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2016-09-30sched/debug: Add SCHED_WARN_ON()Peter Zijlstra
Provide SCHED_WARN_ON as wrapper for WARN_ON_ONCE() to avoid CONFIG_SCHED_DEBUG wrappery. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/core: Fix set_user_nice()Peter Zijlstra
Almost all scheduler functions update state with the following pattern: if (queued) dequeue_task(rq, p, DEQUEUE_SAVE); if (running) put_prev_task(rq, p); /* update state */ if (queued) enqueue_task(rq, p, ENQUEUE_RESTORE); if (running) set_curr_task(rq, p); set_user_nice() however misses the running part, cure this. This was found by asserting we never enqueue 'current'. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/fair: Introduce set_curr_task() helperPeter Zijlstra
Now that the ia64 only set_curr_task() symbol is gone, provide a helper just like put_prev_task(). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/core, ia64: Rename set_curr_task()Peter Zijlstra
Rename the ia64 only set_curr_task() function to free up the name. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/core: Fix incorrect utilization accounting when switching to fair classVincent Guittot
When a task switches to fair scheduling class, the period between now and the last update of its utilization is accounted as running time whatever happened during this period. This incorrect accounting applies to the task and also to the task group branch. When changing the property of a running task like its list of allowed CPUs or its scheduling class, we follow the sequence: - dequeue task - put task - change the property - set task as current task - enqueue task The end of the sequence doesn't follow the normal sequence (as per __schedule()) which is: - enqueue a task - then set the task as current task. This incorrectordering is the root cause of incorrect utilization accounting. Update the sequence to follow the right one: - dequeue task - put task - change the property - enqueue task - set task as current task 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: Mike Galbraith <efault@gmx.de> Cc: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bsegall@google.com Cc: dietmar.eggemann@arm.com Cc: linaro-kernel@lists.linaro.org Cc: pjt@google.com Cc: yuyang.du@intel.com Link: http://lkml.kernel.org/r/1473666472-13749-8-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/core: Optimize SCHED_SMTPeter Zijlstra
Avoid pointless SCHED_SMT code when running on !SMT hardware. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/core: Rewrite and improve select_idle_siblings()Peter Zijlstra
select_idle_siblings() is a known pain point for a number of workloads; it either does too much or not enough and sometimes just does plain wrong. This rewrite attempts to address a number of issues (but sadly not all). The current code does an unconditional sched_domain iteration; with the intent of finding an idle core (on SMT hardware). The problems which this patch tries to address are: - its pointless to look for idle cores if the machine is real busy; at which point you're just wasting cycles. - it's behaviour is inconsistent between SMT and !SMT hardware in that !SMT hardware ends up doing a scan for any idle CPU in the LLC domain, while SMT hardware does a scan for idle cores and if that fails, falls back to a scan for idle threads on the 'target' core. The new code replaces the sched_domain scan with 3 explicit scans: 1) search for an idle core in the LLC 2) search for an idle CPU in the LLC 3) search for an idle thread in the 'target' core where 1 and 3 are conditional on SMT support and 1 and 2 have runtime heuristics to skip the step. Step 1) is conditional on sd_llc_shared->has_idle_cores; when a cpu goes idle and sd_llc_shared->has_idle_cores is false, we scan all SMT siblings of the CPU going idle. Similarly, we clear sd_llc_shared->has_idle_cores when we fail to find an idle core. Step 2) tracks the average cost of the scan and compares this to the average idle time guestimate for the CPU doing the wakeup. There is a significant fudge factor involved to deal with the variability of the averages. Esp. hackbench was sensitive to this. Step 3) is unconditional; we assume (also per step 1) that scanning all SMT siblings in a core is 'cheap'. With this; SMT systems gain step 2, which cures a few benchmarks -- notably one from Facebook. One 'feature' of the sched_domain iteration, which we preserve in the new code, is that it would start scanning from the 'target' CPU, instead of scanning the cpumask in cpu id order. This avoids multiple CPUs in the LLC scanning for idle to gang up and find the same CPU quite as much. The down side is that tasks can end up hopping across the LLC for no apparent reason. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30Merge branch 'linus' into locking/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/core: Replace sd_busy/nr_busy_cpus with sched_domain_sharedPeter Zijlstra
Move the nr_busy_cpus thing from its hacky sd->parent->groups->sgc location into the much more natural sched_domain_shared location. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/core: Introduce 'struct sched_domain_shared'Peter Zijlstra
Since struct sched_domain is strictly per cpu; introduce a structure that is shared between all 'identical' sched_domains. Limit to SD_SHARE_PKG_RESOURCES domains for now, as we'll only use it for shared cache state; if another use comes up later we can easily relax this. While the sched_group's are normally shared between CPUs, these are not natural to use when we need some shared state on a domain level -- since that would require the domain to have a parent, which is not a given. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/core: Restructure destroy_sched_domain()Peter Zijlstra
There is no point in doing a call_rcu() for each domain, only do a callback for the root sched domain and clean up the entire set in one go. Also make the entire call chain be called destroy_sched_domain*() to remove confusion with the free_sched_domains() call, which does an entirely different thing. Both cpu_attach_domain() callers of destroy_sched_domain() can live without the call_rcu() because at those points the sched_domain hasn't been published yet. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/core: Remove unused @cpu argument from destroy_sched_domain*()Peter Zijlstra
Small cleanup; nothing uses the @cpu argument so make it go away. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/wait: Introduce init_wait_entry()Oleg Nesterov
The partial initialization of wait_queue_t in prepare_to_wait_event() looks ugly. This was done to shrink .text, but we can simply add the new helper which does the full initialization and shrink the compiled code a bit more. And. This way prepare_to_wait_event() can have more users. In particular we are ready to remove the signal_pending_state() checks from wait_bit_action_f helpers and change __wait_on_bit_lock() to use prepare_to_wait_event(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Neil Brown <neilb@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160906140055.GA6167@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/wait: Avoid abort_exclusive_wait() in __wait_on_bit_lock()Oleg Nesterov
__wait_on_bit_lock() doesn't need abort_exclusive_wait() too. Right now it can't use prepare_to_wait_event() (see the next change), but it can do the additional finish_wait() if action() fails. abort_exclusive_wait() no longer has callers, remove it. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Neil Brown <neilb@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160906140053.GA6164@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/wait: Avoid abort_exclusive_wait() in ___wait_event()Oleg Nesterov
___wait_event() doesn't really need abort_exclusive_wait(), we can simply change prepare_to_wait_event() to remove the waiter from q->task_list if it was interrupted. This simplifies the code/logic, and this way prepare_to_wait_event() can have more users, see the next change. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Neil Brown <neilb@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160908164815.GA18801@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> -- include/linux/wait.h | 7 +------ kernel/sched/wait.c | 35 +++++++++++++++++++++++++---------- 2 files changed, 26 insertions(+), 16 deletions(-)
2016-09-30sched/wait: Fix abort_exclusive_wait(), it should pass TASK_NORMAL to wake_up()Oleg Nesterov
Otherwise this logic only works if mode is "compatible" with another exclusive waiter. If some wq has both TASK_INTERRUPTIBLE and TASK_UNINTERRUPTIBLE waiters, abort_exclusive_wait() won't wait an uninterruptible waiter. The main user is __wait_on_bit_lock() and currently it is fine but only because TASK_KILLABLE includes TASK_UNINTERRUPTIBLE and we do not have lock_page_interruptible() yet. Just use TASK_NORMAL and remove the "mode" arg from abort_exclusive_wait(). Yes, this means that (say) wake_up_interruptible() can wake up the non- interruptible waiter(s), but I think this is fine. And in fact I think that abort_exclusive_wait() must die, see the next change. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Neil Brown <neilb@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160906140047.GA6157@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/fair: Fix fixed point arithmetic width for shares and effective loadDietmar Eggemann
Since commit: 2159197d6677 ("sched/core: Enable increased load resolution on 64-bit kernels") we now have two different fixed point units for load: - 'shares' in calc_cfs_shares() has 20 bit fixed point unit on 64-bit kernels. Therefore use scale_load() on MIN_SHARES. - 'wl' in effective_load() has 10 bit fixed point unit. Therefore use scale_load_down() on tg->shares which has 20 bit fixed point unit on 64-bit kernels. Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1471874441-24701-1-git-send-email-dietmar.eggemann@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/core, x86/topology: Fix NUMA in package topology bugTim Chen
Current code can call set_cpu_sibling_map() and invoke sched_set_topology() more than once (e.g. on CPU hot plug). When this happens after sched_init_smp() has been called, we lose the NUMA topology extension to sched_domain_topology in sched_init_numa(). This results in incorrect topology when the sched domain is rebuilt. This patch fixes the bug and issues warning if we call sched_set_topology() after sched_init_smp(). Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bp@suse.de Cc: jolsa@redhat.com Cc: rjw@rjwysocki.net Link: http://lkml.kernel.org/r/1474485552-141429-2-git-send-email-srinivas.pandruvada@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30Merge branch 'linus' into sched/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30softirq: Let ksoftirqd do its jobEric Dumazet
A while back, Paolo and Hannes sent an RFC patch adding threaded-able napi poll loop support : (https://patchwork.ozlabs.org/patch/620657/) The problem seems to be that softirqs are very aggressive and are often handled by the current process, even if we are under stress and that ksoftirqd was scheduled, so that innocent threads would have more chance to make progress. This patch makes sure that if ksoftirq is running, we let it perform the softirq work. Jonathan Corbet summarized the issue in https://lwn.net/Articles/687617/ Tested: - NIC receiving traffic handled by CPU 0 - UDP receiver running on CPU 0, using a single UDP socket. - Incoming flood of UDP packets targeting the UDP socket. Before the patch, the UDP receiver could almost never get CPU cycles and could only receive ~2,000 packets per second. After the patch, CPU cycles are split 50/50 between user application and ksoftirqd/0, and we can effectively read ~900,000 packets per second, a huge improvement in DOS situation. (Note that more packets are now dropped by the NIC itself, since the BH handlers get less CPU cycles to drain RX ring buffer) Since the load runs in well identified threads context, an admin can more easily tune process scheduling parameters if needed. Reported-by: Paolo Abeni <pabeni@redhat.com> Reported-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: David Miller <davem@davemloft.net> Cc: Hannes Frederic Sowa <hannes@redhat.com> Cc: Jesper Dangaard Brouer <jbrouer@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1472665349.14381.356.camel@edumazet-glaptop3.roam.corp.google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-29cgroup: fix error handling regressions in proc_cgroup_show() and ↵Tejun Heo
cgroup_release_agent() 4c737b41de7f ("cgroup: make cgroup_path() and friends behave in the style of strlcpy()") broke error handling in proc_cgroup_show() and cgroup_release_agent() by not handling negative return values from cgroup_path_ns_locked(). Fix it. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2016-09-29cpuset: fix error handling regression in proc_cpuset_show()Tejun Heo
4c737b41de7f ("cgroup: make cgroup_path() and friends behave in the style of strlcpy()") botched the conversion of proc_cpuset_show() and broke its error handling. It made the function return 0 on failures and fail to handle error returns from cgroup_path_ns(). Fix it. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2016-09-29tracing/syscalls: fix multiline in error message textColin Ian King
pr_info message spans two lines and the literal string is missing a white space between words. Add the white space. Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2016-09-29bpf: allow access into map value arraysJosef Bacik
Suppose you have a map array value that is something like this struct foo { unsigned iter; int array[SOME_CONSTANT]; }; You can easily insert this into an array, but you cannot modify the contents of foo->array[] after the fact. This is because we have no way to verify we won't go off the end of the array at verification time. This patch provides a start for this work. We accomplish this by keeping track of a minimum and maximum value a register could be while we're checking the code. Then at the time we try to do an access into a MAP_VALUE we verify that the maximum offset into that region is a valid access into that memory region. So in practice, code such as this unsigned index = 0; if (foo->iter >= SOME_CONSTANT) foo->iter = index; else index = foo->iter++; foo->array[index] = bar; would be allowed, as we can verify that index will always be between 0 and SOME_CONSTANT-1. If you wish to use signed values you'll have to have an extra check to make sure the index isn't less than 0, or do something like index %= SOME_CONSTANT. Signed-off-by: Josef Bacik <jbacik@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-27bpf: clean up put_cpu_var usageShaohua Li
put_cpu_var takes the percpu data, not the data returned from get_cpu_var. This doesn't change the behavior. Cc: Tejun Heo <tj@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Shaohua Li <shli@fb.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-27compat: remove compat_printk()Arnd Bergmann
After 7e8e385aaf6e ("x86/compat: Remove sys32_vm86_warning"), this function has become unused, so we can remove it as well. Link: http://lkml.kernel.org/r/20160617142903.3070388-1-arnd@arndb.de Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2016-09-27fs: Replace CURRENT_TIME with current_time() for inode timestampsDeepa Dinamani
CURRENT_TIME macro is not appropriate for filesystems as it doesn't use the right granularity for filesystem timestamps. Use current_time() instead. CURRENT_TIME is also not y2038 safe. This is also in preparation for the patch that transitions vfs timestamps to use 64 bit time and hence make them y2038 safe. As part of the effort current_time() will be extended to do range checks. Hence, it is necessary for all file system timestamps to use current_time(). Also, current_time() will be transitioned along with vfs to be y2038 safe. Note that whenever a single call to current_time() is used to change timestamps in different inodes, it is because they share the same time granularity. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Felipe Balbi <balbi@kernel.org> Acked-by: Steven Whitehouse <swhiteho@redhat.com> Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Acked-by: David Sterba <dsterba@suse.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-27Merge branch 'for-4.8-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fixes from Tejun Heo: "Three late fixes for cgroup: Two cpuset ones, one trivial and the other pretty obscure, and a cgroup core fix for a bug which impacts cgroup v2 namespace users" * 'for-4.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: fix invalid controller enable rejections with cgroup namespace cpuset: fix non static symbol warning cpuset: handle race between CPU hotplug and cpuset_hotplug_work
2016-09-27fs/file: more unsigned file descriptorsAlexey Dobriyan
Propagate unsignedness for grand total of 149 bytes: $ ./scripts/bloat-o-meter ../vmlinux-000 ../obj/vmlinux add/remove: 0/0 grow/shrink: 0/10 up/down: 0/-149 (-149) function old new delta set_close_on_exec 99 98 -1 put_files_struct 201 200 -1 get_close_on_exec 59 58 -1 do_prlimit 498 497 -1 do_execveat_common.isra 1662 1661 -1 __close_fd 178 173 -5 do_dup2 219 204 -15 seq_show 685 660 -25 __alloc_fd 384 357 -27 dup_fd 718 646 -72 It mostly comes from converting "unsigned int" to "long" for bit operations. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-27fs: rename "rename2" i_op to "rename"Miklos Szeredi
Generated patch: sed -i "s/\.rename2\t/\.rename\t\t/" `git grep -wl rename2` sed -i "s/\brename2\b/rename/g" `git grep -wl rename2` Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-27libfs: support RENAME_NOREPLACE in simple_rename()Miklos Szeredi
This is trivial to do: - add flags argument to simple_rename() - check if flags doesn't have any other than RENAME_NOREPLACE - assign simple_rename() to .rename2 instead of .rename Filesystems converted: hugetlbfs, ramfs, bpf. Debugfs uses simple_rename() to implement debugfs_rename(), which is for debugfs instances to rename files internally, not for userspace filesystem access. For this case pass zero flags to simple_rename(). Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Alexei Starovoitov <ast@kernel.org>
2016-09-27bpf: Set register type according to is_valid_access()Mickaël Salaün
This prevent future potential pointer leaks when an unprivileged eBPF program will read a pointer value from its context. Even if is_valid_access() returns a pointer type, the eBPF verifier replace it with UNKNOWN_VALUE. The register value that contains a kernel address is then allowed to leak. Moreover, this fix allows unprivileged eBPF programs to use functions with (legitimate) pointer arguments. Not an issue currently since reg_type is only set for PTR_TO_PACKET or PTR_TO_PACKET_END in XDP and TC programs that can only be loaded as privileged. For now, the only unprivileged eBPF program allowed is for socket filtering and all the types from its context are UNKNOWN_VALUE. However, this fix is important for future unprivileged eBPF programs which could use pointers in their context. Signed-off-by: Mickaël Salaün <mic@digikod.net> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-25Merge tag 'trace-v4.8-rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracefs fixes from Steven Rostedt: "Al Viro has been looking at the tracefs code, and has pointed out some issues. This contains one fix by me and one by Al. I'm sure that he'll come up with more but for now I tested these patches and they don't appear to have any negative impact on tracing" * tag 'trace-v4.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: fix memory leaks in tracing_buffers_splice_read() tracing: Move mutex to protect against resetting of seq data
2016-09-25genirq: Make function __irq_do_set_handler() staticWei Yongjun
Fixes the following sparse warning: kernel/irq/chip.c:786:1: warning: symbol '__irq_do_set_handler' was not declared. Should it be static? Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Link: http://lkml.kernel.org/r/1474817799-18676-1-git-send-email-weiyj.lk@gmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-25fix memory leaks in tracing_buffers_splice_read()Al Viro
Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-25tracing: Move mutex to protect against resetting of seq dataSteven Rostedt (Red Hat)
The iter->seq can be reset outside the protection of the mutex. So can reading of user data. Move the mutex up to the beginning of the function. Fixes: d7350c3f45694 ("tracing/core: make the read callbacks reentrants") Cc: stable@vger.kernel.org # 2.6.30+ Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-09-24Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: "Three fixlets for perf: - add a missing NULL pointer check in the intel BTS driver - make BTS an exclusive PMU because BTS can only handle one event at a time - ensure that exclusive events are limited to one PMU so that several exclusive events can be scheduled on different PMU instances" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/core: Limit matching exclusive events to one PMU perf/x86/intel/bts: Make it an exclusive PMU perf/x86/intel/bts: Make sure debug store is valid
2016-09-24Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Thomas Gleixner: "Three fixes for irq core and irq chip drivers: - Do not set the irq type if type is NONE. Fixes a boot regression on various SoCs - Use the proper cpu for setting up the GIC target list. Discovered by the cpumask debugging code. - A rather large fix for the MIPS-GIC so per cpu local interrupts work again. This was discovered late because the code falls back to slower timers which use normal device interrupts" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/mips-gic: Fix local interrupts irqchip/gicv3: Silence noisy DEBUG_PER_CPU_MAPS warning genirq: Skip chained interrupt trigger setup if type is IRQ_TYPE_NONE
2016-09-23cgroup: fix invalid controller enable rejections with cgroup namespaceTejun Heo
On the v2 hierarchy, "cgroup.subtree_control" rejects controller enables if the cgroup has processes in it. The enforcement of this logic assumes that the cgroup wouldn't have any css_sets associated with it if there are no tasks in the cgroup, which is no longer true since a79a908fd2b0 ("cgroup: introduce cgroup namespaces"). When a cgroup namespace is created, it pins the css_set of the creating task to use it as the root css_set of the namespace. This extra reference stays as long as the namespace is around and makes "cgroup.subtree_control" think that the namespace root cgroup is not empty even when it is and thus reject controller enables. Fix it by making cgroup_subtree_control() walk and test emptiness of each css_set instead of testing whether the list_head is empty. While at it, update the comment of cgroup_task_count() to indicate that the returned value may be higher than the number of tasks, which has always been true due to temporary references and doesn't break anything. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Evgeny Vereshchagin <evvers@ya.ru> Cc: Serge E. Hallyn <serge.hallyn@ubuntu.com> Cc: Aditya Kali <adityakali@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: stable@vger.kernel.org # v4.6+ Fixes: a79a908fd2b0 ("cgroup: introduce cgroup namespaces") Link: https://github.com/systemd/systemd/pull/3589#issuecomment-249089541
2016-09-23tracing: Call traceoff trigger after event is recordedMasami Hiramatsu
Call traceoff trigger after the event is recorded. Since current traceoff trigger is called before recording the event, we can not know what event stopped tracing. Typical usecase of traceoff/traceon trigger is tracing function calls and trace events between a pair of events. For example, trace function calls between syscall entry/exit. In that case, it is useful if we can see the return code of the target syscall. Link: http://lkml.kernel.org/r/147335074530.12462.4526186083406015005.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-09-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2016-09-23Merge branch 'perf/urgent' into perf/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22Merge branch 'nsfs-ioctls' into HEADEric W. Biederman
From: Andrey Vagin <avagin@openvz.org> Each namespace has an owning user namespace and now there is not way to discover these relationships. Pid and user namepaces are hierarchical. There is no way to discover parent-child relationships too. Why we may want to know relationships between namespaces? One use would be visualization, in order to understand the running system. Another would be to answer the question: what capability does process X have to perform operations on a resource governed by namespace Y? One more use-case (which usually called abnormal) is checkpoint/restart. In CRIU we are going to dump and restore nested namespaces. There [1] was a discussion about which interface to choose to determing relationships between namespaces. Eric suggested to add two ioctl-s [2]: > Grumble, Grumble. I think this may actually a case for creating ioctls > for these two cases. Now that random nsfs file descriptors are bind > mountable the original reason for using proc files is not as pressing. > > One ioctl for the user namespace that owns a file descriptor. > One ioctl for the parent namespace of a namespace file descriptor. Here is an implementaions of these ioctl-s. $ man man7/namespaces.7 ... Since Linux 4.X, the following ioctl(2) calls are supported for namespace file descriptors. The correct syntax is: fd = ioctl(ns_fd, ioctl_type); where ioctl_type is one of the following: NS_GET_USERNS Returns a file descriptor that refers to an owning user names‐ pace. NS_GET_PARENT Returns a file descriptor that refers to a parent namespace. This ioctl(2) can be used for pid and user namespaces. For user namespaces, NS_GET_PARENT and NS_GET_USERNS have the same meaning. In addition to generic ioctl(2) errors, the following specific ones can occur: EINVAL NS_GET_PARENT was called for a nonhierarchical namespace. EPERM The requested namespace is outside of the current namespace scope. [1] https://lkml.org/lkml/2016/7/6/158 [2] https://lkml.org/lkml/2016/7/9/101 Changes for v2: * don't return ENOENT for init_user_ns and init_pid_ns. There is nothing outside of the init namespace, so we can return EPERM in this case too. > The fewer special cases the easier the code is to get > correct, and the easier it is to read. // Eric Changes for v3: * rename ns->get_owner() to ns->owner(). get_* usually means that it grabs a reference. Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com> Cc: "W. Trevor King" <wking@tremily.us> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Serge Hallyn <serge.hallyn@canonical.com>
2016-09-22nsfs: add ioctl to get a parent namespaceAndrey Vagin
Pid and user namepaces are hierarchical. There is no way to discover parent-child relationships. In a future we will use this interface to dump and restore nested namespaces. Acked-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2016-09-22kernel: add a helper to get an owning user namespace for a namespaceAndrey Vagin
Return -EPERM if an owning user namespace is outside of a process current user namespace. v2: In a first version ns_get_owner returned ENOENT for init_user_ns. This special cases was removed from this version. There is nothing outside of init_user_ns, so we can return EPERM. v3: rename ns->get_owner() to ns->owner(). get_* usually means that it grabs a reference. Acked-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Andrei Vagin <avagin@openvz.org> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2016-09-23kvmconfig: add virtio-gpu to config fragmentRob Herring
virtio-gpu is used for VMs, so add it to the kvm config. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Christoffer Dall <christoffer.dall@linaro.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: kvmarm@lists.cs.columbia.edu Cc: kvm@vger.kernel.org [expanded "frag" to "fragment" in summary] Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-09-23config: move x86 kvm_guest.config to a common locationRob Herring
kvm_guest.config is useful for KVM guests on other arches, and nothing in it appears to be x86 specific, so just move the whole file. Kbuild will find it in either location. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Christoffer Dall <christoffer.dall@linaro.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: kvmarm@lists.cs.columbia.edu Cc: kvm@vger.kernel.org Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-09-22userns: When the per user per user namespace limit is reached return ENOSPCEric W. Biederman
The current error codes returned when a the per user per user namespace limit are hit (EINVAL, EUSERS, and ENFILE) are wrong. I asked for advice on linux-api and it we made clear that those were the wrong error code, but a correct effor code was not suggested. The best general error code I have found for hitting a resource limit is ENOSPC. It is not perfect but as it is unambiguous it will serve until someone comes up with a better error code. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-09-22locking/lglock: Remove lglock implementationPeter Zijlstra
It is now unused, remove it before someone else thinks its a good idea to use this. 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: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22stop_machine: Remove stop_cpus_lock and lg_double_lock/unlock()Oleg Nesterov
stop_two_cpus() and stop_cpus() use stop_cpus_lock to avoid the deadlock, we need to ensure that the stopper functions can't be queued "backwards" from one another. This doesn't look nice; if we use lglock then we do not really need stopper->lock, cpu_stop_queue_work() could use lg_local_lock() under local_irq_save(). OTOH it would be even better to avoid lglock in stop_machine.c and remove lg_double_lock(). This patch adds "bool stop_cpus_in_progress" set/cleared by queue_stop_cpus_work(), and changes cpu_stop_queue_two_works() to busy wait until it is cleared. queue_stop_cpus_work() sets stop_cpus_in_progress = T lockless, but after it queues a work on CPU1 it must be visible to stop_two_cpus(CPU1, CPU2) which checks it under the same lock. And since stop_two_cpus() holds the 2nd lock too, queue_stop_cpus_work() can not clear stop_cpus_in_progress if it is also going to queue a work on CPU2, it needs to take that 2nd lock to do this. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20151121181148.GA433@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>