- 11 10月, 2016 2 次提交
-
-
由 Emese Revfy 提交于
The __latent_entropy gcc attribute can be used only on functions and variables. If it is on a function then the plugin will instrument it for gathering control-flow entropy. If the attribute is on a variable then the plugin will initialize it with random contents. The variable must be an integer, an integer array type or a structure with integer fields. These specific functions have been selected because they are init functions (to help gather boot-time entropy), are called at unpredictable times, or they have variable loops, each of which provide some level of latent entropy. Signed-off-by: NEmese Revfy <re.emese@gmail.com> [kees: expanded commit message] Signed-off-by: NKees Cook <keescook@chromium.org>
-
由 Emese Revfy 提交于
This adds a new gcc plugin named "latent_entropy". It is designed to extract as much possible uncertainty from a running system at boot time as possible, hoping to capitalize on any possible variation in CPU operation (due to runtime data differences, hardware differences, SMP ordering, thermal timing variation, cache behavior, etc). At the very least, this plugin is a much more comprehensive example for how to manipulate kernel code using the gcc plugin internals. The need for very-early boot entropy tends to be very architecture or system design specific, so this plugin is more suited for those sorts of special cases. The existing kernel RNG already attempts to extract entropy from reliable runtime variation, but this plugin takes the idea to a logical extreme by permuting a global variable based on any variation in code execution (e.g. a different value (and permutation function) is used to permute the global based on loop count, case statement, if/then/else branching, etc). To do this, the plugin starts by inserting a local variable in every marked function. The plugin then adds logic so that the value of this variable is modified by randomly chosen operations (add, xor and rol) and random values (gcc generates separate static values for each location at compile time and also injects the stack pointer at runtime). The resulting value depends on the control flow path (e.g., loops and branches taken). Before the function returns, the plugin mixes this local variable into the latent_entropy global variable. The value of this global variable is added to the kernel entropy pool in do_one_initcall() and _do_fork(), though it does not credit any bytes of entropy to the pool; the contents of the global are just used to mix the pool. Additionally, the plugin can pre-initialize arrays with build-time random contents, so that two different kernel builds running on identical hardware will not have the same starting values. Signed-off-by: NEmese Revfy <re.emese@gmail.com> [kees: expanded commit message and code comments] Signed-off-by: NKees Cook <keescook@chromium.org>
-
- 26 9月, 2016 1 次提交
-
-
由 Al Viro 提交于
Cc: stable@vger.kernel.org Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
-
- 25 9月, 2016 1 次提交
-
-
由 Steven Rostedt (Red Hat) 提交于
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: d7350c3f ("tracing/core: make the read callbacks reentrants") Cc: stable@vger.kernel.org # 2.6.30+ Reported-by: NAl Viro <viro@ZenIV.linux.org.uk> Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
-
- 24 9月, 2016 1 次提交
-
-
由 Tejun Heo 提交于
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 a79a908f ("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: NTejun Heo <tj@kernel.org> Reported-by: NEvgeny 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: a79a908f ("cgroup: introduce cgroup namespaces") Link: https://github.com/systemd/systemd/pull/3589#issuecomment-249089541
-
- 22 9月, 2016 1 次提交
-
-
由 Alexander Shishkin 提交于
An "exclusive" PMU is the one that can only have one event scheduled in at any given time. There may be more than one of such PMUs in a system, though, like Intel PT and BTS. It should be allowed to have one event for either of those inside the same context (there may be other constraints that may prevent this, but those would be hardware-specific). However, the exclusivity code is written so that only one event from any of the "exclusive" PMUs is allowed in a context. Fix this by making the exclusive event filter explicitly match two events' PMUs. Signed-off-by: NAlexander Shishkin <alexander.shishkin@linux.intel.com> Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: vince@deater.net Link: http://lkml.kernel.org/r/20160920154811.3255-3-alexander.shishkin@linux.intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
-
- 20 9月, 2016 1 次提交
-
-
由 Johannes Weiner 提交于
When a socket is cloned, the associated sock_cgroup_data is duplicated but not its reference on the cgroup. As a result, the cgroup reference count will underflow when both sockets are destroyed later on. Fixes: bd1060a1 ("sock, cgroup: add sock->sk_cgroup") Link: http://lkml.kernel.org/r/20160914194846.11153-2-hannes@cmpxchg.orgSigned-off-by: NJohannes Weiner <hannes@cmpxchg.org> Acked-by: NTejun Heo <tj@kernel.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: <stable@vger.kernel.org> [4.5+] Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
- 19 9月, 2016 1 次提交
-
-
由 Marc Zyngier 提交于
There is no point in trying to configure the trigger of a chained interrupt if no trigger information has been configured. At best this is ignored, and at the worse this confuses the underlying irqchip (which is likely not to handle such a thing), and unnecessarily alarms the user. Only apply the configuration if type is not IRQ_TYPE_NONE. Fixes: 1e12c4a9 ("genirq: Correctly configure the trigger on chained interrupts") Reported-and-tested-by: NGeert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com> Link: https://lkml.kernel.org/r/CAMuHMdVW1eTn20=EtYcJ8hkVwohaSuH_yQXrY2MGBEvZ8fpFOg@mail.gmail.com Link: http://lkml.kernel.org/r/1474274967-15984-1-git-send-email-marc.zyngier@arm.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
-
- 16 9月, 2016 1 次提交
-
-
由 Wei Yongjun 提交于
Fixes the following sparse warning: kernel/cpuset.c:2088:6: warning: symbol 'cpuset_fork' was not declared. Should it be static? Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com> Signed-off-by: NTejun Heo <tj@kernel.org>
-
- 13 9月, 2016 1 次提交
-
-
由 Joonwoo Park 提交于
A discrepancy between cpu_online_mask and cpuset's effective_cpus mask is inevitable during hotplug since cpuset defers updating of effective_cpus mask using a workqueue, during which time nothing prevents the system from more hotplug operations. For that reason guarantee_online_cpus() walks up the cpuset hierarchy until it finds an intersection under the assumption that top cpuset's effective_cpus mask intersects with cpu_online_mask even with such a race occurring. However a sequence of CPU hotplugs can open a time window, during which none of the effective CPUs in the top cpuset intersect with cpu_online_mask. For example when there are 4 possible CPUs 0-3 and only CPU0 is online: ======================== =========================== cpu_online_mask top_cpuset.effective_cpus ======================== =========================== echo 1 > cpu2/online. CPU hotplug notifier woke up hotplug work but not yet scheduled. [0,2] [0] echo 0 > cpu0/online. The workqueue is still runnable. [2] [0] ======================== =========================== Now there is no intersection between cpu_online_mask and top_cpuset.effective_cpus. Thus invoking sys_sched_setaffinity() at this moment can cause following: Unable to handle kernel NULL pointer dereference at virtual address 000000d0 ------------[ cut here ]------------ Kernel BUG at ffffffc0001389b0 [verbose debug info unavailable] Internal error: Oops - BUG: 96000005 [#1] PREEMPT SMP Modules linked in: CPU: 2 PID: 1420 Comm: taskset Tainted: G W 4.4.8+ #98 task: ffffffc06a5c4880 ti: ffffffc06e124000 task.ti: ffffffc06e124000 PC is at guarantee_online_cpus+0x2c/0x58 LR is at cpuset_cpus_allowed+0x4c/0x6c <snip> Process taskset (pid: 1420, stack limit = 0xffffffc06e124020) Call trace: [<ffffffc0001389b0>] guarantee_online_cpus+0x2c/0x58 [<ffffffc00013b208>] cpuset_cpus_allowed+0x4c/0x6c [<ffffffc0000d61f0>] sched_setaffinity+0xc0/0x1ac [<ffffffc0000d6374>] SyS_sched_setaffinity+0x98/0xac [<ffffffc000085cb0>] el0_svc_naked+0x24/0x28 The top cpuset's effective_cpus are guaranteed to be identical to cpu_online_mask eventually. Hence fall back to cpu_online_mask when there is no intersection between top cpuset's effective_cpus and cpu_online_mask. Signed-off-by: NJoonwoo Park <joonwoop@codeaurora.org> Acked-by: NLi Zefan <lizefan@huawei.com> Cc: Tejun Heo <tj@kernel.org> Cc: cgroups@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: <stable@vger.kernel.org> # 3.17+ Signed-off-by: NTejun Heo <tj@kernel.org>
-
- 10 9月, 2016 3 次提交
-
-
由 Alexander Shishkin 提交于
The order of accesses to ring buffer's aux_mmap_count and aux_refcount has to be preserved across the users, namely perf_mmap_close() and perf_aux_output_begin(), otherwise the inversion can result in the latter holding the last reference to the aux buffer and subsequently free'ing it in atomic context, triggering a warning. > ------------[ cut here ]------------ > WARNING: CPU: 0 PID: 257 at kernel/events/ring_buffer.c:541 __rb_free_aux+0x11a/0x130 > CPU: 0 PID: 257 Comm: stopbug Not tainted 4.8.0-rc1+ #2596 > Call Trace: > [<ffffffff810f3e0b>] __warn+0xcb/0xf0 > [<ffffffff810f3f3d>] warn_slowpath_null+0x1d/0x20 > [<ffffffff8121182a>] __rb_free_aux+0x11a/0x130 > [<ffffffff812127a8>] rb_free_aux+0x18/0x20 > [<ffffffff81212913>] perf_aux_output_begin+0x163/0x1e0 > [<ffffffff8100c33a>] bts_event_start+0x3a/0xd0 > [<ffffffff8100c42d>] bts_event_add+0x5d/0x80 > [<ffffffff81203646>] event_sched_in.isra.104+0xf6/0x2f0 > [<ffffffff8120652e>] group_sched_in+0x6e/0x190 > [<ffffffff8120694e>] ctx_sched_in+0x2fe/0x5f0 > [<ffffffff81206ca0>] perf_event_sched_in+0x60/0x80 > [<ffffffff81206d1b>] ctx_resched+0x5b/0x90 > [<ffffffff81207281>] __perf_event_enable+0x1e1/0x240 > [<ffffffff81200639>] event_function+0xa9/0x180 > [<ffffffff81202000>] ? perf_cgroup_attach+0x70/0x70 > [<ffffffff8120203f>] remote_function+0x3f/0x50 > [<ffffffff811971f3>] flush_smp_call_function_queue+0x83/0x150 > [<ffffffff81197bd3>] generic_smp_call_function_single_interrupt+0x13/0x60 > [<ffffffff810a6477>] smp_call_function_single_interrupt+0x27/0x40 > [<ffffffff81a26ea9>] call_function_single_interrupt+0x89/0x90 > [<ffffffff81120056>] finish_task_switch+0xa6/0x210 > [<ffffffff81120017>] ? finish_task_switch+0x67/0x210 > [<ffffffff81a1e83d>] __schedule+0x3dd/0xb50 > [<ffffffff81a1efe5>] schedule+0x35/0x80 > [<ffffffff81128031>] sys_sched_yield+0x61/0x70 > [<ffffffff81a25be5>] entry_SYSCALL_64_fastpath+0x18/0xa8 > ---[ end trace 6235f556f5ea83a9 ]--- This patch puts the checks in perf_aux_output_begin() in the same order as that of perf_mmap_close(). Reported-by: NVince Weaver <vincent.weaver@maine.edu> Signed-off-by: NAlexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: vince@deater.net Link: http://lkml.kernel.org/r/20160906132353.19887-3-alexander.shishkin@linux.intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
-
由 Alexander Shishkin 提交于
In the mmap_close() path we need to stop all the AUX events that are writing data to the AUX area that we are unmapping, before we can safely free the pages. To determine if an event needs to be stopped, we're comparing its ->rb against the one that's getting unmapped. However, a SET_OUTPUT ioctl may turn up inside an AUX transaction and swizzle event::rb to some other ring buffer, but the transaction will keep writing data to the old ring buffer until the event gets scheduled out. At this point, mmap_close() will skip over such an event and will proceed to free the AUX area, while it's still being used by this event, which will set off a warning in the mmap_close() path and cause a memory corruption. To avoid this, always stop an AUX event before its ->rb is updated; this will release the (potentially) last reference on the AUX area of the buffer. If the event gets restarted, its new ring buffer will be used. If another SET_OUTPUT comes and switches it back to the old ring buffer that's getting unmapped, it's also fine: this ring buffer's aux_mmap_count will be zero and AUX transactions won't start any more. Reported-by: NVince Weaver <vincent.weaver@maine.edu> Signed-off-by: NAlexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: vince@deater.net Link: http://lkml.kernel.org/r/20160906132353.19887-2-alexander.shishkin@linux.intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
-
由 Dan Williams 提交于
track_pfn_insert() in vmf_insert_pfn_pmd() is marking dax mappings as uncacheable rendering them impractical for application usage. DAX-pte mappings are cached and the goal of establishing DAX-pmd mappings is to attain more performance, not dramatically less (3 orders of magnitude). track_pfn_insert() relies on a previous call to reserve_memtype() to establish the expected page_cache_mode for the range. While memremap() arranges for reserve_memtype() to be called, devm_memremap_pages() does not. So, teach track_pfn_insert() and untrack_pfn() how to handle tracking without a vma, and arrange for devm_memremap_pages() to establish the write-back-cache reservation in the memtype tree. Cc: <stable@vger.kernel.org> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Nilesh Choudhury <nilesh.choudhury@oracle.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: NToshi Kani <toshi.kani@hpe.com> Reported-by: NKai Zhang <kai.ka.zhang@oracle.com> Acked-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NDan Williams <dan.j.williams@intel.com>
-
- 05 9月, 2016 3 次提交
-
-
由 Tejun Heo 提交于
of_clk_init() ends up calling into pm_qos_update_request() very early during boot where irq is expected to stay disabled. pm_qos_update_request() uses cancel_delayed_work_sync() which correctly assumes that irq is enabled on invocation and unconditionally disables and re-enables it. Gate cancel_delayed_work_sync() invocation with kevented_up() to avoid enabling irq unexpectedly during early boot. Signed-off-by: NTejun Heo <tj@kernel.org> Reported-and-tested-by: NQiao Zhou <qiaozhou@asrmicro.com> Link: http://lkml.kernel.org/r/d2501c4c-8e7b-bea3-1b01-000b36b5dfe9@asrmicro.comSigned-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
-
由 Balbir Singh 提交于
The origin of the issue I've seen is related to a missing memory barrier between check for task->state and the check for task->on_rq. The task being woken up is already awake from a schedule() and is doing the following: do { schedule() set_current_state(TASK_(UN)INTERRUPTIBLE); } while (!cond); The waker, actually gets stuck doing the following in try_to_wake_up(): while (p->on_cpu) cpu_relax(); Analysis: The instance I've seen involves the following race: CPU1 CPU2 while () { if (cond) break; do { schedule(); set_current_state(TASK_UN..) } while (!cond); wakeup_routine() spin_lock_irqsave(wait_lock) raw_spin_lock_irqsave(wait_lock) wake_up_process() } try_to_wake_up() set_current_state(TASK_RUNNING); .. list_del(&waiter.list); CPU2 wakes up CPU1, but before it can get the wait_lock and set current state to TASK_RUNNING the following occurs: CPU3 wakeup_routine() raw_spin_lock_irqsave(wait_lock) if (!list_empty) wake_up_process() try_to_wake_up() raw_spin_lock_irqsave(p->pi_lock) .. if (p->on_rq && ttwu_wakeup()) .. while (p->on_cpu) cpu_relax() .. CPU3 tries to wake up the task on CPU1 again since it finds it on the wait_queue, CPU1 is spinning on wait_lock, but immediately after CPU2, CPU3 got it. CPU3 checks the state of p on CPU1, it is TASK_UNINTERRUPTIBLE and the task is spinning on the wait_lock. Interestingly since p->on_rq is checked under pi_lock, I've noticed that try_to_wake_up() finds p->on_rq to be 0. This was the most confusing bit of the analysis, but p->on_rq is changed under runqueue lock, rq_lock, the p->on_rq check is not reliable without this fix IMHO. The race is visible (based on the analysis) only when ttwu_queue() does a remote wakeup via ttwu_queue_remote. In which case the p->on_rq change is not done uder the pi_lock. The result is that after a while the entire system locks up on the raw_spin_irqlock_save(wait_lock) and the holder spins infintely Reproduction of the issue: The issue can be reproduced after a long run on my system with 80 threads and having to tweak available memory to very low and running memory stress-ng mmapfork test. It usually takes a long time to reproduce. I am trying to work on a test case that can reproduce the issue faster, but thats work in progress. I am still testing the changes on my still in a loop and the tests seem OK thus far. Big thanks to Benjamin and Nick for helping debug this as well. Ben helped catch the missing barrier, Nick caught every missing bit in my theory. Signed-off-by: NBalbir Singh <bsingharora@gmail.com> [ Updated comment to clarify matching barriers. Many architectures do not have a full barrier in switch_to() so that cannot be relied upon. ] Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Alexey Kardashevskiy <aik@ozlabs.ru> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nicholas Piggin <nicholas.piggin@gmail.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/e02cce7b-d9ca-1ad0-7a61-ea97c7582b37@gmail.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
-
由 Peter Zijlstra 提交于
This effectively reverts commit: 71e7bc2b ("perf/core: Check return value of the perf_event_read() IPI") ... and puts in a comment explaining why we ignore the return value. Reported-by: NVegard Nossum <vegard.nossum@gmail.com> Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Cc: David Carrillo-Cisneros <davidcc@google.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 71e7bc2b ("perf/core: Check return value of the perf_event_read() IPI") Signed-off-by: NIngo Molnar <mingo@kernel.org>
-
- 02 9月, 2016 6 次提交
-
-
由 Wanpeng Li 提交于
tick_nohz_start_idle() is prevented to be called if the idle tick can't be stopped since commit 1f3b0f82 ("tick/nohz: Optimize nohz idle enter"). As a result, after suspend/resume the host machine, full dynticks kvm guest will softlockup: NMI watchdog: BUG: soft lockup - CPU#0 stuck for 26s! [swapper/0:0] Call Trace: default_idle+0x31/0x1a0 arch_cpu_idle+0xf/0x20 default_idle_call+0x2a/0x50 cpu_startup_entry+0x39b/0x4d0 rest_init+0x138/0x140 ? rest_init+0x5/0x140 start_kernel+0x4c1/0x4ce ? set_init_arg+0x55/0x55 ? early_idt_handler_array+0x120/0x120 x86_64_start_reservations+0x24/0x26 x86_64_start_kernel+0x142/0x14f In addition, cat /proc/stat | grep cpu in guest or host: cpu 398 16 5049 15754 5490 0 1 46 0 0 cpu0 206 5 450 0 0 0 1 14 0 0 cpu1 81 0 3937 3149 1514 0 0 9 0 0 cpu2 45 6 332 6052 2243 0 0 11 0 0 cpu3 65 2 328 6552 1732 0 0 11 0 0 The idle and iowait states are weird 0 for cpu0(housekeeping). The bug is present in both guest and host kernels, and they both have cpu0's idle and iowait states issue, however, host kernel's suspend/resume path etc will touch watchdog to avoid the softlockup. - The watchdog will not be touched in tick_nohz_stop_idle path (need be touched since the scheduler stall is expected) if idle_active flags are not detected. - The idle and iowait states will not be accounted when exit idle loop (resched or interrupt) if idle start time and idle_active flags are not set. This patch fixes it by reverting commit 1f3b0f82 since can't stop idle tick doesn't mean can't be idle. Fixes: 1f3b0f82 ("tick/nohz: Optimize nohz idle enter") Signed-off-by: NWanpeng Li <wanpeng.li@hotmail.com> Cc: Sanjeev Yadav<sanjeev.yadav@spreadtrum.com> Cc: Gaurav Jindal<gaurav.jindal@spreadtrum.com> Cc: stable@vger.kernel.org Cc: kvm@vger.kernel.org Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Link: http://lkml.kernel.org/r/1472798303-4154-1-git-send-email-wanpeng.li@hotmail.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
-
由 Michal Hocko 提交于
Commit fec1d011 ("[PATCH] Disable CLONE_CHILD_CLEARTID for abnormal exit") has caused a subtle regression in nscd which uses CLONE_CHILD_CLEARTID to clear the nscd_certainly_running flag in the shared databases, so that the clients are notified when nscd is restarted. Now, when nscd uses a non-persistent database, clients that have it mapped keep thinking the database is being updated by nscd, when in fact nscd has created a new (anonymous) one (for non-persistent databases it uses an unlinked file as backend). The original proposal for the CLONE_CHILD_CLEARTID change claimed (https://lkml.org/lkml/2006/10/25/233): : The NPTL library uses the CLONE_CHILD_CLEARTID flag on clone() syscalls : on behalf of pthread_create() library calls. This feature is used to : request that the kernel clear the thread-id in user space (at an address : provided in the syscall) when the thread disassociates itself from the : address space, which is done in mm_release(). : : Unfortunately, when a multi-threaded process incurs a core dump (such as : from a SIGSEGV), the core-dumping thread sends SIGKILL signals to all of : the other threads, which then proceed to clear their user-space tids : before synchronizing in exit_mm() with the start of core dumping. This : misrepresents the state of process's address space at the time of the : SIGSEGV and makes it more difficult for someone to debug NPTL and glibc : problems (misleading him/her to conclude that the threads had gone away : before the fault). : : The fix below is to simply avoid the CLONE_CHILD_CLEARTID action if a : core dump has been initiated. The resulting patch from Roland (https://lkml.org/lkml/2006/10/26/269) seems to have a larger scope than the original patch asked for. It seems that limitting the scope of the check to core dumping should work for SIGSEGV issue describe above. [Changelog partly based on Andreas' description] Fixes: fec1d011 ("[PATCH] Disable CLONE_CHILD_CLEARTID for abnormal exit") Link: http://lkml.kernel.org/r/1471968749-26173-1-git-send-email-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com> Tested-by: NWilliam Preston <wpreston@suse.com> Acked-by: NOleg Nesterov <oleg@redhat.com> Cc: Roland McGrath <roland@hack.frob.com> Cc: Andreas Schwab <schwab@suse.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 David Rientjes 提交于
KASAN allocates memory from the page allocator as part of kmem_cache_free(), and that can reference current->mempolicy through any number of allocation functions. It needs to be NULL'd out before the final reference is dropped to prevent a use-after-free bug: BUG: KASAN: use-after-free in alloc_pages_current+0x363/0x370 at addr ffff88010b48102c CPU: 0 PID: 15425 Comm: trinity-c2 Not tainted 4.8.0-rc2+ #140 ... Call Trace: dump_stack kasan_object_err kasan_report_error __asan_report_load2_noabort alloc_pages_current <-- use after free depot_save_stack save_stack kasan_slab_free kmem_cache_free __mpol_put <-- free do_exit This patch sets current->mempolicy to NULL before dropping the final reference. Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1608301442180.63329@chino.kir.corp.google.com Fixes: cd11016e ("mm, kasan: stackdepot implementation. Enable stackdepot for SLAB") Signed-off-by: NDavid Rientjes <rientjes@google.com> Reported-by: NVegard Nossum <vegard.nossum@oracle.com> Acked-by: NAndrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: <stable@vger.kernel.org> [4.6+] Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Sergey Senozhatsky 提交于
__printk_nmi_flush() can be called from nmi_panic(), therefore it has to test whether it's executed in NMI context and thus must route the messages through deferred printk() or via direct printk(). This is to avoid potential deadlocks, as described in commit cf9b1106 ("printk/nmi: flush NMI messages on the system panic"). However there remain two places where __printk_nmi_flush() does unconditional direct printk() calls: - pr_err("printk_nmi_flush: internal error ...") - pr_cont("\n") Factor out print_nmi_seq_line() parts into a new printk_nmi_flush_line() function, which takes care of in_nmi(), and use it in __printk_nmi_flush() for printing and error-reporting. Link: http://lkml.kernel.org/r/20160830161354.581-1-sergey.senozhatsky@gmail.comSigned-off-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Arnd Bergmann 提交于
Using "make tinyconfig" produces a couple of annoying warnings that show up for build test machines all the time: .config:966:warning: override: NOHIGHMEM changes choice state .config:965:warning: override: SLOB changes choice state .config:963:warning: override: KERNEL_XZ changes choice state .config:962:warning: override: CC_OPTIMIZE_FOR_SIZE changes choice state .config:933:warning: override: SLOB changes choice state .config:930:warning: override: CC_OPTIMIZE_FOR_SIZE changes choice state .config:870:warning: override: SLOB changes choice state .config:868:warning: override: KERNEL_XZ changes choice state .config:867:warning: override: CC_OPTIMIZE_FOR_SIZE changes choice state I've made a previous attempt at fixing them and we discussed a number of alternatives. I tried changing the Makefile to use "merge_config.sh -n $(fragment-list)" but couldn't get that to work properly. This is yet another approach, based on the observation that we do want to see a warning for conflicting 'choice' options, and that we can simply make them non-conflicting by listing all other options as disabled. This is a trivial patch that we can apply independent of plans for other changes. Link: http://lkml.kernel.org/r/20160829214952.1334674-2-arnd@arndb.de Link: https://storage.kernelci.org/mainline/v4.7-rc6/x86-tinyconfig/build.log https://patchwork.kernel.org/patch/9212749/Signed-off-by: NArnd Bergmann <arnd@arndb.de> Reviewed-by: NJosh Triplett <josh@joshtriplett.org> Reviewed-by: NMasahiro Yamada <yamada.masahiro@socionext.com> Acked-by: NIngo Molnar <mingo@kernel.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
由 Thiago Jung Bauermann 提交于
If kexec_apply_relocations fails, kexec_load_purgatory frees pi->sechdrs and pi->purgatory_buf. This is redundant, because in case of error kimage_file_prepare_segments calls kimage_file_post_load_cleanup, which will also free those buffers. This causes two warnings like the following, one for pi->sechdrs and the other for pi->purgatory_buf: kexec-bzImage64: Loading purgatory failed ------------[ cut here ]------------ WARNING: CPU: 1 PID: 2119 at mm/vmalloc.c:1490 __vunmap+0xc1/0xd0 Trying to vfree() nonexistent vm area (ffffc90000e91000) Modules linked in: CPU: 1 PID: 2119 Comm: kexec Not tainted 4.8.0-rc3+ #5 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: dump_stack+0x4d/0x65 __warn+0xcb/0xf0 warn_slowpath_fmt+0x4f/0x60 ? find_vmap_area+0x19/0x70 ? kimage_file_post_load_cleanup+0x47/0xb0 __vunmap+0xc1/0xd0 vfree+0x2e/0x70 kimage_file_post_load_cleanup+0x5e/0xb0 SyS_kexec_file_load+0x448/0x680 ? putname+0x54/0x60 ? do_sys_open+0x190/0x1f0 entry_SYSCALL_64_fastpath+0x13/0x8f ---[ end trace 158bb74f5950ca2b ]--- Fix by setting pi->sechdrs an pi->purgatory_buf to NULL, since vfree won't try to free a NULL pointer. Link: http://lkml.kernel.org/r/1472083546-23683-1-git-send-email-bauerman@linux.vnet.ibm.comSigned-off-by: NThiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Acked-by: NBaoquan He <bhe@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
- 01 9月, 2016 2 次提交
-
-
由 Mateusz Guzik 提交于
Prior to the change the function would blindly deference mm, exe_file and exe_file->f_inode, each of which could have been NULL or freed. Use get_task_exe_file to safely obtain stable exe_file. Signed-off-by: NMateusz Guzik <mguzik@redhat.com> Acked-by: NKonstantin Khlebnikov <khlebnikov@yandex-team.ru> Acked-by: NRichard Guy Briggs <rgb@redhat.com> Cc: <stable@vger.kernel.org> # 4.3.x Signed-off-by: NPaul Moore <paul@paul-moore.com>
-
由 Mateusz Guzik 提交于
For more convenient access if one has a pointer to the task. As a minor nit take advantage of the fact that only task lock + rcu are needed to safely grab ->exe_file. This saves mm refcount dance. Use the helper in proc_exe_link. Signed-off-by: NMateusz Guzik <mguzik@redhat.com> Acked-by: NKonstantin Khlebnikov <khlebnikov@yandex-team.ru> Acked-by: NRichard Guy Briggs <rgb@redhat.com> Cc: <stable@vger.kernel.org> # 4.3.x Signed-off-by: NPaul Moore <paul@paul-moore.com>
-
- 31 8月, 2016 1 次提交
-
-
由 Kees Cook 提交于
This fixes a ptrace vs fatal pending signals bug as manifested in seccomp now that seccomp was reordered to happen after ptrace. The short version is that seccomp should not attempt to call do_exit() while fatal signals are pending under a tracer. The existing code was trying to be as defensively paranoid as possible, but it now ends up confusing ptrace. Instead, the syscall can just be skipped (which solves the original concern that the do_exit() was addressing) and normal signal handling, tracer notification, and process death can happen. Paraphrasing from the original bug report: If a tracee task is in a PTRACE_EVENT_SECCOMP trap, or has been resumed after such a trap but not yet been scheduled, and another task in the thread-group calls exit_group(), then the tracee task exits without the ptracer receiving a PTRACE_EVENT_EXIT notification. Test case here: https://gist.github.com/khuey/3c43ac247c72cef8c956ca73281c9be7 The bug happens because when __seccomp_filter() detects fatal_signal_pending(), it calls do_exit() without dequeuing the fatal signal. When do_exit() sends the PTRACE_EVENT_EXIT notification and that task is descheduled, __schedule() notices that there is a fatal signal pending and changes its state from TASK_TRACED to TASK_RUNNING. That prevents the ptracer's waitpid() from returning the ptrace event. A more detailed analysis is here: https://github.com/mozilla/rr/issues/1762#issuecomment-237396255. Reported-by: NRobert O'Callahan <robert@ocallahan.org> Reported-by: NKyle Huey <khuey@kylehuey.com> Tested-by: NKyle Huey <khuey@kylehuey.com> Fixes: 93e35efb ("x86/ptrace: run seccomp after ptrace") Signed-off-by: NKees Cook <keescook@chromium.org> Acked-by: NOleg Nesterov <oleg@redhat.com> Acked-by: NJames Morris <james.l.morris@oracle.com>
-
- 27 8月, 2016 2 次提交
-
-
由 Nicolas Iooss 提交于
Commit bbeddf52 ("printk: move braille console support into separate braille.[ch] files") moved the parsing of braille-related options into _braille_console_setup(), changing the type of variable str from char* to char**. In this commit, memcmp(str, "brl,", 4) was correctly updated to memcmp(*str, "brl,", 4) but not memcmp(str, "brl=", 4). Update the code to make "brl=" option work again and replace memcmp() with strncmp() to make the compiler able to detect such an issue. Fixes: bbeddf52 ("printk: move braille console support into separate braille.[ch] files") Link: http://lkml.kernel.org/r/20160823165700.28952-1-nicolas.iooss_linux@m4x.orgSigned-off-by: NNicolas Iooss <nicolas.iooss_linux@m4x.org> Cc: Joe Perches <joe@perches.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
We have scripts which write to certain fields on 3.18 kernels but this seems to be failing on 4.4 kernels. An entry which we write to here is xfrm_aevent_rseqth which is u32. echo 4294967295 > /proc/sys/net/core/xfrm_aevent_rseqth Commit 230633d1 ("kernel/sysctl.c: detect overflows when converting to int") prevented writing to sysctl entries when integer overflow occurs. However, this does not apply to unsigned integers. Heinrich suggested that we introduce a new option to handle 64 bit limits and set min as 0 and max as UINT_MAX. This might not work as it leads to issues similar to __do_proc_doulongvec_minmax. Alternatively, we would need to change the datatype of the entry to 64 bit. static int __do_proc_doulongvec_minmax(void *data, struct ctl_table { i = (unsigned long *) data; //This cast is causing to read beyond the size of data (u32) vleft = table->maxlen / sizeof(unsigned long); //vleft is 0 because maxlen is sizeof(u32) which is lesser than sizeof(unsigned long) on x86_64. Introduce a new proc handler proc_douintvec. Individual proc entries will need to be updated to use the new handler. [akpm@linux-foundation.org: coding-style fixes] Fixes: 230633d1 ("kernel/sysctl.c:detect overflows when converting to int") Link: http://lkml.kernel.org/r/1471479806-5252-1-git-send-email-subashab@codeaurora.orgSigned-off-by: NSubash Abhinov Kasiviswanathan <subashab@codeaurora.org> Cc: Heinrich Schuchardt <xypron.glpk@gmx.de> Cc: Kees Cook <keescook@chromium.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
-
- 24 8月, 2016 3 次提交
-
-
由 Will Deacon 提交于
When tearing down an AUX buf for an event via perf_mmap_close(), __perf_event_output_stop() is called on the event's CPU to ensure that trace generation is halted before the process of unmapping and freeing the buffer pages begins. The callback is performed via cpu_function_call(), which ensures that it runs with interrupts disabled and is therefore not preemptible. Unfortunately, the current code grabs the per-cpu context pointer using get_cpu_ptr(), which unnecessarily disables preemption and doesn't pair the call with put_cpu_ptr(), leading to a preempt_count() imbalance and a BUG when freeing the AUX buffer later on: WARNING: CPU: 1 PID: 2249 at kernel/events/ring_buffer.c:539 __rb_free_aux+0x10c/0x120 Modules linked in: [...] Call Trace: [<ffffffff813379dd>] dump_stack+0x4f/0x72 [<ffffffff81059ff6>] __warn+0xc6/0xe0 [<ffffffff8105a0c8>] warn_slowpath_null+0x18/0x20 [<ffffffff8112761c>] __rb_free_aux+0x10c/0x120 [<ffffffff81128163>] rb_free_aux+0x13/0x20 [<ffffffff8112515e>] perf_mmap_close+0x29e/0x2f0 [<ffffffff8111da30>] ? perf_iterate_ctx+0xe0/0xe0 [<ffffffff8115f685>] remove_vma+0x25/0x60 [<ffffffff81161796>] exit_mmap+0x106/0x140 [<ffffffff8105725c>] mmput+0x1c/0xd0 [<ffffffff8105cac3>] do_exit+0x253/0xbf0 [<ffffffff8105e32e>] do_group_exit+0x3e/0xb0 [<ffffffff81068d49>] get_signal+0x249/0x640 [<ffffffff8101c273>] do_signal+0x23/0x640 [<ffffffff81905f42>] ? _raw_write_unlock_irq+0x12/0x30 [<ffffffff81905f69>] ? _raw_spin_unlock_irq+0x9/0x10 [<ffffffff81901896>] ? __schedule+0x2c6/0x710 [<ffffffff810022a4>] exit_to_usermode_loop+0x74/0x90 [<ffffffff81002a56>] prepare_exit_to_usermode+0x26/0x30 [<ffffffff81906d1b>] retint_user+0x8/0x10 This patch uses this_cpu_ptr() instead of get_cpu_ptr(), since preemption is already disabled by the caller. Signed-off-by: NWill Deacon <will.deacon@arm.com> Reviewed-by: NAlexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: 95ff4ca2 ("perf/core: Free AUX pages in unmap path") Link: http://lkml.kernel.org/r/20160824091905.GA16944@arm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
-
由 John Stultz 提交于
It was reported that hibernation could fail on the 2nd attempt, where the system hangs at hibernate() -> syscore_resume() -> i8237A_resume() -> claim_dma_lock(), because the lock has already been taken. However there is actually no other process would like to grab this lock on that problematic platform. Further investigation showed that the problem is triggered by setting /sys/power/pm_trace to 1 before the 1st hibernation. Since once pm_trace is enabled, the rtc becomes unmeaningful after suspend, and meanwhile some BIOSes would like to adjust the 'invalid' RTC (e.g, smaller than 1970) to the release date of that motherboard during POST stage, thus after resumed, it may seem that the system had a significant long sleep time which is a completely meaningless value. Then in timekeeping_resume -> tk_debug_account_sleep_time, if the bit31 of the sleep time happened to be set to 1, fls() returns 32 and we add 1 to sleep_time_bin[32], which causes an out of bounds array access and therefor memory being overwritten. As depicted by System.map: 0xffffffff81c9d080 b sleep_time_bin 0xffffffff81c9d100 B dma_spin_lock the dma_spin_lock.val is set to 1, which caused this problem. This patch adds a sanity check in tk_debug_account_sleep_time() to ensure we don't index past the sleep_time_bin array. [jstultz: Problem diagnosed and original patch by Chen Yu, I've solved the issue slightly differently, but borrowed his excelent explanation of the issue here.] Fixes: 5c83545f "power: Add option to log time spent in suspend" Reported-by: NJanek Kozicki <cosurgi@gmail.com> Reported-by: NChen Yu <yu.c.chen@intel.com> Signed-off-by: NJohn Stultz <john.stultz@linaro.org> Cc: linux-pm@vger.kernel.org Cc: Peter Zijlstra <peterz@infradead.org> Cc: Xunlei Pang <xpang@redhat.com> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: stable <stable@vger.kernel.org> Cc: Zhang Rui <rui.zhang@intel.com> Link: http://lkml.kernel.org/r/1471993702-29148-3-git-send-email-john.stultz@linaro.orgSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
-
由 John Stultz 提交于
When I added some extra sanity checking in timekeeping_get_ns() under CONFIG_DEBUG_TIMEKEEPING, I missed that the NMI safe __ktime_get_fast_ns() method was using timekeeping_get_ns(). Thus the locking added to the debug checks broke the NMI-safety of __ktime_get_fast_ns(). This patch open-codes the timekeeping_get_ns() logic for __ktime_get_fast_ns(), so can avoid any deadlocks in NMI. Fixes: 4ca22c26 "timekeeping: Add warnings when overflows or underflows are observed" Reported-by: NSteven Rostedt <rostedt@goodmis.org> Reported-by: NPeter Zijlstra <peterz@infradead.org> Signed-off-by: NJohn Stultz <john.stultz@linaro.org> Cc: stable <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/1471993702-29148-2-git-send-email-john.stultz@linaro.orgSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
-
- 22 8月, 2016 2 次提交
-
-
由 Christoph Hellwig 提交于
Without locking out CPU mask operations we might end up with an inconsistent view of the cpumask in the function. Fixes: 5e385a6e: "genirq: Add a helper to spread an affinity mask for MSI/MSI-X vectors" Signed-off-by: NChristoph Hellwig <hch@lst.de> Link: http://lkml.kernel.org/r/1470924405-25728-1-git-send-email-hch@lst.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
-
由 Shawn Lin 提交于
Obviously we should free action here if irq_chip_pm_get failed. Fixes: be45beb2: "genirq: Add runtime power management support for IRQ chips" Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com> Cc: Jon Hunter <jonathanh@nvidia.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Link: http://lkml.kernel.org/r/1471854112-13006-1-git-send-email-shawn.lin@rock-chips.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
-
- 18 8月, 2016 8 次提交
-
-
由 Wanpeng Li 提交于
Commit: 57430218 ("sched/cputime: Count actually elapsed irq & softirq time") ... fixed a bug but also triggered a regression: On an i5 laptop, 4 pCPUs, 4vCPUs for one full dynticks guest, there are four CPU hog processes(for loop) running in the guest, I hot-unplug the pCPUs on host one by one until there is only one left, then observe CPU utilization via 'top' in the guest, it shows: 100% st for cpu0(housekeeping) 75% st for other CPUs (nohz full mode) However, w/o this commit it shows the correct 75% for all four CPUs. When a guest is interrupted for a longer amount of time, missed clock ticks are not redelivered later. Because of that, we should not limit the amount of steal time accounted to the amount of time that the calling functions think have passed. However, the interval returned by account_other_time() is NOT rounded down to the nearest jiffy, while the base interval in get_vtime_delta() it is subtracted from is, so the max cputime limit is required to avoid underflow. This patch fixes the regression by limiting the account_other_time() from get_vtime_delta() to avoid underflow, and lets the other three call sites (in account_other_time() and steal_account_process_time()) account however much steal time the host told us elapsed. Suggested-by: NRik van Riel <riel@redhat.com> Suggested-by: NPaolo Bonzini <pbonzini@redhat.com> Signed-off-by: NWanpeng Li <wanpeng.li@hotmail.com> Reviewed-by: NRik van Riel <riel@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krcmar <rkrcmar@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kvm@vger.kernel.org Link: http://lkml.kernel.org/r/1471399546-4069-1-git-send-email-wanpeng.li@hotmail.com [ Improved the changelog. ] Signed-off-by: NIngo Molnar <mingo@kernel.org>
-
由 Peter Zijlstra 提交于
Mike reports: Roughly 10% of the time, ltp testcase getrusage04 fails: getrusage04 0 TINFO : Expected timers granularity is 4000 us getrusage04 0 TINFO : Using 1 as multiply factor for max [us]time increment (1000+4000us)! getrusage04 0 TINFO : utime: 0us; stime: 179us getrusage04 0 TINFO : utime: 3751us; stime: 0us getrusage04 1 TFAIL : getrusage04.c:133: stime increased > 5000us: And tracked it down to the case where the task simply doesn't get _any_ [us]time ticks. Update the code to assume all rtime is utime when we lack information, thus ensuring a task that elides the tick gets time accounted. Reported-by: NMike Galbraith <umgwanakikbuti@gmail.com> Tested-by: NMike Galbraith <umgwanakikbuti@gmail.com> Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Fredrik Markstrom <fredrik.markstrom@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim <rkrcmar@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: stable@vger.kernel.org # 4.3+ Fixes: 9d7fb042 ("sched/cputime: Guarantee stime + utime == rtime") Signed-off-by: NIngo Molnar <mingo@kernel.org>
-
由 David Carrillo-Cisneros 提交于
The call to smp_call_function_single in perf_event_read() may fail if an invalid or not online CPU index is passed. Warn user if such bug is present and return error. Signed-off-by: NDavid Carrillo-Cisneros <davidcc@google.com> Signed-off-by: NPeter 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: Kan Liang <kan.liang@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Turner <pjt@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vegard Nossum <vegard.nossum@gmail.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/1471467307-61171-2-git-send-email-davidcc@google.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
-
由 Mathieu Poirier 提交于
At this time the perf_addr_filter_needs_mmap() function will _not_ return true on a user space 'stop' filter. But stop filters need exactly the same kind of mapping that range and start filters get. Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Acked-by: NAlexander 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 <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/1468860187-318-4-git-send-email-mathieu.poirier@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
-
由 Mathieu Poirier 提交于
Function perf_event_mmap() is called by the MM subsystem each time part of a binary is loaded in memory. There can be several mapping for a binary, many times unrelated to the code section. Each time a section of a binary is mapped address filters are updated, event when the map doesn't pertain to the code section. The end result is that filters are configured based on the last map event that was received rather than the last mapping of the code segment. For example if we have an executable 'main' that calls library 'libcstest.so.1.0', and that we want to collect traces on code that is in that library. The perf cmd line for this scenario would be: perf record -e cs_etm// --filter 'filter 0x72c/0x40@/opt/lib/libcstest.so.1.0' --per-thread ./main Resulting in binaries being mapped this way: root@linaro-nano:~# cat /proc/1950/maps 00400000-00401000 r-xp 00000000 08:02 33169 /home/linaro/main 00410000-00411000 r--p 00000000 08:02 33169 /home/linaro/main 00411000-00412000 rw-p 00001000 08:02 33169 /home/linaro/main 7fa2464000-7fa2474000 rw-p 00000000 00:00 0 7fa2474000-7fa25a4000 r-xp 00000000 08:02 543 /lib/aarch64-linux-gnu/libc-2.21.so 7fa25a4000-7fa25b3000 ---p 00130000 08:02 543 /lib/aarch64-linux-gnu/libc-2.21.so 7fa25b3000-7fa25b7000 r--p 0012f000 08:02 543 /lib/aarch64-linux-gnu/libc-2.21.so 7fa25b7000-7fa25b9000 rw-p 00133000 08:02 543 /lib/aarch64-linux-gnu/libc-2.21.so 7fa25b9000-7fa25bd000 rw-p 00000000 00:00 0 7fa25bd000-7fa25be000 r-xp 00000000 08:02 38308 /opt/lib/libcstest.so.1.0 7fa25be000-7fa25cd000 ---p 00001000 08:02 38308 /opt/lib/libcstest.so.1.0 7fa25cd000-7fa25ce000 r--p 00000000 08:02 38308 /opt/lib/libcstest.so.1.0 7fa25ce000-7fa25cf000 rw-p 00001000 08:02 38308 /opt/lib/libcstest.so.1.0 7fa25cf000-7fa25eb000 r-xp 00000000 08:02 574 /lib/aarch64-linux-gnu/ld-2.21.so 7fa25ef000-7fa25f2000 rw-p 00000000 00:00 0 7fa25f7000-7fa25f9000 rw-p 00000000 00:00 0 7fa25f9000-7fa25fa000 r--p 00000000 00:00 0 [vvar] 7fa25fa000-7fa25fb000 r-xp 00000000 00:00 0 [vdso] 7fa25fb000-7fa25fc000 r--p 0001c000 08:02 574 /lib/aarch64-linux-gnu/ld-2.21.so 7fa25fc000-7fa25fe000 rw-p 0001d000 08:02 574 /lib/aarch64-linux-gnu/ld-2.21.so 7ff2ea8000-7ff2ec9000 rw-p 00000000 00:00 0 [stack] root@linaro-nano:~# Before 'main()' can execute 'libcstest.so.1.0' has to be loaded in memory. Once that has been done perf_event_mmap() has been called 4 times, with the last map starting at address 0x7fa25ce000 and the address filter configured to start filtering when the IP has passed over address 0x0x7fa25ce72c (0x7fa25ce000 + 0x72c). But that is wrong since the code segment for library 'libcstest.so.1.0' as been mapped at 0x7fa25bd000, resulting in traces not being collected. This patch corrects the situation by requesting that address filters be updated only if the mapped event is for a code segment. Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Acked-by: NAlexander 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 <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/1468860187-318-3-git-send-email-mathieu.poirier@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
-
由 Mathieu Poirier 提交于
Binary file names have to be supplied for both range and start/stop filters but the current code only processes the filename if an address range filter is specified. This code adds processing of the filename for start/stop filters. Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org> Acked-by: NAlexander 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 <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/1468860187-318-2-git-send-email-mathieu.poirier@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>
-
由 Peter Zijlstra 提交于
Vincent reported triggering the WARN_ON_ONCE() in event_function_local(). While thinking through cases I noticed that by using event_function() directly, we miss the inactive case usually handled by event_function_call(). Therefore construct a blend of event_function_call() and event_function() that handles the cases relevant to event_function_local(). Reported-by: NVince Weaver <vincent.weaver@maine.edu> Signed-off-by: NPeter 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 <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org # 4.5+ Fixes: fae3fde6 ("perf: Collapse and fix event_function_call() users") Signed-off-by: NIngo Molnar <mingo@kernel.org>
-
由 Oleg Nesterov 提交于
__replace_page() wronlgy calls mem_cgroup_cancel_charge() in "success" path, it should only do this if page_check_address() fails. This means that every enable/disable leads to unbalanced mem_cgroup_uncharge() from put_page(old_page), it is trivial to underflow the page_counter->count and trigger OOM. Reported-and-tested-by: NBrenden Blanco <bblanco@plumgrid.com> Signed-off-by: NOleg Nesterov <oleg@redhat.com> Reviewed-by: NJohannes Weiner <hannes@cmpxchg.org> Acked-by: NMichal Hocko <mhocko@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Cc: stable@vger.kernel.org # 3.17+ Fixes: 00501b53 ("mm: memcontrol: rewrite charge API") Link: http://lkml.kernel.org/r/20160817153629.GB29724@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
-