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* Hook into kernel/exit.c to force exiting RT tasks into best-effort modeBjoern Brandenburg2015-08-09
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* Protect LITMUS^RT tasks from re-nicingBjoern Brandenburg2015-08-09
| | | | | Assigning a nice value to LITMUS^RT tasks is meaningless. Bail out early.
* Don't call set_tsk_need_resched() on remote LITMUS^RT taskBjoern Brandenburg2015-08-09
| | | | This patch fixes a BUG_ON() in litmus/preempt.c.
* Hook into SCHED_DEADLINE to protect LITMUS^RT tasksBjoern Brandenburg2015-08-09
| | | | | SCHED_DEADLINE should not preempt LITMUS^RT tasks, as the LITMUS^RT scheduling class is positioned above the SCHED_DEADLINE policy.
* Hook into rt scheduling class to protect LITMUS^RT tasksBjoern Brandenburg2015-08-09
| | | | | | The rt scheduling class thinks it's the highest-priority scheduling class around, next to SCHED_DEADLINE. It is not in LITMUS^RT. Don't go preempting remote cores that run SCHED_LITMUS tasks.
* Don't trigger load balancer in scheduler tick for LITMUS^RTBjoern Brandenburg2015-08-09
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* Hook into finish_switch()Bjoern Brandenburg2015-08-09
| | | | To keep track of stack usage and to notify plugin, if necessary.
* Reset SCHED_LITMUS scheduling class on forkBjoern Brandenburg2015-08-09
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* Block sched_setaffinity() for SCHED_LITMUS tasksBjoern Brandenburg2015-08-09
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* Integrate LITMUS^RT scheduling class with sched_setschedulerBjoern Brandenburg2015-08-09
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* Disable cut-to-CFS optimization in Linux schedulerBjoern Brandenburg2015-08-09
| | | | | Global plugins require that the plugin be called even if there currently is no real-time task executing on the local core.
* Integrate LITMUS^RT with try_to_wake_up() pathBjoern Brandenburg2015-08-09
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* Make LITMUS^RT scheduling class the highest-priority scheduling classBjoern Brandenburg2015-08-09
| | | | | | Needs to be above stop_machine_class for legacy reasons; the main plugins were developed before stop_machine_class was introduced and assume that they are the highest-priority scheduling class.
* Add LITMUS^RT scheduling class in kernel/sched/MakefileBjoern Brandenburg2015-08-09
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* Introduce LITMUS^RT runqueue dummy into struct rqBjoern Brandenburg2015-08-09
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* Integrate SRP ceiling blocking callback with Linux schedulerBjoern Brandenburg2015-08-09
| | | | Check whether a suspension is required at end of schedule().
* Hookup sched_trace_XXX() tracing in Linux schedulerBjoern Brandenburg2015-08-09
| | | | This patch adds context switch tracing to the main Linux scheduler.
* Augment rt_task() with is_realtime()Bjoern Brandenburg2015-08-09
| | | | | | | | | | | Whenever the kernel checks for rt_task() to avoid delaying real-time tasks, we want it to also not delay LITMUS^RT tasks. Hence, most calls to rt_task() should be matched by an equivalent call to is_realtime(). Notably, this affects the implementations of select() and nanosleep(), which use timer_slack_ns when setting up timers for non-real-time tasks.
* Hook into fork(), exec(), and exit()Bjoern Brandenburg2015-08-09
| | | | | Allow LITMUS^RT to do some work when a process is created or terminated.
* Call sched_state_task_picked() from pick_next_task_stop()Bjoern Brandenburg2015-08-09
| | | | | Otherwise, the scheduler state machine becomes confused (and goes into a rescheduling loop) when stop-machine is triggered.
* Integrate preemption state machine with Linux schedulerBjoern Brandenburg2015-08-09
| | | | Track when a processor is going to schedule "soon".
* Add LITMUS^RT core implementationBjoern Brandenburg2015-08-09
| | | | | | | | | | | | | This patch adds the core of LITMUS^RT: - library functionality (heaps, rt_domain, prioritization, etc.) - budget enforcement logic - job management - system call backends - virtual devices (control page, etc.) - scheduler plugin API (and dummy plugin) This code compiles, but is not yet integrated with the rest of Linux.
* Add hrtimer_start_on() supportBjoern Brandenburg2015-08-09
| | | | | | This patch adds hrtimer_start_on(), which allows arming timers on remote CPUs. This is needed to avoided timer interrupts on "shielded" CPUs and is also useful for implementing semi-partitioned schedulers.
* Add TRACE() debug tracing supportBjoern Brandenburg2015-08-09
| | | | | | | This patch adds the infrastructure for the TRACE() debug macro. Conflicts: kernel/printk.c
* Add SCHED, SCHED2, TICK, and CXS overhead tracepointsBjoern Brandenburg2015-08-09
| | | | | | | This patch integrates the overhead tracepoints into the Linux scheduler that are compatible with plain vanilla Linux (i.e., not specific to LITMUS^RT plugins). This can be used to measure the overheads of an otherwise unmodified kernel.
* Integrate ft_irq_fired() with LinuxBjoern Brandenburg2015-08-09
| | | | | This patch hooks up Feather-Trace's ft_irq_fired() handler with Linux's interrupt handling infrastructure.
* genirq: devres: Fix testing return value of request_any_context_irq()Axel Lin2015-07-21
| | | | | | | | | | | | | | | | | | | commit 63781394c540dd9e666a6b21d70b64dd52bce76e upstream. request_any_context_irq() returns a negative value on failure. It returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED on success. So fix testing return value of request_any_context_irq(). Also fixup the return value of devm_request_any_context_irq() to make it consistent with request_any_context_irq(). Fixes: 0668d3065128 ("genirq: Add devm_request_any_context_irq()") Signed-off-by: Axel Lin <axel.lin@ingics.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Link: http://lkml.kernel.org/r/1431334978.17783.4.camel@ingics.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* livepatch: add module locking around kallsyms callsMiroslav Benes2015-07-21
| | | | | | | | | | | | | | | | | | | commit 9a1bd63cdae4b623494c4ebaf723a91c35ec49fb upstream. The list of loaded modules is walked through in module_kallsyms_on_each_symbol (called by kallsyms_on_each_symbol). The module_mutex lock should be acquired to prevent potential corruptions in the list. This was uncovered with new lockdep asserts in module code introduced by the commit 0be964be0d45 ("module: Sanitize RCU usage and locking") in recent next- trees. Signed-off-by: Miroslav Benes <mbenes@suse.cz> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* rcu: Correctly handle non-empty Tiny RCU callback list with none readyPaul E. McKenney2015-07-21
| | | | | | | | | | | | | | | | | | | | | | | | | | commit 6e91f8cb138625be96070b778d9ba71ce520ea7e upstream. If, at the time __rcu_process_callbacks() is invoked, there are callbacks in Tiny RCU's callback list, but none of them are ready to be invoked, the current list-management code will knit the non-ready callbacks out of the list. This can result in hangs and possibly worse. This commit therefore inserts a check for there being no callbacks that can be invoked immediately. This bug is unlikely to occur -- you have to get a new callback between the time rcu_sched_qs() or rcu_bh_qs() was called, but before we get to __rcu_process_callbacks(). It was detected by the addition of RCU-bh testing to rcutorture, which in turn was instigated by Iftekhar Ahmed's mutation testing. Although this bug was made much more likely by 915e8a4fe45e (rcu: Remove fastpath from __rcu_process_callbacks()), this did not cause the bug, but rather made it much more probable. That said, it takes more than 40 hours of rcutorture testing, on average, for this bug to appear, so this fix cannot be considered an emergency. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysfs: Create mountpoints with sysfs_create_mount_pointEric W. Biederman2015-07-21
| | | | | | | | | | | | | | | | | | | | | | | | | | commit f9bb48825a6b5d02f4cabcc78967c75db903dcdc upstream. This allows for better documentation in the code and it allows for a simpler and fully correct version of fs_fully_visible to be written. The mount points converted and their filesystems are: /sys/hypervisor/s390/ s390_hypfs /sys/kernel/config/ configfs /sys/kernel/debug/ debugfs /sys/firmware/efi/efivars/ efivarfs /sys/fs/fuse/connections/ fusectl /sys/fs/pstore/ pstore /sys/kernel/tracing/ tracefs /sys/fs/cgroup/ cgroup /sys/kernel/security/ securityfs /sys/fs/selinux/ selinuxfs /sys/fs/smackfs/ smackfs Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* sysctl: Allow creating permanently empty directories that serve as mountpoints.Eric W. Biederman2015-07-21
| | | | | | | | | | | | | | | | | | commit f9bd6733d3f11e24f3949becf277507d422ee1eb upstream. Add a magic sysctl table sysctl_mount_point that when used to create a directory forces that directory to be permanently empty. Update the code to use make_empty_dir_inode when accessing permanently empty directories. Update the code to not allow adding to permanently empty directories. Update /proc/sys/fs/binfmt_misc to be a permanently empty directory. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* perf: Fix ring_buffer_attach() RCU sync, againOleg Nesterov2015-06-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 2f993cf093643b98477c421fa2b9a98dcc940323 upstream. While looking for other users of get_state/cond_sync. I Found ring_buffer_attach() and it looks obviously buggy? Don't we need to ensure that we have "synchronize" _between_ list_del() and list_add() ? IOW. Suppose that ring_buffer_attach() preempts right_after get_state_synchronize_rcu() and gp completes before spin_lock(). In this case cond_synchronize_rcu() does nothing and we reuse ->rb_entry without waiting for gp in between? It also moves the ->rcu_pending check under "if (rb)", to make it more readable imo. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dave@stgolabs.net Cc: der.herr@hofr.at Cc: josh@joshtriplett.org Cc: tj@kernel.org Fixes: b69cf53640da ("perf: Fix a race between ring_buffer_detach() and ring_buffer_attach()") Link: http://lkml.kernel.org/r/20150530200425.GA15748@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'trace-fix-filter-4.1-rc8' of ↵Linus Torvalds2015-06-18
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing filter fix from Steven Rostedt: "Vince Weaver reported a warning when he added perf event filters into his fuzzer tests. There's a missing check of balanced operations when parenthesis are used, and this triggers a WARN_ON() and when reading the failure, the filter reports no failure occurred. The operands were not being checked if they match, this adds that" * tag 'trace-fix-filter-4.1-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Have filter check for balanced ops
| * tracing: Have filter check for balanced opsSteven Rostedt2015-06-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the following filter is used it causes a warning to trigger: # cd /sys/kernel/debug/tracing # echo "((dev==1)blocks==2)" > events/ext4/ext4_truncate_exit/filter -bash: echo: write error: Invalid argument # cat events/ext4/ext4_truncate_exit/filter ((dev==1)blocks==2) ^ parse_error: No error ------------[ cut here ]------------ WARNING: CPU: 2 PID: 1223 at kernel/trace/trace_events_filter.c:1640 replace_preds+0x3c5/0x990() Modules linked in: bnep lockd grace bluetooth ... CPU: 3 PID: 1223 Comm: bash Tainted: G W 4.1.0-rc3-test+ #450 Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v02.05 05/07/2012 0000000000000668 ffff8800c106bc98 ffffffff816ed4f9 ffff88011ead0cf0 0000000000000000 ffff8800c106bcd8 ffffffff8107fb07 ffffffff8136b46c ffff8800c7d81d48 ffff8800d4c2bc00 ffff8800d4d4f920 00000000ffffffea Call Trace: [<ffffffff816ed4f9>] dump_stack+0x4c/0x6e [<ffffffff8107fb07>] warn_slowpath_common+0x97/0xe0 [<ffffffff8136b46c>] ? _kstrtoull+0x2c/0x80 [<ffffffff8107fb6a>] warn_slowpath_null+0x1a/0x20 [<ffffffff81159065>] replace_preds+0x3c5/0x990 [<ffffffff811596b2>] create_filter+0x82/0xb0 [<ffffffff81159944>] apply_event_filter+0xd4/0x180 [<ffffffff81152bbf>] event_filter_write+0x8f/0x120 [<ffffffff811db2a8>] __vfs_write+0x28/0xe0 [<ffffffff811dda43>] ? __sb_start_write+0x53/0xf0 [<ffffffff812e51e0>] ? security_file_permission+0x30/0xc0 [<ffffffff811dc408>] vfs_write+0xb8/0x1b0 [<ffffffff811dc72f>] SyS_write+0x4f/0xb0 [<ffffffff816f5217>] system_call_fastpath+0x12/0x6a ---[ end trace e11028bd95818dcd ]--- Worse yet, reading the error message (the filter again) it says that there was no error, when there clearly was. The issue is that the code that checks the input does not check for balanced ops. That is, having an op between a closed parenthesis and the next token. This would only cause a warning, and fail out before doing any real harm, but it should still not caues a warning, and the error reported should work: # cd /sys/kernel/debug/tracing # echo "((dev==1)blocks==2)" > events/ext4/ext4_truncate_exit/filter -bash: echo: write error: Invalid argument # cat events/ext4/ext4_truncate_exit/filter ((dev==1)blocks==2) ^ parse_error: Meaningless filter expression And give no kernel warning. Link: http://lkml.kernel.org/r/20150615175025.7e809215@gandalf.local.home Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: stable@vger.kernel.org # 2.6.31+ Reported-by: Vince Weaver <vincent.weaver@maine.edu> Tested-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | Merge branch 'locking-urgent-for-linus' of ↵Linus Torvalds2015-06-14
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull lockdep fix from Ingo Molnar: "A lockdep/modules unload race fix that can oops" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: lockdep: Fix a race between /proc/lock_stat and module unload
| * | lockdep: Fix a race between /proc/lock_stat and module unloadPeter Zijlstra2015-06-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The lock_class iteration of /proc/lock_stat is not serialized against the lockdep_free_key_range() call from module unload. Therefore it can happen that we find a class of which ->name/->key are no longer valid. There is a further bug in zap_class() that left ->name dangling. Cure this. Use RCU_INIT_POINTER() because NULL. Since lockdep_free_key_range() is rcu_sched serialized, we can read both ->name and ->key under rcu_read_lock_sched() (preempt-disable) and be assured that if we observe a !NULL value it stays safe to use for as long as we hold that lock. If we observe both NULL, skip the entry. Reported-by: Jerome Marchand <jmarchan@redhat.com> Tested-by: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20150602105013.GS3644@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | Merge tag 'trace-rb-bm-fix-4.1-rc7' of ↵Linus Torvalds2015-06-11
|\ \ \ | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull ring buffer benchmark buglet fix from Steven Rostedt: "Wang Long fixed a minor bug in the module parameter for the ring buffer benchmark, where the produce_fifo was being ignored and the producer thread's priority was being set with the consumer_fifo parameter" * tag 'trace-rb-bm-fix-4.1-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ring-buffer-benchmark: Fix the wrong sched_priority of producer
| * | ring-buffer-benchmark: Fix the wrong sched_priority of producerWang Long2015-06-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The producer should be used producer_fifo as its sched_priority, so correct it. Link: http://lkml.kernel.org/r/1433923957-67842-1-git-send-email-long.wanglong@huawei.com Cc: stable@vger.kernel.org # 2.6.33+ Signed-off-by: Wang Long <long.wanglong@huawei.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | | sched, numa: do not hint for NUMA balancing on VM_MIXEDMAP mappingsMel Gorman2015-06-10
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Jovi Zhangwei reported the following problem Below kernel vm bug can be triggered by tcpdump which mmaped a lot of pages with GFP_COMP flag. [Mon May 25 05:29:33 2015] page:ffffea0015414000 count:66 mapcount:1 mapping: (null) index:0x0 [Mon May 25 05:29:33 2015] flags: 0x20047580004000(head) [Mon May 25 05:29:33 2015] page dumped because: VM_BUG_ON_PAGE(compound_order(page) && !PageTransHuge(page)) [Mon May 25 05:29:33 2015] ------------[ cut here ]------------ [Mon May 25 05:29:33 2015] kernel BUG at mm/migrate.c:1661! [Mon May 25 05:29:33 2015] invalid opcode: 0000 [#1] SMP In this case it was triggered by running tcpdump but it's not necessary reproducible on all systems. sudo tcpdump -i bond0.100 'tcp port 4242' -c 100000000000 -w 4242.pcap Compound pages cannot be migrated and it was not expected that such pages be marked for NUMA balancing. This did not take into account that drivers such as net/packet/af_packet.c may insert compound pages into userspace with vm_insert_page. This patch tells the NUMA balancing protection scanner to skip all VM_MIXEDMAP mappings which avoids the possibility that compound pages are marked for migration. Signed-off-by: Mel Gorman <mgorman@suse.de> Reported-by: Jovi Zhangwei <jovi@cloudflare.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds2015-06-05
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "The biggest chunk of the changes are two regression fixes: a HT workaround fix and an event-group scheduling fix. It's been verified with 5 days of fuzzer testing. Other fixes: - eBPF fix - a BIOS breakage detection fix - PMU driver fixes" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/intel/pt: Fix a refactoring bug perf/x86: Tweak broken BIOS rules during check_hw_exists() perf/x86/intel/pt: Untangle pt_buffer_reset_markers() perf: Disallow sparse AUX allocations for non-SG PMUs in overwrite mode perf/x86: Improve HT workaround GP counter constraint perf/x86: Fix event/group validation perf: Fix race in BPF program unregister
| * | perf: Disallow sparse AUX allocations for non-SG PMUs in overwrite modeAlexander Shishkin2015-05-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PMUs that don't support hardware scatter tables require big contiguous chunks of memory and a PMI to switch between them. However, in overwrite using a PMI for this purpose adds extra overhead that the users would like to avoid. Thus, in overwrite mode for such PMUs we can only allow one contiguous chunk for the entire requested buffer. This patch changes the behavior accordingly, so that if the buddy allocator fails to come up with a single high-order chunk for the entire requested buffer, the allocation will fail. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: acme@infradead.org Cc: adrian.hunter@intel.com Cc: hpa@zytor.com Link: http://lkml.kernel.org/r/1432308626-18845-2-git-send-email-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | perf: Fix race in BPF program unregisterAlexei Starovoitov2015-05-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | there is a race between perf_event_free_bpf_prog() and free_trace_kprobe(): __free_event() event->destroy(event) tp_perf_event_destroy() perf_trace_destroy() perf_trace_event_unreg() which is dropping event->tp_event->perf_refcount and allows to proceed in: unregister_trace_kprobe() unregister_kprobe_event() trace_remove_event_call() probe_remove_event_call() free_trace_kprobe() while __free_event does: call_rcu(&event->rcu_head, free_event_rcu); free_event_rcu() perf_event_free_bpf_prog() To fix the race simply move perf_event_free_bpf_prog() before event->destroy(), since event->tp_event is still valid at that point. Note, perf_trace_destroy() is not racing with trace_remove_event_call() since they both grab event_mutex. Reported-by: Wang Nan <wangnan0@huawei.com> Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: lizefan@huawei.com Cc: pi3orama@163.com Fixes: 2541517c32be ("tracing, perf: Implement BPF programs attached to kprobes") Link: http://lkml.kernel.org/r/1431717321-28772-1-git-send-email-ast@plumgrid.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | compat: cleanup coding in compat_get_bitmap() and compat_put_bitmap()Helge Deller2015-06-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the functions compat_get_bitmap() and compat_put_bitmap() the variable nr_compat_longs stores how many compat_ulong_t words should be copied in a loop. The copy loop itself is this: if (nr_compat_longs-- > 0) { if (__get_user(um, umask)) return -EFAULT; } else { um = 0; } Since nr_compat_longs gets unconditionally decremented in each loop and since it's type is unsigned this could theoretically lead to out of bounds accesses to userspace if nr_compat_longs wraps around to (unsigned)(-1). Although the callers currently do not trigger out-of-bounds accesses, we should better implement the loop in a safe way to completely avoid such warp-arounds. Signed-off-by: Helge Deller <deller@gmx.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk>
* | | Merge tag 'fixes-for-linus' of ↵Linus Torvalds2015-05-29
|\ \ \ | |/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull fixes for cpumask and modules from Rusty Russell: "** NOW WITH TESTING! ** Two fixes which got lost in my recent distraction. One is a weird cpumask function which needed to be rewritten, the other is a module bug which is cc:stable" * tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: cpumask_set_cpu_local_first => cpumask_local_spread, lament module: Call module notifier on failure after complete_formation()
| * | module: Call module notifier on failure after complete_formation()Steven Rostedt2015-05-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The module notifier call chain for MODULE_STATE_COMING was moved up before the parsing of args, into the complete_formation() call. But if the module failed to load after that, the notifier call chain for MODULE_STATE_GOING was never called and that prevented the users of those call chains from cleaning up anything that was allocated. Link: http://lkml.kernel.org/r/554C52B9.9060700@gmail.com Reported-by: Pontus Fuchs <pontus.fuchs@gmail.com> Fixes: 4982223e51e8 "module: set nx before marking module MODULE_STATE_COMING" Cc: stable@vger.kernel.org # 3.16+ Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | | Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2015-05-23
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fix from Thomas Gleixner: "One more fix from the timer departement: - Handle division of negative nanosecond values proper on 32bit. A recent cleanup wrecked the sign handling of the dividend and dropped the check for negative divisors" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: ktime: Fix ktime_divns to do signed division
| * | | ktime: Fix ktime_divns to do signed divisionJohn Stultz2015-05-13
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It was noted that the 32bit implementation of ktime_divns() was doing unsigned division and didn't properly handle negative values. And when a ktime helper was changed to utilize ktime_divns, it caused a regression on some IR blasters. See the following bugzilla for details: https://bugzilla.redhat.com/show_bug.cgi?id=1200353 This patch fixes the problem in ktime_divns by checking and preserving the sign bit, and then reapplying it if appropriate after the division, it also changes the return type to a s64 to make it more obvious this is expected. Nicolas also pointed out that negative dividers would cause infinite loops on 32bit systems, negative dividers is unlikely for users of this function, but out of caution this patch adds checks for negative dividers for both 32-bit (BUG_ON) and 64-bit(WARN_ON) versions to make sure no such use cases creep in. [ tglx: Hand an u64 to do_div() to avoid the compiler warning ] Fixes: 166afb64511e 'ktime: Sanitize ktime_to_us/ms conversion' Reported-and-tested-by: Trevor Cordes <trevor@tecnopolis.ca> Signed-off-by: John Stultz <john.stultz@linaro.org> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Josh Boyer <jwboyer@redhat.com> Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/1431118043-23452-1-git-send-email-john.stultz@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | | Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds2015-05-22
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block fixes from Jens Axboe: "Three small fixes that have been picked up the last few weeks. Specifically: - Fix a memory corruption issue in NVMe with malignant user constructed request. From Christoph. - Kill (now) unused blk_queue_bio(), dm was changed to not need this anymore. From Mike Snitzer. - Always use blk_schedule_flush_plug() from the io_schedule() path when flushing a plug, fixing a !TASK_RUNNING warning with md. From Shaohua" * 'for-linus' of git://git.kernel.dk/linux-block: sched: always use blk_schedule_flush_plug in io_schedule_out nvme: fix kernel memory corruption with short INQUIRY buffers block: remove export for blk_queue_bio
| * | | sched: always use blk_schedule_flush_plug in io_schedule_outShaohua Li2015-05-18
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | block plug callback could sleep, so we introduce a parameter 'from_schedule' and corresponding drivers can use it to destinguish a schedule plug flush or a plug finish. Unfortunately io_schedule_out still uses blk_flush_plug(). This causes below output (Note, I added a might_sleep() in raid1_unplug to make it trigger faster, but the whole thing doesn't matter if I add might_sleep). In raid1/10, this can cause deadlock. This patch makes io_schedule_out always uses blk_schedule_flush_plug. This should only impact drivers (as far as I know, raid 1/10) which are sensitive to the 'from_schedule' parameter. [ 370.817949] ------------[ cut here ]------------ [ 370.817960] WARNING: CPU: 7 PID: 145 at ../kernel/sched/core.c:7306 __might_sleep+0x7f/0x90() [ 370.817969] do not call blocking ops when !TASK_RUNNING; state=2 set at [<ffffffff81092fcf>] prepare_to_wait+0x2f/0x90 [ 370.817971] Modules linked in: raid1 [ 370.817976] CPU: 7 PID: 145 Comm: kworker/u16:9 Tainted: G W 4.0.0+ #361 [ 370.817977] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140709_153802- 04/01/2014 [ 370.817983] Workqueue: writeback bdi_writeback_workfn (flush-9:1) [ 370.817985] ffffffff81cd83be ffff8800ba8cb298 ffffffff819dd7af 0000000000000001 [ 370.817988] ffff8800ba8cb2e8 ffff8800ba8cb2d8 ffffffff81051afc ffff8800ba8cb2c8 [ 370.817990] ffffffffa00061a8 000000000000041e 0000000000000000 ffff8800ba8cba28 [ 370.817993] Call Trace: [ 370.817999] [<ffffffff819dd7af>] dump_stack+0x4f/0x7b [ 370.818002] [<ffffffff81051afc>] warn_slowpath_common+0x8c/0xd0 [ 370.818004] [<ffffffff81051b86>] warn_slowpath_fmt+0x46/0x50 [ 370.818006] [<ffffffff81092fcf>] ? prepare_to_wait+0x2f/0x90 [ 370.818008] [<ffffffff81092fcf>] ? prepare_to_wait+0x2f/0x90 [ 370.818010] [<ffffffff810776ef>] __might_sleep+0x7f/0x90 [ 370.818014] [<ffffffffa0000c03>] raid1_unplug+0xd3/0x170 [raid1] [ 370.818024] [<ffffffff81421d9a>] blk_flush_plug_list+0x8a/0x1e0 [ 370.818028] [<ffffffff819e3550>] ? bit_wait+0x50/0x50 [ 370.818031] [<ffffffff819e21b0>] io_schedule_timeout+0x130/0x140 [ 370.818033] [<ffffffff819e3586>] bit_wait_io+0x36/0x50 [ 370.818034] [<ffffffff819e31b5>] __wait_on_bit+0x65/0x90 [ 370.818041] [<ffffffff8125b67c>] ? ext4_read_block_bitmap_nowait+0xbc/0x630 [ 370.818043] [<ffffffff819e3550>] ? bit_wait+0x50/0x50 [ 370.818045] [<ffffffff819e3302>] out_of_line_wait_on_bit+0x72/0x80 [ 370.818047] [<ffffffff810935e0>] ? autoremove_wake_function+0x40/0x40 [ 370.818050] [<ffffffff811de744>] __wait_on_buffer+0x44/0x50 [ 370.818053] [<ffffffff8125ae80>] ext4_wait_block_bitmap+0xe0/0xf0 [ 370.818058] [<ffffffff812975d6>] ext4_mb_init_cache+0x206/0x790 [ 370.818062] [<ffffffff8114bc6c>] ? lru_cache_add+0x1c/0x50 [ 370.818064] [<ffffffff81297c7e>] ext4_mb_init_group+0x11e/0x200 [ 370.818066] [<ffffffff81298231>] ext4_mb_load_buddy+0x341/0x360 [ 370.818068] [<ffffffff8129a1a3>] ext4_mb_find_by_goal+0x93/0x2f0 [ 370.818070] [<ffffffff81295b54>] ? ext4_mb_normalize_request+0x1e4/0x5b0 [ 370.818072] [<ffffffff8129ab67>] ext4_mb_regular_allocator+0x67/0x460 [ 370.818074] [<ffffffff81295b54>] ? ext4_mb_normalize_request+0x1e4/0x5b0 [ 370.818076] [<ffffffff8129ca4b>] ext4_mb_new_blocks+0x4cb/0x620 [ 370.818079] [<ffffffff81290956>] ext4_ext_map_blocks+0x4c6/0x14d0 [ 370.818081] [<ffffffff812a4d4e>] ? ext4_es_lookup_extent+0x4e/0x290 [ 370.818085] [<ffffffff8126399d>] ext4_map_blocks+0x14d/0x4f0 [ 370.818088] [<ffffffff81266fbd>] ext4_writepages+0x76d/0xe50 [ 370.818094] [<ffffffff81149691>] do_writepages+0x21/0x50 [ 370.818097] [<ffffffff811d5c00>] __writeback_single_inode+0x60/0x490 [ 370.818099] [<ffffffff811d630a>] writeback_sb_inodes+0x2da/0x590 [ 370.818103] [<ffffffff811abf4b>] ? trylock_super+0x1b/0x50 [ 370.818105] [<ffffffff811abf4b>] ? trylock_super+0x1b/0x50 [ 370.818107] [<ffffffff811d665f>] __writeback_inodes_wb+0x9f/0xd0 [ 370.818109] [<ffffffff811d69db>] wb_writeback+0x34b/0x3c0 [ 370.818111] [<ffffffff811d70df>] bdi_writeback_workfn+0x23f/0x550 [ 370.818116] [<ffffffff8106bbd8>] process_one_work+0x1c8/0x570 [ 370.818117] [<ffffffff8106bb5b>] ? process_one_work+0x14b/0x570 [ 370.818119] [<ffffffff8106c09b>] worker_thread+0x11b/0x470 [ 370.818121] [<ffffffff8106bf80>] ? process_one_work+0x570/0x570 [ 370.818124] [<ffffffff81071868>] kthread+0xf8/0x110 [ 370.818126] [<ffffffff81071770>] ? kthread_create_on_node+0x210/0x210 [ 370.818129] [<ffffffff819e9322>] ret_from_fork+0x42/0x70 [ 370.818131] [<ffffffff81071770>] ? kthread_create_on_node+0x210/0x210 [ 370.818132] ---[ end trace 7b4deb71e68b6605 ]--- V2: don't change ->in_iowait Cc: NeilBrown <neilb@suse.de> Signed-off-by: Shaohua Li <shli@fb.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* | | watchdog: fix double lock in watchdog_nmi_enable_allMichal Hocko2015-05-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit ab992dc38f9a ("watchdog: Fix merge 'conflict'") has introduced an obvious deadlock because of a typo. watchdog_proc_mutex should be unlocked on exit. Thanks to Miroslav Benes who was staring at the code with me and noticed this. Signed-off-by: Michal Hocko <mhocko@suse.cz> Duh-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>