original_kernel/kernel
Arjan van de Ven 2c3b20e91f debug: add end-of-oops marker
Right now it's nearly impossible for parsers that collect kernel crashes
from logs or emails (such as www.kerneloops.org) to detect the
end-of-oops condition. In addition, it's not currently possible to
detect whether or not 2 oopses that look alike are actually the same
oops reported twice, or are truly two unique oopses.

This patch adds an end-of-oops marker, and makes the end marker include
a very simple 64-bit random ID to be able to detect duplicate reports.

Normally, this ID is calculated as a late_initcall() (in the hope that
at that time there is enough entropy to get a unique enough ID); however
for early oopses the oops_exit() function needs to generate the ID on
the fly.

We do this all at the _end_ of an oops printout, so this does not impact
our ability to get the most important portions of a crash out to the
console first.

[ Sidenote: the already existing oopses-since-bootup counter we print
  during crashes serves as the differentiator between multiple oopses
  that trigger during the same bootup. ]

Tested on 32-bit and 64-bit x86. Artificially injected very early
crashes as well, as expected they result in this constant ID after
multiple bootups:

  ---[ end trace ca143223eefdc828 ]---
  ---[ end trace ca143223eefdc828 ]---

because the random pools are still all zero. But it all still works
fine and causes no additional problems (which is the main goal of
instrumentation code).

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-12-20 15:01:17 +01:00
..
irq
power
time
.gitignore
Kconfig.hz
Kconfig.instrumentation
Kconfig.preempt
Makefile
acct.c
audit.c
audit.h
audit_tree.c
auditfilter.c
auditsc.c
capability.c
cgroup.c
cgroup_debug.c
compat.c
configs.c
cpu.c
cpuset.c
delayacct.c
dma.c
exec_domain.c
exit.c
extable.c
fork.c
futex.c
futex_compat.c
hrtimer.c
itimer.c
kallsyms.c
kexec.c
kfifo.c
kmod.c
kprobes.c
ksysfs.c
kthread.c
latency.c
lockdep.c
lockdep_internals.h
lockdep_proc.c
marker.c
module.c
mutex-debug.c
mutex-debug.h
mutex.c
mutex.h
notifier.c
ns_cgroup.c
nsproxy.c
panic.c
params.c
pid.c
posix-cpu-timers.c
posix-timers.c
printk.c
profile.c
ptrace.c
rcupdate.c
rcutorture.c
relay.c
resource.c
rtmutex-debug.c
rtmutex-debug.h
rtmutex-tester.c
rtmutex.c
rtmutex.h
rtmutex_common.h
rwsem.c
sched.c
sched_debug.c
sched_fair.c
sched_idletask.c
sched_rt.c
sched_stats.h
seccomp.c
signal.c
softirq.c
softlockup.c
spinlock.c
srcu.c
stacktrace.c
stop_machine.c
sys.c
sys_ni.c
sysctl.c
sysctl_check.c
taskstats.c
time.c
timer.c
tsacct.c
uid16.c
user.c
user_namespace.c
utsname.c
utsname_sysctl.c
wait.c
workqueue.c