ni.c
module: add syscall to load module from fd
2012-12-14 13:05:22 +10:30
sysctl.c
sched/rt: Add a tuning knob to allow changing SCHED_RR timeslice
2013-02-07 20:51:07 +01:00
sysctl_binary.c
pidns: Use task_active_pid_ns where appropriate
2012-11-19 05:59:09 -08:00
task_work.c
task_work: task_work_add() should not succeed after exit_task_work()
2012-09-13 16:47:34 +02:00
taskstats.c
taskstats: cgroupstats_user_cmd() may leak on error
2012-10-06 03:05:31 +09:00
test_kprobes.c
time.c
time, Fix setting of hardware clock in NTP code
2013-02-08 15:07:05 -08:00
timeconst.pl
timeconst.pl: Eliminate Perl warning
2013-02-07 17:14:08 -08:00
timer.c
Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2013-02-19 18:19:48 -08:00
tracepoint.c
tsacct.c
cputime: Use accessors to read task cputime stats
2013-01-27 19:23:31 +01:00
uid16.c
up.c
user-return-notifier.c
user.c
proc: Usable inode numbers for the namespace file descriptors.
2012-11-20 04:19:49 -08:00
user_namespace.c
userns: Fix typo in description of the limitation of userns_install
2012-12-14 18:36:36 -08:00
utsname.c
userns: Require CAP_SYS_ADMIN for most uses of setns.
2012-12-14 16:12:03 -08:00
utsname_sysctl.c
wait.c
propagate name change to comments in kernel source
2012-12-06 10:39:54 +01:00
watchdog.c
sched/rt: Move rt specific bits into new header file
2013-02-07 20:51:08 +01:00
workqueue.c
workqueue: un-GPL function delayed_work_timer_fn()
2013-02-19 10:09:13 -08:00
workqueue_internal.h
workqueue: rename cpu_workqueue to pool_workqueue
2013-02-13 19:29:12 -08:00