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2017-08-16sched/completion: Document that reinit_completion() must be called after ↵Steven Rostedt
complete_all() The complete_all() function modifies the completion's "done" variable to UINT_MAX, and no other caller (wait_for_completion(), etc) will modify it back to zero. That means that any call to complete_all() must have a reinit_completion() before that completion can be used again. Document this fact by the complete_all() function. Also document that completion_done() will always return true if complete_all() is called. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170816131202.195c2f4b@gandalf.local.home Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/autogroup: Fix error reporting printk text in autogroup_create()Anshuman Khandual
Its kzalloc() not kmalloc() which has failed earlier. While here remove a redundant empty line. Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20170802084300.29487-1-khandual@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/fair: Fix wake_affine() for !NUMA_BALANCINGPeter Zijlstra
In commit: 3fed382b46ba ("sched/numa: Implement NUMA node level wake_affine()") Rik changed wake_affine to consider NUMA information when balancing between LLC domains. There are a number of problems here which this patch tries to address: - LLC < NODE; in this case we'd use the wrong information to balance - !NUMA_BALANCING: in this case, the new code doesn't do any balancing at all - re-computes the NUMA data for every wakeup, this can mean iterating up to 64 CPUs for every wakeup. - default affine wakeups inside a cache We address these by saving the load/capacity values for each sched_domain during regular load-balance and using these values in wake_affine_llc(). The obvious down-side to using cached values is that they can be too old and poorly reflect reality. But this way we can use LLC wide information and thus not rely on assuming LLC matches NODE. We also don't rely on NUMA_BALANCING nor do we have to aggegate two nodes (or even cache domains) worth of CPUs for each wakeup. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Josef Bacik <josef@toxicpanda.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Fixes: 3fed382b46ba ("sched/numa: Implement NUMA node level wake_affine()") [ Minor readability improvements. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/debug: Intruduce task_state_to_char() helper functionXie XiuQi
Now that we have more than one place to get the task state, intruduce the task_state_to_char() helper function to save some code. No functionality changed. Signed-off-by: Xie XiuQi <xiexiuqi@huawei.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <cj.chengjian@huawei.com> Cc: <huawei.libin@huawei.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/1502095463-160172-3-git-send-email-xiexiuqi@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/debug: Show task state in /proc/sched_debugXie XiuQi
Currently we print the runnable task in /proc/sched_debug, but there is no task state information. We don't know which task is in the runqueue and which task is sleeping. Add task state in the runnable task list, like this: runnable tasks: S task PID tree-key switches prio wait-time sum-exec sum-sleep ----------------------------------------------------------------------------------------------------------- S watchdog/239 1452 -11.917445 2811 0 0.000000 8.949306 0.000000 7 0 / S migration/239 1453 20686.367740 8 0 0.000000 16215.720897 0.000000 7 0 / S ksoftirqd/239 1454 115383.841071 12 120 0.000000 0.200683 0.000000 7 0 / >R test 21287 4872.190970 407 120 0.000000 4874.911790 0.000000 7 0 /autogroup-150 R test 21288 4868.385454 401 120 0.000000 3672.341489 0.000000 7 0 /autogroup-150 R test 21289 4868.326776 384 120 0.000000 3424.934159 0.000000 7 0 /autogroup-150 Signed-off-by: Xie XiuQi <xiexiuqi@huawei.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <cj.chengjian@huawei.com> Cc: <huawei.libin@huawei.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/1502095463-160172-2-git-send-email-xiexiuqi@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/debug: Use task_pid_nr_ns in /proc/$pid/schedAleksa Sarai
It appears as though the addition of the PID namespace did not update the output code for /proc/*/sched, which resulted in it providing PIDs that were not self-consistent with the /proc mount. This additionally made it trivial to detect whether a process was inside &init_pid_ns from userspace, making container detection trivial: https://github.com/jessfraz/amicontained This leads to situations such as: % unshare -pmf % mount -t proc proc /proc % head -n1 /proc/1/sched head (10047, #threads: 1) Fix this by just using task_pid_nr_ns for the output of /proc/*/sched. All of the other uses of task_pid_nr in kernel/sched/debug.c are from a sysctl context and thus don't need to be namespaced. Signed-off-by: Aleksa Sarai <asarai@suse.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Jess Frazelle <acidburn@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: cyphar@cyphar.com Link: http://lkml.kernel.org/r/20170806044141.5093-1-asarai@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/core: Remove unnecessary initialization init_idle_bootup_task()Cheng Jian
init_idle_bootup_task( ) is called in rest_init( ) to switch the scheduling class of the boot thread to the idle class. the function only sets: idle->sched_class = &idle_sched_class; which has been set in init_idle() called by sched_init(): /* * The idle tasks have their own, simple scheduling class: */ idle->sched_class = &idle_sched_class; We've already set the boot thread to idle class in start_kernel()->sched_init()->init_idle() so it's unnecessary to set it again in start_kernel()->rest_init()->init_idle_bootup_task() Signed-off-by: Cheng Jian <cj.chengjian@huawei.com> Signed-off-by: Xie XiuQi <xiexiuqi@huawei.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <akpm@linux-foundation.org> Cc: <huawei.libin@huawei.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/1501838377-109720-1-git-send-email-cj.chengjian@huawei.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/deadline: Change return value of cpudl_find()Byungchul Park
cpudl_find() users are only interested in knowing if suitable CPU(s) were found or not (and then they look at later_mask to know which). Change cpudl_find() return type accordingly. Aligns with rt code. Signed-off-by: Byungchul Park <byungchul.park@lge.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <bristot@redhat.com> Cc: <juri.lelli@gmail.com> Cc: <kernel-team@lge.com> Cc: <rostedt@goodmis.org> 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/1495504859-10960-3-git-send-email-byungchul.park@lge.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/deadline: Make find_later_rq() choose a closer CPU in topologyByungchul Park
When cpudl_find() returns any among free_cpus, the CPU might not be closer than others, considering sched domain. For example: this_cpu: 15 free_cpus: 0, 1,..., 14 (== later_mask) best_cpu: 0 topology: 0 --+ +--+ 1 --+ | +-- ... --+ 2 --+ | | +--+ | 3 --+ | ... ... 12 --+ | +--+ | 13 --+ | | +-- ... -+ 14 --+ | +--+ 15 --+ In this case, it would be best to select 14 since it's a free CPU and closest to 15 (this_cpu). However, currently the code selects 0 (best_cpu) even though that's just any among free_cpus. Fix it. This (re)aligns the deadline behaviour with the rt behaviour. Signed-off-by: Byungchul Park <byungchul.park@lge.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <bristot@redhat.com> Cc: <juri.lelli@gmail.com> Cc: <kernel-team@lge.com> Cc: <rostedt@goodmis.org> 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/1495504859-10960-2-git-send-email-byungchul.park@lge.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/numa: Scale scan period with tasks in group and shared/privateRik van Riel
Running 80 tasks in the same group, or as threads of the same process, results in the memory getting scanned 80x as fast as it would be if a single task was using the memory. This really hurts some workloads. Scale the scan period by the number of tasks in the numa group, and the shared / private ratio, so the average rate at which memory in the group is scanned corresponds roughly to the rate at which a single task would scan its memory. Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: jhladky@redhat.com Cc: lvenanci@redhat.com Link: http://lkml.kernel.org/r/20170731192847.23050-3-riel@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/numa: Slow down scan rate if shared faults dominateRik van Riel
The comment above update_task_scan_period() says the scan period should be increased (scanning slows down) if the majority of memory accesses are on the local node, or if the majority of the page accesses are shared with other tasks. However, with the current code, all a high ratio of shared accesses does is slow down the rate at which scanning is made faster. This patch changes things so either lots of shared accesses or lots of local accesses will slow down scanning, and numa scanning is sped up only when there are lots of private faults on remote memory pages. Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: jhladky@redhat.com Cc: lvenanci@redhat.com Link: http://lkml.kernel.org/r/20170731192847.23050-2-riel@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/pelt: Fix false running accountingVincent Guittot
The running state is a subset of runnable state which means that running can't be set if runnable (weight) is cleared. There are corner cases where the current sched_entity has been already dequeued but cfs_rq->curr has not been updated yet and still points to the dequeued sched_entity. If ___update_load_avg() is called at that time, weight will be 0 and running will be set which is not possible. This case happens during pick_next_task_fair() when a cfs_rq becomes idles. The current sched_entity has been dequeued so se->on_rq is cleared and cfs_rq->weight is null. But cfs_rq->curr still points to se (it will be cleared when picking the idle thread). Because the cfs_rq becomes idle, idle_balance() is called and ends up to call update_blocked_averages() with these wrong running and runnable states. Add a test in ___update_load_avg() to correct the running state in this case. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dietmar.eggemann@arm.com Link: http://lkml.kernel.org/r/1498885573-18984-1-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched: Mark pick_next_task_dl() and build_sched_domain() as staticViresh Kumar
pick_next_task_dl() and build_sched_domain() aren't used outside deadline.c and topology.c. Make them static. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: linaro-kernel@lists.linaro.org Link: http://lkml.kernel.org/r/36e4cbb6210002cadae89920ae97e19e7e513008.1493281605.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/cpupri: Don't re-initialize 'struct cpupri'Viresh Kumar
The 'struct cpupri' passed to cpupri_init() is already initialized to zero. Don't do that again. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: linaro-kernel@lists.linaro.org Link: http://lkml.kernel.org/r/8a71d48c5a077500b6ddc1a41484c0ac8d3aad94.1492065513.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/deadline: Don't re-initialize 'struct cpudl'Viresh Kumar
The 'struct cpudl' passed to cpudl_init() is already initialized to zero. Don't do that again. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: linaro-kernel@lists.linaro.org Link: http://lkml.kernel.org/r/bd4c229806bc96694b15546207afcc221387d2f5.1492065513.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/topology: Drop memset() from init_rootdomain()Viresh Kumar
There are only two callers of init_rootdomain(). One of them passes a global to it and another one sends dynamically allocated root-domain. There is no need to memset the root-domain in the first case as the structure is already reset. Update alloc_rootdomain() to allocate the memory with kzalloc() and remove the memset() call from init_rootdomain(). Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: linaro-kernel@lists.linaro.org Link: http://lkml.kernel.org/r/fc2f6cc90b098040970c85a97046512572d765bc.1492065513.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/fair: Drop always true parameter of update_cfs_rq_load_avg()Viresh Kumar
update_freq is always true and there is no need to pass it to update_cfs_rq_load_avg(). Remove it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: linaro-kernel@lists.linaro.org Link: http://lkml.kernel.org/r/2d28d295f3f591ede7e931462bce1bda5aaa4896.1495603536.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/fair: Avoid checking cfs_rq->nr_running twiceViresh Kumar
Rearrange pick_next_task_fair() a bit to avoid checking cfs_rq->nr_running twice for the case where FAIR_GROUP_SCHED is enabled and the previous task doesn't belong to the fair class. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: linaro-kernel@lists.linaro.org Link: http://lkml.kernel.org/r/000903ab3df3350943d3271c53615893a230dc95.1495603536.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/fair: Pass 'rq' to weighted_cpuload()Viresh Kumar
weighted_cpuload() uses the cpu number passed to it get pointer to the runqueue. Almost all callers of weighted_cpuload() already have the rq pointer with them and can send that directly to weighted_cpuload(). In some cases the callers actually get the CPU number by doing cpu_of(rq). It would be simpler to pass rq to weighted_cpuload(). Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: linaro-kernel@lists.linaro.org Link: http://lkml.kernel.org/r/b7720627e0576dc29b4ba3f9b6edbc913bb4f684.1495603536.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/core: Reuse put_prev_task()Viresh Kumar
Reuse put_prev_task() instead of copying its implementation. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: linaro-kernel@lists.linaro.org Link: http://lkml.kernel.org/r/e2e50578223d05c5e90a9feb964fe1ec5d09a052.1495603536.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10sched/fair: Call cpufreq update util handlers less frequently on UPViresh Kumar
For SMP systems, update_load_avg() calls the cpufreq update util handlers only for the top level cfs_rq (i.e. rq->cfs). But that is not the case for UP systems. update_load_avg() calls util handler for any cfs_rq for which it is called. This would result in way too many calls from the scheduler to the cpufreq governors when CONFIG_FAIR_GROUP_SCHED is enabled. Reduce the frequency of these calls by copying the behavior from the SMP case, i.e. Only call util handlers for the top level cfs_rq. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: linaro-kernel@lists.linaro.org Fixes: 536bd00cdbb7 ("sched/fair: Fix !CONFIG_SMP kernel cpufreq governor breakage") Link: http://lkml.kernel.org/r/6abf69a2107525885b616a2c1ec03d9c0946171c.1495603536.git.viresh.kumar@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-09futex: Remove unnecessary warning from get_futex_keyMel Gorman
Commit 65d8fc777f6d ("futex: Remove requirement for lock_page() in get_futex_key()") removed an unnecessary lock_page() with the side-effect that page->mapping needed to be treated very carefully. Two defensive warnings were added in case any assumption was missed and the first warning assumed a correct application would not alter a mapping backing a futex key. Since merging, it has not triggered for any unexpected case but Mark Rutland reported the following bug triggering due to the first warning. kernel BUG at kernel/futex.c:679! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 3695 Comm: syz-executor1 Not tainted 4.13.0-rc3-00020-g307fec773ba3 #3 Hardware name: linux,dummy-virt (DT) task: ffff80001e271780 task.stack: ffff000010908000 PC is at get_futex_key+0x6a4/0xcf0 kernel/futex.c:679 LR is at get_futex_key+0x6a4/0xcf0 kernel/futex.c:679 pc : [<ffff00000821ac14>] lr : [<ffff00000821ac14>] pstate: 80000145 The fact that it's a bug instead of a warning was due to an unrelated arm64 problem, but the warning itself triggered because the underlying mapping changed. This is an application issue but from a kernel perspective it's a recoverable situation and the warning is unnecessary so this patch removes the warning. The warning may potentially be triggered with the following test program from Mark although it may be necessary to adjust NR_FUTEX_THREADS to be a value smaller than the number of CPUs in the system. #include <linux/futex.h> #include <pthread.h> #include <stdio.h> #include <stdlib.h> #include <sys/mman.h> #include <sys/syscall.h> #include <sys/time.h> #include <unistd.h> #define NR_FUTEX_THREADS 16 pthread_t threads[NR_FUTEX_THREADS]; void *mem; #define MEM_PROT (PROT_READ | PROT_WRITE) #define MEM_SIZE 65536 static int futex_wrapper(int *uaddr, int op, int val, const struct timespec *timeout, int *uaddr2, int val3) { syscall(SYS_futex, uaddr, op, val, timeout, uaddr2, val3); } void *poll_futex(void *unused) { for (;;) { futex_wrapper(mem, FUTEX_CMP_REQUEUE_PI, 1, NULL, mem + 4, 1); } } int main(int argc, char *argv[]) { int i; mem = mmap(NULL, MEM_SIZE, MEM_PROT, MAP_SHARED | MAP_ANONYMOUS, -1, 0); printf("Mapping @ %p\n", mem); printf("Creating futex threads...\n"); for (i = 0; i < NR_FUTEX_THREADS; i++) pthread_create(&threads[i], NULL, poll_futex, NULL); printf("Flipping mapping...\n"); for (;;) { mmap(mem, MEM_SIZE, MEM_PROT, MAP_FIXED | MAP_SHARED | MAP_ANONYMOUS, -1, 0); } return 0; } Reported-and-tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org # 4.7+ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-06Fix compat_sys_sigpending breakageDmitry V. Levin
The latest change of compat_sys_sigpending in commit 8f13621abced ("sigpending(): move compat to native") has broken it in two ways. First, it tries to write 4 bytes more than userspace expects: sizeof(old_sigset_t) == sizeof(long) == 8 instead of sizeof(compat_old_sigset_t) == sizeof(u32) == 4. Second, on big endian architectures these bytes are being written in the wrong order. This bug was found by strace test suite. Reported-by: Anatoly Pugachev <matorola@gmail.com> Inspired-by: Eugene Syromyatnikov <evgsyr@gmail.com> Fixes: 8f13621abced ("sigpending(): move compat to native") Signed-off-by: Dmitry V. Levin <ldv@altlinux.org> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-04Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fix from Thomas Gleixner: "A single fix for a multiplication overflow in the timer code on 32bit systems" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timers: Fix overflow in get_next_timer_interrupt
2017-08-02cpuset: fix a deadlock due to incomplete patching of cpusets_enabled()Dima Zavin
In codepaths that use the begin/retry interface for reading mems_allowed_seq with irqs disabled, there exists a race condition that stalls the patch process after only modifying a subset of the static_branch call sites. This problem manifested itself as a deadlock in the slub allocator, inside get_any_partial. The loop reads mems_allowed_seq value (via read_mems_allowed_begin), performs the defrag operation, and then verifies the consistency of mem_allowed via the read_mems_allowed_retry and the cookie returned by xxx_begin. The issue here is that both begin and retry first check if cpusets are enabled via cpusets_enabled() static branch. This branch can be rewritted dynamically (via cpuset_inc) if a new cpuset is created. The x86 jump label code fully synchronizes across all CPUs for every entry it rewrites. If it rewrites only one of the callsites (specifically the one in read_mems_allowed_retry) and then waits for the smp_call_function(do_sync_core) to complete while a CPU is inside the begin/retry section with IRQs off and the mems_allowed value is changed, we can hang. This is because begin() will always return 0 (since it wasn't patched yet) while retry() will test the 0 against the actual value of the seq counter. The fix is to use two different static keys: one for begin (pre_enable_key) and one for retry (enable_key). In cpuset_inc(), we first bump the pre_enable key to ensure that cpuset_mems_allowed_begin() always return a valid seqcount if are enabling cpusets. Similarly, when disabling cpusets via cpuset_dec(), we first ensure that callers of cpuset_mems_allowed_retry() will start ignoring the seqcount value before we let cpuset_mems_allowed_begin() return 0. The relevant stack traces of the two stuck threads: CPU: 1 PID: 1415 Comm: mkdir Tainted: G L 4.9.36-00104-g540c51286237 #4 Hardware name: Default string Default string/Hardware, BIOS 4.29.1-20170526215256 05/26/2017 task: ffff8817f9c28000 task.stack: ffffc9000ffa4000 RIP: smp_call_function_many+0x1f9/0x260 Call Trace: smp_call_function+0x3b/0x70 on_each_cpu+0x2f/0x90 text_poke_bp+0x87/0xd0 arch_jump_label_transform+0x93/0x100 __jump_label_update+0x77/0x90 jump_label_update+0xaa/0xc0 static_key_slow_inc+0x9e/0xb0 cpuset_css_online+0x70/0x2e0 online_css+0x2c/0xa0 cgroup_apply_control_enable+0x27f/0x3d0 cgroup_mkdir+0x2b7/0x420 kernfs_iop_mkdir+0x5a/0x80 vfs_mkdir+0xf6/0x1a0 SyS_mkdir+0xb7/0xe0 entry_SYSCALL_64_fastpath+0x18/0xad ... CPU: 2 PID: 1 Comm: init Tainted: G L 4.9.36-00104-g540c51286237 #4 Hardware name: Default string Default string/Hardware, BIOS 4.29.1-20170526215256 05/26/2017 task: ffff8818087c0000 task.stack: ffffc90000030000 RIP: int3+0x39/0x70 Call Trace: <#DB> ? ___slab_alloc+0x28b/0x5a0 <EOE> ? copy_process.part.40+0xf7/0x1de0 __slab_alloc.isra.80+0x54/0x90 copy_process.part.40+0xf7/0x1de0 copy_process.part.40+0xf7/0x1de0 kmem_cache_alloc_node+0x8a/0x280 copy_process.part.40+0xf7/0x1de0 _do_fork+0xe7/0x6c0 _raw_spin_unlock_irq+0x2d/0x60 trace_hardirqs_on_caller+0x136/0x1d0 entry_SYSCALL_64_fastpath+0x5/0xad do_syscall_64+0x27/0x350 SyS_clone+0x19/0x20 do_syscall_64+0x60/0x350 entry_SYSCALL64_slow_path+0x25/0x25 Link: http://lkml.kernel.org/r/20170731040113.14197-1-dmitriyz@waymo.com Fixes: 46e700abc44c ("mm, page_alloc: remove unnecessary taking of a seqlock when cpusets are disabled") Signed-off-by: Dima Zavin <dmitriyz@waymo.com> Reported-by: Cliff Spradlin <cspradlin@waymo.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christopher Lameter <cl@linux.com> Cc: Li Zefan <lizefan@huawei.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-02pid: kill pidhash_size in pidhash_init()Kefeng Wang
After commit 3d375d78593c ("mm: update callers to use HASH_ZERO flag"), drop unused pidhash_size in pidhash_init(). Link: http://lkml.kernel.org/r/1500389267-49222-1-git-send-email-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Pavel Tatashin <Pasha.Tatashin@Oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-01timers: Fix overflow in get_next_timer_interruptMatija Glavinic Pecotic
For e.g. HZ=100, timer being 430 jiffies in the future, and 32 bit unsigned int, there is an overflow on unsigned int right-hand side of the expression which results with wrong values being returned. Type cast the multiplier to 64bit to avoid that issue. Fixes: 46c8f0b077a8 ("timers: Fix get_next_timer_interrupt() computation") Signed-off-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Cc: khilman@baylibre.com Cc: akpm@linux-foundation.org Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/a7900f04-2a21-c9fd-67be-ab334d459ee5@nokia.com
2017-07-31Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking fixes from David Miller: 1) Handle notifier registry failures properly in tun/tap driver, from Tonghao Zhang. 2) Fix bpf verifier handling of subtraction bounds and add a testcase for this, from Edward Cree. 3) Increase reset timeout in ftgmac100 driver, from Ben Herrenschmidt. 4) Fix use after free in prd_retire_rx_blk_timer_exired() in AF_PACKET, from Cong Wang. 5) Fix SElinux regression due to recent UDP optimizations, from Paolo Abeni. 6) We accidently increment IPSTATS_MIB_FRAGFAILS in the ipv6 code paths, fix from Stefano Brivio. 7) Fix some mem leaks in dccp, from Xin Long. 8) Adjust MDIO_BUS kconfig deps to avoid build errors, from Arnd Bergmann. 9) Mac address length check and buffer size fixes from Cong Wang. 10) Don't leak sockets in ipv6 udp early demux, from Paolo Abeni. 11) Fix return value when copy_from_user() fails in bpf_prog_get_info_by_fd(), from Daniel Borkmann. 12) Handle PHY_HALTED properly in phy library state machine, from Florian Fainelli. 13) Fix OOPS in fib_sync_down_dev(), from Ido Schimmel. 14) Fix truesize calculation in virtio_net which led to performance regressions, from Michael S Tsirkin. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (76 commits) samples/bpf: fix bpf tunnel cleanup udp6: fix jumbogram reception ppp: Fix a scheduling-while-atomic bug in del_chan Revert "net: bcmgenet: Remove init parameter from bcmgenet_mii_config" virtio_net: fix truesize for mergeable buffers mv643xx_eth: fix of_irq_to_resource() error check MAINTAINERS: Add more files to the PHY LIBRARY section ipv4: fib: Fix NULL pointer deref during fib_sync_down_dev() net: phy: Correctly process PHY_HALTED in phy_stop_machine() sunhme: fix up GREG_STAT and GREG_IMASK register offsets bpf: fix bpf_prog_get_info_by_fd to dump correct xlated_prog_len tcp: avoid bogus gcc-7 array-bounds warning net: tc35815: fix spelling mistake: "Intterrupt" -> "Interrupt" bpf: don't indicate success when copy_from_user fails udp6: fix socket leak on early demux net: thunderx: Fix BGX transmit stall due to underflow Revert "vhost: cache used event for better performance" team: use a larger struct for mac address net: check dev->addr_len for dev_set_mac_address() phy: bcm-ns-usb3: fix MDIO_BUS dependency ...
2017-07-31Merge branch 'for-4.13-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fixes from Tejun Heo: "Several cgroup bug fixes. - cgroup core was calling a migration callback on empty migrations, which could make cpuset crash. - There was a very subtle bug where the controller interface files aren't created directly when cgroup2 is mounted. Because later operations create them, this bug didn't get noticed earlier. - Failed writes to cgroup.subtree_control were incorrectly returning zero" * 'for-4.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: fix error return value from cgroup_subtree_control() cgroup: create dfl_root files on subsys registration cgroup: don't call migration methods if there are no tasks to migrate
2017-07-31Merge branch 'for-4.13-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq Pull workqueue fixes from Tejun Heo: "Two notable fixes. - While adding NUMA affinity support to unbound workqueues, the assumption that an unbound workqueue with max_active == 1 is ordered was broken. The plan was to use explicit alloc_ordered_workqueue() for those cases. Unfortunately, I forgot to update the documentation properly and we grew a handful of use cases which depend on that assumption. While we want to convert them to alloc_ordered_workqueue(), we don't really lose anything by enforcing ordered execution on unbound max_active == 1 workqueues and it doesn't make sense to risk subtle bugs. Restore the assumption. - Workqueue assumes that CPU <-> NUMA node mapping remains static. This is a general assumption - we don't have any synchronization mechanism around CPU <-> node mapping. Unfortunately, powerpc may change the mapping dynamically leading to crashes. Michael added a workaround so that we at least don't crash while powerpc hotplug code gets updated" * 'for-4.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: Work around edge cases for calc of pool's cpumask workqueue: implicit ordered attribute should be overridable workqueue: restore WQ_UNBOUND/max_active==1 to be ordered
2017-07-30Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Thomas Gleixner: "Two patches addressing build warnings caused by inconsistent kernel doc comments" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/wait: Clean up some documentation warnings sched/core: Fix some documentation build warnings
2017-07-29bpf: fix bpf_prog_get_info_by_fd to dump correct xlated_prog_lenDaniel Borkmann
bpf_prog_size(prog->len) is not the correct length we want to dump back to user space. The code in bpf_prog_get_info_by_fd() uses this to copy prog->insnsi to user space, but bpf_prog_size(prog->len) also includes the size of struct bpf_prog itself plus program instructions and is usually used either in context of accounting or for bpf_prog_alloc() et al, thus we copy out of bounds in bpf_prog_get_info_by_fd() potentially. Use the correct bpf_prog_insn_size() instead. Fixes: 1e2709769086 ("bpf: Add BPF_OBJ_GET_INFO_BY_FD") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-29bpf: don't indicate success when copy_from_user failsDaniel Borkmann
err in bpf_prog_get_info_by_fd() still holds 0 at that time from prior check_uarg_tail_zero() check. Explicitly return -EFAULT instead, so user space can be notified of buggy behavior. Fixes: 1e2709769086 ("bpf: Add BPF_OBJ_GET_INFO_BY_FD") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-28workqueue: Work around edge cases for calc of pool's cpumaskMichael Bringmann
There is an underlying assumption/trade-off in many layers of the Linux system that CPU <-> node mapping is static. This is despite the presence of features like NUMA and 'hotplug' that support the dynamic addition/ removal of fundamental system resources like CPUs and memory. PowerPC systems, however, do provide extensive features for the dynamic change of resources available to a system. Currently, there is little or no synchronization protection around the updating of the CPU <-> node mapping, and the export/update of this information for other layers / modules. In systems which can change this mapping during 'hotplug', like PowerPC, the information is changing underneath all layers that might reference it. This patch attempts to ensure that a valid, usable cpumask attribute is used by the workqueue infrastructure when setting up new resource pools. It prevents a crash that has been observed when an 'empty' cpumask is passed along to the worker/task scheduling code. It is intended as a temporary workaround until a more fundamental review and correction of the issue can be done. [With additions to the patch provided by Tejun Hao <tj@kernel.org>] Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2017-07-27genirq/cpuhotplug: Revert "Set force affinity flag on hotplug migration"Thomas Gleixner
That commit was part of the changes moving x86 to the generic CPU hotplug interrupt migration code. The force flag was required on x86 before the hierarchical irqdomain rework, but invoking set_affinity() with force=true stayed and had no side effects. At some point in the past, the force flag got repurposed to support the exynos timer interrupt affinity setting to a not yet online CPU, so the interrupt controller callback does not verify the supplied affinity mask against cpu_online_mask. Setting the flag in the CPU hotplug code causes the cpu online masking to be blocked on these irq controllers and results in potentially affining an interrupt to the CPU which is unplugged, i.e. instead of moving it away, it's just reassigned to it. As the force flags is not longer needed on x86, it's safe to revert that patch so the ARM irqchips which use the force flag work again. Add comments to that effect, so this won't happen again. Note: The online mask handling should be done in the generic code and the force flag and the masking in the irq chips removed all together, but that's not a change possible for 4.13. Fixes: 77f85e66aa8b ("genirq/cpuhotplug: Set force affinity flag on hotplug migration") Reported-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: LAK <linux-arm-kernel@lists.infradead.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1707271217590.3109@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-07-25workqueue: implicit ordered attribute should be overridableTejun Heo
5c0338c68706 ("workqueue: restore WQ_UNBOUND/max_active==1 to be ordered") automatically enabled ordered attribute for unbound workqueues w/ max_active == 1. Because ordered workqueues reject max_active and some attribute changes, this implicit ordered mode broke cases where the user creates an unbound workqueue w/ max_active == 1 and later explicitly changes the related attributes. This patch distinguishes explicit and implicit ordered setting and overrides from attribute changes if implict. Signed-off-by: Tejun Heo <tj@kernel.org> Fixes: 5c0338c68706 ("workqueue: restore WQ_UNBOUND/max_active==1 to be ordered")
2017-07-25sched/core: Fix some documentation build warningsJonathan Corbet
The kerneldoc comments for try_to_wake_up_local() were out of date, leading to these documentation build warnings: ./kernel/sched/core.c:2080: warning: No description found for parameter 'rf' ./kernel/sched/core.c:2080: warning: Excess function parameter 'cookie' description in 'try_to_wake_up_local' Update the comment to reflect current reality and give us some peace and quiet. Signed-off-by: Jonathan Corbet <corbet@lwn.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-doc@vger.kernel.org Link: http://lkml.kernel.org/r/20170724135628.695cecfc@lwn.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-24bpf/verifier: fix min/max handling in BPF_SUBEdward Cree
We have to subtract the src max from the dst min, and vice-versa, since (e.g.) the smallest result comes from the largest subtrahend. Fixes: 484611357c19 ("bpf: allow access into map value arrays") Signed-off-by: Edward Cree <ecree@solarflare.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-23cgroup: fix error return value from cgroup_subtree_control()Tejun Heo
While refactoring, f7b2814bb9b6 ("cgroup: factor out cgroup_{apply|finalize}_control() from cgroup_subtree_control_write()") broke error return value from the function. The return value from the last operation is always overridden to zero. Fix it. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: stable@vger.kernel.org # v4.6+ Signed-off-by: Tejun Heo <tj@kernel.org>
2017-07-21Merge tag 'trace-v4.13-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Three minor updates - Use the new GFP_RETRY_MAYFAIL to be more aggressive in allocating memory for the ring buffer without causing OOMs - Fix a memory leak in adding and removing instances - Add __rcu annotation to be able to debug RCU usage of function tracing a bit better" * tag 'trace-v4.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: trace: fix the errors caused by incompatible type of RCU variables tracing: Fix kmemleak in instance_rmdir tracing/ring_buffer: Try harder to allocate
2017-07-21Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar: "A cputime fix and code comments/organization fix to the deadline scheduler" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/deadline: Fix confusing comments about selection of top pi-waiter sched/cputime: Don't use smp_processor_id() in preemptible context
2017-07-21Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "Two hw-enablement patches, two race fixes, three fixes for regressions of semantics, plus a number of tooling fixes" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/intel: Add proper condition to run sched_task callbacks perf/core: Fix locking for children siblings group read perf/core: Fix scheduling regression of pinned groups perf/x86/intel: Fix debug_store reset field for freq events perf/x86/intel: Add Goldmont Plus CPU PMU support perf/x86/intel: Enable C-state residency events for Apollo Lake perf symbols: Accept zero as the kernel base address Revert "perf/core: Drop kernel samples even though :u is specified" perf annotate: Fix broken arrow at row 0 connecting jmp instruction to its target perf evsel: State in the default event name if attr.exclude_kernel is set perf evsel: Fix attr.exclude_kernel setting for default cycles:p
2017-07-21Merge branch 'locking-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixlet from Ingo Molnar: "Remove an unnecessary priority adjustment in the rtmutex code" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/rtmutex: Remove unnecessary priority adjustment
2017-07-21Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Ingo Molnar: "A resume_irq() fix, plus a number of static declaration fixes" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/digicolor: Drop unnecessary static irqchip/mips-cpu: Drop unnecessary static irqchip/gic/realview: Drop unnecessary static irqchip/mips-gic: Remove population of irq domain names genirq/PM: Properly pretend disabled state when force resuming interrupts
2017-07-21perf/core: Fix locking for children siblings group readJiri Olsa
We're missing ctx lock when iterating children siblings within the perf_read path for group reading. Following race and crash can happen: User space doing read syscall on event group leader: T1: perf_read lock event->ctx->mutex perf_read_group lock leader->child_mutex __perf_read_group_add(child) list_for_each_entry(sub, &leader->sibling_list, group_entry) ----> sub might be invalid at this point, because it could get removed via perf_event_exit_task_context in T2 Child exiting and cleaning up its events: T2: perf_event_exit_task_context lock ctx->mutex list_for_each_entry_safe(child_event, next, &child_ctx->event_list,... perf_event_exit_event(child) lock ctx->lock perf_group_detach(child) unlock ctx->lock ----> child is removed from sibling_list without any sync with T1 path above ... free_event(child) Before the child is removed from the leader's child_list, (and thus is omitted from perf_read_group processing), we need to ensure that perf_read_group touches child's siblings under its ctx->lock. Peter further notes: | One additional note; this bug got exposed by commit: | | ba5213ae6b88 ("perf/core: Correct event creation with PERF_FORMAT_GROUP") | | which made it possible to actually trigger this code-path. Tested-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: ba5213ae6b88 ("perf/core: Correct event creation with PERF_FORMAT_GROUP") Link: http://lkml.kernel.org/r/20170720141455.2106-1-jolsa@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking fixes from David Miller: 1) BPF verifier signed/unsigned value tracking fix, from Daniel Borkmann, Edward Cree, and Josef Bacik. 2) Fix memory allocation length when setting up calls to ->ndo_set_mac_address, from Cong Wang. 3) Add a new cxgb4 device ID, from Ganesh Goudar. 4) Fix FIB refcount handling, we have to set it's initial value before the configure callback (which can bump it). From David Ahern. 5) Fix double-free in qcom/emac driver, from Timur Tabi. 6) A bunch of gcc-7 string format overflow warning fixes from Arnd Bergmann. 7) Fix link level headroom tests in ip_do_fragment(), from Vasily Averin. 8) Fix chunk walking in SCTP when iterating over error and parameter headers. From Alexander Potapenko. 9) TCP BBR congestion control fixes from Neal Cardwell. 10) Fix SKB fragment handling in bcmgenet driver, from Doug Berger. 11) BPF_CGROUP_RUN_PROG_SOCK_OPS needs to check for null __sk, from Cong Wang. 12) xmit_recursion in ppp driver needs to be per-device not per-cpu, from Gao Feng. 13) Cannot release skb->dst in UDP if IP options processing needs it. From Paolo Abeni. 14) Some netdev ioctl ifr_name[] NULL termination fixes. From Alexander Levin and myself. 15) Revert some rtnetlink notification changes that are causing regressions, from David Ahern. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (83 commits) net: bonding: Fix transmit load balancing in balance-alb mode rds: Make sure updates to cp_send_gen can be observed net: ethernet: ti: cpsw: Push the request_irq function to the end of probe ipv4: initialize fib_trie prior to register_netdev_notifier call. rtnetlink: allocate more memory for dev_set_mac_address() net: dsa: b53: Add missing ARL entries for BCM53125 bpf: more tests for mixed signed and unsigned bounds checks bpf: add test for mixed signed and unsigned bounds checks bpf: fix up test cases with mixed signed/unsigned bounds bpf: allow to specify log level and reduce it for test_verifier bpf: fix mixed signed/unsigned derived min/max value bounds ipv6: avoid overflow of offset in ip6_find_1stfragopt net: tehuti: don't process data if it has not been copied from userspace Revert "rtnetlink: Do not generate notifications for CHANGEADDR event" net: dsa: mv88e6xxx: Enable CMODE config support for 6390X dt-binding: ptp: Add SoC compatibility strings for dte ptp clock NET: dwmac: Make dwmac reset unconditional net: Zero terminate ifr_name in dev_ifname(). wireless: wext: terminate ifr name coming from userspace netfilter: fix netfilter_net_init() return ...
2017-07-20bpf: fix mixed signed/unsigned derived min/max value boundsDaniel Borkmann
Edward reported that there's an issue in min/max value bounds tracking when signed and unsigned compares both provide hints on limits when having unknown variables. E.g. a program such as the following should have been rejected: 0: (7a) *(u64 *)(r10 -8) = 0 1: (bf) r2 = r10 2: (07) r2 += -8 3: (18) r1 = 0xffff8a94cda93400 5: (85) call bpf_map_lookup_elem#1 6: (15) if r0 == 0x0 goto pc+7 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R10=fp 7: (7a) *(u64 *)(r10 -16) = -8 8: (79) r1 = *(u64 *)(r10 -16) 9: (b7) r2 = -1 10: (2d) if r1 > r2 goto pc+3 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=0 R2=imm-1,max_value=18446744073709551615,min_align=1 R10=fp 11: (65) if r1 s> 0x1 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=0,max_value=1 R2=imm-1,max_value=18446744073709551615,min_align=1 R10=fp 12: (0f) r0 += r1 13: (72) *(u8 *)(r0 +0) = 0 R0=map_value_adj(ks=8,vs=8,id=0),min_value=0,max_value=1 R1=inv,min_value=0,max_value=1 R2=imm-1,max_value=18446744073709551615,min_align=1 R10=fp 14: (b7) r0 = 0 15: (95) exit What happens is that in the first part ... 8: (79) r1 = *(u64 *)(r10 -16) 9: (b7) r2 = -1 10: (2d) if r1 > r2 goto pc+3 ... r1 carries an unsigned value, and is compared as unsigned against a register carrying an immediate. Verifier deduces in reg_set_min_max() that since the compare is unsigned and operation is greater than (>), that in the fall-through/false case, r1's minimum bound must be 0 and maximum bound must be r2. Latter is larger than the bound and thus max value is reset back to being 'invalid' aka BPF_REGISTER_MAX_RANGE. Thus, r1 state is now 'R1=inv,min_value=0'. The subsequent test ... 11: (65) if r1 s> 0x1 goto pc+2 ... is a signed compare of r1 with immediate value 1. Here, verifier deduces in reg_set_min_max() that since the compare is signed this time and operation is greater than (>), that in the fall-through/false case, we can deduce that r1's maximum bound must be 1, meaning with prior test, we result in r1 having the following state: R1=inv,min_value=0,max_value=1. Given that the actual value this holds is -8, the bounds are wrongly deduced. When this is being added to r0 which holds the map_value(_adj) type, then subsequent store access in above case will go through check_mem_access() which invokes check_map_access_adj(), that will then probe whether the map memory is in bounds based on the min_value and max_value as well as access size since the actual unknown value is min_value <= x <= max_value; commit fce366a9dd0d ("bpf, verifier: fix alu ops against map_value{, _adj} register types") provides some more explanation on the semantics. It's worth to note in this context that in the current code, min_value and max_value tracking are used for two things, i) dynamic map value access via check_map_access_adj() and since commit 06c1c049721a ("bpf: allow helpers access to variable memory") ii) also enforced at check_helper_mem_access() when passing a memory address (pointer to packet, map value, stack) and length pair to a helper and the length in this case is an unknown value defining an access range through min_value/max_value in that case. The min_value/max_value tracking is /not/ used in the direct packet access case to track ranges. However, the issue also affects case ii), for example, the following crafted program based on the same principle must be rejected as well: 0: (b7) r2 = 0 1: (bf) r3 = r10 2: (07) r3 += -512 3: (7a) *(u64 *)(r10 -16) = -8 4: (79) r4 = *(u64 *)(r10 -16) 5: (b7) r6 = -1 6: (2d) if r4 > r6 goto pc+5 R1=ctx R2=imm0,min_value=0,max_value=0,min_align=2147483648 R3=fp-512 R4=inv,min_value=0 R6=imm-1,max_value=18446744073709551615,min_align=1 R10=fp 7: (65) if r4 s> 0x1 goto pc+4 R1=ctx R2=imm0,min_value=0,max_value=0,min_align=2147483648 R3=fp-512 R4=inv,min_value=0,max_value=1 R6=imm-1,max_value=18446744073709551615,min_align=1 R10=fp 8: (07) r4 += 1 9: (b7) r5 = 0 10: (6a) *(u16 *)(r10 -512) = 0 11: (85) call bpf_skb_load_bytes#26 12: (b7) r0 = 0 13: (95) exit Meaning, while we initialize the max_value stack slot that the verifier thinks we access in the [1,2] range, in reality we pass -7 as length which is interpreted as u32 in the helper. Thus, this issue is relevant also for the case of helper ranges. Resetting both bounds in check_reg_overflow() in case only one of them exceeds limits is also not enough as similar test can be created that uses values which are within range, thus also here learned min value in r1 is incorrect when mixed with later signed test to create a range: 0: (7a) *(u64 *)(r10 -8) = 0 1: (bf) r2 = r10 2: (07) r2 += -8 3: (18) r1 = 0xffff880ad081fa00 5: (85) call bpf_map_lookup_elem#1 6: (15) if r0 == 0x0 goto pc+7 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R10=fp 7: (7a) *(u64 *)(r10 -16) = -8 8: (79) r1 = *(u64 *)(r10 -16) 9: (b7) r2 = 2 10: (3d) if r2 >= r1 goto pc+3 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp 11: (65) if r1 s> 0x4 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3,max_value=4 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp 12: (0f) r0 += r1 13: (72) *(u8 *)(r0 +0) = 0 R0=map_value_adj(ks=8,vs=8,id=0),min_value=3,max_value=4 R1=inv,min_value=3,max_value=4 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp 14: (b7) r0 = 0 15: (95) exit This leaves us with two options for fixing this: i) to invalidate all prior learned information once we switch signed context, ii) to track min/max signed and unsigned boundaries separately as done in [0]. (Given latter introduces major changes throughout the whole verifier, it's rather net-next material, thus this patch follows option i), meaning we can derive bounds either from only signed tests or only unsigned tests.) There is still the case of adjust_reg_min_max_vals(), where we adjust bounds on ALU operations, meaning programs like the following where boundaries on the reg get mixed in context later on when bounds are merged on the dst reg must get rejected, too: 0: (7a) *(u64 *)(r10 -8) = 0 1: (bf) r2 = r10 2: (07) r2 += -8 3: (18) r1 = 0xffff89b2bf87ce00 5: (85) call bpf_map_lookup_elem#1 6: (15) if r0 == 0x0 goto pc+6 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R10=fp 7: (7a) *(u64 *)(r10 -16) = -8 8: (79) r1 = *(u64 *)(r10 -16) 9: (b7) r2 = 2 10: (3d) if r2 >= r1 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp 11: (b7) r7 = 1 12: (65) if r7 s> 0x0 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=imm1,max_value=0 R10=fp 13: (b7) r0 = 0 14: (95) exit from 12 to 15: R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=imm1,min_value=1 R10=fp 15: (0f) r7 += r1 16: (65) if r7 s> 0x4 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=inv,min_value=4,max_value=4 R10=fp 17: (0f) r0 += r7 18: (72) *(u8 *)(r0 +0) = 0 R0=map_value_adj(ks=8,vs=8,id=0),min_value=4,max_value=4 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=inv,min_value=4,max_value=4 R10=fp 19: (b7) r0 = 0 20: (95) exit Meaning, in adjust_reg_min_max_vals() we must also reset range values on the dst when src/dst registers have mixed signed/ unsigned derived min/max value bounds with one unbounded value as otherwise they can be added together deducing false boundaries. Once both boundaries are established from either ALU ops or compare operations w/o mixing signed/unsigned insns, then they can safely be added to other regs also having both boundaries established. Adding regs with one unbounded side to a map value where the bounded side has been learned w/o mixing ops is possible, but the resulting map value won't recover from that, meaning such op is considered invalid on the time of actual access. Invalid bounds are set on the dst reg in case i) src reg, or ii) in case dst reg already had them. The only way to recover would be to perform i) ALU ops but only 'add' is allowed on map value types or ii) comparisons, but these are disallowed on pointers in case they span a range. This is fine as only BPF_JEQ and BPF_JNE may be performed on PTR_TO_MAP_VALUE_OR_NULL registers which potentially turn them into PTR_TO_MAP_VALUE type depending on the branch, so only here min/max value cannot be invalidated for them. In terms of state pruning, value_from_signed is considered as well in states_equal() when dealing with adjusted map values. With regards to breaking existing programs, there is a small risk, but use-cases are rather quite narrow where this could occur and mixing compares probably unlikely. Joint work with Josef and Edward. [0] https://lists.iovisor.org/pipermail/iovisor-dev/2017-June/000822.html Fixes: 484611357c19 ("bpf: allow access into map value arrays") Reported-by: Edward Cree <ecree@solarflare.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Edward Cree <ecree@solarflare.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-20Merge branch 'stable-4.13' of git://git.infradead.org/users/pcmoore/auditLinus Torvalds
Pull audit fix from Paul Moore: "A small audit fix, just a single line, to plug a memory leak in some audit error handling code" * 'stable-4.13' of git://git.infradead.org/users/pcmoore/audit: audit: fix memleak in auditd_send_unicast_skb.
2017-07-20trace: fix the errors caused by incompatible type of RCU variablesChunyan Zhang
The variables which are processed by RCU functions should be annotated as RCU, otherwise sparse will report the errors like below: "error: incompatible types in comparison expression (different address spaces)" Link: http://lkml.kernel.org/r/1496823171-7758-1-git-send-email-zhang.chunyan@linaro.org Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org> [ Updated to not be 100% 80 column strict ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-07-20tracing: Fix kmemleak in instance_rmdirChunyu Hu
Hit the kmemleak when executing instance_rmdir, it forgot releasing mem of tracing_cpumask. With this fix, the warn does not appear any more. unreferenced object 0xffff93a8dfaa7c18 (size 8): comm "mkdir", pid 1436, jiffies 4294763622 (age 9134.308s) hex dump (first 8 bytes): ff ff ff ff ff ff ff ff ........ backtrace: [<ffffffff88b6567a>] kmemleak_alloc+0x4a/0xa0 [<ffffffff8861ea41>] __kmalloc_node+0xf1/0x280 [<ffffffff88b505d3>] alloc_cpumask_var_node+0x23/0x30 [<ffffffff88b5060e>] alloc_cpumask_var+0xe/0x10 [<ffffffff88571ab0>] instance_mkdir+0x90/0x240 [<ffffffff886e5100>] tracefs_syscall_mkdir+0x40/0x70 [<ffffffff886565c9>] vfs_mkdir+0x109/0x1b0 [<ffffffff8865b1d0>] SyS_mkdir+0xd0/0x100 [<ffffffff88403857>] do_syscall_64+0x67/0x150 [<ffffffff88b710e7>] return_from_SYSCALL_64+0x0/0x6a [<ffffffffffffffff>] 0xffffffffffffffff Link: http://lkml.kernel.org/r/1500546969-12594-1-git-send-email-chuhu@redhat.com Cc: stable@vger.kernel.org Fixes: ccfe9e42e451 ("tracing: Make tracing_cpumask available for all instances") Signed-off-by: Chunyu Hu <chuhu@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>