linux/kernel
David P. Reed fa6a1a554b ntp: fix typo that makes sync_cmos_clock erratic
Fix a typo in ntp.c that has caused updating of the persistent (RTC)
clock when synced to NTP to behave erratically.

When debugging a freeze that arises on my AMD64 machines when I
run the ntpd service, I added a number of printk's to monitor the
sync_cmos_clock procedure.  I discovered that it was not syncing to
cmos RTC every 11 minutes as documented, but instead would keep trying
every second for hours at a time.  The reason turned out to be a typo
in sync_cmos_clock, where it attempts to ensure that
update_persistent_clock is called very close to 500 msec. after a 1
second boundary (required by the PC RTC's spec). That typo referred to
"xtime" in one spot, rather than "now", which is derived from "xtime"
but not equal to it.  This makes the test erratic, creating a
"coin-flip" that decides when update_persistent_clock is called - when
it is called, which is rarely, it may be at any time during the one
second period, rather than close to 500 msec, so the value written is
needlessly incorrect, too.

Signed-off-by: David P. Reed
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-11-17 16:27:01 +01:00
..
irq __do_IRQ does not check IRQ_DISABLED when IRQ_PER_CPU is set 2007-11-14 18:45:43 -08:00
power hibernate: fix lockdep report 2007-11-14 18:45:43 -08:00
time ntp: fix typo that makes sync_cmos_clock erratic 2007-11-17 16:27:01 +01:00
.gitignore gitignore: ignore more generated files 2006-01-03 11:35:26 +01:00
acct.c whitespace fixes: process accounting 2007-10-18 14:37:24 -07:00
audit_tree.c [PATCH] audit: watching subtrees 2007-10-21 02:37:45 -04:00
audit.c [PATCH] audit: watching subtrees 2007-10-21 02:37:45 -04:00
audit.h [PATCH] audit: watching subtrees 2007-10-21 02:37:45 -04:00
auditfilter.c [PATCH] audit: watching subtrees 2007-10-21 02:37:45 -04:00
auditsc.c auditsc: fix kernel-doc param warnings 2007-10-22 19:40:02 -07:00
capability.c Uninline find_pid etc set of functions 2007-10-19 11:53:41 -07:00
cgroup_debug.c Task Control Groups: simple task cgroup debug info subsystem 2007-10-19 11:53:36 -07:00
cgroup.c Improve cgroup printks 2007-11-14 18:45:37 -08:00
compat.c Merge ssh://master.kernel.org/pub/scm/linux/kernel/git/tglx/linux-2.6-hrt 2007-10-18 15:12:41 -07:00
configs.c use simple_read_from_buffer in kernel/ 2007-05-09 12:30:49 -07:00
cpu.c CPU HOTPLUG: avoid hotadd when proper possible_map isn't specified 2007-10-19 11:53:44 -07:00
cpuset.c hotplug cpu: migrate a task within its cpuset 2007-10-19 11:53:44 -07:00
delayacct.c Add scaled time to taskstats based process accounting 2007-10-18 14:37:28 -07:00
dma.c whitespace fixes: DMA channel allocator 2007-10-18 14:37:24 -07:00
exec_domain.c whitespace fixes: execution domains 2007-10-18 14:37:26 -07:00
exit.c wait_task_stopped: Check p->exit_state instead of TASK_TRACED 2007-11-15 08:36:27 -08:00
extable.c [PATCH] symbol_put_addr() locks kernel 2006-05-15 11:20:55 -07:00
fork.c sched: fix copy_namespace() <-> sched_fork() dependency in do_fork 2007-11-09 22:39:39 +01:00
futex_compat.c [FUTEX] Fix address computation in compat code. 2007-11-09 16:13:08 -08:00
futex.c kernel/futex.c: make 3 functions static 2007-11-05 21:53:46 +11:00
hrtimer.c Quieten hrtimer printk: "Switched to high resolution mode .." 2007-10-29 09:39:38 +01:00
itimer.c whitespace fixes: interval timers 2007-10-18 14:37:26 -07:00
kallsyms.c kallsyms: make KSYM_NAME_LEN include space for trailing '\0' 2007-07-17 10:23:03 -07:00
Kconfig.hz [PATCH] HZ: 300Hz support 2006-12-07 08:39:36 -08:00
Kconfig.instrumentation Linux Kernel Markers 2007-10-19 11:53:54 -07:00
Kconfig.preempt Move PREEMPT_NOTIFIERS into an always-included Kconfig 2007-10-17 08:42:55 -07:00
kexec.c Extended crashkernel command line 2007-10-19 11:53:49 -07:00
kfifo.c is_power_of_2: kernel/kfifo.c 2007-07-16 09:05:50 -07:00
kmod.c Restore call_usermodehelper_pipe() behaviour 2007-09-11 17:21:20 -07:00
kprobes.c kprobes: support kretprobe blacklist 2007-10-16 09:43:10 -07:00
ksysfs.c add-vmcore: cleanup the coding style according to Andrew's comments 2007-10-17 08:42:54 -07:00
kthread.c kthread: silence bogus section mismatch warning 2007-07-31 15:39:42 -07:00
latency.c [PATCH] severing module.h->sched.h 2006-12-04 02:00:22 -05:00
lockdep_internals.h [PATCH] lockdep: more chains 2006-12-07 08:39:43 -08:00
lockdep_proc.c lockdep: Avoid /proc/lockdep & lock_stat infinite output 2007-10-11 22:11:11 +02:00
lockdep.c lockdep: fix a typo in the __lock_acquire comment 2007-10-28 20:47:01 +01:00
Makefile revert "Task Control Groups: example CPU accounting subsystem" 2007-11-14 18:45:40 -08:00
marker.c Linux Kernel Markers: fix marker mutex not taken upon module load 2007-11-14 18:45:40 -08:00
module.c Linux Kernel Markers 2007-10-19 11:53:54 -07:00
mutex-debug.c [PATCH] remove many unneeded #includes of sched.h 2007-02-14 08:09:54 -08:00
mutex-debug.h [PATCH] lockdep: better lock debugging 2006-07-03 15:27:01 -07:00
mutex.c lockdep: fixup mutex annotations 2007-10-11 22:11:12 +02:00
mutex.h [PATCH] lockdep: prove mutex locking correctness 2006-07-03 15:27:04 -07:00
notifier.c Add kernel/notifier.c 2007-10-19 11:53:34 -07:00
ns_cgroup.c cgroups: implement namespace tracking subsystem 2007-10-19 11:53:37 -07:00
nsproxy.c pid namespaces: allow cloning of new namespace 2007-10-19 11:53:39 -07:00
panic.c trivial comment wording/typo fix regarding taint flags 2007-10-20 00:30:06 +02:00
params.c fix param_sysfs_builtin name length check 2007-11-14 18:45:42 -08:00
pid.c pidns: Place under CONFIG_EXPERIMENTAL 2007-11-14 18:45:43 -08:00
posix-cpu-timers.c Isolate some explicit usage of task->tgid 2007-10-19 11:53:40 -07:00
posix-timers.c Isolate some explicit usage of task->tgid 2007-10-19 11:53:40 -07:00
printk.c serial: turn serial console suspend a boot rather than compile time option 2007-10-18 14:37:19 -07:00
profile.c sched: document profile=sleep requiring CONFIG_SCHEDSTATS 2007-10-24 18:23:50 +02:00
ptrace.c Isolate some explicit usage of task->tgid 2007-10-19 11:53:40 -07:00
rcupdate.c Clean up duplicate includes in kernel/ 2007-10-17 08:42:48 -07:00
rcutorture.c Make rcutorture RNG use temporal entropy 2007-10-17 08:42:53 -07:00
relay.c whitespace fixes: relayfs 2007-10-18 14:37:24 -07:00
resource.c Add IORESOUCE_BUSY flag for System RAM 2007-11-14 18:45:39 -08:00
rtmutex_common.h FUTEX: Tidy up the code 2007-07-16 09:05:49 -07:00
rtmutex-debug.c Use helpers to obtain task pid in printks 2007-10-19 11:53:43 -07:00
rtmutex-debug.h [PATCH] lockdep: better lock debugging 2006-07-03 15:27:01 -07:00
rtmutex-tester.c Freezer: make kernel threads nonfreezable by default 2007-07-17 10:23:02 -07:00
rtmutex.c Use helpers to obtain task pid in printks 2007-10-19 11:53:43 -07:00
rtmutex.h [PATCH] lockdep: better lock debugging 2006-07-03 15:27:01 -07:00
rwsem.c lockstat: hook into spinlock_t, rwlock_t, rwsem and mutex 2007-07-19 10:04:49 -07:00
sched_debug.c sched: reintroduce the sched_min_granularity tunable 2007-11-09 22:39:37 +01:00
sched_fair.c sched: make sched_nr_latency static 2007-11-15 20:57:40 +01:00
sched_idletask.c sched: isolate SMP balancing code a bit more 2007-10-24 18:23:51 +02:00
sched_rt.c sched: isolate SMP balancing code a bit more 2007-10-24 18:23:51 +02:00
sched_stats.h sched: fix delay accounting regression 2007-11-09 22:39:37 +01:00
sched.c sched: reorder SCHED_FEAT_ bits 2007-11-15 20:57:40 +01:00
seccomp.c make seccomp zerocost in schedule 2007-07-16 09:05:50 -07:00
signal.c sigwait eats blocked default-ignore signals 2007-11-12 16:05:23 -08:00
softirq.c [KERNEL]: Unexport raise_softirq_irqoff 2007-10-10 16:49:18 -07:00
softlockup.c Use helpers to obtain task pid in printks 2007-10-19 11:53:43 -07:00
spinlock.c lockstat: hook into spinlock_t, rwlock_t, rwsem and mutex 2007-07-19 10:04:49 -07:00
srcu.c [PATCH] SRCU: report out-of-memory errors 2006-10-04 07:55:30 -07:00
stacktrace.c [PATCH] lockdep: stacktrace subsystem, core 2006-07-03 15:27:02 -07:00
stop_machine.c Fix stop_machine_run problem with naughty real time process 2007-07-16 09:05:41 -07:00
sys_ni.c [COMPAT]: Fix build on COMPAT platforms when CONFIG_NET is disabled. 2007-10-30 21:29:56 -07:00
sys.c x86: ignore the sys_getcpu() tcache parameter 2007-11-17 16:27:00 +01:00
sysctl_check.c [SYSCTL]: Fix warning for token-ring from sysctl checker 2007-11-13 21:15:24 -08:00
sysctl.c sysctl: check length at deprecated_sysctl_warning 2007-11-14 18:45:37 -08:00
taskstats.c kernel/taskstats.c: fix bogus nlmsg_free() 2007-11-14 18:45:44 -08:00
time.c whitespace fixes: time syscalls 2007-10-18 14:37:24 -07:00
timer.c sched: restore deterministic CPU accounting on powerpc 2007-11-09 22:39:38 +01:00
tsacct.c Add scaled time to taskstats based process accounting 2007-10-18 14:37:28 -07:00
uid16.c header cleaning: don't include smp_lock.h when not used 2007-05-08 11:15:07 -07:00
user_namespace.c Fix user namespace exiting OOPs 2007-09-19 11:24:18 -07:00
user.c sched: make cpu_shares_{show,store}() static 2007-10-24 18:23:50 +02:00
utsname_sysctl.c remove CONFIG_UTS_NS and CONFIG_IPC_NS 2007-07-16 09:05:47 -07:00
utsname.c Fix UTS corruption during clone(CLONE_NEWUTS) 2007-09-19 11:24:17 -07:00
wait.c Fix occurrences of "the the " 2007-05-09 08:57:56 +02:00
workqueue.c Use helpers to obtain task pid in printks 2007-10-19 11:53:43 -07:00