Linus Torvalds
039001972a
While testing some new changes for 3.18, I kept hitting a bug every so
...
often in the ring buffer. At first I thought it had to do with some
of the changes I was working on, but then testing something else I
realized that the bug was in 3.17 itself. I ran several bisects as the
bug was not very reproducible, and finally came up with the commit
that I could reproduce easily within a few minutes, and without the change
I could run the tests over an hour without issue. The change fit the
bug and I figured out a fix. That bad commit was:
Commit 651e22f270 "ring-buffer: Always reset iterator to reader page"
This commit fixed a bug, but in the process created another one. It used
the wrong value as the cached value that is used to see if things changed
while an iterator was in use. This made it look like a change always
happened, and could cause the iterator to go into an infinite loop.
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Merge tag 'trace-fixes-v3.17-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull trace ring buffer iterator fix from Steven Rostedt:
"While testing some new changes for 3.18, I kept hitting a bug every so
often in the ring buffer. At first I thought it had to do with some
of the changes I was working on, but then testing something else I
realized that the bug was in 3.17 itself. I ran several bisects as
the bug was not very reproducible, and finally came up with the commit
that I could reproduce easily within a few minutes, and without the
change I could run the tests over an hour without issue. The change
fit the bug and I figured out a fix. That bad commit was:
Commit 651e22f270 "ring-buffer: Always reset iterator to reader page"
This commit fixed a bug, but in the process created another one. It
used the wrong value as the cached value that is used to see if things
changed while an iterator was in use. This made it look like a change
always happened, and could cause the iterator to go into an infinite
loop"
* tag 'trace-fixes-v3.17-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ring-buffer: Fix infinite spin in reading buffer
2014-10-03 13:31:57 -07:00
..
bpf
net: filter: split 'struct sk_filter' into socket and bpf parts
2014-08-02 15:03:58 -07:00
debug
kdb: Use ktime_get_ts()
2014-06-12 16:18:45 +02:00
events
perf: fix perf bug in fork()
2014-10-02 16:28:44 -07:00
gcov
kernel/gcov/fs.c: remove unnecessary null test before debugfs_remove
2014-08-08 15:57:24 -07:00
irq
irq: Export handle_fasteoi_irq
2014-08-25 21:13:30 +02:00
locking
arch, locking: Ciao arch_mutex_cpu_relax()
2014-07-17 12:32:47 +02:00
power
Revert "PM / Hibernate: Iterate over set bits instead of PFNs in swsusp_free()"
2014-09-25 00:59:54 +02:00
printk
kernel/printk/printk.c: fix faulty logic in the case of recursive printk
2014-09-10 15:42:12 -07:00
rcu
rcu: Make nocb leader kthreads process pending callbacks after spawning
2014-08-28 05:59:59 -07:00
sched
Merge branches 'pm-sleep', 'pm-cpufreq' and 'pm-cpuidle'
2014-08-11 23:19:48 +02:00
time
alarmtimer: Lock k_itimer during timer callback
2014-09-12 13:59:12 -07:00
trace
ring-buffer: Fix infinite spin in reading buffer
2014-10-02 16:51:18 -04:00
.gitignore
Ignore generated file kernel/x509_certificate_list
2013-12-10 18:21:34 +00:00
acct.c
kernel/acct.c: fix coding style warnings and errors
2014-08-08 15:57:27 -07:00
async.c
audit.c
CAPABILITIES: remove undefined caps from all processes
2014-07-24 21:53:47 +10:00
audit.h
audit: Use struct net not pid_t to remember the network namespce to reply in
2014-03-20 10:10:53 -04:00
audit_tree.c
inotify: Fix reporting of cookies for inotify events
2014-02-18 11:17:17 +01:00
audit_watch.c
inotify: Fix reporting of cookies for inotify events
2014-02-18 11:17:17 +01:00
auditfilter.c
kernel/auditfilter.c: replace count*size kmalloc by kcalloc
2014-08-06 18:01:12 -07:00
auditsc.c
auditsc: audit_krule mask accesses need bounds checking
2014-06-10 08:44:40 -07:00
backtracetest.c
kernel/backtracetest.c: replace no level printk by pr_info()
2014-06-04 16:54:14 -07:00
bounds.c
page-cgroup: get rid of NR_PCG_FLAGS
2014-08-08 15:57:18 -07:00
capability.c
CAPABILITIES: remove undefined caps from all processes
2014-07-24 21:53:47 +10:00
cgroup.c
cgroup: fix unbalanced locking
2014-09-18 12:32:52 -04:00
cgroup_freezer.c
cgroup: rename cgroup_subsys->base_cftypes to ->legacy_cftypes
2014-07-15 11:05:09 -04:00
compat.c
compat: nanosleep: Clarify error handling
2014-09-06 12:58:18 +02:00
configs.c
context_tracking.c
x86/kprobes: Fix build errors and blacklist context_track_user
2014-06-14 09:07:44 +02:00
cpu.c
sched: Rework check_for_tasks()
2014-07-05 11:17:45 +02:00
cpu_pm.c
cpuset.c
cpuset: PF_SPREAD_PAGE and PF_SPREAD_SLAB should be atomic flags
2014-09-24 22:16:06 -04:00
crash_dump.c
cred.c
delayacct.c
delayacct: Remove braindamaged type conversions
2014-07-23 10:18:06 -07:00
dma.c
elfcore.c
exec_domain.c
kernel/exec_domain.c: code clean-up
2014-06-04 16:54:15 -07:00
exit.c
kernel/exit.c: fix coding style warnings and errors
2014-08-08 15:57:22 -07:00
extable.c
asmlinkage: Make main_extable_sort_needed visible
2014-02-13 18:13:22 -08:00
fork.c
perf: fix perf bug in fork()
2014-10-02 16:28:44 -07:00
freezer.c
libata, freezer: avoid block device removal while system is frozen
2013-12-19 13:50:32 -05:00
futex.c
futex: Unlock hb->lock in futex_wait_requeue_pi() error path
2014-09-12 22:04:36 +02:00
futex_compat.c
compat: Get rid of (get|put)_compat_time(val|spec)
2014-02-02 14:09:12 -08:00
groups.c
kernel/groups.c: remove return value of set_groups
2014-04-03 16:21:05 -07:00
hung_task.c
kernel/hung_task.c: convert simple_strtoul to kstrtouint
2014-06-04 16:54:15 -07:00
irq_work.c
irq_work: Remove BUG_ON in irq_work_run()
2014-07-05 11:17:26 +02:00
jump_label.c
kallsyms.c
kernel/kallsyms.c: fix %pB when there's no symbol at the address
2014-08-08 15:57:18 -07:00
kcmp.c
kcmp: fix standard comparison bug
2014-09-10 15:42:12 -07:00
Kconfig.freezer
Kconfig.hz
kernel: remove CONFIG_USE_GENERIC_SMP_HELPERS
2013-11-15 09:32:22 +09:00
Kconfig.locks
locking/rwsem: Add CONFIG_RWSEM_SPIN_ON_OWNER
2014-07-16 14:57:13 +02:00
Kconfig.preempt
kexec.c
kexec: create a new config option CONFIG_KEXEC_FILE for new syscall
2014-08-29 16:28:16 -07:00
kmod.c
signals: change wait_for_helper() to use kernel_sigaction()
2014-06-06 16:08:12 -07:00
kprobes.c
kprobes: Skip kretprobe hit in NMI context to avoid deadlock
2014-08-08 10:38:04 +02:00
ksysfs.c
kobject: Make support for uevent_helper optional.
2014-04-25 12:00:49 -07:00
kthread.c
kthread_work: wake up worker only when the worker is idle
2014-07-28 14:07:52 -04:00
latencytop.c
kernel/latencytop.c: convert seq_printf to seq_puts
2014-06-04 16:54:15 -07:00
Makefile
bin2c: move bin2c in scripts/basic
2014-08-08 15:57:32 -07:00
module-internal.h
module.c
module: Clean up ro/nx after early module load failures
2014-08-16 04:47:00 +09:30
module_signing.c
notifier.c
kprobes, notifier: Use NOKPROBE_SYMBOL macro in notifier
2014-04-24 10:26:39 +02:00
nsproxy.c
namespaces: Use task_lock and not rcu to protect nsproxy
2014-07-29 18:08:50 -07:00
padata.c
padata: Fix wrong usage of rcu_dereference()
2013-12-05 21:28:42 +08:00
panic.c
panic: add TAINT_SOFTLOCKUP
2014-08-08 15:57:24 -07:00
params.c
Add module param type 'ullong'
2014-07-17 22:07:37 +02:00
pid.c
pid_namespace.c
pid_namespace: pidns_get() should check task_active_pid_ns() != NULL
2014-04-02 16:20:21 -07:00
profile.c
kernel/profile.c: use static const char instead of static char
2014-06-06 16:08:13 -07:00
ptrace.c
sched: Remove proliferation of wait_on_bit() action functions
2014-07-16 15:10:39 +02:00
range.c
reboot.c
kernel/reboot.c: convert simple_strtoul to kstrtoint
2014-06-04 16:54:15 -07:00
relay.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
2014-04-12 14:49:50 -07:00
res_counter.c
kernel/res_counter.c: replace simple_strtoull by kstrtoull
2014-06-04 16:54:15 -07:00
resource.c
resource: fix the case of null pointer access
2014-08-29 16:28:15 -07:00
seccomp.c
seccomp: Replace BUG(!spin_is_locked()) with assert_spin_lock
2014-08-11 13:29:12 -07:00
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
kernel/smp.c:on_each_cpu_cond(): fix warning in fallback path
2014-08-06 18:01:22 -07:00
smpboot.c
smpboot.h
softirq.c
Merge branch 'rcu/next' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
2014-05-22 11:36:10 +02:00
stacktrace.c
stop_machine.c
kernel/stop_machine.c: kernel-doc warning fix
2014-06-04 16:54:15 -07:00
sys.c
sched: move no_new_privs into new atomic flags
2014-07-18 12:13:38 -07:00
sys_ni.c
kexec: new syscall kexec_file_load() declaration
2014-08-08 15:57:32 -07:00
sysctl.c
mm, hugetlb: remove hugetlb_zero and hugetlb_infinity
2014-08-06 18:01:19 -07:00
sysctl_binary.c
ipv6: Allow accepting RA from local IP addresses.
2014-07-01 12:16:24 -07:00
system_certificates.S
KEYS: correct alignment of system_certificate_list content in assembly file
2013-12-10 18:25:28 +00:00
system_keyring.c
KEYS: validate certificate trust only with builtin keys
2014-07-17 09:35:17 -04:00
task_work.c
taskstats.c
genetlink: only pass array to genl_register_family_with_ops()
2013-11-19 16:39:05 -05:00
test_kprobes.c
kernel/test_kprobes.c: use current logging functions
2014-08-08 15:57:18 -07:00
torture.c
torture: Avoid format string leak to thead name
2014-07-07 10:12:56 -07:00
tracepoint.c
tracing: syscall_regfunc() should not skip kernel threads
2014-06-21 00:15:26 -04:00
tsacct.c
sched: Make task->start_time nanoseconds based
2014-07-23 10:18:05 -07:00
uid16.c
up.c
smp: Rename __smp_call_function_single() to smp_call_function_single_async()
2014-02-24 14:47:15 -08:00
user-return-notifier.c
user.c
kernel/user.c: drop unused field 'files' from user_struct
2014-06-04 16:54:16 -07:00
user_namespace.c
proc: constify seq_operations
2014-08-08 15:57:22 -07:00
utsname.c
namespaces: Use task_lock and not rcu to protect nsproxy
2014-07-29 18:08:50 -07:00
utsname_sysctl.c
sysctl: convert use of typedef ctl_table to struct ctl_table
2014-06-06 16:08:16 -07:00
watchdog.c
panic: add TAINT_SOFTLOCKUP
2014-08-08 15:57:24 -07:00
workqueue.c
Merge branch 'for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
2014-08-04 10:09:27 -07:00
workqueue_internal.h
workqueue: rename manager_mutex to attach_mutex
2014-05-20 10:59:32 -04:00