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2013-06-08Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: - Trivial: unused variable removal - Posix-timers: Add the clock ID to the new proc interface to make it useful. The interface is new and should be functional when we reach the final 3.10 release. - Cure a false positive warning in the tick code introduced by the overhaul in 3.10 - Fix for a persistent clock detection regression introduced in this cycle * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timekeeping: Correct run-time detection of persistent_clock. ntp: Remove unused variable flags in __hardpps posix-timers: Show clock ID in proc file tick: Cure broadcast false positive pending bit warning
2013-06-08Merge tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linuxLinus Torvalds
Pull irqdomain bug fixes from Grant Likely: "This branch contains a set of straight forward bug fixes to the irqdomain code and to a couple of drivers that make use of it." * tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux: irqchip: Return -EPERM for reserved IRQs irqdomain: document the simple domain first_irq kernel/irq/irqdomain.c: before use 'irq_data', need check it whether valid. irqdomain: export irq_domain_add_simple
2013-06-08irqdomain: document the simple domain first_irqLinus Walleij
The first_irq needs to be zero to get a linear domain and that comes with special semantics. We want to simplify this going forward but some documentation never hurts. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Grant Likely <grant.likely@linaro.org>
2013-06-08kernel/irq/irqdomain.c: before use 'irq_data', need check it whether valid.Chen Gang
Since irq_data may be NULL, if so, we WARN_ON(), and continue, 'hwirq' which related with 'irq_data' has to initialize later, or it will cause issue. Signed-off-by: Chen Gang <gang.chen@asianux.com> Signed-off-by: Grant Likely <grant.likely@linaro.org>
2013-06-08irqdomain: export irq_domain_add_simpleArnd Bergmann
All other irq_domain_add_* functions are exported already, and apparently this one got left out by mistake, which causes build errors for ARM allmodconfig kernels: ERROR: "irq_domain_add_simple" [drivers/gpio/gpio-rcar.ko] undefined! ERROR: "irq_domain_add_simple" [drivers/gpio/gpio-em.ko] undefined! Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Grant Likely <grant.likely@linaro.org>
2013-06-07Merge tag 'trace-fixes-v3.10-rc3-v3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "This contains 4 fixes. The first two fix the case where full RCU debugging is enabled, enabling function tracing causes a live lock of the system. This is due to the added debug checks in rcu_dereference_raw() that is used by the function tracer. These checks are also traced by the function tracer as well as cause enough overhead to the function tracer to slow down the system enough that the time to finish an interrupt can take longer than when the next interrupt is triggered, causing a live lock from the timer interrupt. Talking this over with Paul McKenney, we came up with a fix that adds a new rcu_dereference_raw_notrace() that does not perform these added checks, and let the function tracer use that. The third commit fixes a failed compile when branch tracing is enabled, due to the conversion of the trace_test_buffer() selftest that the branch trace wasn't converted for. The forth patch fixes a bug caught by the RCU lockdep code where a rcu_read_lock() is performed when rcu is disabled (either going to or from idle, or user space). This happened on the irqsoff tracer as it calls task_uid(). The fix here was to use current_uid() when possible that doesn't use rcu locking. Which luckily, is always used when irqsoff calls this code." * tag 'trace-fixes-v3.10-rc3-v3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Use current_uid() for critical time tracing tracing: Fix bad parameter passed in branch selftest ftrace: Use the rcu _notrace variants for rcu_dereference_raw() and friends rcu: Add _notrace variation of rcu_dereference_raw() and hlist_for_each_entry_rcu()
2013-06-06tracing: Use current_uid() for critical time tracingSteven Rostedt (Red Hat)
The irqsoff tracer records the max time that interrupts are disabled. There are hooks in the assembly code that calls back into the tracer when interrupts are disabled or enabled. When they are enabled, the tracer checks if the amount of time they were disabled is larger than the previous recorded max interrupts off time. If it is, it creates a snapshot of the currently running trace to store where the last largest interrupts off time was held and how it happened. During testing, this RCU lockdep dump appeared: [ 1257.829021] =============================== [ 1257.829021] [ INFO: suspicious RCU usage. ] [ 1257.829021] 3.10.0-rc1-test+ #171 Tainted: G W [ 1257.829021] ------------------------------- [ 1257.829021] /home/rostedt/work/git/linux-trace.git/include/linux/rcupdate.h:780 rcu_read_lock() used illegally while idle! [ 1257.829021] [ 1257.829021] other info that might help us debug this: [ 1257.829021] [ 1257.829021] [ 1257.829021] RCU used illegally from idle CPU! [ 1257.829021] rcu_scheduler_active = 1, debug_locks = 0 [ 1257.829021] RCU used illegally from extended quiescent state! [ 1257.829021] 2 locks held by trace-cmd/4831: [ 1257.829021] #0: (max_trace_lock){......}, at: [<ffffffff810e2b77>] stop_critical_timing+0x1a3/0x209 [ 1257.829021] #1: (rcu_read_lock){.+.+..}, at: [<ffffffff810dae5a>] __update_max_tr+0x88/0x1ee [ 1257.829021] [ 1257.829021] stack backtrace: [ 1257.829021] CPU: 3 PID: 4831 Comm: trace-cmd Tainted: G W 3.10.0-rc1-test+ #171 [ 1257.829021] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./To be filled by O.E.M., BIOS SDBLI944.86P 05/08/2007 [ 1257.829021] 0000000000000001 ffff880065f49da8 ffffffff8153dd2b ffff880065f49dd8 [ 1257.829021] ffffffff81092a00 ffff88006bd78680 ffff88007add7500 0000000000000003 [ 1257.829021] ffff88006bd78680 ffff880065f49e18 ffffffff810daebf ffffffff810dae5a [ 1257.829021] Call Trace: [ 1257.829021] [<ffffffff8153dd2b>] dump_stack+0x19/0x1b [ 1257.829021] [<ffffffff81092a00>] lockdep_rcu_suspicious+0x109/0x112 [ 1257.829021] [<ffffffff810daebf>] __update_max_tr+0xed/0x1ee [ 1257.829021] [<ffffffff810dae5a>] ? __update_max_tr+0x88/0x1ee [ 1257.829021] [<ffffffff811002b9>] ? user_enter+0xfd/0x107 [ 1257.829021] [<ffffffff810dbf85>] update_max_tr_single+0x11d/0x12d [ 1257.829021] [<ffffffff811002b9>] ? user_enter+0xfd/0x107 [ 1257.829021] [<ffffffff810e2b15>] stop_critical_timing+0x141/0x209 [ 1257.829021] [<ffffffff8109569a>] ? trace_hardirqs_on+0xd/0xf [ 1257.829021] [<ffffffff811002b9>] ? user_enter+0xfd/0x107 [ 1257.829021] [<ffffffff810e3057>] time_hardirqs_on+0x2a/0x2f [ 1257.829021] [<ffffffff811002b9>] ? user_enter+0xfd/0x107 [ 1257.829021] [<ffffffff8109550c>] trace_hardirqs_on_caller+0x16/0x197 [ 1257.829021] [<ffffffff8109569a>] trace_hardirqs_on+0xd/0xf [ 1257.829021] [<ffffffff811002b9>] user_enter+0xfd/0x107 [ 1257.829021] [<ffffffff810029b4>] do_notify_resume+0x92/0x97 [ 1257.829021] [<ffffffff8154bdca>] int_signal+0x12/0x17 What happened was entering into the user code, the interrupts were enabled and a max interrupts off was recorded. The trace buffer was saved along with various information about the task: comm, pid, uid, priority, etc. The uid is recorded with task_uid(tsk). But this is a macro that uses rcu_read_lock() to retrieve the data, and this happened to happen where RCU is blind (user_enter). As only the preempt and irqs off tracers can have this happen, and they both only have the tsk == current, if tsk == current, use current_uid() instead of task_uid(), as current_uid() does not use RCU as only current can change its uid. This fixes the RCU suspicious splat. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-06-03Merge branch 'for-3.10-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fixes from Tejun Heo: - Fix for yet another xattr bug which may lead to NULL deref. - A subtle bug in for_each_descendant_pre(). This bug requires quite specific conditions to trigger and isn't too likely to actually happen in the wild, but maybe that just makes it that much more nastier. - A warning message added for silly cgroup re-mount (not -o remount, but unmount followed by mount) behavior. * 'for-3.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: warn about mismatching options of a new mount of an existing hierarchy cgroup: fix a subtle bug in descendant pre-order walk cgroup: initialize xattr before calling d_instantiate()
2013-05-31Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Peter Anvin: - Three EFI-related fixes - Two early memory initialization fixes - build fix for older binutils - fix for an eager FPU performance regression -- currently we don't allow the use of the FPU at interrupt time *at all* in eager mode, which is clearly wrong. * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Allow FPU to be used at interrupt time even with eagerfpu x86, crc32-pclmul: Fix build with older binutils x86-64, init: Fix a possible wraparound bug in switchover in head_64.S x86, range: fix missing merge during add range x86, efi: initial the local variable of DataSize to zero efivar: fix oops in efivar_update_sysfs_entries() caused by memory reuse efivarfs: Never return ENOENT from firmware again
2013-05-29tracing: Fix bad parameter passed in branch selftestSteven Rostedt (Red Hat)
The branch selftest calls trace_test_buffer(), but with the new code it expects the first parameter to be a pointer to a struct trace_buffer. All self tests were changed but the branch selftest was missed. This caused either a crash or failed test when the branch selftest was enabled. Link: http://lkml.kernel.org/r/20130529141333.GA24064@localhost Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-29Merge branch 'fortglx/3.10/time' of ↵Thomas Gleixner
git://git.linaro.org/people/jstultz/linux into timers/urgent
2013-05-28ftrace: Use the rcu _notrace variants for rcu_dereference_raw() and friendsSteven Rostedt
As rcu_dereference_raw() under RCU debug config options can add quite a bit of checks, and that tracing uses rcu_dereference_raw(), these checks happen with the function tracer. The function tracer also happens to trace these debug checks too. This added overhead can livelock the system. Have the function tracer use the new RCU _notrace equivalents that do not do the debug checks for RCU. Link: http://lkml.kernel.org/r/20130528184209.467603904@goodmis.org Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-29cgroup: warn about mismatching options of a new mount of an existing hierarchyJeff Liu
With the new __DEVEL__sane_behavior mount option was introduced, if the root cgroup is alive with no xattr function, to mount a new cgroup with xattr will be rejected in terms of design which just fine. However, if the root cgroup does not mounted with __DEVEL__sane_hehavior, to create a new cgroup with xattr option will succeed although after that the EA function does not works as expected but will get ENOTSUPP for setting up attributes under either cgroup. e.g. setfattr: /cgroup2/test: Operation not supported Instead of keeping silence in this case, it's better to drop a log entry in warning level. That would be helpful to understand the reason behind the scene from the user's perspective, and this is essentially an improvement does not break the backward compatibilities. With this fix, above mount attemption will keep up works as usual but the following line cound be found at the system log: [ ...] cgroup: new mount options do not match the existing superblock tj: minor formatting / message updates. Signed-off-by: Jie Liu <jeff.liu@oracle.com> Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com> Signed-off-by: Tejun Heo <tj@kernel.org> Cc: stable@vger.kernel.org
2013-05-28timekeeping: Correct run-time detection of persistent_clock.Zoran Markovic
Since commit 31ade30692dc9680bfc95700d794818fa3f754ac, timekeeping_init() checks for presence of persistent clock by attempting to read a non-zero time value. This is an issue on platforms where persistent_clock (instead is implemented as a free-running counter (instead of an RTC) starting from zero on each boot and running during suspend. Examples are some ARM platforms (e.g. PandaBoard). An attempt to read such a clock during timekeeping_init() may return zero value and falsely declare persistent clock as missing. Additionally, in the above case suspend times may be accounted twice (once from timekeeping_resume() and once from rtc_resume()), resulting in a gradual drift of system time. This patch does a run-time correction of the issue by doing the same check during timekeeping_suspend(). A better long-term solution would have to return error when trying to read non-existing clock and zero when trying to read an uninitialized clock, but that would require changing all persistent_clock implementations. This patch addresses the immediate breakage, for now. Cc: John Stultz <john.stultz@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Feng Tang <feng.tang@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Zoran Markovic <zoran.markovic@linaro.org> [jstultz: Tweaked commit message and subject] Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-05-28ntp: Remove unused variable flags in __hardppsGeert Uytterhoeven
kernel/time/ntp.c: In function ‘__hardpps’: kernel/time/ntp.c:877: warning: unused variable ‘flags’ commit a076b2146fabb0894cae5e0189a8ba3f1502d737 ("ntp: Remove ntp_lock, using the timekeeping locks to protect ntp state") removed its users, but not the actual variable. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-05-28Merge tag 'trace-fixes-v3.10-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Two more fixes: The first one was reported by Mauro Carvalho Chehab, where if a poll() is done against a trace buffer for a CPU that has never been online, it will crash the kernel, as buffers are only created when a CPU comes on line, but the trace files are for all possible CPUs. This fix is to check if the buffer was allocated and if not return -EINVAL. That was the simple fix, the real fix is a bit more complex and not for a -rc release. We could have the files created when the CPUs come online. That would require some design changes. The second one was reported by Peter Zijlstra. If the kernel command line has ftrace=nop, it will lock up the system on boot up. This is because the new design for 3.10 has the nop tracer bootstrap the tracing subsystem. When ftrace=<trace> is defined, when a that tracer is registered, it starts the tracing, but uses the nop tracer to clear things out. What happened here was that ftrace=nop caused the registering of nop to start it and use nop before it was initialized. The only thing nop needs to have done to initialize it is to have the tracer point its current_tracer structure member to the nop tracer. Doing that before registering the nop tracer makes everything work." * tag 'trace-fixes-v3.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ring-buffer: Do not poll non allocated cpu buffers tracing: Fix crash when ftrace=nop on the kernel command line
2013-05-28ring-buffer: Do not poll non allocated cpu buffersSteven Rostedt (Red Hat)
The tracing infrastructure sets up for possible CPUs, but it uses the ring buffer polling, it is possible to call the ring buffer polling code with a CPU that hasn't been allocated. This will cause a kernel oops when it access a ring buffer cpu buffer that is part of the possible cpus but hasn't been allocated yet as the CPU has never been online. Reported-by: Mauro Carvalho Chehab <mchehab@redhat.com> Tested-by: Mauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-28tick: Cure broadcast false positive pending bit warningThomas Gleixner
commit 26517f3e (tick: Avoid programming the local cpu timer if broadcast pending) added a warning if the cpu enters broadcast mode again while the pending bit is still set. Meelis reported that the warning triggers. There are two corner cases which have been not considered: 1) cpuidle calls clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER) twice. That can result in the following scenario CPU0 CPU1 cpuidle_idle_call() clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER) set cpu in tick_broadcast_oneshot_mask broadcast interrupt event expired for cpu1 set pending bit acpi_idle_enter_simple() clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER) WARN_ON(pending bit) Move the WARN_ON into the section where we enter broadcast mode so it wont provide false positives on the second call. 2) safe_halt() enables interrupts, so a broadcast interrupt can be delivered befor the broadcast mode is disabled. That sets the pending bit for the CPU which receives the broadcast interrupt. Though the interrupt is delivered right away from the broadcast handler and leaves the pending bit stale. Clear the pending bit for the current cpu in the broadcast handler. Reported-and-tested-by: Meelis Roos <mroos@linux.ee> Cc: Len Brown <lenb@kernel.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Rafael J. Wysocki <rjw@sisk.pl> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1305271841130.4220@ionos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-05-24auditfilter.c: fix kernel-doc warningsRandy Dunlap
Fix kernel-doc warnings in kernel/auditfilter.c: Warning(kernel/auditfilter.c:1029): Excess function parameter 'loginuid' description in 'audit_receive_filter' Warning(kernel/auditfilter.c:1029): Excess function parameter 'sessionid' description in 'audit_receive_filter' Warning(kernel/auditfilter.c:1029): Excess function parameter 'sid' description in 'audit_receive_filter' Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Eric Paris <eparis@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-24Merge tag 'trace-fixes-v3.10-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fix from Steven Rostedt: "Masami Hiramatsu fixed another bug. This time returning a proper result in event_enable_func(). After checking the return status of try_module_get(), it returned the status of try_module_get(). But try_module_get() returns 0 on failure, which is success for event_enable_func()" * tag 'trace-fixes-v3.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Return -EBUSY when event_enable_func() fails to get module
2013-05-24cgroup: fix a subtle bug in descendant pre-order walkTejun Heo
When cgroup_next_descendant_pre() initiates a walk, it checks whether the subtree root doesn't have any children and if not returns NULL. Later code assumes that the subtree isn't empty. This is broken because the subtree may become empty inbetween, which can lead to the traversal escaping the subtree by walking to the sibling of the subtree root. There's no reason to have the early exit path. Remove it along with the later assumption that the subtree isn't empty. This simplifies the code a bit and fixes the subtle bug. While at it, fix the comment of cgroup_for_each_descendant_pre() which was incorrectly referring to ->css_offline() instead of ->css_online(). Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: stable@vger.kernel.org
2013-05-23tracing: Fix crash when ftrace=nop on the kernel command lineSteven Rostedt (Red Hat)
If ftrace=<tracer> is on the kernel command line, when that tracer is registered, it will be initiated by tracing_set_tracer() to execute that tracer. The nop tracer is just a stub tracer that is used to have no tracer enabled. It is assigned at early bootup as it is the default tracer. But if ftrace=nop is on the kernel command line, the registering of the nop tracer will call tracing_set_tracer() which will try to execute the nop tracer. But it expects tr->current_trace to be assigned something as it usually is assigned to the nop tracer. As it hasn't been assigned to anything yet, it causes the system to crash. The simple fix is to move the tr->current_trace = nop before registering the nop tracer. The functionality is still the same as the nop tracer doesn't do anything anyway. Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-18Merge tag 'kmemleak-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64 Pull kmemleak patches from Catalin Marinas: "Kmemleak now scans all the writable and non-executable module sections to avoid false positives (previously it was only scanning specific sections and missing .ref.data)." * tag 'kmemleak-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64: kmemleak: No need for scanning specific module sections kmemleak: Scan all allocated, writeable and not executable module sections
2013-05-17x86, range: fix missing merge during add rangeYinghai Lu
Christian found v3.9 does not work with E350 with EFI is enabled. [ 1.658832] Trying to unpack rootfs image as initramfs... [ 1.679935] BUG: unable to handle kernel paging request at ffff88006e3fd000 [ 1.686940] IP: [<ffffffff813661df>] memset+0x1f/0xb0 [ 1.692010] PGD 1f77067 PUD 1f7a067 PMD 61420067 PTE 0 but early memtest report all memory could be accessed without problem. early page table is set in following sequence: [ 0.000000] init_memory_mapping: [mem 0x00000000-0x000fffff] [ 0.000000] init_memory_mapping: [mem 0x6e600000-0x6e7fffff] [ 0.000000] init_memory_mapping: [mem 0x6c000000-0x6e5fffff] [ 0.000000] init_memory_mapping: [mem 0x00100000-0x6bffffff] [ 0.000000] init_memory_mapping: [mem 0x6e800000-0x6ea07fff] but later efi_enter_virtual_mode try set mapping again wrongly. [ 0.010644] pid_max: default: 32768 minimum: 301 [ 0.015302] init_memory_mapping: [mem 0x640c5000-0x6e3fcfff] that means it fails with pfn_range_is_mapped. It turns out that we have a bug in add_range_with_merge and it does not merge range properly when new add one fill the hole between two exsiting ranges. In the case when [mem 0x00100000-0x6bffffff] is the hole between [mem 0x00000000-0x000fffff] and [mem 0x6c000000-0x6e7fffff]. Fix the add_range_with_merge by calling itself recursively. Reported-by: "Christian König" <christian.koenig@amd.com> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/CAE9FiQVofGoSk7q5-0irjkBxemqK729cND4hov-1QCBJDhxpgQ@mail.gmail.com Cc: <stable@vger.kernel.org> v3.9 Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-05-17kmemleak: No need for scanning specific module sectionsSteven Rostedt
As kmemleak now scans all module sections that are allocated, writable and non executable, there's no need to scan individual sections that might reference data. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au>
2013-05-17kmemleak: Scan all allocated, writeable and not executable module sectionsSteven Rostedt
Instead of just picking data sections by name (names that start with .data, .bss or .ref.data), use the section flags and scan all sections that are allocated, writable and not executable. Which should cover all sections of a module that might reference data. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> [catalin.marinas@arm.com: removed unused 'name' variable] [catalin.marinas@arm.com: collapsed 'if' blocks] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au>
2013-05-16Merge branch 'for-3.10-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq Pull workqueue fixes from Tejun Heo: "Three more workqueue regression fixes. - Fix unbalanced unlock in trylock failure path of manage_workers(). This shouldn't happen often in the wild but is possible. - While making schedule_work() and friends inline, they become unavailable to !GPL modules. Allow !GPL modules to access basic stuff - system_wq and queue_*work_on() - so that schedule_work() and friends can be used. - During boot, the unbound NUMA support code allocates a cpumask for each possible node using alloc_cpumask_var_node(), which ends up trying to allocate node-specific memory even for offline nodes triggering BUG in the memory alloc code. Use NUMA_NO_NODE for offline nodes." * 'for-3.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: don't perform NUMA-aware allocations on offline nodes in wq_numa_init() workqueue: Make schedule_work() available again to non GPL modules workqueue: correct handling of the pool spin_lock
2013-05-16Merge branch 'rcu/urgent' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu Pull RCU fixes from Paul McKenney: "A couple of fixes for RCU regressions: - A boneheaded boolean-logic bug that resulted in excessive delays on boot, hibernation and suspend that was reported by Borislav Petkov, Bjørn Mork, and Joerg Roedel. The fix inserts a single "!". - A fix for a boot-time splat due to allocating from bootmem too late in boot, fix courtesy of Sasha Levin with additional help from Yinghai Lu." * 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: rcu: Don't allocate bootmem from rcu_init() rcu: Fix comparison sense in rcu_needs_cpu()
2013-05-16usermodehelper: check subprocess_info->path != NULLOleg Nesterov
argv_split(empty_or_all_spaces) happily succeeds, it simply returns argc == 0 and argv[0] == NULL. Change call_usermodehelper_exec() to check sub_info->path != NULL to avoid the crash. This is the minimal fix, todo: - perhaps we should change argv_split() to return NULL or change the callers. - kill or justify ->path[0] check - narrow the scope of helper_lock() Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-By: Lucas De Marchi <lucas.demarchi@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-16tracing: Return -EBUSY when event_enable_func() fails to get moduleMasami Hiramatsu
Since try_module_get() returns false( = 0) when it fails to pindown a module, event_enable_func() returns 0 which means "succeed". This can cause a kernel panic when the entry is removed, because the event is already released. This fixes the bug by returning -EBUSY, because the reason why it fails is that the module is being removed at that time. Link: http://lkml.kernel.org/r/20130516114848.13508.97899.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-15workqueue: don't perform NUMA-aware allocations on offline nodes in ↵Tejun Heo
wq_numa_init() wq_numa_init() builds per-node cpumasks which are later used to make unbound workqueues NUMA-aware. The cpumasks are allocated using alloc_cpumask_var_node() for all possible nodes. Unfortunately, on machines with off-line nodes, this leads to NUMA-aware allocations on existing bug offline nodes, which in turn triggers BUG in the memory allocation code. Fix it by using NUMA_NO_NODE for cpumask allocations for offline nodes. kernel BUG at include/linux/gfp.h:323! invalid opcode: 0000 [#1] SMP Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0+ #1 Hardware name: ProLiant BL465c G7, BIOS A19 12/10/2011 task: ffff880234608000 ti: ffff880234602000 task.ti: ffff880234602000 RIP: 0010:[<ffffffff8117495d>] [<ffffffff8117495d>] new_slab+0x2ad/0x340 RSP: 0000:ffff880234603bf8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff880237404b40 RCX: 00000000000000d0 RDX: 0000000000000001 RSI: 0000000000000003 RDI: 00000000002052d0 RBP: ffff880234603c28 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000001 R11: ffffffff812e3aa8 R12: 0000000000000001 R13: ffff8802378161c0 R14: 0000000000030027 R15: 00000000000040d0 FS: 0000000000000000(0000) GS:ffff880237800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: ffff88043fdff000 CR3: 00000000018d5000 CR4: 00000000000007f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: ffff880234603c28 0000000000000001 00000000000000d0 ffff8802378161c0 ffff880237404b40 ffff880237404b40 ffff880234603d28 ffffffff815edba1 ffff880237816140 0000000000000000 ffff88023740e1c0 Call Trace: [<ffffffff815edba1>] __slab_alloc+0x330/0x4f2 [<ffffffff81174b25>] kmem_cache_alloc_node_trace+0xa5/0x200 [<ffffffff812e3aa8>] alloc_cpumask_var_node+0x28/0x90 [<ffffffff81a0bdb3>] wq_numa_init+0x10d/0x1be [<ffffffff81a0bec8>] init_workqueues+0x64/0x341 [<ffffffff810002ea>] do_one_initcall+0xea/0x1a0 [<ffffffff819f1f31>] kernel_init_freeable+0xb7/0x1ec [<ffffffff815d50de>] kernel_init+0xe/0xf0 [<ffffffff815ff89c>] ret_from_fork+0x7c/0xb0 Code: 45 84 ac 00 00 00 f0 41 80 4d 00 40 e9 f6 fe ff ff 66 0f 1f 84 00 00 00 00 00 e8 eb 4b ff ff 49 89 c5 e9 05 fe ff ff <0f> 0b 4c 8b 73 38 44 89 ff 81 cf 00 00 20 00 4c 89 f6 48 c1 ee Signed-off-by: Tejun Heo <tj@kernel.org> Reported-and-Tested-by: Lingzhu Xiang <lxiang@redhat.com>
2013-05-15Merge tag 'trace-fixes-v3.10-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "This includes a fix to a memory leak when adding filters to traces. Also, Masami Hiramatsu fixed up some minor bugs that were discovered by sparse." * tag 'trace-fixes-v3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/kprobes: Make print_*probe_event static tracing/kprobes: Fix a sparse warning for incorrect type in assignment tracing/kprobes: Use rcu_dereference_raw for tp->files tracing: Fix leaks of filter preds
2013-05-15Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: - Fix for a task exit cleanup race caused by a missing a preempt disable - Cleanup of the event notification functions with a massive reduction of duplicated code * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf: Factor out auxiliary events notification perf: Fix EXIT event notification
2013-05-15Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: - Cure for not using zalloc in the first place, which leads to random crashes with CPUMASK_OFF_STACK. - Revert a user space visible change which broke udev - Add a missing cpu_online early return introduced by the new full dyntick conversions - Plug a long standing race in the timer wheel cpu hotplug code. Sigh... - Cleanup NOHZ per cpu data on cpu down to prevent stale data on cpu up. * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: time: Revert ALWAYS_USE_PERSISTENT_CLOCK compile time optimizaitons timer: Don't reinitialize the cpu base lock during CPU_UP_PREPARE tick: Don't invoke tick_nohz_stop_sched_tick() if the cpu is offline tick: Cleanup NOHZ per cpu data on cpu down tick: Use zalloc_cpumask_var for allocating offstack cpumasks
2013-05-15Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core fixes from Thomas Gleixner: - Two fixlets for the fallout of the generic idle task conversion - Documentation update * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rcu/idle: Wrap cpu-idle poll mode within rcu_idle_enter/exit idle: Fix hlt/nohlt command-line handling in new generic idle kthread: Document ways of reducing OS jitter due to per-CPU kthreads
2013-05-15tracing/kprobes: Make print_*probe_event staticMasami Hiramatsu
According to sparse warning, print_*probe_event static because those functions are not directly called from outside. Link: http://lkml.kernel.org/r/20130513115839.6545.83067.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-15tracing/kprobes: Fix a sparse warning for incorrect type in assignmentMasami Hiramatsu
Fix a sparse warning about the rcu operated pointer is defined without __rcu address space. Link: http://lkml.kernel.org/r/20130513115837.6545.23322.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-15tracing/kprobes: Use rcu_dereference_raw for tp->filesMasami Hiramatsu
Use rcu_dereference_raw() for accessing tp->files. Because the write-side uses rcu_assign_pointer() for memory barrier, the read-side also has to use rcu_dereference_raw() with read memory barrier. Link: http://lkml.kernel.org/r/20130513115834.6545.17022.stgit@mhiramat-M0-7522 Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tom Zanussi <tom.zanussi@intel.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-15tracing: Fix leaks of filter predsSteven Rostedt (Red Hat)
Special preds are created when folding a series of preds that can be done in serial. These are allocated in an ops field of the pred structure. But they were never freed, causing memory leaks. This was discovered using the kmemleak checker: unreferenced object 0xffff8800797fd5e0 (size 32): comm "swapper/0", pid 1, jiffies 4294690605 (age 104.608s) hex dump (first 32 bytes): 00 00 01 00 03 00 05 00 07 00 09 00 0b 00 0d 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff814b52af>] kmemleak_alloc+0x73/0x98 [<ffffffff8111ff84>] kmemleak_alloc_recursive.constprop.42+0x16/0x18 [<ffffffff81120e68>] __kmalloc+0xd7/0x125 [<ffffffff810d47eb>] kcalloc.constprop.24+0x2d/0x2f [<ffffffff810d4896>] fold_pred_tree_cb+0xa9/0xf4 [<ffffffff810d3781>] walk_pred_tree+0x47/0xcc [<ffffffff810d5030>] replace_preds.isra.20+0x6f8/0x72f [<ffffffff810d50b5>] create_filter+0x4e/0x8b [<ffffffff81b1c30d>] ftrace_test_event_filter+0x5a/0x155 [<ffffffff8100028d>] do_one_initcall+0xa0/0x137 [<ffffffff81afbedf>] kernel_init_freeable+0x14d/0x1dc [<ffffffff814b24b7>] kernel_init+0xe/0xdb [<ffffffff814d539c>] ret_from_fork+0x7c/0xb0 [<ffffffffffffffff>] 0xffffffffffffffff Cc: Tom Zanussi <tzanussi@gmail.com> Cc: stable@vger.kernel.org # 2.6.39+ Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-05-15rcu: Don't allocate bootmem from rcu_init()Sasha Levin
When rcu_init() is called we already have slab working, allocating bootmem at that point results in warnings and an allocation from slab. This commit therefore changes alloc_bootmem_cpumask_var() to alloc_cpumask_var() in rcu_bootup_announce_oddness(), which is called from rcu_init(). Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Tested-by: Robin Holt <holt@sgi.com> [paulmck: convert to zalloc_cpumask_var(), as suggested by Yinghai Lu.]
2013-05-14time: Revert ALWAYS_USE_PERSISTENT_CLOCK compile time optimizaitonsJohn Stultz
Kay Sievers noted that the ALWAYS_USE_PERSISTENT_CLOCK config, which enables some minor compile time optimization to avoid uncessary code in mostly the suspend/resume path could cause problems for userland. In particular, the dependency for RTC_HCTOSYS on !ALWAYS_USE_PERSISTENT_CLOCK, which avoids setting the time twice and simplifies suspend/resume, has the side effect of causing the /sys/class/rtc/rtcN/hctosys flag to always be zero, and this flag is commonly used by udev to setup the /dev/rtc symlink to /dev/rtcN, which can cause pain for older applications. While the udev rules could use some work to be less fragile, breaking userland should strongly be avoided. Additionally the compile time optimizations are fairly minor, and the code being optimized is likely to be reworked in the future, so lets revert this change. Reported-by: Kay Sievers <kay@vrfy.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: stable <stable@vger.kernel.org> #3.9 Cc: Feng Tang <feng.tang@intel.com> Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Link: http://lkml.kernel.org/r/1366828376-18124-1-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-05-14workqueue: Make schedule_work() available again to non GPL modulesMarc Dionne
Commit 8425e3d5bdbe ("workqueue: inline trivial wrappers") changed schedule_work() and schedule_delayed_work() to inline wrappers, but these rely on some symbols that are EXPORT_SYMBOL_GPL, while the original functions were EXPORT_SYMBOL. This has the effect of changing the licensing requirement for these functions and making them unavailable to non GPL modules. Make them available again by removing the restriction on the required symbols. Signed-off-by: Marc Dionne <marc.dionne@your-file-system.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2013-05-14workqueue: correct handling of the pool spin_lockJoonsoo Kim
When we fail to mutex_trylock(), we release the pool spin_lock and do mutex_lock(). After that, we should regrab the pool spin_lock, but, regrabbing is missed in current code. So correct it. Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2013-05-14rcu: Fix comparison sense in rcu_needs_cpu()Paul E. McKenney
Commit c0f4dfd4f (rcu: Make RCU_FAST_NO_HZ take advantage of numbered callbacks) introduced a bug that can result in excessively long grace periods. This bug reverse the senes of the "if" statement checking for lazy callbacks, so that RCU takes a lazy approach when there are in fact non-lazy callbacks. This can result in excessive boot, suspend, and resume times. This commit therefore fixes the sense of this "if" statement. Reported-by: Borislav Petkov <bp@alien8.de> Reported-by: Bjørn Mork <bjorn@mork.no> Reported-by: Joerg Roedel <joro@8bytes.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Bjørn Mork <bjorn@mork.no> Tested-by: Joerg Roedel <joro@8bytes.org>
2013-05-14Merge branch 'for-3.10-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq Pull workqueue fix from Tejun Heo: "A fix for a workqueue_congested() regression that broke fscache" * 'for-3.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: workqueue_congested() shouldn't translate WORK_CPU_UNBOUND into node number
2013-05-14timer: Don't reinitialize the cpu base lock during CPU_UP_PREPARETirupathi Reddy
An inactive timer's base can refer to a offline cpu's base. In the current code, cpu_base's lock is blindly reinitialized each time a CPU is brought up. If a CPU is brought online during the period that another thread is trying to modify an inactive timer on that CPU with holding its timer base lock, then the lock will be reinitialized under its feet. This leads to following SPIN_BUG(). <0> BUG: spinlock already unlocked on CPU#3, kworker/u:3/1466 <0> lock: 0xe3ebe000, .magic: dead4ead, .owner: kworker/u:3/1466, .owner_cpu: 1 <4> [<c0013dc4>] (unwind_backtrace+0x0/0x11c) from [<c026e794>] (do_raw_spin_unlock+0x40/0xcc) <4> [<c026e794>] (do_raw_spin_unlock+0x40/0xcc) from [<c076c160>] (_raw_spin_unlock+0x8/0x30) <4> [<c076c160>] (_raw_spin_unlock+0x8/0x30) from [<c009b858>] (mod_timer+0x294/0x310) <4> [<c009b858>] (mod_timer+0x294/0x310) from [<c00a5e04>] (queue_delayed_work_on+0x104/0x120) <4> [<c00a5e04>] (queue_delayed_work_on+0x104/0x120) from [<c04eae00>] (sdhci_msm_bus_voting+0x88/0x9c) <4> [<c04eae00>] (sdhci_msm_bus_voting+0x88/0x9c) from [<c04d8780>] (sdhci_disable+0x40/0x48) <4> [<c04d8780>] (sdhci_disable+0x40/0x48) from [<c04bf300>] (mmc_release_host+0x4c/0xb0) <4> [<c04bf300>] (mmc_release_host+0x4c/0xb0) from [<c04c7aac>] (mmc_sd_detect+0x90/0xfc) <4> [<c04c7aac>] (mmc_sd_detect+0x90/0xfc) from [<c04c2504>] (mmc_rescan+0x7c/0x2c4) <4> [<c04c2504>] (mmc_rescan+0x7c/0x2c4) from [<c00a6a7c>] (process_one_work+0x27c/0x484) <4> [<c00a6a7c>] (process_one_work+0x27c/0x484) from [<c00a6e94>] (worker_thread+0x210/0x3b0) <4> [<c00a6e94>] (worker_thread+0x210/0x3b0) from [<c00aad9c>] (kthread+0x80/0x8c) <4> [<c00aad9c>] (kthread+0x80/0x8c) from [<c000ea80>] (kernel_thread_exit+0x0/0x8) As an example, this particular crash occurred when CPU #3 is executing mod_timer() on an inactive timer whose base is refered to offlined CPU #2. The code locked the timer_base corresponding to CPU #2. Before it could proceed, CPU #2 came online and reinitialized the spinlock corresponding to its base. Thus now CPU #3 held a lock which was reinitialized. When CPU #3 finally ended up unlocking the old cpu_base corresponding to CPU #2, we hit the above SPIN_BUG(). CPU #0 CPU #3 CPU #2 ------ ------- ------- ..... ...... <Offline> mod_timer() lock_timer_base spin_lock_irqsave(&base->lock) cpu_up(2) ..... ...... init_timers_cpu() .... ..... spin_lock_init(&base->lock) ..... spin_unlock_irqrestore(&base->lock) ...... <spin_bug> Allocation of per_cpu timer vector bases is done only once under "tvec_base_done[]" check. In the current code, spinlock_initialization of base->lock isn't under this check. When a CPU is up each time the base lock is reinitialized. Move base spinlock initialization under the check. Signed-off-by: Tirupathi Reddy <tirupath@codeaurora.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1368520142-4136-1-git-send-email-tirupath@codeaurora.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-05-14rcu/idle: Wrap cpu-idle poll mode within rcu_idle_enter/exitSrivatsa S. Bhat
Bjørn Mork reported the following warning when running powertop. [ 49.289034] ------------[ cut here ]------------ [ 49.289055] WARNING: at kernel/rcutree.c:502 rcu_eqs_exit_common.isra.48+0x3d/0x125() [ 49.289244] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.10.0-bisect-rcu-warn+ #107 [ 49.289251] ffffffff8157d8c8 ffffffff81801e28 ffffffff8137e4e3 ffffffff81801e68 [ 49.289260] ffffffff8103094f ffffffff81801e68 0000000000000000 ffff88023afcd9b0 [ 49.289268] 0000000000000000 0140000000000000 ffff88023bee7700 ffffffff81801e78 [ 49.289276] Call Trace: [ 49.289285] [<ffffffff8137e4e3>] dump_stack+0x19/0x1b [ 49.289293] [<ffffffff8103094f>] warn_slowpath_common+0x62/0x7b [ 49.289300] [<ffffffff8103097d>] warn_slowpath_null+0x15/0x17 [ 49.289306] [<ffffffff810a9006>] rcu_eqs_exit_common.isra.48+0x3d/0x125 [ 49.289314] [<ffffffff81079b49>] ? trace_hardirqs_off_caller+0x37/0xa6 [ 49.289320] [<ffffffff810a9692>] rcu_idle_exit+0x85/0xa8 [ 49.289327] [<ffffffff8107076e>] trace_cpu_idle_rcuidle+0xae/0xff [ 49.289334] [<ffffffff810708b1>] cpu_startup_entry+0x72/0x115 [ 49.289341] [<ffffffff813689e5>] rest_init+0x149/0x150 [ 49.289347] [<ffffffff8136889c>] ? csum_partial_copy_generic+0x16c/0x16c [ 49.289355] [<ffffffff81a82d34>] start_kernel+0x3f0/0x3fd [ 49.289362] [<ffffffff81a8274c>] ? repair_env_string+0x5a/0x5a [ 49.289368] [<ffffffff81a82481>] x86_64_start_reservations+0x2a/0x2c [ 49.289375] [<ffffffff81a82550>] x86_64_start_kernel+0xcd/0xd1 [ 49.289379] ---[ end trace 07a1cc95e29e9036 ]--- The warning is that 'rdtp->dynticks' has an unexpected value, which roughly translates to - the calls to rcu_idle_enter() and rcu_idle_exit() were not made in the correct order, or otherwise messed up. And Bjørn's painstaking debugging indicated that this happens when the idle loop enters the poll mode. Looking at the poll function cpu_idle_poll(), and the implementation of trace_cpu_idle_rcuidle(), the problem becomes very clear: cpu_idle_poll() lacks calls to rcu_idle_enter/exit(), and trace_cpu_idle_rcuidle() calls them in the reverse order - first rcu_idle_exit(), and then rcu_idle_enter(). Hence the even/odd alternative sequencing of rdtp->dynticks goes for a toss. And powertop readily triggers this because powertop uses the idle-tracing infrastructure extensively. So, to fix this, wrap the code in cpu_idle_poll() within rcu_idle_enter/exit(), so that it blends properly with the calls inside trace_cpu_idle_rcuidle() and thus get the function ordering right. Reported-and-tested-by: Bjørn Mork <bjorn@mork.no> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Dipankar Sarma <dipankar@in.ibm.com> Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/519169BF.4080208@linux.vnet.ibm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-05-14tick: Don't invoke tick_nohz_stop_sched_tick() if the cpu is offlineThomas Gleixner
commit 5b39939a4 (nohz: Move ts->idle_calls incrementation into strict idle logic) moved code out of tick_nohz_stop_sched_tick() and missed to bail out when the cpu is offline. That's causing subsequent failures as an offline CPU is supposed to die and not to fiddle with nohz magic. Return false in can_stop_idle_tick() if the cpu is offline. Reported-and-tested-by: Jiri Kosina <jkosina@suse.cz> Reported-and-tested-by: Prarit Bhargava <prarit@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Tony Luck <tony.luck@intel.com> Cc: x86@kernel.org Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1305132138160.2863@ionos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-05-14cgroup: initialize xattr before calling d_instantiate()Li Zefan
cgroup_create_file() calls d_instantiate(), which may decide to look at the xattrs on the file. Smack always does this and SELinux can be configured to do so. But cgroup_add_file() didn't initialize xattrs before calling cgroup_create_file(), which finally leads to dereferencing NULL dentry->d_fsdata. This bug has been there since cgroup xattr was introduced. Cc: <stable@vger.kernel.org> # 3.8.x Reported-by: Ivan Bulatovic <combuster@archlinux.us> Reported-by: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2013-05-12tick: Cleanup NOHZ per cpu data on cpu downThomas Gleixner
Prarit reported a crash on CPU offline/online. The reason is that on CPU down the NOHZ related per cpu data of the dead cpu is not cleaned up. If at cpu online an interrupt happens before the per cpu tick device is registered the irq_enter() check potentially sees stale data and dereferences a NULL pointer. Cleanup the data after the cpu is dead. Reported-by: Prarit Bhargava <prarit@redhat.com> Cc: stable@vger.kernel.org Cc: Mike Galbraith <bitbucket@online.de> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1305031451561.2886@ionos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>