Steven Rostedt eb4a03780d function-graph: disable when both x86_32 and optimize for size are configured ... On x86_32, when optimize for size is set, gcc may align the frame pointer and make a copy of the the return address inside the stack frame. The return address that is located in the stack frame may not be the one used to return to the calling function. This will break the function graph tracer. The function graph tracer replaces the return address with a jump to a hook function that can trace the exit of the function. If it only replaces a copy, then the hook will not be called when the function returns. Worse yet, when the parent function returns, the function graph tracer will return back to the location of the child function which will easily crash the kernel with weird results. To see the problem, when i386 is compiled with -Os we get: c106be03: 57 push %edi c106be04: 8d 7c 24 08 lea 0x8(%esp),%edi c106be08: 83 e4 e0 and $0xffffffe0,%esp c106be0b: ff 77 fc pushl 0xfffffffc(%edi) c106be0e: 55 push %ebp c106be0f: 89 e5 mov %esp,%ebp c106be11: 57 push %edi c106be12: 56 push %esi c106be13: 53 push %ebx c106be14: 81 ec 8c 00 00 00 sub $0x8c,%esp c106be1a: e8 f5 57 fb ff call c1021614 <mcount> When it is compiled with -O2 instead we get: c10896f0: 55 push %ebp c10896f1: 89 e5 mov %esp,%ebp c10896f3: 83 ec 28 sub $0x28,%esp c10896f6: 89 5d f4 mov %ebx,0xfffffff4(%ebp) c10896f9: 89 75 f8 mov %esi,0xfffffff8(%ebp) c10896fc: 89 7d fc mov %edi,0xfffffffc(%ebp) c10896ff: e8 d0 08 fa ff call c1029fd4 <mcount> The compile with -Os will align the stack pointer then set up the frame pointer (%ebp), and it copies the return address back into the stack frame. The change to the return address in mcount is done to the copy and not the real place holder of the return address. Then compile with -O2 sets up the frame pointer first, this makes the change to the return address by mcount affect where the function will jump on exit. Reported-by: Jake Edge <jake@lwn.net> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>		2009-06-18 18:39:30 -04:00
..
irq	irq: slab alloc for default irq_affinity	2009-06-12 13:50:23 +03:00
power	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial	2009-06-14 13:46:25 -07:00
time	Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6	2009-06-11 09:01:14 +03:00
trace	function-graph: disable when both x86_32 and optimize for size are configured	2009-06-18 18:39:30 -04:00
.gitignore
acct.c	[CVE-2009-0029] System call wrappers part 04	2009-01-14 14:15:19 +01:00
async.c	async: Fix lack of boot-time console due to insufficient synchronization	2009-06-08 12:31:53 -07:00
audit_tree.c	Switch collect_mounts() to struct path	2009-06-11 21:36:01 -04:00
audit.c	Audit: remove spaces from audit_log_d_path	2009-04-05 13:49:04 -04:00
audit.h	fixing audit rule ordering mess, part 1	2009-01-04 15:14:41 -05:00
auditfilter.c	inotify: use GFP_NOFS in kernel_event() to work around a lockdep false-positive	2009-05-06 16:36:09 -07:00
auditsc.c	Audit: remove spaces from audit_log_d_path	2009-04-05 13:49:04 -04:00
backtracetest.c	backtrace: replace timer with tasklet + completions	2008-06-27 18:09:16 +02:00
bounds.c
capability.c	[CVE-2009-0029] System call wrappers part 04	2009-01-14 14:15:19 +01:00
cgroup_debug.c	debug cgroup: remove unneeded cgroup_lock	2009-04-02 19:04:54 -07:00
cgroup_freezer.c	freezer_cg: disable writing freezer.state of root cgroup	2008-11-12 17:17:16 -08:00
cgroup.c	Push BKL down into ->remount_fs()	2009-06-11 21:36:11 -04:00
compat.c	signals: implement sys_rt_tgsigqueueinfo	2009-04-30 19:24:24 +02:00
configs.c	kernel/configs.c: remove useless comments	2008-10-20 08:52:34 -07:00
cpu.c	cpumask: use set_cpu_active in init/main.c	2009-03-30 22:05:12 +10:30
cpuset.c	x86: remove some alloc_bootmem_cpumask_var calling	2009-06-11 19:27:07 +03:00
cred-internals.h	CRED: Inaugurate COW credentials	2008-11-14 10:39:23 +11:00
cred.c	CRED: Rename cred_exec_mutex to reflect that it's a guard against ptrace	2009-05-11 08:15:36 +10:00
delayacct.c	schedstat: consolidate per-task cpu runtime stats	2008-12-18 13:54:01 +01:00
dma-coherent.c	dma-coherent: Restore dma_alloc_from_coherent() large alloc fall back policy.	2009-01-21 18:51:53 +09:00
dma.c	kernel/dma.c: remove a CVS keyword	2008-10-16 11:21:30 -07:00
exec_domain.c	Get rid of indirect include of fs_struct.h	2009-03-31 23:00:27 -04:00
exit.c	Merge branch 'perfcounters-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2009-06-11 14:01:07 -07:00
extable.c	Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2009-04-05 11:04:19 -07:00
fork.c	Merge branch 'linus' into perfcounters/core	2009-06-11 17:55:42 +02:00
freezer.c	freezer_cg: use thaw_process() in unfreeze_cgroup()	2008-10-30 11:38:45 -07:00
futex_compat.c	CRED: Use RCU to access another task's creds and to release a task's own creds	2008-11-14 10:39:19 +11:00
futex.c	futex: fix restart in wait_requeue_pi	2009-05-20 10:34:32 +02:00
hrtimer.c	hrtimer: fix rq->lock inversion (again)	2009-03-31 14:52:52 +02:00
hung_task.c	softlockup: ensure the task has been switched out once	2009-02-11 11:04:16 +01:00
itimer.c	timers: split process wide cpu clocks/timers	2009-02-05 13:04:33 +01:00
kallsyms.c	kernel/kallsyms.c: replace deprecated __initcall with device_initcall and fix whitespace	2009-06-09 22:37:52 +02:00
Kconfig.freezer	container freezer: implement freezer cgroup subsystem	2008-10-20 08:52:34 -07:00
Kconfig.hz	sched: fix SCHED_HRTICK dependency	2008-07-28 14:37:38 +02:00
Kconfig.preempt	rcu: provide RCU options on non-preempt architectures too	2008-12-25 09:31:28 +01:00
kexec.c	PM core: rename suspend and resume functions	2009-06-12 21:32:31 +02:00
kfifo.c
kgdb.c	sysrq, intel_fb: fix sysrq g collision	2009-05-15 07:56:24 -05:00
kmod.c	kmod: Release sub_info on cred allocation failure.	2009-05-26 12:11:19 -07:00
kprobes.c	kprobes: fix to use text_mutex around arm/disarm kprobe	2009-05-08 16:23:48 -07:00
ksysfs.c	kernel/ksysfs.c:fix dependence on CONFIG_NET	2009-01-06 10:44:31 -08:00
kthread.c	tracing/events: move trace point headers into include/trace/events	2009-04-14 22:05:43 -04:00
latencytop.c	sched, latencytop: incorporate review feedback from Andrew Morton	2009-02-11 10:18:04 +01:00
lockdep_internals.h	lockdep: increase MAX_LOCKDEP_ENTRIES and MAX_LOCKDEP_CHAINS	2009-05-12 19:59:52 +02:00
lockdep_proc.c	lockstat: warn about disabled lock debugging	2009-02-14 23:28:28 +01:00
lockdep_states.h	lockdep: move state bit definitions around	2009-02-14 23:27:59 +01:00
lockdep.c	Merge branch 'linus' into tracing/core	2009-05-07 11:17:34 +02:00
Makefile	Merge branch 'linus' into perfcounters/core	2009-06-11 17:55:42 +02:00
marker.c	markers/tracpoints: fix non-modular build	2008-11-16 09:52:03 +01:00
module.c	module: trim exception table on init free.	2009-06-12 21:47:04 +09:30
mutex-debug.c	mutex: implement adaptive spinning	2009-01-14 18:09:02 +01:00
mutex-debug.h	mutex: implement adaptive spinning	2009-01-14 18:09:02 +01:00
mutex.c	Merge branch 'linus' into perfcounters/core	2009-06-11 17:55:42 +02:00
mutex.h	mutex: implement adaptive spinning	2009-01-14 18:09:02 +01:00
notifier.c	Merge commit 'v2.6.28-rc6' into core/debug	2008-11-26 08:22:50 +01:00
ns_cgroup.c	cgroups: relax ns_can_attach checks to allow attaching to grandchild cgroups	2009-04-02 19:04:53 -07:00
nsproxy.c	User namespaces: set of cleanups (v2)	2008-11-24 18:57:41 -05:00
panic.c	Fix caller information for warn_slowpath_null	2009-05-16 13:41:28 -07:00
params.c	module_param: allow 'bool' module_params to be bool, not just int.	2009-06-12 21:46:58 +09:30
perf_counter.c	perf_counter: Add forward/backward attribute ABI compatibility	2009-06-12 14:28:52 +02:00
pid_namespace.c	signals: zap_pid_ns_process() should use force_sig()	2009-04-02 19:04:58 -07:00
pid.c	pids: refactor vnr/nr_ns helpers to make them safe	2009-04-02 19:05:02 -07:00
pm_qos_params.c	pm_qos_requirement might sleep	2008-09-02 19:21:40 -07:00
posix-cpu-timers.c	kernel/posix-cpu-timers.c: fix sparse warning	2009-04-30 08:08:31 +02:00
posix-timers.c	[CVE-2009-0029] System call wrappers part 05	2009-01-14 14:15:20 +01:00
printk.c	Merge branch 'printk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2009-04-05 10:23:25 -07:00
profile.c	x86: remove some alloc_bootmem_cpumask_var calling	2009-06-11 19:27:07 +03:00
ptrace.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6	2009-06-11 10:01:41 -07:00
rcuclassic.c	kmemtrace, rcu: fix linux/rcutree.h and linux/rcuclassic.h dependencies	2009-04-03 12:23:02 +02:00
rcupdate.c	RCU: Don't try and predeclare inline funcs as it upsets some versions of gcc	2009-04-15 13:55:14 -07:00
rcupreempt_trace.c	"Tree RCU": scalable classic RCU implementation	2008-12-18 21:56:04 +01:00
rcupreempt.c	rcu: rcu_sched_grace_period(): kill the bogus flush_signals()	2009-05-05 20:28:05 +02:00
rcutorture.c	cpumask: convert rcutorture.c	2009-03-30 22:05:16 +10:30
rcutree_trace.c	rcu: Add __rcu_pending tracing to hierarchical RCU	2009-04-14 11:33:43 +02:00
rcutree.c	rcu: Add __rcu_pending tracing to hierarchical RCU	2009-04-14 11:33:43 +02:00
rcutree.h	kmemtrace, rcu: fix rcu_tree_trace.c data structure dependencies	2009-04-03 12:23:03 +02:00
relay.c	Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2009-04-05 11:04:19 -07:00
res_counter.c	memcg: memory cgroup resource counters for hierarchy	2009-01-08 08:31:05 -08:00
resource.c	Remove 'recurse into child resources' logic from 'reserve_region_with_split()'	2009-04-18 21:44:24 -07:00
rtmutex_common.h	rt_mutex: add proxy lock routines	2009-04-06 11:14:02 +02:00
rtmutex-debug.c
rtmutex-debug.h
rtmutex-tester.c	sysdev: Pass the attribute to the low level sysdev show/store function	2008-07-21 21:55:02 -07:00
rtmutex.c	trivial: fix ETIMEOUT -> ETIMEDOUT typos	2009-06-12 18:01:50 +02:00
rtmutex.h
rwsem.c
sched_clock.c	sched: Fix fallback sched_clock()'s offset when using jiffies	2009-05-09 10:08:19 +02:00
sched_cpupri.c	sched: use slab in cpupri_init()	2009-06-11 19:27:12 +03:00
sched_cpupri.h	cpumask: remove cpumask_t from core	2009-03-30 22:05:17 +10:30
sched_debug.c	sched: remove unused fields from struct rq	2009-03-24 23:16:51 +01:00
sched_fair.c	sched: remove redundant hierarchy walk in check_preempt_wakeup	2009-04-09 08:19:08 +02:00
sched_features.h	Merge branch 'locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2009-03-30 17:17:35 -07:00
sched_idletask.c	sched, timers: move calc_load() to scheduler	2009-05-15 15:32:45 +02:00
sched_rt.c	cpumask: alloc zeroed cpumask for static cpumask_var_ts	2009-06-09 22:30:27 +09:30
sched_stats.h	sched: remove unused fields from struct rq	2009-03-24 23:16:51 +01:00
sched.c	sched: export kick_process	2009-06-12 22:27:01 +09:30
seccomp.c	x86-64: seccomp: fix 32/64 syscall hole	2009-03-02 15:41:30 -08:00
semaphore.c	semaphore: __down_common: use signal_pending_state()	2008-08-05 14:33:47 -07:00
signal.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6	2009-06-11 10:01:41 -07:00
slow-work.c	slow_work_thread() should do the exclusive wait	2009-06-11 11:26:38 -07:00
smp.c	cpumask: alloc zeroed cpumask for static cpumask_var_ts	2009-06-09 22:30:27 +09:30
softirq.c	Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2009-06-10 19:53:40 -07:00
softlockup.c	softlockup: decouple hung tasks check from softlockup detection	2009-01-16 14:06:04 +01:00
spinlock.c	Allow rwlocks to re-enable interrupts	2009-04-02 19:05:11 -07:00
srcu.c
stacktrace.c	stacktrace: provide save_stack_trace_tsk() weak alias	2008-12-25 11:44:43 +01:00
stop_machine.c	cpumask: remove cpumask_t from core	2009-03-30 22:05:17 +10:30
sys_ni.c	Merge commit 'v2.6.29-rc2' into perfcounters/core	2009-01-21 16:37:27 +01:00
sys.c	Merge branch 'linus' into perfcounters/core	2009-04-29 14:47:05 +02:00
sysctl_check.c	net: add ARP notify option for devices	2009-02-01 01:04:33 -08:00
sysctl.c	Merge branch 'perfcounters-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2009-06-11 14:01:07 -07:00
taskstats.c	cpumask: convert rest of files in kernel/	2009-01-01 10:12:28 +10:30
test_kprobes.c	kprobes: add tests for register_kprobes	2009-01-06 15:59:20 -08:00
time.c	[CVE-2009-0029] System call wrappers part 01	2009-01-14 14:15:18 +01:00
timeconst.pl
timer.c	Merge branch 'linus' into x86/mce3	2009-06-11 23:31:52 +02:00
tracepoint.c	tracepoints: dont update zero-sized tracepoint sections	2009-03-18 19:55:00 +01:00
tsacct.c	Fix fixpoint divide exception in acct_update_integrals	2009-03-09 08:13:35 -07:00
uid16.c	[CVE-2009-0029] System call wrappers part 19	2009-01-14 14:15:26 +01:00
up.c	smp_call_function_single(): be slightly less stupid, fix #2	2009-01-12 16:04:37 +01:00
user_namespace.c	Fix recursive lock in free_uid()/free_user_ns()	2009-02-27 16:26:21 -08:00
user.c	Merge branch 'master' into next	2009-03-24 10:52:46 +11:00
utsname_sysctl.c	proc_sysctl: use CONFIG_PROC_SYSCTL around ipc and utsname proc_handlers	2009-04-02 19:05:01 -07:00
utsname.c	removed unused #include <linux/version.h>'s	2008-08-23 12:14:12 -07:00
wait.c	wait: don't use __wake_up_common()	2009-04-14 17:17:16 +02:00
workqueue.c	ftrace, workqueuetrace: make workqueue tracepoints use TRACE_EVENT macro	2009-06-02 01:10:40 +02:00