- Sep 26, 2006
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Andi Kleen authored
- Remove unused all_contexts parameter No caller used it - Move skip argument into the structure (needed for followon patches) Cc: mingo@elte.hu Signed-off-by:Andi Kleen <ak@suse.de>
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Andi Kleen authored
This ports the algorithm from x86-64 (with improvements) to i386. Previously this only worked for frame pointer enabled kernels. But spinlocks have a very simple stack frame that can be manually analyzed. Do this. Signed-off-by: -
Andi Kleen authored
For NUMA optimization and some other algorithms it is useful to have a fast to get the current CPU and node numbers in user space. x86-64 added a fast way to do this in a vsyscall. This adds a generic syscall for other architectures to make it a generic portable facility. I expect some of them will also implement it as a faster vsyscall. The cache is an optimization for the x86-64 vsyscall optimization. Since what the syscall returns is an approximation anyways and user space often wants very fast results it can be cached for some time. The norma methods to get this information in user space are relatively slow The vsyscall is in a better position to manage the cache because it has direct access to a fast time stamp (jiffies). For the generic syscall optimization it doesn't help much, but enforce a valid argument to keep programs portable I only added an i386 syscall entry for now. Other architectures can follow as needed. AK: Also added some cleanups from Andrew Morton Signed-off-by: -
Don Zickus authored
To quote Alan Cox: The default Linux behaviour on an NMI of either memory or unknown is to continue operation. For many environments such as scientific computing it is preferable that the box is taken out and the error dealt with than an uncorrected parity/ECC error get propogated. A small number of systems do generate NMI's for bizarre random reasons such as power management so the default is unchanged. In other respects the new proc/sys entry works like the existing panic controls already in that directory. This is separate to the edac support - EDAC allows supported chipsets to handle ECC errors well, this change allows unsupported cases to at least panic rather than cause problems further down the line. Signed-off-by:
Don Zickus <dzickus@redhat.com> Signed-off-by:
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Don Zickus authored
Adds a new /proc/sys/kernel/nmi call that will enable/disable the nmi watchdog. Signed-off-by:
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Don Zickus authored
Removes the un/set_nmi_callback and reserve/release_lapic_nmi functions as they are no longer needed. The various subsystems are modified to register with the die_notifier instead. Also includes compile fixes by Andrew Morton. Signed-off-by:
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Ed Swierk authored
Invoking load_module() before param_sysfs_init() is called crashes in mod_sysfs_setup(), since the kset in module_subsys is not initialized yet. In my case, net-pf-1 is getting modprobed as a result of hotplug trying to create a UNIX socket. Calls to hotplug begin after the topology_init initcall. Another patch for the same symptom (module_subsys-initialize-earlier.patch) moves param_sysfs_init() to the subsys initcalls, but this is still not early enough in the boot process in some cases. In particular, topology_init() causes /sbin/hotplug to run, which requests net-pf-1 (the UNIX socket protocol) which can be compiled as a module. Moving param_sysfs_init() to the postcore initcalls fixes this particular race, but there might well be other cases where a usermodehelper causes a module to load earlier still. The patch makes load_module() return an error rather than crashing the kernel if invoked before module_subsys is initialized. Cc: Mark Huang <mlhuang@cs.princeton.edu> Cc: Greg KH <greg@kroah.com> Cc: <stable@kernel.org> Signed-off-by:
Andrew Morton <akpm@osdl.org> Signed-off-by:
Linus Torvalds <torvalds@osdl.org>
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- Sep 22, 2006
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Thomas Graf authored
Adds: nlmsg_get_pos() return current position in message nlmsg_trim() trim part of message nla_reserve_nohdr(skb, len) reserve room for an attribute w/o hdr nla_put_nohdr(skb, len, data) add attribute w/o hdr nla_find_nested() find attribute in nested attributes Fixes nlmsg_new() to take allocation flags and consider size. Signed-off-by:
Thomas Graf <tgraf@suug.ch> Signed-off-by:
David S. Miller <davem@davemloft.net>
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- Sep 19, 2006
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Ingo Molnar authored
while porting the -rt tree to 2.6.18-rc7 i noticed the following screaming-IRQ scenario on an SMP system: 2274 0Dn.:1 0.001ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.010ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.020ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.029ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.039ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.048ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.058ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.068ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.077ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.087ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) 2274 0Dn.:1 0.097ms: do_IRQ+0xc/0x103 <= (ret_from_intr+0x0/0xf) as it turns out, the bug is caused by handle_level_irq(), which if it races with another CPU already handling this IRQ, it _unmasks_ the IRQ line on the way out. This is not how 2.6.17 works, and we introduced this bug in one of the early genirq cleanups right before it went into -mm. (the bug was not in the genirq patchset for a long time, and we didnt notice the bug due to the lack of -rt rebase to the new genirq code. -rt, and hardirq-preemption in particular opens up such races much wider than anything else.) Signed-off-by:
Ingo Molnar <mingo@elte.hu> Signed-off-by:
Thomas Gleixner <tglx@linutronix.de> Acked-by:
Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by:
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- Sep 16, 2006
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Kenneth Lee authored
I think there is a bug in kmod.c: In __call_usermodehelper(), when kernel_thread(wait_for_helper, ...) return success, since wait_for_helper() might call complete() at any time, the sub_info should not be used any more. Normally wait_for_helper() take a long time to finish, you may not get problem for most of the case. But if you remove /sbin/modprobe, it may become easier for you to get a oop in khelper. Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by:
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Imre Deak authored
Fix a bug where the IRQ_PENDING flag is never cleared and the ISR is called endlessly without an actual interrupt. Signed-off-by:
Imre Deak <imre.deak@solidboot.com> Acked-by:
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- Sep 13, 2006
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Oleg Nesterov authored
rcu_do_batch() decrements rdp->qlen with irqs enabled. This is not good, it can also be modified by call_rcu() from interrupt. Decrement ->qlen once with irqs disabled, after a main loop. Signed-off-by:
Oleg Nesterov <oleg@tv-sign.ru> Cc: Dipankar Sarma <dipankar@in.ibm.com> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Signed-off-by:
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Ingo Molnar authored
Miles Lane reported the "BUG: MAX_STACK_TRACE_ENTRIES too low!" message, which means that during normal use his system produced enough lockdep events so that the 128-thousand entries stack-trace array got exhausted. Double the size of the array. Signed-off-by:
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- Sep 11, 2006
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Al Viro authored
add support for AUDIT_PERM predicate Signed-off-by:Al Viro <viro@zeniv.linux.org.uk>
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Amy Griffis authored
Make the audit message for implicit rule removal more informative. Make the rule update message consistent with other messages. Signed-off-by:
Amy Griffis <amy.griffis@hp.com> Signed-off-by:
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Amy Griffis authored
Add sanity checks for NULL audit_buffer consistent with other audit_log* routines. Signed-off-by:
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Steve Grubb authored
Hello, During some troubleshooting, I found that ppid was accidentally omitted from the legacy rule section. This resulted in EINVAL for any rule with ppid sent with AUDIT_ADD. Signed-off-by:
Steve Grubb <sgrubb@redhat.com> Signed-off-by:
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- Sep 08, 2006
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Thomas Gleixner authored
The current implementation of futex_lock_pi returns -ERESTART_RESTARTBLOCK in case that the lock operation has been interrupted by a signal. This results in a return of -EINTR to userspace in case there is an handler for the signal. This is wrong, because userspace expects that the lock function does not return in any case of signal delivery. This was not caught by my insufficient test case, but triggered a nasty userspace problem in an high load application scenario. Unfortunately also glibc does not check for this invalid return value. Using -ERSTARTNOINTR makes sure, that the interrupted syscall is restarted. The restart block related code can be safely removed, as the possible timeout argument is an absolute time value. Signed-off-by:
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- Sep 06, 2006
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Ingo Molnar authored
Remove an unintended console_verbose() side-effect from add_taint(). Signed-off-by:
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Pavel Machek authored
PAE + swsusp results in hard-to-debug crash about 50% of time during resume. Cause is known, fix needs to be ported from x86-64 (but we can't make it to 2.6.18, and I'd like this to be worked around in 2.6.18). Signed-off-by:
Pavel Machek <pavel@suse.cz> Signed-off-by:
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Jarek Poplawski authored
With CONFIG_SMP=y CONFIG_PREEMPT=y CONFIG_LOCKDEP=y CONFIG_DEBUG_LOCK_ALLOC=y # CONFIG_PROVE_LOCKING is not set spin_unlock_irqrestore() goes through lockdep but spin_lock_irqsave() doesn't. Apparently, bad things happen. Acked-by:
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- Sep 02, 2006
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Oleg Nesterov authored
It is not possible to find a sub-thread in ->children/->ptrace_children lists, ptrace_attach() does not allow to attach to sub-threads. Even if it was possible to ptrace the task from the same thread group, we can't allow to release ->group_leader while there are others (ptracer) threads in the same group. Signed-off-by:
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- Sep 01, 2006
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Henrik Kretzschmar authored
Adds the description of the parameters from handle_bad_irq(). Signed-off-by:
Henrik Kretzschmar <henne@nachtwindheim.de> Signed-off-by:
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Shailabh Nagar authored
Cleanup allocation and freeing of tsk->delays used by delay accounting. This solves two problems reported for delay accounting: 1. oops in __delayacct_blkio_ticks http://www.uwsg.indiana.edu/hypermail/linux/kernel/0608.2/1844.html Currently tsk->delays is getting freed too early in task exit which can cause a NULL tsk->delays to get accessed via reading of /proc/<tgid>/stats. The patch fixes this problem by freeing tsk->delays closer to when task_struct itself is freed up. As a result, it also eliminates the use of tsk->delays_lock which was only being used (inadequately) to safeguard access to tsk->delays while a task was exiting. 2. Possible memory leak in kernel/delayacct.c http://www.uwsg.indiana.edu/hypermail/linux/kernel/0608.2/1389.html The patch cleans up tsk->delays allocations after a bad fork which was missing earlier. The patch has been tested to fix the problems listed above and stress tested with rapid calls to delay accounting's taskstats command interface (which is the other path that can access the same data, besides the /proc interface causing the oops above). Signed-off-by:
Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Signed-off-by:
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- Aug 27, 2006
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Nicholas Piggin authored
cpuset_excl_nodes_overlap always returns 0 if current is exiting. This caused customer's systems to panic in the OOM killer when processes were having trouble getting memory for the final put_user in mm_release. Even though there were lots of processes to kill. Change to returning 1 in this case. This achieves parity with !CONFIG_CPUSETS case, and was observed to fix the problem. Signed-off-by:
Nick Piggin <npiggin@suse.de> Acked-by:
Paul Jackson <pj@sgi.com> Signed-off-by:
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Paul Jackson authored
Change the list of cpus allowed to tasks in the top (root) cpuset to dynamically track what cpus are online, using a CPU hotplug notifier. Make this top cpus file read-only. On systems that have cpusets configured in their kernel, but that aren't actively using cpusets (for some distros, this covers the majority of systems) all tasks end up in the top cpuset. If that system does support CPU hotplug, then these tasks cannot make use of CPUs that are added after system boot, because the CPUs are not allowed in the top cpuset. This is a surprising regression over earlier kernels that didn't have cpusets enabled. In order to keep the behaviour of cpusets consistent between systems actively making use of them and systems not using them, this patch changes the behaviour of the 'cpus' file in the top (root) cpuset, making it read only, and making it automatically track the value of cpu_online_map. Thus tasks in the top cpuset will have automatic use of hot plugged CPUs allowed by their cpuset. Thanks to Anton Blanchard and Nathan Lynch for reporting this problem, driving the fix, and earlier versions of this patch. Signed-off-by:
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Yingchao Zhou authored
An up() is called in kernel/stop_machine.c on failure, and also in the caller (unconditionally). Signed-off-by:
Zhou Yingchao <yingchao.zhou@gmail.com> Cc: <stable@kernel.org> Signed-off-by:
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Oleg Nesterov authored
futex_find_get_task: if (p->state == EXIT_ZOMBIE || p->exit_state == EXIT_ZOMBIE) return NULL; I can't understand this. First, p->state can't be EXIT_ZOMBIE. The ->exit_state check looks strange too. Sub-threads or tasks whose ->parent ignores SIGCHLD go directly to EXIT_DEAD state (I am ignoring a ptrace case). Why EXIT_DEAD tasks should be ok? Yes, EXIT_ZOMBIE is more important (a task may stay zombie for a long time), but this doesn't mean we should explicitely ignore other EXIT_XXX states. Signed-off-by:
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Oleg Nesterov authored
sched_setscheduler() looks at ->signal->rlim[]. It is unsafe do dereference ->signal unless tasklist_lock or ->siglock is held (or p == current). We pin the task structure, but this can't prevent from release_task()->__exit_signal() which sets ->signal = NULL. Restore tasklist_lock across the setscheduler call. Signed-off-by:
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- Aug 14, 2006
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Andrew Morton authored
Use a private lock instead. It protects all per-cpu data structures in workqueue.c, including the workqueues list. Fix a bug in schedule_on_each_cpu(): it was forgetting to lock down the per-cpu resources. Unfixed long-standing bug: if someone unplugs the CPU identified by `singlethread_cpu' the kernel will get very sick. Cc: Dave Jones <davej@codemonkey.org.uk> Signed-off-by:
Greg Kroah-Hartman <gregkh@suse.de>
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John Stultz authored
We found this issue last week w/ the -RT kernel, but it seems the same issue is in mainline as well. Basically it is possible for futex_unlock_pi to return without actually freeing the lock. This is due to buggy logic in the use of futex_handle_fault() and its attempt argument in a failure case. Looking at futex.c the logic is as follows: 1) In futex_unlock_pi() we start w/ ret=0 and we go down to the first futex_atomic_cmpxchg_inatomic(), where we find uval==-EFAULT. We then jump to the pi_faulted label. 2) From pi_faulted: We increment attempt, unlock the sem and hit the retry label. 3) From the retry label, with ret still zero, we again hit EFAULT on the first futex_atomic_cmpxchg_inatomic(), and again goto the pi_faulted label. 4) Again from pi_faulted: we increment attempt and enter the conditional, where we call futex_handle_fault. 5) futex_handle_fault fails, and we goto the out_unlock_release_sem label. 6) From out_unlock_release_sem we return, and since ret is still zero, we return without error, while never actually unlocking the lock. Issue #1: at the first futex_atomic_cmpxchg_inatomic() we should probably be setting ret=-EFAULT before jumping to pi_faulted: However in our case this doesn't really affect anything, as the glibc we're using ignores the error value from futex_unlock_pi(). Issue #2: Look at futex_handle_fault(), its first conditional will return -EFAULT if attempt is >= 2. However, from the "if(attempt++) futex_handle_fault(attempt)" logic above, we'll *never* call futex_handle_fault when attempt is less then two. So we never get a chance to even try to fault the page in. The following patch addresses these two issues by 1) Always setting ret to -EFAULT if futex_handle_fault fails, and 2) Removing the = in futex_handle_fault's (attempt >= 2) check. I'm really not sure this is the right fix, but wanted to bring it up so folks knew the issue is alive and well in the current -git tree. From looking at the git logs the logic was first introduced (then later copied to other places) in the following commit almost a year ago: http://www.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=4732efbeb997189d9f9b04708dc26bf8613ed721;hp=5b039e681b8c5f30aac9cc04385cc94be45d0823 Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Ingo Molnar <mingo@elte.hu> Acked-by:
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Kirill Korotaev authored
sys_getppid() optimization can access a freed memory. On kernels with DEBUG_SLAB turned ON, this results in Oops. As Dave Hansen noted, this optimization is also unsafe for memory hotplug. So this patch always takes the lock to be safe. [oleg@tv-sign.ru: simplifications] Signed-off-by:
Kirill Korotaev <dev@openvz.org> Cc: <stable@kernel.org> Cc: Dave Hansen <haveblue@us.ibm.com> Signed-off-by:
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Andrew Morton authored
kernel/panic.c: In function 'add_taint': kernel/panic.c:176: warning: implicit declaration of function 'debug_locks_off' Cc: Andi Kleen <ak@muc.de> Signed-off-by:
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Jan Blunck authored
The percpu variable is used incorrectly in switch_hrtimer_base(). Signed-off-by:
Jan Blunck <jblunck@suse.de> Acked-by:
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- Aug 06, 2006
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Thomas Gleixner authored
The recent fixups in futex.c need to be applied to futex_compat.c too. Fixes a hang reported by Olaf. Signed-off-by:
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KAMEZAWA Hiroyuki authored
find_next_system_ram() is used to find available memory resource at onlining newly added memory. This patch fixes following problem. find_next_system_ram() cannot catch this case. Resource: (start)-------------(end) Section : (start)-------------(end) Signed-off-by:
KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Keith Mannthey <kmannth@gmail.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Dave Hansen <haveblue@us.ibm.com> Signed-off-by:
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KAMEZAWA Hiroyuki authored
find_next_system_ram() returns valid memory range which meets requested area, only used by memory-hot-add. This function always rewrite requested resource even if returned area is not fully fit in requested one. And sometimes the returnd resource is larger than requested area. This annoyes the caller. This patch changes the returned value to fit in requested area. Signed-off-by:
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Antonino A. Daplas authored
Reported by: Dave Jones Whilst printk'ing to both console and serial console, I got this... (2.6.18rc1) BUG: sleeping function called from invalid context at kernel/sched.c:4438 in_atomic():0, irqs_disabled():1 Call Trace: [<ffffffff80271db8>] show_trace+0xaa/0x23d [<ffffffff80271f60>] dump_stack+0x15/0x17 [<ffffffff8020b9f8>] __might_sleep+0xb2/0xb4 [<ffffffff8029232e>] __cond_resched+0x15/0x55 [<ffffffff80267eb8>] cond_resched+0x3b/0x42 [<ffffffff80268c64>] console_conditional_schedule+0x12/0x14 [<ffffffff80368159>] fbcon_redraw+0xf6/0x160 [<ffffffff80369c58>] fbcon_scroll+0x5d9/0xb52 [<ffffffff803a43c4>] scrup+0x6b/0xd6 [<ffffffff803a4453>] lf+0x24/0x44 [<ffffffff803a7ff8>] vt_console_print+0x166/0x23d [<ffffffff80295528>] __call_console_drivers+0x65/0x76 [<ffffffff80295597>] _call_console_drivers+0x5e/0x62 [<ffffffff80217e3f>] release_console_sem+0x14b/0x232 [<ffffffff8036acd6>] fb_flashcursor+0x279/0x2a6 [<ffffffff80251e3f>] run_workqueue+0xa8/0xfb [<ffffffff8024e5e0>] worker_thread+0xef/0x122 [<ffffffff8023660f>] kthread+0x100/0x136 [<ffffffff8026419e>] child_rip+0x8/0x12 This can occur when release_console_sem() is called but the log buffer still has contents that need to be flushed. The console drivers are called while the console_may_schedule flag is still true. The might_sleep() is triggered when fbcon calls console_conditional_schedule(). Fix by setting console_may_schedule to zero earlier, before the call to the console drivers. Signed-off-by:
Antonino Daplas <adaplas@pol.net> Signed-off-by:
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Chuck Ebbert authored
When delivering PTRACE_EVENT_VFORK_DONE, provide pid of the child process when tracer calls ptrace(PTRACE_GETEVENTMSG). This is already (accidentally) available when the tracer is tracing VFORK in addition to VFORK_DONE. Signed-off-by:
Chuck Ebbert <76306.1226@compuserve.com> Cc: Daniel Jacobowitz <dan@debian.org> Cc: Albert Cahalan <acahalan@gmail.com> Cc: Roland McGrath <roland@redhat.com> Signed-off-by:
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Christian Borntraeger authored
This patch adds a barrier() in futex unqueue_me to avoid aliasing of two pointers. On my s390x system I saw the following oops: Unable to handle kernel pointer dereference at virtual kernel address 0000000000000000 Oops: 0004 [#1] CPU: 0 Not tainted Process mytool (pid: 13613, task: 000000003ecb6ac0, ksp: 00000000366bdbd8) Krnl PSW : 0704d00180000000 00000000003c9ac2 (_spin_lock+0xe/0x30) Krnl GPRS: 00000000ffffffff 000000003ecb6ac0 0000000000000000 0700000000000000 0000000000000000 0000000000000000 000001fe00002028 00000000000c091f 000001fe00002054 000001fe00002054 0000000000000000 00000000366bddc0 00000000005ef8c0 00000000003d00e8 0000000000144f91 00000000366bdcb8 Krnl Code: ba 4e 20 00 12 44 b9 16 00 3e a7 84 00 08 e3 e0 f0 88 00 04 Call Trace: ([<0000000000144f90>] unqueue_me+0x40/0xe4) [<0000000000145a0c>] do_futex+0x33c/0xc40 [<000000000014643e>] sys_futex+0x12e/0x144 [<000000000010bb00>] sysc_noemu+0x10/0x16 [<000002000003741c>] 0x2000003741c The code in question is: static int unqueue_me(struct futex_q *q) { int ret = 0; spinlock_t *lock_ptr; /* In the common case we don't take the spinlock, which is nice. */ retry: lock_ptr = q->lock_ptr; if (lock_ptr != 0) { spin_lock(lock_ptr); /* * q->lock_ptr can change between reading it and * spin_lock(), causing us to take the wrong lock. This * corrects the race condition. [...] and my compiler (gcc 4.1.0) makes the following out of it: 00000000000003c8 <unqueue_me>: 3c8: eb bf f0 70 00 24 stmg %r11,%r15,112(%r15) 3ce: c0 d0 00 00 00 00 larl %r13,3ce <unqueue_me+0x6> 3d0: R_390_PC32DBL .rodata+0x2a 3d4: a7 f1 1e 00 tml %r15,7680 3d8: a7 84 00 01 je 3da <unqueue_me+0x12> 3dc: b9 04 00 ef lgr %r14,%r15 3e0: a7 fb ff d0 aghi %r15,-48 3e4: b9 04 00 b2 lgr %r11,%r2 3e8: e3 e0 f0 98 00 24 stg %r14,152(%r15) 3ee: e3 c0 b0 28 00 04 lg %r12,40(%r11) /* write q->lock_ptr in r12 */ 3f4: b9 02 00 cc ltgr %r12,%r12 3f8: a7 84 00 4b je 48e <unqueue_me+0xc6> /* if r12 is zero then jump over the code.... */ 3fc: e3 20 b0 28 00 04 lg %r2,40(%r11) /* write q->lock_ptr in r2 */ 402: c0 e5 00 00 00 00 brasl %r14,402 <unqueue_me+0x3a> 404: R_390_PC32DBL _spin_lock+0x2 /* use r2 as parameter for spin_lock */ So the code becomes more or less: if (q->lock_ptr != 0) spin_lock(q->lock_ptr) instead of if (lock_ptr != 0) spin_lock(lock_ptr) Which caused the oops from above. After adding a barrier gcc creates code without this problem: [...] (the same) 3ee: e3 c0 b0 28 00 04 lg %r12,40(%r11) 3f4: b9 02 00 cc ltgr %r12,%r12 3f8: b9 04 00 2c lgr %r2,%r12 3fc: a7 84 00 48 je 48c <unqueue_me+0xc4> 400: c0 e5 00 00 00 00 brasl %r14,400 <unqueue_me+0x38> 402: R_390_PC32DBL _spin_lock+0x2 As a general note, this code of unqueue_me seems a bit fishy. The retry logic of unqueue_me only works if we can guarantee, that the original value of q->lock_ptr is always a spinlock (Otherwise we overwrite kernel memory). We know that q->lock_ptr can change. I dont know what happens with the original spinlock, as I am not an expert with the futex code. Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Acked-by:Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@timesys.com> Signed-off-by:
Christian Borntraeger <borntrae@de.ibm.com> Signed-off-by:
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