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* workqueue: dump workqueues on sysrq-tTejun Heo2015-03-091-0/+160
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Workqueues are used extensively throughout the kernel but sometimes it's difficult to debug stalls involving work items because visibility into its inner workings is fairly limited. Although sysrq-t task dump annotates each active worker task with the information on the work item being executed, it is challenging to find out which work items are pending or delayed on which queues and how pools are being managed. This patch implements show_workqueue_state() which dumps all busy workqueues and pools and is called from the sysrq-t handler. At the end of sysrq-t dump, something like the following is printed. Showing busy workqueues and worker pools: ... workqueue filler_wq: flags=0x0 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=2/256 in-flight: 491:filler_workfn, 507:filler_workfn pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=2/256 in-flight: 501:filler_workfn pending: filler_workfn ... workqueue test_wq: flags=0x8 pwq 2: cpus=1 node=0 flags=0x0 nice=0 active=1/1 in-flight: 510(RESCUER):test_workfn BAR(69) BAR(500) delayed: test_workfn1 BAR(492), test_workfn2 ... pool 0: cpus=0 node=0 flags=0x0 nice=0 workers=2 manager: 137 pool 2: cpus=1 node=0 flags=0x0 nice=0 workers=3 manager: 469 pool 3: cpus=1 node=0 flags=0x0 nice=-20 workers=2 idle: 16 pool 8: cpus=0-3 flags=0x4 nice=0 workers=2 manager: 62 The above shows that test_wq is executing test_workfn() on pid 510 which is the rescuer and also that there are two tasks 69 and 500 waiting for the work item to finish in flush_work(). As test_wq has max_active of 1, there are two work items for test_workfn1() and test_workfn2() which are delayed till the current work item is finished. In addition, pid 492 is flushing test_workfn1(). The work item for test_workfn() is being executed on pwq of pool 2 which is the normal priority per-cpu pool for CPU 1. The pool has three workers, two of which are executing filler_workfn() for filler_wq and the last one is assuming the manager role trying to create more workers. This extra workqueue state dump will hopefully help chasing down hangs involving workqueues. v3: cpulist_pr_cont() replaced with "%*pbl" printf formatting. v2: As suggested by Andrew, minor formatting change in pr_cont_work(), printk()'s replaced with pr_info()'s, and cpumask printing now uses cpulist_pr_cont(). Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> CC: Ingo Molnar <mingo@redhat.com>
* workqueue: keep track of the flushing task and pool managerTejun Heo2015-03-091-0/+5
| | | | | | | | Add wq_barrier->task and worker_pool->manager to keep track of the flushing task and pool manager respectively. These are purely informational and will be used to implement sysrq dump of workqueues. Signed-off-by: Tejun Heo <tj@kernel.org>
* workqueue: make the workqueues list RCU walkableTejun Heo2015-03-091-16/+31
| | | | | | | | | | | | | | | | | | | The workqueues list is protected by wq_pool_mutex and a workqueue and its subordinate data structures are freed directly on destruction. We want to add the ability dump workqueues from a sysrq callback which requires walking all workqueues without grabbing wq_pool_mutex. This patch makes freeing of workqueues RCU protected and makes the workqueues list walkable while holding RCU read lock. Note that pool_workqueues and pools are already sched-RCU protected. For consistency, workqueues are also protected with sched-RCU. While at it, reverse the workqueues list so that a workqueue which is created earlier comes before. The order of the list isn't significant functionally but this makes the planned sysrq dump list system workqueues first. Signed-off-by: Tejun Heo <tj@kernel.org>
* workqueue: fix hang involving racing cancel[_delayed]_work_sync()'s for ↵Tejun Heo2015-03-051-4/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PREEMPT_NONE cancel[_delayed]_work_sync() are implemented using __cancel_work_timer() which grabs the PENDING bit using try_to_grab_pending() and then flushes the work item with PENDING set to prevent the on-going execution of the work item from requeueing itself. try_to_grab_pending() can always grab PENDING bit without blocking except when someone else is doing the above flushing during cancelation. In that case, try_to_grab_pending() returns -ENOENT. In this case, __cancel_work_timer() currently invokes flush_work(). The assumption is that the completion of the work item is what the other canceling task would be waiting for too and thus waiting for the same condition and retrying should allow forward progress without excessive busy looping Unfortunately, this doesn't work if preemption is disabled or the latter task has real time priority. Let's say task A just got woken up from flush_work() by the completion of the target work item. If, before task A starts executing, task B gets scheduled and invokes __cancel_work_timer() on the same work item, its try_to_grab_pending() will return -ENOENT as the work item is still being canceled by task A and flush_work() will also immediately return false as the work item is no longer executing. This puts task B in a busy loop possibly preventing task A from executing and clearing the canceling state on the work item leading to a hang. task A task B worker executing work __cancel_work_timer() try_to_grab_pending() set work CANCELING flush_work() block for work completion completion, wakes up A __cancel_work_timer() while (forever) { try_to_grab_pending() -ENOENT as work is being canceled flush_work() false as work is no longer executing } This patch removes the possible hang by updating __cancel_work_timer() to explicitly wait for clearing of CANCELING rather than invoking flush_work() after try_to_grab_pending() fails with -ENOENT. Link: http://lkml.kernel.org/g/20150206171156.GA8942@axis.com v3: bit_waitqueue() can't be used for work items defined in vmalloc area. Switched to custom wake function which matches the target work item and exclusive wait and wakeup. v2: v1 used wake_up() on bit_waitqueue() which leads to NULL deref if the target bit waitqueue has wait_bit_queue's on it. Use DEFINE_WAIT_BIT() and __wake_up_bit() instead. Reported by Tomeu Vizoso. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Rabin Vincent <rabin.vincent@axis.com> Cc: Tomeu Vizoso <tomeu.vizoso@gmail.com> Cc: stable@vger.kernel.org Tested-by: Jesper Nilsson <jesper.nilsson@axis.com> Tested-by: Rabin Vincent <rabin.vincent@axis.com>
* Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linusLinus Torvalds2015-02-221-0/+12
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull MIPS updates from Ralf Baechle: "This is the main pull request for MIPS: - a number of fixes that didn't make the 3.19 release. - a number of cleanups. - preliminary support for Cavium's Octeon 3 SOCs which feature up to 48 MIPS64 R3 cores with FPU and hardware virtualization. - support for MIPS R6 processors. Revision 6 of the MIPS architecture is a major revision of the MIPS architecture which does away with many of original sins of the architecture such as branch delay slots. This and other changes in R6 require major changes throughout the entire MIPS core architecture code and make up for the lion share of this pull request. - finally some preparatory work for eXtendend Physical Address support, which allows support of up to 40 bit of physical address space on 32 bit processors" [ Ahh, MIPS can't leave the PAE brain damage alone. It's like every CPU architect has to make that mistake, but pee in the snow by changing the TLA. But whether it's called PAE, LPAE or XPA, it's horrid crud - Linus ] * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (114 commits) MIPS: sead3: Corrected get_c0_perfcount_int MIPS: mm: Remove dead macro definitions MIPS: OCTEON: irq: add CIB and other fixes MIPS: OCTEON: Don't do acknowledge operations for level triggered irqs. MIPS: OCTEON: More OCTEONIII support MIPS: OCTEON: Remove setting of processor specific CVMCTL icache bits. MIPS: OCTEON: Core-15169 Workaround and general CVMSEG cleanup. MIPS: OCTEON: Update octeon-model.h code for new SoCs. MIPS: OCTEON: Implement DCache errata workaround for all CN6XXX MIPS: OCTEON: Add little-endian support to asm/octeon/octeon.h MIPS: OCTEON: Implement the core-16057 workaround MIPS: OCTEON: Delete unused COP2 saving code MIPS: OCTEON: Use correct instruction to read 64-bit COP0 register MIPS: OCTEON: Save and restore CP2 SHA3 state MIPS: OCTEON: Fix FP context save. MIPS: OCTEON: Save/Restore wider multiply registers in OCTEON III CPUs MIPS: boot: Provide more uImage options MIPS: Remove unneeded #ifdef __KERNEL__ from asm/processor.h MIPS: ip22-gio: Remove legacy suspend/resume support mips: pci: Add ifdef around pci_proc_domain ...
| * MIPS,prctl: add PR_[GS]ET_FP_MODE prctl options for MIPSPaul Burton2015-02-121-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Userland code may be built using an ABI which permits linking to objects that have more restrictive floating point requirements. For example, userland code may be built to target the O32 FPXX ABI. Such code may be linked with other FPXX code, or code built for either one of the more restrictive FP32 or FP64. When linking with more restrictive code, the overall requirement of the process becomes that of the more restrictive code. The kernel has no way to know in advance which mode the process will need to be executed in, and indeed it may need to change during execution. The dynamic loader is the only code which will know the overall required mode, and so it needs to have a means to instruct the kernel to switch the FP mode of the process. This patch introduces 2 new options to the prctl syscall which provide such a capability. The FP mode of the process is represented as a simple bitmask combining a number of mode bits mirroring those present in the hardware. Userland can either retrieve the current FP mode of the process: mode = prctl(PR_GET_FP_MODE); or modify the current FP mode of the process: err = prctl(PR_SET_FP_MODE, new_mode); Signed-off-by: Paul Burton <paul.burton@imgtec.com> Cc: Matthew Fortune <matthew.fortune@imgtec.com> Cc: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/8899/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* | Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2015-02-211-3/+7
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull ntp fix from Ingo Molnar: "An adjtimex interface regression fix for 32-bit systems" [ A check that was added in a previous commit is really only a concern for 64bit systems, but was applied to both 32 and 64bit systems, which results in breaking 32bit systems. Thus the fix here is to make the check only apply to 64bit systems ] * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: ntp: Fixup adjtimex freq validation on 32-bit systems
| * | ntp: Fixup adjtimex freq validation on 32-bit systemsJohn Stultz2015-02-181-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Additional validation of adjtimex freq values to avoid potential multiplication overflows were added in commit 5e5aeb4367b (time: adjtimex: Validate the ADJ_FREQUENCY values) Unfortunately the patch used LONG_MAX/MIN instead of LLONG_MAX/MIN, which was fine on 64-bit systems, but being much smaller on 32-bit systems caused false positives resulting in most direct frequency adjustments to fail w/ EINVAL. ntpd only does direct frequency adjustments at startup, so the issue was not as easily observed there, but other time sync applications like ptpd and chrony were more effected by the bug. See bugs: https://bugzilla.kernel.org/show_bug.cgi?id=92481 https://bugzilla.redhat.com/show_bug.cgi?id=1188074 This patch changes the checks to use LLONG_MAX for clarity, and additionally the checks are disabled on 32-bit systems since LLONG_MAX/PPM_SCALE is always larger then the 32-bit long freq value, so multiplication overflows aren't possible there. Reported-by: Josh Boyer <jwboyer@fedoraproject.org> Reported-by: George Joseph <george.joseph@fairview5.com> Tested-by: George Joseph <george.joseph@fairview5.com> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> # v3.19+ Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Sasha Levin <sasha.levin@oracle.com> Link: http://lkml.kernel.org/r/1423553436-29747-1-git-send-email-john.stultz@linaro.org [ Prettified the changelog and the comments a bit. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | Merge branch 'locking-urgent-for-linus' of ↵Linus Torvalds2015-02-211-1/+2
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Ingo Molnar: "Two fixes: the paravirt spin_unlock() corruption/crash fix, and an rtmutex NULL dereference crash fix" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/spinlocks/paravirt: Fix memory corruption on unlock locking/rtmutex: Avoid a NULL pointer dereference on deadlock
| * | | locking/rtmutex: Avoid a NULL pointer dereference on deadlockSebastian Andrzej Siewior2015-02-181-1/+2
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With task_blocks_on_rt_mutex() returning early -EDEADLK we never add the waiter to the waitqueue. Later, we try to remove it via remove_waiter() and go boom in rt_mutex_top_waiter() because rb_entry() gives a NULL pointer. ( Tested on v3.18-RT where rtmutex is used for regular mutex and I tried to get one twice in a row. ) Not sure when this started but I guess 397335f004f4 ("rtmutex: Fix deadlock detector for real") or commit 3d5c9340d194 ("rtmutex: Handle deadlock detection smarter"). Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> # for v3.16 and later kernels Link: http://lkml.kernel.org/r/1424187823-19600-1-git-send-email-bigeasy@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds2015-02-215-99/+148
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar: "Thiscontains misc fixes: preempt_schedule_common() and io_schedule() recursion fixes, sched/dl fixes, a completion_done() revert, two sched/rt fixes and a comment update patch" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/rt: Avoid obvious configuration fail sched/autogroup: Fix failure to set cpu.rt_runtime_us sched/dl: Do update_rq_clock() in yield_task_dl() sched: Prevent recursion in io_schedule() sched/completion: Serialize completion_done() with complete() sched: Fix preempt_schedule_common() triggering tracing recursion sched/dl: Prevent enqueue of a sleeping task in dl_task_timer() sched: Make dl_task_time() use task_rq_lock() sched: Clarify ordering between task_rq_lock() and move_queued_task()
| * | | sched/rt: Avoid obvious configuration failPeter Zijlstra2015-02-181-3/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Setting the root group's cpu.rt_runtime_us to 0 is a bad thing; it would disallow the kernel creating RT tasks. One can of course still set it to 1, which will (likely) still wreck your kernel, but at least make it clear that setting it to 0 is not good. Collect both sanity checks into the one place while we're there. Suggested-by: Zefan Li <lizefan@huawei.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20150209112715.GO24151@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | sched/autogroup: Fix failure to set cpu.rt_runtime_usPeter Zijlstra2015-02-182-5/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Because task_group() uses a cache of autogroup_task_group(), whose output depends on sched_class, switching classes can generate problems. In particular, when started as fair, the cache points to the autogroup, so when switching to RT the tg_rt_schedulable() test fails for every cpu.rt_{runtime,period}_us change because now the autogroup has tasks and no runtime. Furthermore, going back to the previous semantics of varying task_group() with sched_class has the down-side that the sched_debug output varies as well, even though the task really is in the autogroup. Therefore add an autogroup exception to tg_has_rt_tasks() -- such that both (all) task_group() usages in sched/core now have one. And remove all the remnants of the variable task_group() output. Reported-by: Zefan Li <lizefan@huawei.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Stefan Bader <stefan.bader@canonical.com> Fixes: 8323f26ce342 ("sched: Fix race in task_group()") Link: http://lkml.kernel.org/r/20150209112237.GR5029@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | sched/dl: Do update_rq_clock() in yield_task_dl()Kirill Tkhai2015-02-181-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | update_curr_dl() needs actual rq clock. Signed-off-by: Kirill Tkhai <ktkhai@parallels.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1423040972.18770.10.camel@tkhai Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | sched: Prevent recursion in io_schedule()NeilBrown2015-02-181-19/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | io_schedule() calls blk_flush_plug() which, depending on the contents of current->plug, can initiate arbitrary blk-io requests. Note that this contrasts with blk_schedule_flush_plug() which requires all non-trivial work to be handed off to a separate thread. This makes it possible for io_schedule() to recurse, and initiating block requests could possibly call mempool_alloc() which, in times of memory pressure, uses io_schedule(). Apart from any stack usage issues, io_schedule() will not behave correctly when called recursively as delayacct_blkio_start() does not allow for repeated calls. So: - use ->in_iowait to detect recursion. Set it earlier, and restore it to the old value. - move the call to "raw_rq" after the call to blk_flush_plug(). As this is some sort of per-cpu thing, we want some chance that we are on the right CPU - When io_schedule() is called recurively, use blk_schedule_flush_plug() which cannot further recurse. - as this makes io_schedule() a lot more complex and as io_schedule() must match io_schedule_timeout(), but all the changes in io_schedule_timeout() and make io_schedule a simple wrapper for that. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> [ Moved the now rudimentary io_schedule() into sched.h. ] Cc: Jens Axboe <axboe@kernel.dk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Tony Battersby <tonyb@cybernetics.com> Link: http://lkml.kernel.org/r/20150213162600.059fffb2@notabene.brown Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | sched/completion: Serialize completion_done() with complete()Oleg Nesterov2015-02-181-2/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit de30ec47302c "Remove unnecessary ->wait.lock serialization when reading completion state" was not correct, without lock/unlock the code like stop_machine_from_inactive_cpu() while (!completion_done()) cpu_relax(); can return before complete() finishes its spin_unlock() which writes to this memory. And spin_unlock_wait(). While at it, change try_wait_for_completion() to use READ_ONCE(). Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reported-by: Davidlohr Bueso <dave@stgolabs.net> Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> [ Added a comment with the barrier. ] Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nicholas Mc Guire <der.herr@hofr.at> Cc: raghavendra.kt@linux.vnet.ibm.com Cc: waiman.long@hp.com Fixes: de30ec47302c ("sched/completion: Remove unnecessary ->wait.lock serialization when reading completion state") Link: http://lkml.kernel.org/r/20150212195913.GA30430@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | sched: Fix preempt_schedule_common() triggering tracing recursionFrederic Weisbecker2015-02-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since the function graph tracer needs to disable preemption, it might call preempt_schedule() after reenabling it if something triggered the need for rescheduling in between. Therefore we can't trace preempt_schedule() itself because we would face a function tracing recursion otherwise as the tracer is always called before PREEMPT_ACTIVE gets set to prevent that recursion. This is why preempt_schedule() is tagged as "notrace". But the same issue applies to every function called by preempt_schedule() before PREEMPT_ACTIVE is actually set. And preempt_schedule_common() is one such example. Unfortunately we forgot to tag it as notrace as well and as a result we are encountering tracing recursion since it got introduced by: a18b5d0181923 ("sched: Fix missing preemption opportunity") Let's fix that by applying the appropriate function tag to preempt_schedule_common(). Reported-by: Huang Ying <ying.huang@intel.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1424110807-15057-1-git-send-email-fweisbec@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | sched/dl: Prevent enqueue of a sleeping task in dl_task_timer()Kirill Tkhai2015-02-181-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A deadline task may be throttled and dequeued at the same time. This happens, when it becomes throttled in schedule(), which is called to go to sleep: current->state = TASK_INTERRUPTIBLE; schedule() deactivate_task() dequeue_task_dl() update_curr_dl() start_dl_timer() __dequeue_task_dl() prev->on_rq = 0; Later the timer fires, but the task is still dequeued: dl_task_timer() enqueue_task_dl() /* queues on dl_rq; on_rq remains 0 */ Someone wakes it up: try_to_wake_up() enqueue_dl_entity() BUG_ON(on_dl_rq()) Patch fixes this problem, it prevents queueing !on_rq tasks on dl_rq. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Kirill Tkhai <ktkhai@parallels.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> [ Wrote comment. ] Cc: Juri Lelli <juri.lelli@arm.com> Fixes: 1019a359d3dc ("sched/deadline: Fix stale yield state") Link: http://lkml.kernel.org/r/1374601424090314@web4j.yandex.ru Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | sched: Make dl_task_time() use task_rq_lock()Peter Zijlstra2015-02-183-85/+79
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kirill reported that a dl task can be throttled and dequeued at the same time. This happens, when it becomes throttled in schedule(), which is called to go to sleep: current->state = TASK_INTERRUPTIBLE; schedule() deactivate_task() dequeue_task_dl() update_curr_dl() start_dl_timer() __dequeue_task_dl() prev->on_rq = 0; This invalidates the assumption from commit 0f397f2c90ce ("sched/dl: Fix race in dl_task_timer()"): "The only reason we don't strictly need ->pi_lock now is because we're guaranteed to have p->state == TASK_RUNNING here and are thus free of ttwu races". And therefore we have to use the full task_rq_lock() here. This further amends the fact that we forgot to update the rq lock loop for TASK_ON_RQ_MIGRATE, from commit cca26e8009d1 ("sched: Teach scheduler to understand TASK_ON_RQ_MIGRATING state"). Reported-by: Kirill Tkhai <ktkhai@parallels.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Juri Lelli <juri.lelli@arm.com> Link: http://lkml.kernel.org/r/20150217123139.GN5029@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | sched: Clarify ordering between task_rq_lock() and move_queued_task()Peter Zijlstra2015-02-181-0/+16
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There was a wee bit of confusion around the exact ordering here; clarify things. Reported-by: Kirill Tkhai <ktkhai@parallels.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20150217121258.GM5029@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
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*-. | | Merge branches 'core-urgent-for-linus' and 'irq-urgent-for-linus' of ↵Linus Torvalds2015-02-211-0/+1
|\ \| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull rcu fix and x86 irq fix from Ingo Molnar: - Fix a bug that caused an RCU warning splat. - Two x86 irq related fixes: a hotplug crash fix and an ACPI IRQ registry fix. * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rcu: Clear need_qs flag to prevent splat * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/irq: Check for valid irq descriptor in check_irq_vectors_for_cpu_disable() x86/irq: Fix regression caused by commit b568b8601f05
| * | | Merge branch 'rcu/next' of ↵Ingo Molnar2015-02-181-0/+1
| |\ \ \ | | |/ / | |/| | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/urgent Pull RCU fix from Paul E. McKenney. Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | rcu: Clear need_qs flag to prevent splatPaul E. McKenney2015-02-121-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the scheduling-clock interrupt sets the current tasks need_qs flag, but if the current CPU passes through a quiescent state in the meantime, then rcu_preempt_qs() will fail to clear the need_qs flag, which can fool RCU into thinking that additional rcu_read_unlock_special() processing is needed. This commit therefore clears the need_qs flag before checking for additional processing. For this problem to occur, we need rcu_preempt_data.passed_quiesce equal to true and current->rcu_read_unlock_special.b.need_qs also equal to true. This condition can occur as follows: 1. CPU 0 is aware of the current preemptible RCU grace period, but has not yet passed through a quiescent state. Among other things, this means that rcu_preempt_data.passed_quiesce is false. 2. Task A running on CPU 0 enters a preemptible RCU read-side critical section. 3. CPU 0 takes a scheduling-clock interrupt, which notices the RCU read-side critical section and the need for a quiescent state, and thus sets current->rcu_read_unlock_special.b.need_qs to true. 4. Task A is preempted, enters the scheduler, eventually invoking rcu_preempt_note_context_switch() which in turn invokes rcu_preempt_qs(). Because rcu_preempt_data.passed_quiesce is false, control enters the body of the "if" statement, which sets rcu_preempt_data.passed_quiesce to true. 5. At this point, CPU 0 takes an interrupt. The interrupt handler contains an RCU read-side critical section, and the rcu_read_unlock() notes that current->rcu_read_unlock_special is nonzero, and thus invokes rcu_read_unlock_special(). 6. Once in rcu_read_unlock_special(), the fact that current->rcu_read_unlock_special.b.need_qs is true becomes apparent, so rcu_read_unlock_special() invokes rcu_preempt_qs(). Recursively, given that we interrupted out of that same function in the preceding step. 7. Because rcu_preempt_data.passed_quiesce is now true, rcu_preempt_qs() does nothing, and simply returns. 8. Upon return to rcu_read_unlock_special(), it is noted that current->rcu_read_unlock_special is still nonzero (because the interrupted rcu_preempt_qs() had not yet gotten around to clearing current->rcu_read_unlock_special.b.need_qs). 9. Execution proceeds to the WARN_ON_ONCE(), which notes that we are in an interrupt handler and thus duly splats. The solution, as noted above, is to make rcu_read_unlock_special() clear out current->rcu_read_unlock_special.b.need_qs after calling rcu_preempt_qs(). The interrupted rcu_preempt_qs() will clear it again, but this is harmless. The worst that happens is that we clobber another attempt to set this field, but this is not a problem because we just got done reporting a quiescent state. Reported-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> [ paulmck: Fix embarrassing build bug noted by Sasha Levin. ] Tested-by: Sasha Levin <sasha.levin@oracle.com>
* | | | Merge tag 'for_linux-3.20-rc1' of ↵Linus Torvalds2015-02-215-23/+64
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb Pull kgdb/kdb updates from Jason Wessel: "KGDB/KDB New: - KDB: improved searching - No longer enter debug core on panic if panic timeout is set KGDB/KDB regressions / cleanups - fix pdf doc build errors - prevent junk characters on kdb console from printk levels" * tag 'for_linux-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb: kgdb, docs: Fix <para> pdfdocs build errors debug: prevent entering debug mode on panic/exception. kdb: Const qualifier for kdb_getstr's prompt argument kdb: Provide forward search at more prompt kdb: Fix a prompt management bug when using | grep kdb: Remove stack dump when entering kgdb due to NMI kdb: Avoid printing KERN_ levels to consoles kdb: Fix off by one error in kdb_cpu() kdb: fix incorrect counts in KDB summary command output
| * | | | debug: prevent entering debug mode on panic/exception.Colin Cross2015-02-191-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On non-developer devices, kgdb prevents the device from rebooting after a panic. Incase of panics and exceptions, to allow the device to reboot, prevent entering debug mode to avoid getting stuck waiting for the user to interact with debugger. To avoid entering the debugger on panic/exception without any extra configuration, panic_timeout is being used which can be set via /proc/sys/kernel/panic at run time and CONFIG_PANIC_TIMEOUT sets the default value. Setting panic_timeout indicates that the user requested machine to perform unattended reboot after panic. We dont want to get stuck waiting for the user input incase of panic. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: kgdb-bugreport@lists.sourceforge.net Cc: linux-kernel@vger.kernel.org Cc: Android Kernel Team <kernel-team@android.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Colin Cross <ccross@android.com> [Kiran: Added context to commit message. panic_timeout is used instead of break_on_panic and break_on_exception to honor CONFIG_PANIC_TIMEOUT Modified the commit as per community feedback] Signed-off-by: Kiran Raparthy <kiran.kumar@linaro.org> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * | | | kdb: Const qualifier for kdb_getstr's prompt argumentDaniel Thompson2015-02-192-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All current callers of kdb_getstr() can pass constant pointers via the prompt argument. This patch adds a const qualification to make explicit the fact that this is safe. Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * | | | kdb: Provide forward search at more promptDaniel Thompson2015-02-193-5/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently kdb allows the output of comamnds to be filtered using the | grep feature. This is useful but does not permit the output emitted shortly after a string match to be examined without wading through the entire unfiltered output of the command. Such a feature is particularly useful to navigate function traces because these traces often have a useful trigger string *before* the point of interest. This patch reuses the existing filtering logic to introduce a simple forward search to kdb that can be triggered from the more prompt. Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * | | | kdb: Fix a prompt management bug when using | grepDaniel Thompson2015-02-191-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently when the "| grep" feature is used to filter the output of a command then the prompt is not displayed for the subsequent command. Likewise any characters typed by the user are also not echoed to the display. This rather disconcerting problem eventually corrects itself when the user presses Enter and the kdb_grepping_flag is cleared as kdb_parse() tries to make sense of whatever they typed. This patch resolves the problem by moving the clearing of this flag from the middle of command processing to the beginning. Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * | | | kdb: Remove stack dump when entering kgdb due to NMIDaniel Thompson2015-02-191-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Issuing a stack dump feels ergonomically wrong when entering due to NMI. Entering due to NMI is normally a reaction to a user request, either the NMI button on a server or a "magic knock" on a UART. Therefore the backtrace behaviour on entry due to NMI should be like SysRq-g (no stack dump) rather than like oops. Note also that the stack dump does not offer any information that cannot be trivial retrieved using the 'bt' command. Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * | | | kdb: Avoid printing KERN_ levels to consolesDaniel Thompson2015-02-192-10/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently when kdb traps printk messages then the raw log level prefix (consisting of '\001' followed by a numeral) does not get stripped off before the message is issued to the various I/O handlers supported by kdb. This causes annoying visual noise as well as causing problems grepping for ^. It is also a change of behaviour compared to normal usage of printk() usage. For example <SysRq>-h ends up with different output to that of kdb's "sr h". This patch addresses the problem by stripping log levels from messages before they are issued to the I/O handlers. printk() which can also act as an i/o handler in some cases is special cased; if the caller provided a log level then the prefix will be preserved when sent to printk(). The addition of non-printable characters to the output of kdb commands is a regression, albeit and extremely elderly one, introduced by commit 04d2c8c83d0e ("printk: convert the format for KERN_<LEVEL> to a 2 byte pattern"). Note also that this patch does *not* restore the original behaviour from v3.5. Instead it makes printk() from within a kdb command display the message without any prefix (i.e. like printk() normally does). Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Joe Perches <joe@perches.com> Cc: stable@vger.kernel.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * | | | kdb: Fix off by one error in kdb_cpu()Jason Wessel2015-02-192-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There was a follow on replacement patch against the prior "kgdb: Timeout if secondary CPUs ignore the roundup". See: https://lkml.org/lkml/2015/1/7/442 This patch is the delta vs the patch that was committed upstream: * Fix an off-by-one error in kdb_cpu(). * Replace NR_CPUS with CONFIG_NR_CPUS to tell checkpatch that we really want a static limit. * Removed the "KGDB: " prefix from the pr_crit() in debug_core.c (kgdb-next contains a patch which introduced pr_fmt() to this file to the tag will now be applied automatically). Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: <stable@vger.kernel.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * | | | kdb: fix incorrect counts in KDB summary command outputJay Lan2015-02-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The output of KDB 'summary' command should report MemTotal, MemFree and Buffers output in kB. Current codes report in unit of pages. A define of K(x) as is defined in the code, but not used. This patch would apply the define to convert the values to kB. Please include me on Cc on replies. I do not subscribe to linux-kernel. Signed-off-by: Jay Lan <jlan@sgi.com> Cc: <stable@vger.kernel.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
* | | | | Merge branch 'kbuild' of ↵Linus Torvalds2015-02-191-31/+5
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild Pull kbuild updates from Michal Marek: - several cleanups in kbuild - serialize multiple *config targets so that 'make defconfig kvmconfig' works - The cc-ifversion macro got support for an else-branch * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: kbuild,gcov: simplify kernel/gcov/Makefile more kbuild: allow cc-ifversion to have the argument for false condition kbuild,gcov: simplify kernel/gcov/Makefile kbuild,gcov: remove unnecessary workaround kbuild: do not add $(call ...) to invoke cc-version or cc-fullversion kbuild: fix cc-ifversion macro kbuild: drop $(version_h) from MRPROPER_FILES kbuild: use mixed-targets when two or more config targets are given kbuild: remove redundant line from bounds.h/asm-offsets.h kbuild: merge bounds.h and asm-offsets.h rules kbuild: Drop support for clean-rule
| * | | | | kbuild,gcov: simplify kernel/gcov/Makefile moreMasahiro Yamada2015-01-091-19/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CONFIG_GCOV_FORMAT_3_4 / _4_7 / _AUTODETECT are exclusive. Compare the CC version only when _AUTODETECT is enabled. This change should have no impact. Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Michal Marek <mmarek@suse.cz>
| * | | | | kbuild,gcov: simplify kernel/gcov/MakefileMasahiro Yamada2015-01-091-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kbuild descends into kernel/gcov/ directory only when CONFIG_GCOV_KERNEL is enabled. (See kernel/Makefile) CONFIG_GCOV_KERNEL check can be omitted in kernel/gcov/Makefile. Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Michal Marek <mmarek@suse.cz>
| * | | | | kbuild,gcov: remove unnecessary workaroundMasahiro Yamada2015-01-091-12/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit 371fdc77af44 (kbuild: collect shorthands into scripts/Kbuild.include), scripts/Makefile.clean includes scripts/Kbuild.include. The workaround and the comment block in kernel/gcov/Makefile are no longer necessary. Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com> Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Michal Marek <mmarek@suse.cz>
| * | | | | kbuild: do not add $(call ...) to invoke cc-version or cc-fullversionMasahiro Yamada2015-01-091-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The macros cc-version, cc-fullversion and ld-version take no argument. It is not necessary to add $(call ...) to invoke them. Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com> Acked-by: Helge Deller <deller@gmx.de> [parisc] Signed-off-by: Michal Marek <mmarek@suse.cz>
* | | | | | Merge branch 'getname2' of ↵Linus Torvalds2015-02-182-151/+37
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull getname/putname updates from Al Viro: "Rework of getname/getname_kernel/etc., mostly from Paul Moore. Gets rid of quite a pile of kludges between namei and audit..." * 'getname2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: audit: replace getname()/putname() hacks with reference counters audit: fix filename matching in __audit_inode() and __audit_inode_child() audit: enable filename recording via getname_kernel() simpler calling conventions for filename_mountpoint() fs: create proper filename objects using getname_kernel() fs: rework getname_kernel to handle up to PATH_MAX sized filenames cut down the number of do_path_lookup() callers
| * | | | | | audit: replace getname()/putname() hacks with reference countersPaul Moore2015-01-232-109/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to ensure that filenames are not released before the audit subsystem is done with the strings there are a number of hacks built into the fs and audit subsystems around getname() and putname(). To say these hacks are "ugly" would be kind. This patch removes the filename hackery in favor of a more conventional reference count based approach. The diffstat below tells most of the story; lots of audit/fs specific code is replaced with a traditional reference count based approach that is easily understood, even by those not familiar with the audit and/or fs subsystems. CC: viro@zeniv.linux.org.uk CC: linux-fsdevel@vger.kernel.org Signed-off-by: Paul Moore <pmoore@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | | | | | audit: fix filename matching in __audit_inode() and __audit_inode_child()Paul Moore2015-01-231-9/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In all likelihood there were some subtle, and perhaps not so subtle, bugs with filename matching in audit_inode() and audit_inode_child() for some time, however, recent changes to the audit filename code have definitely broken the filename matching code. The breakage could result in duplicate filenames in the audit log and other odd audit record entries. This patch fixes the filename matching code and restores some sanity to the filename audit records. CC: viro@zeniv.linux.org.uk CC: linux-fsdevel@vger.kernel.org Signed-off-by: Paul Moore <pmoore@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | | | | | audit: enable filename recording via getname_kernel()Paul Moore2015-01-231-37/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Enable recording of filenames in getname_kernel() and remove the kludgy workaround in __audit_inode() now that we have proper filename logging for kernel users. CC: viro@zeniv.linux.org.uk CC: linux-fsdevel@vger.kernel.org Signed-off-by: Paul Moore <pmoore@redhat.com> Reviewed-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | | | | | Merge branch 'for-linus' of ↵Linus Torvalds2015-02-172-52/+47
|\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull misc VFS updates from Al Viro: "This cycle a lot of stuff sits on topical branches, so I'll be sending more or less one pull request per branch. This is the first pile; more to follow in a few. In this one are several misc commits from early in the cycle (before I went for separate branches), plus the rework of mntput/dput ordering on umount, switching to use of fs_pin instead of convoluted games in namespace_unlock()" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: switch the IO-triggering parts of umount to fs_pin new fs_pin killing logics allow attaching fs_pin to a group not associated with some superblock get rid of the second argument of acct_kill() take count and rcu_head out of fs_pin dcache: let the dentry count go down to zero without taking d_lock pull bumping refcount into ->kill() kill pin_put() mode_t whack-a-mole: chelsio file->f_path.dentry is pinned down for as long as the file is open... get rid of lustre_dump_dentry() gut proc_register() a bit kill d_validate() ncpfs: get rid of d_validate() nonsense selinuxfs: don't open-code d_genocide()
| * | | | | | | new fs_pin killing logicsAl Viro2015-01-261-47/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | | | | | | get rid of the second argument of acct_kill()Al Viro2015-01-261-10/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace the old ns->bacct only with NULL and only if it still points to acct. And assign the new value to it *before* calling acct_kill() in acct_on(). That way we don't need to pass the new acct to acct_kill(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | | | | | | take count and rcu_head out of fs_pinAl Viro2015-01-261-6/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | | | | | | pull bumping refcount into ->kill()Al Viro2015-01-261-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | there will be one more change of ->kill() calling conventions; this isn't final. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | | | | | | kill pin_put()Al Viro2015-01-261-4/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | | | | | | file->f_path.dentry is pinned down for as long as the file is open...Al Viro2015-01-261-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | | | | | | Merge branch 'akpm' (patches from Andrew)Linus Torvalds2015-02-175-18/+23
|\ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge yet more updates from Andrew Morton: - a pile of minor fs fixes and cleanups - kexec updates - random misc fixes in various places: vmcore, rbtree, eventfd, ipc, seccomp. - a series of python-based kgdb helper scripts * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (58 commits) seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNO samples/seccomp: improve label helper ipc,sem: use current->state helpers scripts/gdb: disable pagination while printing from breakpoint handler scripts/gdb: define maintainer scripts/gdb: convert CpuList to generator function scripts/gdb: convert ModuleList to generator function scripts/gdb: use a generator instead of iterator for task list scripts/gdb: ignore byte-compiled python files scripts/gdb: port to python3 / gdb7.7 scripts/gdb: add basic documentation scripts/gdb: add lx-lsmod command scripts/gdb: add class to iterate over CPU masks scripts/gdb: add lx_current convenience function scripts/gdb: add internal helper and convenience function for per-cpu lookup scripts/gdb: add get_gdbserver_type helper scripts/gdb: add internal helper and convenience function to retrieve thread_info scripts/gdb: add is_target_arch helper scripts/gdb: add helper and convenience function to look up tasks scripts/gdb: add task iteration class ...
| * | | | | | | | seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNOKees Cook2015-02-171-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The value resulting from the SECCOMP_RET_DATA mask could exceed MAX_ERRNO when setting errno during a SECCOMP_RET_ERRNO filter action. This makes sure we have a reliable value being set, so that an invalid errno will not be ignored by userspace. Signed-off-by: Kees Cook <keescook@chromium.org> Reported-by: Dmitry V. Levin <ldv@altlinux.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Will Drewry <wad@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>