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* [PATCH] fix jiffies clocksource inittimejohn stultz2007-04-05
| | | | | | | | | | | | | | | | | | | | | | | In debugging a problem w/ the -rt tree, I noticed that on systems that mark the tsc as unstable before it is registered, the TSC would still be selected and used for a short period of time. Digging in it looks to be a result of the mix of the clocksource list changes and my clocksource initialization changes. With the -rt tree, using a bad TSC, even for a short period of time can results in a hang at boot. I was not able to reproduce this hang w/ mainline, but I'm not completely certain that someone won't trip on it. This patch resolves the issue by initializing the jiffies clocksource earlier so a bad TSC won't get selected just because nothing else is yet registered. Signed-off-by: John Stultz <johnstul@us.ibm.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] swsusp: fix memory shrinkerRafael J. Wysocki2007-04-05
| | | | | | | | | | | | | | | Fix a bug in the swsusp's memory shrinker that causes some systems using highmem to refuse to suspend to disk if image_size is set above 1/2 of available RAM. Special thanks to Jiri Slaby for reporting the problem and assistance in debugging it. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: Jiri Slaby <jirislaby@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] kernel/time.c: add missing symbol exportsThomas Bittermann2007-04-04
| | | | | | | | | | | | | | | | | | This patch adds 2 missing symbol exports: jiffies_to_timeval() and timeval_to_jiffies(). The (not yet merged) dm-raid4-5 module will need them, and they used to be indirectly exported by virtue of being inline functions. Commit 8b9365d753d9870bb6451504c13570b81923228f ("[PATCH] Uninline jiffies.h functions") uninlined them, and thus modules now need them explicitly exported to use them. Signed-off-by: Thomas Bittermann <t.bittermann@online.de> Acked-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: john stultz <johnstul@us.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] Fix microcode-related suspend problemRafael J. Wysocki2007-04-02
| | | | | | | | | | | | | | | | | | | | Fix the regression resulting from the recent change of suspend code ordering that causes systems based on Intel x86 CPUs using the microcode driver to hang during the resume. The problem occurs since the microcode driver uses request_firmware() in its CPU hotplug notifier, which is called after tasks has been frozen and hangs. It can be fixed by telling the microcode driver to use the microcode stored in memory during the resume instead of trying to load it from disk. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Adrian Bunk <bunk@stusta.de> Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk> Cc: Pavel Machek <pavel@ucw.cz> Cc: Maxim <maximlevitsky@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] driver core: fix built-in drivers sysfs linksKay Sievers2007-04-02
| | | | | | | | | | | built-in drivers had broken sysfs links that caused bootup hangs for certain driver unregistry sequences. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] pid: Properly detect orphaned process groups in exit_notifyEric W. Biederman2007-03-29
| | | | | | | | | | | | | | | | | | | | | | In commit 0475ac0845f9295bc5f69af45f58dff2c104c8d1 when converting the orphaned process group handling to use struct pid I made a small mistake. I accidentally replaced an == with a !=. Besides just being a dumb thing to do apparently this has a bad side effect. The improper orphaned process group detection causes kwin to die after a suspend/resume cycle. I'm amazed this patch has been around as long as it has without anyone else noticing something funny going on. And the following people deserve credit for spotting and helping to reproduce this. Thanks to: Sid Boyce <g3vbv@blueyonder.co.uk> Thanks to: "Michael Wu" Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] hrtimers: fix reprogramming SMP raceIngo Molnar2007-03-28
| | | | | | | | | | | | | | | hrtimer_start() incorrectly set the 'reprogram' flag to enqueue_hrtimer(), which should only be 1 if the hrtimer is queued to the current CPU. Doing otherwise could result in a reprogramming of the current CPU's clockevents device, with a timer that is not queued to it - resulting in a bogus next expiry value. Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Michal Piotrowski <michal.k.k.piotrowski@gmail.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] Revert "swsusp: disable nonboot CPUs before entering platform suspend"Rafael J. Wysocki2007-03-27
| | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit 94985134b7b46848267ed6b734320db01c974e72 and insteads removes the WARN_ON() that caused that commit in the first place. The problem is that we call disable_nonboot_cpus() in swsusp before powering down the system in order to avoid triggering the WARN_ON() in arch/x86_64/kernel/acpi/sleep.c:init_low_mapping() and this doesn't work well on Thomas' system. So instead, remove the WARN_ON() in arch/x86_64/kernel/acpi/sleep.c: init_low_mapping(), which triggers every time during the suspend to disk in the platform mode, as the potential problem it is related to doesn't seem to occur in practice. [ I think we might want to disallow the case of multiple users of that mm, or something. Normally, playing with the current process page tables on the current CPU should be fine as long as we don't have other threads using those tables at the same time.. Anyway, not pretty, but better than the warning or the lockup - Linus ] Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] ntp: avoid time_offset overflowsjohn stultz2007-03-27
| | | | | | | | | | | | | | | | | | I've been seeing some odd NTP behavior recently on a few boxes and finally narrowed it down to time_offset overflowing when converted to SHIFT_UPDATE units (which was a side effect from my HZfreeNTP patch). This patch converts time_offset from a long to a s64 which resolves the issue. [tglx@linutronix.de: signedness fixes] Signed-off-by: John Stultz <johnstul@us.ibm.com> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: john stultz <johnstul@us.ibm.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>
* [PATCH] clockevents: remove bad designed sysfs support for nowThomas Gleixner2007-03-26
| | | | | | | | | | | | | The current sysfs support of clockevents does not obey the "only one value per file" rule. The real fix is not 2.6.21 material. Therefor remove the sysfs support for now. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] clocksource: Fix thinko in watchdog selectionThomas Gleixner2007-03-25
| | | | | | | | | | | | | | | | | The watchdog implementation excludes low res / non continuous clocksources from being selected as a watchdog reference unintentionally. Allow using jiffies/PIT as a watchdog reference as long as no better clocksource is available. This is necessary to detect TSC breakage on systems, which have no pmtimer/hpet. The main goal of the initial patch (preventing to switch to highres/nohz when no reliable fallback clocksource is available) is still guaranteed by the checks in clocksource_watchdog(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] dynticks: fix hrtimer rounding error in next_timer_interruptThomas Gleixner2007-03-25
| | | | | | | | | | | | | | | | | | | | | | | | The rework of next_timer_interrupt() fixed the timer wheel bugs, but invented a rounding error versus the next hrtimer event. This is caused by the conversion of the hrtimer internal representation to relative jiffies. This causes bug #8100: http://bugzilla.kernel.org/show_bug.cgi?id=8100 next_timer_interrupt() returns "now" in such a case and causes the code in tick_nohz_stop_sched_tick() to trigger the timer softirq, which is bogus as no timer is due for expiry. This results in an endless context switching between idle and ksoftirqd until a timer is due for expiry. Modify the hrtimer evaluation so that, it returns now + 1, when the conversion results in a delta < 1 jiffie. It's confirmed to resolve bug #8100 Reported-by: Emil Karlson <jkarlson@cc.hut.fi> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] time: fix formatting in /proc/timer_listJames Morris2007-03-23
| | | | | | | | | | | Fix the print formatting of three unsigned long fields in /proc/timer_list, which are currently being formatted as signed long. Signed-off-by: James Morris <jmorris@namei.org> Acked-by: 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>
* [PATCH] lockdep: debug_show_all_locks & debug_show_held_locks vs. debug_locksJarek Poplawski2007-03-22
| | | | | | | | | | | | | | | | | | | lockdep's data shouldn't be used when debug_locks == 0 because it's not updated after this, so it's more misleading than helpful. PS: probably lockdep's current-> fields should be reset after it turns debug_locks off: so, after printing a bug report, but before return from exported functions, but there are really a lot of these possibilities (e.g. after DEBUG_LOCKS_WARN_ON), so, something could be missed. (Of course direct use of this fields isn't recommended either.) Reported-by: Folkert van Heusden <folkert@vanheusden.com> Inspired-by: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Jarek Poplawski <jarkao2@o2.pl> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] fix extra BIOS invocation during resumePavel Machek2007-03-22
| | | | | | | | | | | | | | | | It causes extra moon icons blinking on x60, and breaks at least two other systems. During resume, we do not know that "reboot"/"shutdown" method was used, so we assume "plaform" and call BIOS, anyway... This is 2.6.21 material, and should fix 2 or 3 regressions from 2.6.20. Signed-off-by: Pavel Machek <pavel@suse.cz> Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] swsusp: Fix SNAPSHOT_S2RAM ioctlRafael J. Wysocki2007-03-22
| | | | | | | | | | The SNAPSHOT_S2RAM ioctl does not disable the nonboot CPUs before entering the suspend, although it should do this. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] clockevents: Fix suspend/resume to disk hangsThomas Gleixner2007-03-16
| | | | | | | | | | | | | | | | | | | | | | I finally found a dual core box, which survives suspend/resume without crashing in the middle of nowhere. Sigh, I never figured out from the code and the bug reports what's going on. The observed hangs are caused by a stale state transition of the clock event devices, which keeps the RCU synchronization away from completion, when the non boot CPU is brought back up. The suspend/resume in oneshot mode needs the similar care as the periodic mode during suspend to RAM. My assumption that the state transitions during the different shutdown/bringups of s2disk would go through the periodic boot phase and then switch over to highres resp. nohz mode were simply wrong. Add the appropriate suspend / resume handling for the non periodic modes. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] initialise pi_lock if CONFIG_RT_MUTEXES=NZilvinas Valinskas2007-03-16
| | | | | | | | | Fixes a bogus lockdep warning which causes lockdep to disable itself. Acked-by: Ingo Molnar <mingo@elte.hu> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] futex: PI state locking fixIngo Molnar2007-03-16
| | | | | | | | | | | | Testing of -rt by IBM uncovered a locking bug in wake_futex_pi(): the PI state needs to be locked before we access it. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Chuck Ebbert <cebbert@redhat.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] swsusp: fix suspend when console is in VT_AUTO+KD_GRAPHICS modeAndrew Johnson2007-03-16
| | | | | | | | | | | | | | | | When the console is in VT_AUTO+KD_GRAPHICS mode, switching to the SUSPEND_CONSOLE fails, resulting in vt_waitactive() waiting indefinitely or until the task is interrupted. This patch tests if a console switch can occur in set_console() and returns early if a console switch is not possible. [akpm@linux-foundation.org: cleanup] Signed-off-by: Andrew Johnson <ajohnson@intrinsyc.com> Acked-by: Pavel Machek <pavel@ucw.cz> Cc: "Antonino A. Daplas" <adaplas@pol.net> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] hrtimer: fix up unlocked access to wall_to_monotonicThomas Gleixner2007-03-16
| | | | | | | | | | | | | | commit f4304ab21513b834c8fe3403927c60c2b81a72d7 (HZ free NTP) moved the access to wall_to_monotonic in hrtimer_get_softirq_time() out of the xtime_lock protection. Move it back into the seq_lock section. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <johnstul@us.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] hrtimer: prevent overrun DoS in hrtimer_forward()Thomas Gleixner2007-03-16
| | | | | | | | | | | | | | | | | hrtimer_forward() does not check for the possible overflow of timer->expires. This can happen on 64 bit machines with large interval values and results currently in an endless loop in the softirq because the expiry value becomes negative and therefor the timer is expired all the time. Check for this condition and set the expiry value to the max. expiry time in the future. The fix should be applied to stable kernel series as well. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] swsusp: disable nonboot CPUs before entering platform suspendRafael J. Wysocki2007-03-16
| | | | | | | | | | | Prevent the WARN_ON() in arch/x86_64/kernel/acpi/sleep.c:init_low_mapping() from triggering by disabling nonboot CPUs before we finally enter the platform suspend. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] swsusp: Fix resume error path in platform modeRafael J. Wysocki2007-03-16
| | | | | | | | | | | If swsusp is using the platform mode during the resume and the image cannot be read, the platform mode should be switched off before software_resume() returns. Make it happen. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] fix deadlock in audit_log_task_context()Al Viro2007-03-14
| | | | | | | | | | GFP_KERNEL allocations in non-blocking context; fixed by killing an idiotic use of security_getprocattr(). Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Revert "driver core: refcounting fix"Greg Kroah-Hartman2007-03-09
| | | | | | | | | | This reverts commit 63ce18cfe685115ff8d341bae4c9204a79043cf0. It was the incorrect fix and causes a reference counting bug whenever any driver module is removed from the system. Mike Galbraith <efault@gmx.de> is looking for the real fix for his problem. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Merge master.kernel.org:/pub/scm/linux/kernel/git/lethal/sh-2.6Linus Torvalds2007-03-07
|\ | | | | | | | | | | | | | | | | | | | | | | | | * master.kernel.org:/pub/scm/linux/kernel/git/lethal/sh-2.6: sh: Kill off I/O cruft for R7780RP. sh: Revert lazy dcache writeback changes. sh: Enable SM501 support for RTS7751R2D. sh: Use L1_CACHE_BYTES for .data.cacheline_aligned. sysctl: Support vdso_enabled sysctl on SH. sh: Fix kernel thread stack corruption with preempt. doc: Add SH to vdso and earlyprintk in kernel-parameters.txt sh: Fix sigmask trampling in signal delivery. sh: Clear UBC when not in use.
| * sysctl: Support vdso_enabled sysctl on SH.Paul Mundt2007-03-05
| | | | | | | | | | | | | | All of the logic for this was already in place, we just hadn't wired it up in the sysctl table. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* | [PATCH] kconfig: Update swsusp descriptionRafael J. Wysocki2007-03-06
| | | | | | | | | | | | | | | | | | Update the outdated and inaccurate description of the software suspend in Kconfig. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | [PATCH] Publish rcutorture module parameters via sysfs, read-onlyJosh Triplett2007-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | rcutorture's module parameters currently use permissions of 0, so they don't show up in /sys/module/rcutorture/parameters. Change the permissions on all module parameters to world-readable (0444). rcutorture does all of its initialization and thread startup when loaded and relies on the parameters not changing during execution, so they should not permit writing. However, reading seems fine. Signed-off-by: Josh Triplett <josh@freedesktop.org> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | [PATCH] fix vsyscall settimeofdayDaniel Walker2007-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I've only seen this on x86_64. The vsyscall state only gets updated when a timer interrupts comes in. So if the time is set long before the next timer, there will be a period when a gettimeofday() won't reflect the correct time. I added an explicit update_vsyscall() during the settimeofday(), that way the vsyscall state doesn't get stale. Signed-off-by: Daniel Walker <dwalker@mvista.com> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | [PATCH] highres: do not run the TIMER_SOFTIRQ after switching to highres modeThomas Gleixner2007-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The TIMER_SOFTIRQ runs the hrtimers during bootup until a usable clocksource and clock event sources are registered. The switch to high resolution mode happens inside of the TIMER_SOFTIRQ, but runs the softirq afterwards. That way the tick emulation timer, which was set up in the switch to highres might be executed in the softirq context, which is a BUG. The rbtree has not to be touched by the softirq after the highres switch. This BUG was observed by Andres Salomon, who provided the information to debug it. Return early from the softirq, when the switch was sucessful. [dilinger@debian.org: add debug warning] [akpm@linux-foundation.org: make debug warning compile] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andres Salomon <dilinger@debian.org> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andres Salomon <dilinger@debian.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | [PATCH] Save/restore periodic tick information over suspend/resumeThomas Gleixner2007-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The programming of periodic tick devices needs to be saved/restored across suspend/resume - otherwise we might end up with a system coming up that relies on getting a PIT (or HPET) interrupt, while those devices default to 'no interrupts' after powerup. (To confuse things it worked to a certain degree on some systems because the lapic gets initialized as a side-effect of SMP bootup.) This suspend / resume thing was dropped unintentionally during the last-minute -mm code reshuffling. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | [PATCH] timer/hrtimer: take per cpu locks in sane orderHeiko Carstens2007-03-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Doing something like this on a two cpu system # echo 0 > /sys/devices/system/cpu/cpu0/online # echo 1 > /sys/devices/system/cpu/cpu0/online # echo 0 > /sys/devices/system/cpu/cpu1/online will give me this: ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.21-rc2-g562aa1d4-dirty #7 ------------------------------------------------------- bash/1282 is trying to acquire lock: (&cpu_base->lock_key){.+..}, at: [<000000000005f17e>] hrtimer_cpu_notify+0xc6/0x240 but task is already holding lock: (&cpu_base->lock_key#2){.+..}, at: [<000000000005f174>] hrtimer_cpu_notify+0xbc/0x240 which lock already depends on the new lock. This happens because we have the following code in kernel/hrtimer.c: migrate_hrtimers(int cpu) [...] old_base = &per_cpu(hrtimer_bases, cpu); new_base = &get_cpu_var(hrtimer_bases); [...] spin_lock(&new_base->lock); spin_lock(&old_base->lock); Which means the spinlocks are taken in an order which depends on which cpu gets shut down from which other cpu. Therefore lockdep complains that there might be an ABBA deadlock. Since migrate_hrtimers() gets only called on cpu hotplug it's safe to assume that it isn't executed concurrently on a The same problem exists in kernel/timer.c: migrate_timers(). As pointed out by Christian Borntraeger one possible solution to avoid the locking order complaints would be to make sure that the locks are always taken in the same order. E.g. by taking the lock of the cpu with the lower number first. To achieve this we introduce two new spinlock functions double_spin_lock and double_spin_unlock which lock or unlock two locks in a given order. Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: John Stultz <johnstul@us.ibm.com> Cc: Christian Borntraeger <cborntra@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | [PATCH] clocksource init adjustments (fix bug #7426)john stultz2007-03-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch resolves the issue found here: http://bugme.osdl.org/show_bug.cgi?id=7426 The basic summary is: Currently we register most of i386/x86_64 clocksources at module_init time. Then we enable clocksource selection at late_initcall time. This causes some problems for drivers that use gettimeofday for init calibration routines (specifically the es1968 driver in this case), where durring module_init, the only clocksource available is the low-res jiffies clocksource. This may cause slight calibration errors, due to the small sampling time used. It should be noted that drivers that require fine grained time may not function on architectures that do not have better then jiffies resolution timekeeping (there are a few). However, this does not discount the reasonable need for such fine-grained timekeeping at init time. Thus the solution here is to register clocksources earlier (ideally when the hardware is being initialized), and then we enable clocksource selection at fs_initcall (before device_initcall). This patch should probably get some testing time in -mm, since clocksource selection is one of the most important issues for correct timekeeping, and I've only been able to test this on a few of my own boxes. Signed-off-by: John Stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | [PATCH] sched: remove SMT niceCon Kolivas2007-03-05
|/ | | | | | | | | | | | | | | | | | | | | | | | | | Remove the SMT-nice feature which idles sibling cpus on SMT cpus to facilitiate nice working properly where cpu power is shared. The idling of cpus in the presence of runnable tasks is considered too fragile, easy to break with outside code, and the complexity of managing this system if an architecture comes along with many logical cores sharing cpu power will be unworkable. Remove the associated per_cpu_gain variable in sched_domains used only by this code. Also: The reason is that with dynticks enabled, this code breaks without yet further tweaks so dynticks brought on the rapid demise of this code. So either we tweak this code or kill it off entirely. It was Ingo's preference to kill it off. Either way this needs to happen for 2.6.21 since dynticks has gone in. Signed-off-by: Con Kolivas <kernel@kolivas.org> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] sched: fix SMT scheduler bugIngo Molnar2007-03-01
| | | | | | | | | | | | | | | | | | | | The SMT scheduler incorrectly skips kernel threads even if they are runnable (but they are preempted by a higher-prio user-space task which got SMT-delayed by an even higher-priority task running on a sibling CPU). Fix this for now by only doing the SMT-nice optimization if the to-be-delayed task is the only runnable task. (This should cover most of the real-life cases anyway.) This bug has been in the SMT scheduler since 2.6.17 or so, but has only been noticed now by the active check in the dynticks code. Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Michal Piotrowski <michal.k.k.piotrowski@gmail.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] fix section mismatch warning in lockdepSam Ravnborg2007-03-01
| | | | | | | | | | | | | | | | | | | | | lockdep_init() is marked __init but used in several places outside __init code. This causes following warnings: $ scripts/mod/modpost kernel/lockdep.o WARNING: kernel/built-in.o - Section mismatch: reference to .init.text:lockdep_init from .text.lockdep_init_map after 'lockdep_init_map' (at offset 0x105) WARNING: kernel/built-in.o - Section mismatch: reference to .init.text:lockdep_init from .text.lockdep_reset_lock after 'lockdep_reset_lock' (at offset 0x35) WARNING: kernel/built-in.o - Section mismatch: reference to .init.text:lockdep_init from .text.__lock_acquire after '__lock_acquire' (at offset 0xb2) The warnings are less obviously due to heavy inlining by gcc - this is not altered. Fix the section mismatch warnings by removing the __init marking, which seems obviously wrong. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] fix the SYSCTL=n compilationAdrian Bunk2007-03-01
| | | | | | | | | | | | | /home/bunk/linux/kernel-2.6/linux-2.6.20-mm2/kernel/sysctl.c:1411: error: conflicting types for 'register_sysctl_table' /home/bunk/linux/kernel-2.6/linux-2.6.20-mm2/include/linux/sysctl.h:1042: error: previous declaration of 'register_sysctl_table' was here make[2]: *** [kernel/sysctl.o] Error 1 Caused by commit 0b4d414714f0d2f922d39424b0c5c82ad900a381. Signed-off-by: Adrian Bunk <bunk@stusta.de> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] Fix posix-cpu-timer breakage caused by stale p->last_ran valueThomas Gleixner2007-03-01
| | | | | | | | | | | | | | | | | | | | Problem description at: http://bugzilla.kernel.org/show_bug.cgi?id=8048 Commit b18ec80396834497933d77b81ec0918519f4e2a7 [PATCH] sched: improve migration accuracy optimized the scheduler time calculations, but broke posix-cpu-timers. The problem is that the p->last_ran value is not updated after a context switch. So a subsequent call to current_sched_time() calculates with a stale p->last_ran value, i.e. accounts the full time, which the task was scheduled away. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] kernel-doc fixes for 2.6.20-git15 (non-drivers)Randy Dunlap2007-03-01
| | | | | | | | Fix kernel-doc warnings in 2.6.20-git15 (lib/, mm/, kernel/, include/). Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] update timekeeping_is_continuous commentDaniel Walker2007-03-01
| | | | | | Signed-off-by: Daniel Walker <dwalker@mvista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge master.kernel.org:/pub/scm/linux/kernel/git/kyle/parisc-2.6Linus Torvalds2007-02-26
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * master.kernel.org:/pub/scm/linux/kernel/git/kyle/parisc-2.6: (78 commits) [PARISC] Use symbolic last syscall in __NR_Linux_syscalls [PARISC] Add missing statfs64 and fstatfs64 syscalls Revert "[PARISC] Optimize TLB flush on SMP systems" [PARISC] Compat signal fixes for 64-bit parisc [PARISC] Reorder syscalls to match unistd.h Revert "[PATCH] make kernel/signal.c:kill_proc_info() static" [PARISC] fix sys_rt_sigqueueinfo [PARISC] fix section mismatch warnings in harmony sound driver [PARISC] do not export get_register/set_register [PARISC] add ENTRY()/ENDPROC() and simplify assembly of HP/UX emulation code [PARISC] convert to use CONFIG_64BIT instead of __LP64__ [PARISC] use CONFIG_64BIT instead of __LP64__ [PARISC] add ASM_EXCEPTIONTABLE_ENTRY() macro [PARISC] more ENTRY(), ENDPROC(), END() conversions [PARISC] fix ENTRY() and ENDPROC() for 64bit-parisc [PARISC] Fixes /proc/cpuinfo cache output on B160L [PARISC] implement standard ENTRY(), END() and ENDPROC() [PARISC] kill ENTRY_SYS_CPUS [PARISC] clean up debugging printks in smp.c [PARISC] factor syscall_restart code out of do_signal ... Fix conflict in include/linux/sched.h due to kill_proc_info() being made publicly available to PARISC again.
| * Revert "[PATCH] make kernel/signal.c:kill_proc_info() static"Matthew Wilcox2007-02-17
| | | | | | | | | | | | | | This reverts commit d3228a887cae75ef2b8b1211c31c539bef5a5698. DeBunk this code. We need it for compat_sys_rt_sigqueueinfo. Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
* | Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/tick-2.6Linus Torvalds2007-02-26
|\ \ | | | | | | | | | | | | | | | * master.kernel.org:/pub/scm/linux/kernel/git/davem/tick-2.6: [TICK] tick-common: Fix one-shot handling in tick_handle_periodic(). [TIME] tick-sched: Add missing asm/irq_regs.h include.
| * | [TICK] tick-common: Fix one-shot handling in tick_handle_periodic().David S. Miller2007-02-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When clockevents_program_event() is given an expire time in the past, it does not update dev->next_event, so this looping code would loop forever once the first in-the-past expiration time was used. Keep advancing "next" locally to fix this bug. Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
| * | [TIME] tick-sched: Add missing asm/irq_regs.h include.David S. Miller2007-02-26
| | | | | | | | | | | | | | | Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6Linus Torvalds2007-02-26
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6: Revert "Driver core: let request_module() send a /sys/modules/kmod/-uevent" Driver core: fix error by cleanup up symlinks properly make kernel/kmod.c:kmod_mk static power management: fix struct layout and docs power management: no valid states w/o pm_ops Driver core: more fallout from class_device changes for pcmcia sysfs: move struct sysfs_dirent to private header driver core: refcounting fix Driver core: remove class_device_rename
| * | | Revert "Driver core: let request_module() send a /sys/modules/kmod/-uevent"Greg Kroah-Hartman2007-02-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit c353c3fb0700a3c17ea2b0237710a184232ccd7f. It turns out that we end up with a loop trying to load the unix module and calling netfilter to do that. Will redo the patch later to not have this loop. Acked-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * | | make kernel/kmod.c:kmod_mk staticAdrian Bunk2007-02-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch makes the needlessly global struct kmod_mk static. Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>