This repository has been archived on 2026-03-14. You can view files and clone it, but cannot push or open issues or pull requests.

David Fries 6ffc787a44 system timer: fix crash in <100Hz system timer ...

The kernel has a divide by zero crash when trying to run the system timer
less than 100Hz.  The problem is x/(HZ/USER_HZ) and related.  Now
x*(USER_HZ/HZ) will be used if HZ<USER_HZ.

I'm running the Linux kernel under qemu and went to run a slower system
timer to take less CPU (and battery) on the host.  I found that the kernel
paniced under emulation because of a divide by zero in three places.  Here
is the patch.  The base git was updated today 01-05-2008.  I went for a
20Hz system time by adding config HZ_20 etc to kernel/Kconfig.hz.  With
this patch I verified the system timer by looking at /proc/interrupts.

[akpm@linux-foundation.org: partially clean up the macro maze]
Signed-off-by: David Fries <david@fries.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2008-02-06 10:41:10 -08:00

..

irq

genirq: stackdump after the "Trying to free already-free IRQ" message

2008-01-30 13:33:24 +01:00

power

kernel/power/disk.c: make code static

2008-02-05 09:44:22 -08:00

time

time: fix sysfs_show_{available,current}_clocksources() buffer overflow problem

2008-02-06 10:41:03 -08:00

.gitignore

…

acct.c

acct: real_parent ppid

2008-01-07 14:55:37 -08:00

audit_tree.c

[PATCH] audit: watching subtrees

2007-10-21 02:37:45 -04:00

audit.c

[AUDIT] ratelimit printk messages audit

2008-02-01 14:25:04 -05:00

audit.h

[PATCH] audit: watching subtrees

2007-10-21 02:37:45 -04:00

auditfilter.c

[AUDIT] make audit=0 really stop audit messages

2008-02-01 14:24:33 -05:00

auditsc.c

[AUDIT] create context if auditing was ever enabled

2008-02-01 14:24:45 -05:00

backtracetest.c

x86: add a simple backtrace test module

2008-01-30 13:33:08 +01:00

capability.c

Add 64-bit capability support to the kernel

2008-02-05 09:44:20 -08:00

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: replace per-subsystem mutexes with get_online_cpus()

2008-01-25 21:08:02 +01:00

cpuset.c

cpu-hotplug: replace lock_cpu_hotplug() with get_online_cpus()

2008-01-25 21:08:02 +01:00

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

do_wait: remove one "else if" branch

2008-02-06 10:41:04 -08:00

extable.c

module: Don't report discarded init pages as kernel text.

2008-01-29 17:13:18 +11:00

fork.c

idle_regs() must be __cpuinit

2008-02-06 10:41:08 -08:00

futex_compat.c

futex: Add bitset conditional wait/wakeup functionality

2008-02-01 17:45:14 +01:00

futex.c

futex: Add bitset conditional wait/wakeup functionality

2008-02-01 17:45:14 +01:00

hrtimer.c

timerfd: new timerfd API

2008-02-05 09:44:07 -08:00

itimer.c

whitespace fixes: interval timers

2007-10-18 14:37:26 -07:00

kallsyms.c

remove support for un-needed _extratext section

2008-02-06 10:41:01 -08:00

Kconfig.hz

sched: high-res preemption tick

2008-01-25 21:08:29 +01:00

Kconfig.preempt

sched: remove the !PREEMPT_BKL code

2008-01-25 21:08:33 +01:00

kexec.c

vmcoreinfo: add the array length of "free_list" for filtering free pages

2008-01-08 16:10:36 -08:00

kfifo.c

is_power_of_2: kernel/kfifo.c

2007-07-16 09:05:50 -07:00

kmod.c

Fix unbalanced helper_lock in kernel/kmod.c

2008-01-17 15:38:59 -08:00

kprobes.c

x86: kprobes: add kprobes smoke tests that run on boot

2008-01-30 13:32:53 +01:00

ksysfs.c

Kobject: convert remaining kobject_unregister() to kobject_put()

2008-01-24 20:40:40 -08:00

kthread.c

sched: fix, always create kernel threads with normal priority

2008-01-25 21:08:33 +01:00

latencytop.c

sched: latencytop support

2008-01-25 21:08:34 +01:00

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

softlockup: automatically detect hung TASK_UNINTERRUPTIBLE tasks

2008-01-25 21:08:02 +01:00

Makefile

latency.c: use QoS infrastructure

2008-02-05 09:44:22 -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

x86/non-x86: percpu, node ids, apic ids x86.git fixup

2008-01-30 13:33:32 +01:00

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

Add mutex_lock_killable

2007-12-06 17:37:59 -05:00

mutex.h

[PATCH] lockdep: prove mutex locking correctness

2006-07-03 15:27:04 -07:00

notifier.c

kernel/notifier.c should #include <linux/reboot.h>

2008-02-06 10:41:02 -08:00

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

debug: add the end-of-trace marker and the module list to

2008-01-30 13:32:50 +01:00

params.c

kernel/params.c: remove sparse-warning (different signedness)

2008-02-06 10:41:08 -08:00

pid.c

pidns: Place under CONFIG_EXPERIMENTAL

2007-11-14 18:45:43 -08:00

pm_qos_params.c

pm qos infrastructure and interface

2008-02-05 09:44:22 -08:00

posix-cpu-timers.c

sched: rt-watchdog: fix .rlim_max = RLIM_INFINITY

2008-01-25 21:08:32 +01:00

posix-timers.c

timerfd: new timerfd API

2008-02-05 09:44:07 -08:00

printk.c

printk.c: use unsigned ints instead of longs for logbuf index

2008-02-06 10:41:04 -08:00

profile.c

debug: clean up kernel/profile.c

2008-01-25 21:08:33 +01:00

ptrace.c

kernel/ptrace.c should #include <linux/syscalls.h>

2008-02-06 10:41:02 -08:00

rcuclassic.c

Preempt-RCU: implementation

2008-01-25 21:08:24 +01:00

rcupdate.c

Preempt-RCU: fix rcu_barrier for preemptive environment.

2008-01-25 21:08:24 +01:00

rcupreempt_trace.c

Preempt-RCU: implementation

2008-01-25 21:08:24 +01:00

rcupreempt.c

Preempt-RCU: CPU Hotplug handling

2008-01-25 21:08:25 +01:00

rcutorture.c

cpu-hotplug: replace lock_cpu_hotplug() with get_online_cpus()

2008-01-25 21:08:02 +01:00

relay.c

relay: nopage

2008-02-06 10:41:07 -08:00

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

Driver core: change sysdev classes to use dynamic kobject names

2008-01-24 20:40:40 -08:00

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

sched: mark rwsem functions as __sched for wchan/profiling

2007-12-18 15:21:13 +01:00

sched_debug.c

sched: keep total / count stats in addition to the max for

2008-01-25 21:08:35 +01:00

sched_fair.c

sched: let +nice tasks have smaller impact

2008-01-31 22:45:22 +01:00

sched_idletask.c

sched: high-res preemption tick

2008-01-25 21:08:29 +01:00

sched_rt.c

sched: fix goto retry in pick_next_task_rt()

2008-01-25 21:08:34 +01:00

sched_stats.h

sched: clean up kernel/sched_stat.h

2007-11-28 15:52:56 +01:00

sched.c

Merge branch 'task_killable' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc

2008-02-01 11:45:47 +11:00

seccomp.c

make seccomp zerocost in schedule

2007-07-16 09:05:50 -07:00

signal.c

Add arch_ptrace_stop

2008-02-06 10:41:07 -08:00

softirq.c

time: track accurate idle time with tick_sched.idle_sleeptime

2008-01-30 13:30:04 +01:00

softlockup.c

debug: softlockup looping fix

2008-02-02 14:27:45 +11:00

spinlock.c

spinlock: lockbreak cleanup

2008-01-30 13:31:20 +01:00

srcu.c

make srcu_readers_active() static

2008-02-06 10:41:02 -08:00

stacktrace.c

[PATCH] lockdep: stacktrace subsystem, core

2006-07-03 15:27:02 -07:00

stop_machine.c

stopmachine: semaphore to mutex

2008-02-06 10:41:08 -08:00

sys_ni.c

timerfd: new timerfd API

2008-02-05 09:44:07 -08:00

sys.c

kernel/sys.c: get rid of expensive divides in groups_sort()

2008-02-06 10:41:09 -08:00

sysctl_check.c

capabilities: introduce per-process capability bounding set

2008-02-05 09:44:20 -08:00

sysctl.c

get rid of NR_OPEN and introduce a sysctl_nr_open

2008-02-06 10:41:06 -08:00

taskstats.c

kernel/taskstats.c: fix bogus nlmsg_free()

2007-11-14 18:45:44 -08:00

test_kprobes.c

x86: kprobes: add kprobes smoke tests that run on boot

2008-01-30 13:32:53 +01:00

time.c

system timer: fix crash in <100Hz system timer

2008-02-06 10:41:10 -08:00

timer.c

taskstats scaled time cleanup

2008-02-06 10:41:00 -08:00

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

uids: merge multiple error paths in alloc_uid() into one

2008-01-25 21:08:26 +01:00

utsname_sysctl.c

Isolate the UTS namespace's domainname and hostname back

2007-11-29 09:24:53 -08:00

utsname.c

Fix UTS corruption during clone(CLONE_NEWUTS)

2007-09-19 11:24:17 -07:00

wait.c

wait: Use TASK_NORMAL

2007-12-06 17:34:36 -05:00

workqueue.c

cpu-hotplug: replace per-subsystem mutexes with get_online_cpus()

2008-01-25 21:08:02 +01:00