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2012-03-12Merge tag 'v3.3-rc7' into gpio/nextGrant Likely
Linux 3.3-rc7. Merged into the gpio branch to pick up gpio bugfixes already in mainline before queueing up move v3.4 patches
2012-03-07Revert "CPU hotplug, cpusets, suspend: Don't touch cpusets during ↵Linus Torvalds
suspend/resume" This reverts commit 8f2f748b0656257153bcf0941df8d6060acc5ca6. It causes some odd regression that we have not figured out, and it's too late in the -rc series to try to figure it out now. As reported by Konstantin Khlebnikov, it causes consistent hangs on his laptop (Thinkpad x220: 2x cores + HT). They can be avoided by adding calls to "rebuild_sched_domains();" in cpuset_cpu_[in]active() for the CPU_{ONLINE/DOWN_FAILED/DOWN_PREPARE}_FROZEN cases, but it's not at all clear why, and it makes no sense. Konstantin's config doesn't even have CONFIG_CPUSETS enabled, just to make things even more interesting. So it's not the cpusets, it's just the scheduling domains. So until this is understood, revert. Bisected-reported-and-tested-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-06genirq: Clear action->thread_mask if IRQ_ONESHOT is not setThomas Gleixner
Xommit ac5637611(genirq: Unmask oneshot irqs when thread was not woken) fails to unmask when a !IRQ_ONESHOT threaded handler is handled by handle_level_irq. This happens because thread_mask is or'ed unconditionally in irq_wake_thread(), but for !IRQ_ONESHOT interrupts never cleared. So the check for !desc->thread_active fails and keeps the interrupt disabled. Keep the thread_mask zero for !IRQ_ONESHOT interrupts. Document the thread_mask magic while at it. Reported-and-tested-by: Sven Joachim <svenjoac@gmx.de> Reported-and-tested-by: Stefan Lippers-Hollmann <s.l-h@gmx.de> Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05hung_task: fix the broken rcu_lock_break() logicOleg Nesterov
check_hung_uninterruptible_tasks()->rcu_lock_break() introduced by "softlockup: check all tasks in hung_task" commit ce9dbe24 looks absolutely wrong. - rcu_lock_break() does put_task_struct(). If the task has exited it is not safe to even read its ->state, nothing protects this task_struct. - The TASK_DEAD checks are wrong too. Contrary to the comment, we can't use it to check if the task was unhashed. It can be unhashed without TASK_DEAD, or it can be valid with TASK_DEAD. For example, an autoreaping task can do release_task(current) long before it sets TASK_DEAD in do_exit(). Or, a zombie task can have ->state == TASK_DEAD but release_task() was not called, and in this case we must not break the loop. Change this code to check pid_alive() instead, and do this before we drop the reference to the task_struct. Note: while_each_thread() under rcu_read_lock() is not really safe, it can livelock. This will be fixed later, but fortunately in this case the "max_count" logic saves us anyway. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Mandeep Singh Baines <msb@google.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05vfork: kill PF_STARTINGOleg Nesterov
Previously it was (ab)used by utrace. Then it was wrongly used by the scheduler code. Currently it is not used, kill it before it finds the new erroneous user. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05coredump_wait: don't call complete_vfork_done()Oleg Nesterov
Now that CLONE_VFORK is killable, coredump_wait() no longer needs complete_vfork_done(). zap_threads() should find and kill all tasks with the same ->mm, this includes our parent if ->vfork_done is set. mm_release() becomes the only caller, unexport complete_vfork_done(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05vfork: make it killableOleg Nesterov
Make vfork() killable. Change do_fork(CLONE_VFORK) to do wait_for_completion_killable(). If it fails we do not return to the user-mode and never touch the memory shared with our child. However, in this case we should clear child->vfork_done before return, we use task_lock() in do_fork()->wait_for_vfork_done() and complete_vfork_done() to serialize with each other. Note: now that we use task_lock() we don't really need completion, we could turn task->vfork_done into "task_struct *wake_up_me" but this needs some complications. NOTE: this and the next patches do not affect in-kernel users of CLONE_VFORK, kernel threads run with all signals ignored including SIGKILL/SIGSTOP. However this is obviously the user-visible change. Not only a fatal signal can kill the vforking parent, a sub-thread can do execve or exit_group() and kill the thread sleeping in vfork(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05vfork: introduce complete_vfork_done()Oleg Nesterov
No functional changes. Move the clear-and-complete-vfork_done code into the new trivial helper, complete_vfork_done(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05kprobes: return proper error code from register_kprobe()Prashanth Nageshappa
register_kprobe() aborts if the address of the new request falls in a prohibited area (such as ftrace pouch, __kprobes annotated functions, non-kernel text addresses, jump label text). We however don't return the right error on this abort, resulting in a silent failure - incorrect adding/reporting of kprobes ('perf probe do_fork+18' or 'perf probe mcount' for instance). In V2 we are incorporating Masami Hiramatsu's feedback. This patch fixes it by returning -EINVAL upon failure. While we are here, rename the label used for exit to be more appropriate. Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Signed-off-by: Prashanth K Nageshappa <prashanth@linux.vnet.ibm.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Jason Baron <jbaron@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-05kmsg_dump: don't run on non-error paths by defaultMatthew Garrett
Since commit 04c6862c055f ("kmsg_dump: add kmsg_dump() calls to the reboot, halt, poweroff and emergency_restart paths"), kmsg_dump() gets run on normal paths including poweroff and reboot. This is less than ideal given pstore implementations that can only represent single backtraces, since a reboot may overwrite a stored oops before it's been picked up by userspace. In addition, some pstore backends may have low performance and provide a significant delay in reboot as a result. This patch adds a printk.always_kmsg_dump kernel parameter (which can also be changed from userspace). Without it, the code will only be run on failure paths rather than on normal paths. The option can be enabled in environments where there's a desire to attempt to audit whether or not a reboot was cleanly requested or not. Signed-off-by: Matthew Garrett <mjg@redhat.com> Acked-by: Seiji Aguchi <seiji.aguchi@hds.com> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Marco Stornelli <marco.stornelli@gmail.com> Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Don Zickus <dzickus@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-02Merge branches 'core-urgent-for-linus', 'perf-urgent-for-linus' and ↵Linus Torvalds
'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pulling latest branches from Ingo: * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: memblock: Fix size aligning of memblock_alloc_base_nid() * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf probe: Ensure offset provided is not greater than function length without DWARF info too perf tools: Ensure comm string is properly terminated perf probe: Ensure offset provided is not greater than function length perf evlist: Return first evsel for non-sample event on old kernel perf/hwbp: Fix a possible memory leak * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: CPU hotplug, cpusets, suspend: Don't touch cpusets during suspend/resume
2012-02-28perf/hwbp: Fix a possible memory leakNamhyung Kim
If kzalloc() for TYPE_DATA failed on a given cpu, previous chunk of TYPE_INST will be leaked. Fix it. Thanks to Peter Zijlstra for suggesting this better solution. It should work as long as the initial value of the region is all 0's and that's the case of static (per-cpu) memory allocation. Signed-off-by: Namhyung Kim <namhyung.kim@lge.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Link: http://lkml.kernel.org/r/1330391978-28070-1-git-send-email-namhyung.kim@lge.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-27Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/events: Revert trace_sched_stat_sleeptime()
2012-02-27Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq: Handle pending irqs in irq_startup() genirq: Unmask oneshot irqs when thread was not woken
2012-02-27CPU hotplug, cpusets, suspend: Don't touch cpusets during suspend/resumeSrivatsa S. Bhat
Currently, during CPU hotplug, the cpuset callbacks modify the cpusets to reflect the state of the system, and this handling is asymmetric. That is, upon CPU offline, that CPU is removed from all cpusets. However when it comes back online, it is put back only to the root cpuset. This gives rise to a significant problem during suspend/resume. During suspend, we offline all non-boot cpus and during resume we online them back. Which means, after a resume, all cpusets (except the root cpuset) will be restricted to just one single CPU (the boot cpu). But the whole point of suspend/resume is to restore the system to a state which is as close as possible to how it was before suspend. So to fix this, don't touch cpusets during suspend/resume. That is, modify the cpuset-related CPU hotplug callback to just ignore CPU hotplug when it is initiated as part of the suspend/resume sequence. Reported-by: Prashanth Nageshappa <prashanth@linux.vnet.ibm.com> Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/4F460D7B.1020703@linux.vnet.ibm.com Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-24epoll: introduce POLLFREE to flush ->signalfd_wqh before kfree()Oleg Nesterov
This patch is intentionally incomplete to simplify the review. It ignores ep_unregister_pollwait() which plays with the same wqh. See the next change. epoll assumes that the EPOLL_CTL_ADD'ed file controls everything f_op->poll() needs. In particular it assumes that the wait queue can't go away until eventpoll_release(). This is not true in case of signalfd, the task which does EPOLL_CTL_ADD uses its ->sighand which is not connected to the file. This patch adds the special event, POLLFREE, currently only for epoll. It expects that init_poll_funcptr()'ed hook should do the necessary cleanup. Perhaps it should be defined as EPOLLFREE in eventpoll. __cleanup_sighand() is changed to do wake_up_poll(POLLFREE) if ->signalfd_wqh is not empty, we add the new signalfd_cleanup() helper. ep_poll_callback(POLLFREE) simply does list_del_init(task_list). This make this poll entry inconsistent, but we don't care. If you share epoll fd which contains our sigfd with another process you should blame yourself. signalfd is "really special". I simply do not know how we can define the "right" semantics if it used with epoll. The main problem is, epoll calls signalfd_poll() once to establish the connection with the wait queue, after that signalfd_poll(NULL) returns the different/inconsistent results depending on who does EPOLL_CTL_MOD/signalfd_read/etc. IOW: apart from sigmask, signalfd has nothing to do with the file, it works with the current thread. In short: this patch is the hack which tries to fix the symptoms. It also assumes that nobody can take tasklist_lock under epoll locks, this seems to be true. Note: - we do not have wake_up_all_poll() but wake_up_poll() is fine, poll/epoll doesn't use WQ_FLAG_EXCLUSIVE. - signalfd_cleanup() uses POLLHUP along with POLLFREE, we need a couple of simple changes in eventpoll.c to make sure it can't be "lost". Reported-by: Maxime Bizon <mbizon@freebox.fr> Cc: <stable@kernel.org> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-24irq_domain/mips: Allow irq_domain on MIPSGrant Likely
This patch makes IRQ_DOMAIN usable on MIPS. It uses an ugly workaround to preserve current behaviour so that MIPS has time to add irq_domain registration to the irq controller drivers. The workaround will be removed in Linux v3.6 Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mips@linux-mips.org
2012-02-22sched/events: Revert trace_sched_stat_sleeptime()Peter Zijlstra
Commit 1ac9bc69 ("sched/tracing: Add a new tracepoint for sleeptime") added a new sched:sched_stat_sleeptime tracepoint. It's broken: the first sample we get on a task might be bad because of a stale sleep_start value that wasn't reset at the last task switch because the tracepoint was not active. It also breaks the existing schedstat samples due to the side effects of: - se->statistics.sleep_start = 0; ... - se->statistics.block_start = 0; Nor do I see means to fix it without adding overhead to the scheduler fast path, which I'm not willing to for the sake of redundant instrumentation. Most importantly, sleep time information can already be constructed by tracing context switches and wakeups, and taking the timestamp difference between the schedule-out, the wakeup and the schedule-in. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrew Vagin <avagin@openvz.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Link: http://lkml.kernel.org/n/tip-pc4c9qhl8q6vg3bs4j6k0rbd@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-20Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Assorted fixes, sat in -next for a week or so... * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: ocfs2: deal with wraparounds of i_nlink in ocfs2_rename() vfs: fix compat_sys_stat() handling of overflows in st_nlink quota: Fix deadlock with suspend and quotas vfs: Provide function to get superblock and wait for it to thaw vfs: fix panic in __d_lookup() with high dentry hashtable counts autofs4 - fix lockdep splat in autofs vfs: fix d_inode_lookup() dentry ref leak
2012-02-16irq_domain: constify irq_domain_opsGrant Likely
Make irq_domain_ops pointer a constant to make it safer for multiple instances to share the same ops pointer and change the irq_domain code so that it does not modify the ops. v4: Fix mismatched type reference in powerpc code Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Milton Miller <miltonm@bga.com> Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16irq_domain: Create common xlate functions that device drivers can useGrant Likely
Rather than having each interrupt controller driver creating its own barely unique .xlate function for irq_domain, create a library of translators which any driver can use directly. v5: - Remove irq_domain_xlate_pci(). It was incorrect. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Mark Salter <msalter@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Milton Miller <miltonm@bga.com> Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16irq_domain: Remove irq_domain_add_simple()Grant Likely
irq_domain_add_simple() was a stop-gap measure until complete irq_domain support was complete. This patch removes the irq_domain_add_simple() interface. This patch also drops the explicit irq_domain initialization performed by the mach-versatile code because the versatile interrupt controller already has irq_domain support built into it. This was a bug that was hanging around quietly for a while, but with the full irq_domain which actually verifies that irq_domain ranges are available it would cause the registration to fail and the system wouldn't boot. v4: Fixed number of irqs in mx5 gpio code v2: Updated to pass in host_data pointer on irq_domain allocation. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Milton Miller <miltonm@bga.com> Cc: Russell King <linux@arm.linux.org.uk> Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16irq_domain: Remove 'new' irq_domain in favour of the ppc oneGrant Likely
This patch removes the simplistic implementation of irq_domains and enables the powerpc infrastructure for all irq_domain users. The powerpc infrastructure includes support for complex mappings between Linux and hardware irq numbers, and can manage allocation of irq_descs. This patch also converts the few users of irq_domain_add()/irq_domain_del() to call irq_domain_add_legacy() instead. v3: Fix bug that set up too many irqs in translation range. v2: Fix removal of irq_alloc_descs() call in gic driver Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Milton Miller <miltonm@bga.com> Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16irq_domain: Add support for base irq and hwirq in legacy mappingsGrant Likely
Add support for a legacy mapping where irq = (hwirq - first_hwirq + first_irq) so that a controller driver can allocate a fixed range of irq_descs and use a simple calculation to translate back and forth between linux and hw irq numbers. This is needed to use an irq_domain with many of the ARM interrupt controller drivers that manage their own irq_desc allocations. Ultimately the goal is to migrate those drivers to use the linear revmap, but doing it this way allows each driver to be converted separately which makes the migration path easier. This patch generalizes the IRQ_DOMAIN_MAP_LEGACY method to use (first_irq-first_hwirq) as the offset between hwirq and linux irq number, and adds checks to make sure that the hwirq number does not exceed range assigned to the controller. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Milton Miller <miltonm@bga.com> Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16irq_domain: Replace irq_alloc_host() with revmap-specific initializersGrant Likely
Each revmap type has different arguments for setting up the revmap. This patch splits up the generator functions so that each revmap type can do its own setup and the user doesn't need to keep track of how each revmap type handles the arguments. This patch also adds a host_data argument to the generators. There are cases where the host_data pointer will be needed before the function returns. ie. the legacy map calls the .map callback for each irq before returning. v2: - Add void *host_data argument to irq_domain_add_*() functions - fixed failure to compile - Moved IRQ_DOMAIN_MAP_* defines into irqdomain.c Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Milton Miller <miltonm@bga.com> Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16irq_domain: Remove references to old irq_host namesGrant Likely
No functional changes. Replaces non-exported references to 'host' with domain. Does not change any symbol names referenced by other .c files. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Milton Miller <miltonm@bga.com> Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16irq_domain: remove NO_IRQ from irq domain codeGrant Likely
zero always means no irq when using irq domains. Get rid of the NO_IRQ references. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Milton Miller <miltonm@bga.com> Tested-by: Olof Johansson <olof@lixom.net>
2012-02-16irq_domain: Move irq_domain code from powerpc to kernel/irqGrant Likely
This patch only moves the code. It doesn't make any changes, and the code is still only compiled for powerpc. Follow-on patches will generalize the code for other architectures. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Milton Miller <miltonm@bga.com> Tested-by: Olof Johansson <olof@lixom.net>
2012-02-15genirq: Handle pending irqs in irq_startup()Thomas Gleixner
An interrupt might be pending when irq_startup() is called, but the startup code does not invoke the resend logic. In some cases this prevents the device from issuing another interrupt which renders the device non functional. Call the resend function in irq_startup() to keep things going. Reported-and-tested-by: Russell King <rmk+kernel@arm.linux.org.uk> Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-02-15genirq: Unmask oneshot irqs when thread was not wokenThomas Gleixner
When the primary handler of an interrupt which is marked IRQ_ONESHOT returns IRQ_HANDLED or IRQ_NONE, then the interrupt thread is not woken and the unmask logic of the interrupt line is never invoked. This keeps the interrupt masked forever. This was not noticed as most IRQ_ONESHOT users wake the thread unconditionally (usually because they cannot access the underlying device from hard interrupt context). Though this behaviour was nowhere documented and not necessarily intentional. Some drivers can avoid the thread wakeup in certain cases and run into the situation where the interrupt line s kept masked. Handle it gracefully. Reported-and-tested-by: Lothar Wassmann <lw@karo-electronics.de> Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2012-02-14irq_domain: Make irq_domain structure match powerpc's irq_hostGrant Likely
Part of the series to unify the irq remapping mechanisms in the kernel. A follow up patch will copy the powerpc implementation into kernel/irq/irqdomain.c, which will be a lot easier if the structures are identical. Where they differ, I've chose to use the powerpc names since there is a lot more code using those names. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Milton Miller <miltonm@bga.com> Tested-by: Olof Johansson <olof@lixom.net>
2012-02-14irq_domain: Be less verboseGrant Likely
irq_domain printk's too much. Drop some output. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Thomas Gleixner <tglx@linutronix.de> Tested-by: Olof Johansson <olof@lixom.net>
2012-02-13vfs: fix panic in __d_lookup() with high dentry hashtable countsDimitri Sivanich
When the number of dentry cache hash table entries gets too high (2147483648 entries), as happens by default on a 16TB system, use of a signed integer in the dcache_init() initialization loop prevents the dentry_hashtable from getting initialized, causing a panic in __d_lookup(). Fix this in dcache_init() and similar areas. Signed-off-by: Dimitri Sivanich <sivanich@sgi.com> Acked-by: David S. Miller <davem@davemloft.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-02-13Merge tag 'for-linus' of git://github.com/rustyrussell/linuxLinus Torvalds
* tag 'for-linus' of git://github.com/rustyrussell/linux: module: fix broken isapnp handling in file2alias module: make module param bint handle nul value
2012-02-14module: make module param bint handle nul valueDave Young
Allow bint param accept nul values, just do same as bool param. Signed-off-by: Dave Young <dyoung@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-02-11Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds
Says Jens: "Time to push off some of the pending items. I really wanted to wait until we had the regression nailed, but alas it's not quite there yet. But I'm very confident that it's "just" a missing expire on exit, so fix from Tejun should be fairly trivial. I'm headed out for a week on the slopes. - Killing the barrier part of mtip32xx. It doesn't really support barriers, and it doesn't need them (writes are fully ordered). - A few fixes from Dan Carpenter, preventing overflows of integer multiplication. - A fixup for loop, fixing a previous commit that didn't quite solve the partial read problem from Dave Young. - A bio integer overflow fix from Kent Overstreet. - Improvement/fix of the door "keep locked" part of the cdrom shared code from Paolo Benzini. - A few cfq fixes from Shaohua Li. - A fix for bsg sysfs warning when removing a file it did not create from Stanislaw Gruszka. - Two fixes for floppy from Vivek, preventing a crash. - A few block core fixes from Tejun. One killing the over-optimized ioc exit path, cleaning that up nicely. Two others fixing an oops on elevator switch, due to calling into the scheduler merge check code without holding the queue lock." * 'for-linus' of git://git.kernel.dk/linux-block: block: fix lockdep warning on io_context release put_io_context() relay: prevent integer overflow in relay_open() loop: zero fill bio instead of return -EIO for partial read bio: don't overflow in bio_get_nr_vecs() floppy: Fix a crash during rmmod floppy: Cleanup disk->queue before caling put_disk() if add_disk() was never called cdrom: move shared static to cdrom_device_info bsg: fix sysfs link remove warning block: don't call elevator callbacks for plug merges block: separate out blk_rq_merge_ok() and blk_try_merge() from elevator functions mtip32xx: removed the irrelevant argument of mtip_hw_submit_io() and the unused member of struct driver_data block: strip out locking optimization in put_io_context() cdrom: use copy_to_user() without the underscores block: fix ioc locking warning block: fix NULL icq_cache reference block,cfq: change code order
2012-02-10Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf: Fix double start/stop in x86_pmu_start() perf evsel: Fix an issue where perf report fails to show the proper percentage perf tools: Fix prefix matching for kernel maps perf tools: Fix perf stack to non executable on x86_64 perf: Remove deprecated WARN_ON_ONCE()
2012-02-10relay: prevent integer overflow in relay_open()Dan Carpenter
"subbuf_size" and "n_subbufs" come from the user and they need to be capped to prevent an integer overflow. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: stable@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-02-07perf: Fix double start/stop in x86_pmu_start()Stephane Eranian
The following patch fixes a bug introduced by the following commit: e050e3f0a71b ("perf: Fix broken interrupt rate throttling") The patch caused the following warning to pop up depending on the sampling frequency adjustments: ------------[ cut here ]------------ WARNING: at arch/x86/kernel/cpu/perf_event.c:995 x86_pmu_start+0x79/0xd4() It was caused by the following call sequence: perf_adjust_freq_unthr_context.part() { stop() if (delta > 0) { perf_adjust_period() { if (period > 8*...) { stop() ... start() } } } start() } Which caused a double start and a double stop, thus triggering the assert in x86_pmu_start(). The patch fixes the problem by avoiding the double calls. We pass a new argument to perf_adjust_period() to indicate whether or not the event is already stopped. We can't just remove the start/stop from that function because it's called from __perf_event_overflow where the event needs to be reloaded via a stop/start back-toback call. The patch reintroduces the assertion in x86_pmu_start() which was removed by commit: 84f2b9b ("perf: Remove deprecated WARN_ON_ONCE()") In this second version, we've added calls to disable/enable PMU during unthrottling or frequency adjustment based on bug report of spurious NMI interrupts from Eric Dumazet. Reported-and-tested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Stephane Eranian <eranian@google.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: markus@trippelsdorf.de Cc: paulus@samba.org Link: http://lkml.kernel.org/r/20120207133956.GA4932@quad [ Minor edits to the changelog and to the code ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-02-07block: strip out locking optimization in put_io_context()Tejun Heo
put_io_context() performed a complex trylock dancing to avoid deferring ioc release to workqueue. It was also broken on UP because trylock was always assumed to succeed which resulted in unbalanced preemption count. While there are ways to fix the UP breakage, even the most pathological microbench (forced ioc allocation and tight fork/exit loop) fails to show any appreciable performance benefit of the optimization. Strip it out. If there turns out to be workloads which are affected by this change, simpler optimization from the discussion thread can be applied later. Signed-off-by: Tejun Heo <tj@kernel.org> LKML-Reference: <1328514611.21268.66.camel@sli10-conroe> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-02-04Merge tag 'pm-fixes-for-3.3-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Power management fixes for 3.3-rc3 Three power management regression fixes, one for a recent regression introcuded by the freezer changes during the 3.3 merge window and two for regressions in cpuidle (resulting from PM QoS changes) and in the hibernate user space interface, both introduced during the 3.2 development cycle. They include: * Two hibernate (s2disk) regression fixes from Srivatsa S. Bhat (for regressions introduced during the 3.3 merge window and during the 3.2 development cycle). * A cpuidle fix from Venki Pallipadi for a regression resulting from PM QoS changes during the 3.2 development cycle causing cpuidle to work incorrectly for CONFIG_PM unset. * tag 'pm-fixes-for-3.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: PM / QoS: CPU C-state breakage with PM Qos change PM / Freezer: Thaw only kernel threads if freezing of kernel threads fails PM / Hibernate: Thaw kernel threads in SNAPSHOT_CREATE_IMAGE ioctl path
2012-02-04PM / Freezer: Thaw only kernel threads if freezing of kernel threads failsSrivatsa S. Bhat
If freezing of kernel threads fails, we are expected to automatically thaw tasks in the error recovery path. However, at times, we encounter situations in which we would like the automatic error recovery path to thaw only the kernel threads, because we want to be able to do some more cleanup before we thaw userspace. Something like: error = freeze_kernel_threads(); if (error) { /* Do some cleanup */ /* Only then thaw userspace tasks*/ thaw_processes(); } An example of such a situation is where we freeze/thaw filesystems during suspend/hibernation. There, if freezing of kernel threads fails, we would like to thaw the frozen filesystems before thawing the userspace tasks. So, modify freeze_kernel_threads() to thaw only kernel threads in case of freezing failure. And change suspend_freeze_processes() accordingly. (At the same time, let us also get rid of the rather cryptic usage of the conditional operator (:?) in that function.) [rjw: In fact, this patch fixes a regression introduced during the 3.3 merge window, because without it thaw_processes() may be called before swsusp_free() in some situations and that may lead to massive memory allocation failures.] Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Nigel Cunningham <nigel@tuxonice.net> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-02-03kprobes: fix a memory leak in function pre_handler_kretprobe()Jiang Liu
In function pre_handler_kretprobe(), the allocated kretprobe_instance object will get leaked if the entry_handler callback returns non-zero. This may cause all the preallocated kretprobe_instance objects exhausted. This issue can be reproduced by changing samples/kprobes/kretprobe_example.c to probe "mutex_unlock". And the fix is straightforward: just put the allocated kretprobe_instance object back onto the free_instances list. [akpm@linux-foundation.org: use raw_spin_lock/unlock] Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Acked-by: Jim Keniston <jkenisto@us.ibm.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-02Fix race in process_vm_rw_coreChristopher Yeoh
This fixes the race in process_vm_core found by Oleg (see http://article.gmane.org/gmane.linux.kernel/1235667/ for details). This has been updated since I last sent it as the creation of the new mm_access() function did almost exactly the same thing as parts of the previous version of this patch did. In order to use mm_access() even when /proc isn't enabled, we move it to kernel/fork.c where other related process mm access functions already are. Signed-off-by: Chris Yeoh <yeohc@au1.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-02-02Merge branches 'core-urgent-for-linus', 'perf-urgent-for-linus', ↵Linus Torvalds
'sched-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: bugs, x86: Fix printk levels for panic, softlockups and stack dumps * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf top: Fix number of samples displayed perf tools: Fix strlen() bug in perf_event__synthesize_event_type() perf tools: Fix broken build by defining _GNU_SOURCE in Makefile x86/dumpstack: Remove unneeded check in dump_trace() perf: Fix broken interrupt rate throttling * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/rt: Fix task stack corruption under __ARCH_WANT_INTERRUPTS_ON_CTXSW sched: Fix ancient race in do_exit() sched/nohz: Fix nohz cpu idle load balancing state with cpu hotplug sched/s390: Fix compile error in sched/core.c sched: Fix rq->nr_uninterruptible update race * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/reboot: Remove VersaLogic Menlow reboot quirk x86/reboot: Skip DMI checks if reboot set by user x86: Properly parenthesize cmpxchg() macro arguments
2012-02-01PM / Hibernate: Thaw kernel threads in SNAPSHOT_CREATE_IMAGE ioctl pathSrivatsa S. Bhat
In the SNAPSHOT_CREATE_IMAGE ioctl, if the call to hibernation_snapshot() fails, the frozen tasks are not thawed. And in the case of success, if we happen to exit due to a successful freezer test, all tasks (including those of userspace) are thawed, whereas actually we should have thawed only the kernel threads at that point. Fix both these issues. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: stable@vger.kernel.org
2012-01-29PM / Hibernate: Fix s2disk regression related to freezing workqueuesRafael J. Wysocki
Commit 2aede851ddf08666f68ffc17be446420e9d2a056 PM / Hibernate: Freeze kernel threads after preallocating memory introduced a mechanism by which kernel threads were frozen after the preallocation of hibernate image memory to avoid problems with frozen kernel threads not responding to memory freeing requests. However, it overlooked the s2disk code path in which the SNAPSHOT_CREATE_IMAGE ioctl was run directly after SNAPSHOT_FREE, which caused freeze_workqueues_begin() to BUG(), because it saw that worqueues had been already frozen. Although in principle this issue might be addressed by removing the relevant BUG_ON() from freeze_workqueues_begin(), that would reintroduce the very problem that commit 2aede851ddf08666f68ffc17be4 attempted to avoid into that particular code path. For this reason, to fix the issue at hand, introduce thaw_kernel_threads() and make the SNAPSHOT_FREE ioctl execute it. Special thanks to Srivatsa S. Bhat for detailed analysis of the problem. Reported-and-tested-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: stable@kernel.org
2012-01-27sched/rt: Fix task stack corruption under __ARCH_WANT_INTERRUPTS_ON_CTXSWChanho Min
This issue happens under the following conditions: 1. preemption is off 2. __ARCH_WANT_INTERRUPTS_ON_CTXSW is defined 3. RT scheduling class 4. SMP system Sequence is as follows: 1.suppose current task is A. start schedule() 2.task A is enqueued pushable task at the entry of schedule() __schedule prev = rq->curr; ... put_prev_task put_prev_task_rt enqueue_pushable_task 4.pick the task B as next task. next = pick_next_task(rq); 3.rq->curr set to task B and context_switch is started. rq->curr = next; 4.At the entry of context_swtich, release this cpu's rq->lock. context_switch prepare_task_switch prepare_lock_switch raw_spin_unlock_irq(&rq->lock); 5.Shortly after rq->lock is released, interrupt is occurred and start IRQ context 6.try_to_wake_up() which called by ISR acquires rq->lock try_to_wake_up ttwu_remote rq = __task_rq_lock(p) ttwu_do_wakeup(rq, p, wake_flags); task_woken_rt 7.push_rt_task picks the task A which is enqueued before. task_woken_rt push_rt_tasks(rq) next_task = pick_next_pushable_task(rq) 8.At find_lock_lowest_rq(), If double_lock_balance() returns 0, lowest_rq can be the remote rq. (But,If preemption is on, double_lock_balance always return 1 and it does't happen.) push_rt_task find_lock_lowest_rq if (double_lock_balance(rq, lowest_rq)).. 9.find_lock_lowest_rq return the available rq. task A is migrated to the remote cpu/rq. push_rt_task ... deactivate_task(rq, next_task, 0); set_task_cpu(next_task, lowest_rq->cpu); activate_task(lowest_rq, next_task, 0); 10. But, task A is on irq context at this cpu. So, task A is scheduled by two cpus at the same time until restore from IRQ. Task A's stack is corrupted. To fix it, don't migrate an RT task if it's still running. Signed-off-by: Chanho Min <chanho.min@lge.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: <stable@kernel.org> Link: http://lkml.kernel.org/r/CAOAMb1BHA=5fm7KTewYyke6u-8DP0iUuJMpgQw54vNeXFsGpoQ@mail.gmail.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-27perf: Fix broken interrupt rate throttlingStephane Eranian
This patch fixes the sampling interrupt throttling mechanism. It was broken in v3.2. Events were not being unthrottled. The unthrottling mechanism required that events be checked at each timer tick. This patch solves this problem and also separates: - unthrottling - multiplexing - frequency-mode period adjustments Not all of them need to be executed at each timer tick. This third version of the patch is based on my original patch + PeterZ proposal (https://lkml.org/lkml/2012/1/7/87). At each timer tick, for each context: - if the current CPU has throttled events, we unthrottle events - if context has frequency-based events, we adjust sampling periods - if we have reached the jiffies interval, we multiplex (rotate) We decoupled rotation (multiplexing) from frequency-mode sampling period adjustments. They should not necessarily happen at the same rate. Multiplexing is subject to jiffies_interval (currently at 1 but could be higher once the tunable is exposed via sysfs). We have grouped frequency-mode adjustment and unthrottling into the same routine to minimize code duplication. When throttled while in frequency mode, we scan the events only once. We have fixed the threshold enforcement code in __perf_event_overflow(). There was a bug whereby it would allow more than the authorized rate because an increment of hwc->interrupts was not executed at the right place. The patch was tested with low sampling limit (2000) and fixed periods, frequency mode, overcommitted PMU. On a 2.1GHz AMD CPU: $ cat /proc/sys/kernel/perf_event_max_sample_rate 2000 We set a rate of 3000 samples/sec (2.1GHz/3000 = 700000): $ perf record -e cycles,cycles -c 700000 noploop 10 $ perf report -D | tail -21 Aggregated stats: TOTAL events: 80086 MMAP events: 88 COMM events: 2 EXIT events: 4 THROTTLE events: 19996 UNTHROTTLE events: 19996 SAMPLE events: 40000 cycles stats: TOTAL events: 40006 MMAP events: 5 COMM events: 1 EXIT events: 4 THROTTLE events: 9998 UNTHROTTLE events: 9998 SAMPLE events: 20000 cycles stats: TOTAL events: 39996 THROTTLE events: 9998 UNTHROTTLE events: 9998 SAMPLE events: 20000 For 10s, the cap is 2x2000x10 = 40000 samples. We get exactly that: 20000 samples/event. Signed-off-by: Stephane Eranian <eranian@google.com> Cc: <stable@kernel.org> # v3.2+ Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20120126160319.GA5655@quad Signed-off-by: Ingo Molnar <mingo@elte.hu>
2012-01-27sched: Fix ancient race in do_exit()Yasunori Goto
try_to_wake_up() has a problem which may change status from TASK_DEAD to TASK_RUNNING in race condition with SMI or guest environment of virtual machine. As a result, exited task is scheduled() again and panic occurs. Here is the sequence how it occurs: ----------------------------------+----------------------------- | CPU A | CPU B ----------------------------------+----------------------------- TASK A calls exit().... do_exit() exit_mm() down_read(mm->mmap_sem); rwsem_down_failed_common() set TASK_UNINTERRUPTIBLE set waiter.task <= task A list_add to sem->wait_list : raw_spin_unlock_irq() (I/O interruption occured) __rwsem_do_wake(mmap_sem) list_del(&waiter->list); waiter->task = NULL wake_up_process(task A) try_to_wake_up() (task is still TASK_UNINTERRUPTIBLE) p->on_rq is still 1.) ttwu_do_wakeup() (*A) : (I/O interruption handler finished) if (!waiter.task) schedule() is not called due to waiter.task is NULL. tsk->state = TASK_RUNNING : check_preempt_curr(); : task->state = TASK_DEAD (*B) <--- set TASK_RUNNING (*C) schedule() (exit task is running again) BUG_ON() is called! -------------------------------------------------------- The execution time between (*A) and (*B) is usually very short, because the interruption is disabled, and setting TASK_RUNNING at (*C) must be executed before setting TASK_DEAD. HOWEVER, if SMI is interrupted between (*A) and (*B), (*C) is able to execute AFTER setting TASK_DEAD! Then, exited task is scheduled again, and BUG_ON() is called.... If the system works on guest system of virtual machine, the time between (*A) and (*B) may be also long due to scheduling of hypervisor, and same phenomenon can occur. By this patch, do_exit() waits for releasing task->pi_lock which is used in try_to_wake_up(). It guarantees the task becomes TASK_DEAD after waking up. Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20120117174031.3118.E1E9C6FF@jp.fujitsu.com Signed-off-by: Ingo Molnar <mingo@elte.hu>