aboutsummaryrefslogtreecommitdiff
path: root/kernel
AgeCommit message (Collapse)AuthorFilesLines
2017-02-20Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds12-206/+313
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU updates from Ingo Molnar: "The RCU changes in this cycle are: - Dynticks updates, consolidating open-coded counter accesses into a well-defined API - SRCU updates: Simplify algorithm, add formal verification - Documentation updates - Miscellaneous fixes - Torture-test updates Most of the diffstat comes from the relatively large documentation update" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (42 commits) srcu: Reduce probability of SRCU ->unlock_count[] counter overflow rcutorture: Add CBMC-based formal verification for SRCU srcu: Force full grace-period ordering srcu: Implement more-efficient reader counts rcu: Adjust FQS offline checks for exact online-CPU detection rcu: Check cond_resched_rcu_qs() state less often to reduce GP overhead rcu: Abstract extended quiescent state determination rcu: Abstract dynticks extended quiescent state enter/exit operations rcu: Add lockdep checks to synchronous expedited primitives rcu: Eliminate unused expedited_normal counter llist: Clarify comments about when locking is needed rcu: Fix comment in rcu_organize_nocb_kthreads() rcu: Enable RCU tracepoints by default to aid in debugging rcu: Make rcu_cpu_starting() use its "cpu" argument rcu: Add comment headers to expedited-grace-period counter functions rcu: Don't wake rcuc/X kthreads on NOCB CPUs rcu: Re-enable TASKS_RCU for User Mode Linux rcu: Once again use NMI-based stack traces in stall warnings rcu: Remove short-term CPU kicking rcu: Add long-term CPU kicking ...
2017-02-20Merge branch 'irq-core-for-linus' of ↵Linus Torvalds3-3/+68
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq updates from Thomas Gleixner: "This update provides: - Yet another two irq controller chip drivers - A few updates and fixes for GICV3 - A resource managed function for interrupt allocation - Fixes, updates and enhancements all over the place" * 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/qcom: Fix error handling genirq: Clarify logic calculating bogus irqreturn_t values genirq/msi: Add stubs for get_cached_msi_msg/pci_write_msi_msg genirq/devres: Use dev_name(dev) as default for devname genirq: Fix /proc/interrupts output alignment irqdesc: Add a resource managed version of irq_alloc_descs() irqchip/gic-v3-its: Zero command on allocation irqchip/gic-v3-its: Fix command buffer allocation irqchip/mips-gic: Fix local interrupts irqchip: Add a driver for Cortina Gemini irqchip: DT bindings for Cortina Gemini irqchip irqchip/gic-v3: Remove duplicate definition of GICD_TYPER_LPIS irqchip/gic-v3-its: Rename MAPVI to MAPTI irqchip/gic-v3-its: Drop deprecated GITS_BASER_TYPE_CPU irqchip/gic-v3-its: Refactor command encoding irqchip/gic-v3-its: Enable cacheable attribute Read-allocate hints irqchip/qcom: Add IRQ combiner driver ACPI: Add support for ResourceSource/IRQ domain mapping ACPI: Generic GSI: Do not attempt to map non-GSI IRQs during bus scan irq/platform-msi: Fix comment about maximal MSIs
2017-02-20Merge branch 'timers-core-for-linus' of ↵Linus Torvalds13-589/+60
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "Nothing exciting, just the usual pile of fixes, updates and cleanups: - A bunch of clocksource driver updates - Removal of CONFIG_TIMER_STATS and the related /proc file - More posix timer slim down work - A scalability enhancement in the tick broadcast code - Math cleanups" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) hrtimer: Catch invalid clockids again math64, tile: Fix build failure clocksource/drivers/arm_arch_timer:: Mark cyclecounter __ro_after_init timerfd: Protect the might cancel mechanism proper timer_list: Remove useless cast when printing time: Remove CONFIG_TIMER_STATS clocksource/drivers/arm_arch_timer: Work around Hisilicon erratum 161010101 clocksource/drivers/arm_arch_timer: Introduce generic errata handling infrastructure clocksource/drivers/arm_arch_timer: Remove fsl-a008585 parameter clocksource/drivers/arm_arch_timer: Add dt binding for hisilicon-161010101 erratum clocksource/drivers/ostm: Add renesas-ostm timer driver clocksource/drivers/ostm: Document renesas-ostm timer DT bindings clocksource/drivers/tcb_clksrc: Use 32 bit tcb as sched_clock clocksource/drivers/gemini: Add driver for the Cortina Gemini clocksource: add DT bindings for Cortina Gemini clockevents: Add a clkevt-of mechanism like clksrc-of tick/broadcast: Reduce lock cacheline contention timers: Omit POSIX timer stuff from task_struct when disabled x86/timer: Make delay() work during early bootup delay: Add explanation of udelay() inaccuracy ...
2017-02-20Merge branch 'pm-sleep'Rafael J. Wysocki2-2/+2
* pm-sleep: PM / Documentation: Spelling s/wrtie/write/ PM / sleep: Fix test_suspend after sleep state rework PM / Hibernate: Use rb_entry() instead of container_of()
2017-02-20fork: Fix task_struct alignmentPeter Zijlstra1-1/+1
Stupid bug that wrecked the alignment of task_struct and causes WARN()s in the x86 FPU code on some platforms. Reported-by: Fengguang Wu <[email protected]> Tested-by: Fengguang Wu <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Fixes: e274795ea7b7 ("locking/mutex: Fix mutex handoff") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2017-02-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller6-26/+13
2017-02-18Merge branch 'locking-urgent-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fix from Thomas Gleixner: "Move the futex init function to core initcall so user mode helper does not run into an uninitialized futex syscall" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: futex: Move futex_init() to core_initcall
2017-02-18Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2-10/+9
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Thomas Gleixner: "Two small fixes:: - Prevent deadlock on the tick broadcast lock. Found and fixed by Mike. - Stop using printk() in the timekeeping debug code to prevent a deadlock against the scheduler" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timekeeping: Use deferred printk() in debug code tick/broadcast: Prevent deadlock on tick_broadcast_lock
2017-02-18printk: use rcuidle console tracepointSergey Senozhatsky1-1/+1
Use rcuidle console tracepoint because, apparently, it may be issued from an idle CPU: hw-breakpoint: Failed to enable monitor mode on CPU 0. hw-breakpoint: CPU 0 failed to disable vector catch =============================== [ ERR: suspicious RCU usage. ] 4.10.0-rc8-next-20170215+ #119 Not tainted ------------------------------- ./include/trace/events/printk.h:32 suspicious rcu_dereference_check() usage! other info that might help us debug this: RCU used illegally from idle CPU! rcu_scheduler_active = 2, debug_locks = 0 RCU used illegally from extended quiescent state! 2 locks held by swapper/0/0: #0: (cpu_pm_notifier_lock){......}, at: [<c0237e2c>] cpu_pm_exit+0x10/0x54 #1: (console_lock){+.+.+.}, at: [<c01ab350>] vprintk_emit+0x264/0x474 stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.10.0-rc8-next-20170215+ #119 Hardware name: Generic OMAP4 (Flattened Device Tree) console_unlock vprintk_emit vprintk_default printk reset_ctrl_regs dbg_cpu_pm_notify notifier_call_chain cpu_pm_exit omap_enter_idle_coupled cpuidle_enter_state cpuidle_enter_state_coupled do_idle cpu_startup_entry start_kernel This RCU warning, however, is suppressed by lockdep_off() in printk(). lockdep_off() increments the ->lockdep_recursion counter and thus disables RCU_LOCKDEP_WARN() and debug_lockdep_rcu_enabled(), which want lockdep to be enabled "current->lockdep_recursion == 0". Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Sergey Senozhatsky <[email protected]> Reported-by: Tony Lindgren <[email protected]> Tested-by: Tony Lindgren <[email protected]> Acked-by: Paul E. McKenney <[email protected]> Acked-by: Steven Rostedt (VMware) <[email protected]> Cc: Petr Mladek <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Tony Lindgren <[email protected]> Cc: Russell King <[email protected]> Cc: <[email protected]> [3.4+] Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
2017-02-18hrtimer: Catch invalid clockids againMarc Zyngier1-5/+15
commit 82e88ff1ea94 ("hrtimer: Revert CLOCK_MONOTONIC_RAW support") removed unfortunately a sanity check in the hrtimer code which was part of that MONOTONIC_RAW patch series. It would have caught the bogus usage of CLOCK_MONOTONIC_RAW in the wireless code. So bring it back. It is way too easy to take any random clockid and feed it to the hrtimer subsystem. At best, it gets mapped to a monotonic base, but it would be better to just catch illegal values as early as possible. Detect invalid clockids, map them to CLOCK_MONOTONIC and emit a warning. [ tglx: Replaced the BUG by a WARN and gracefully map to CLOCK_MONOTONIC ] Signed-off-by: Marc Zyngier <[email protected]> Cc: Tomasz Nowicki <[email protected]> Cc: Christoffer Dall <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
2017-02-18PM / sleep: Fix test_suspend after sleep state reworkGeert Uytterhoeven1-1/+1
When passing "test_suspend=mem" to the kernel: PM: can't test 'mem' suspend state and the suspend test is not run. Commit 406e79385f3223d8 ("PM / sleep: System sleep state selection interface rework") changed pm_labels[] from a contiguous NULL-terminated array to a sparse array (with the first element unpopulated), breaking the assumptions of the iterator in setup_test_suspend(). Iterate from PM_SUSPEND_MIN to PM_SUSPEND_MAX - 1 to fix this. Fixes: 406e79385f3223d8 (PM / sleep: System sleep state selection interface rework) Signed-off-by: Geert Uytterhoeven <[email protected]> Signed-off-by: Rafael J. Wysocki <[email protected]>
2017-02-17Merge branch 'for-4.11/next' into for-4.11/linus-mergeJens Axboe1-57/+21
Signed-off-by: Jens Axboe <[email protected]>
2017-02-17bpf: make jited programs visible in tracesDaniel Borkmann4-13/+282
Long standing issue with JITed programs is that stack traces from function tracing check whether a given address is kernel code through {__,}kernel_text_address(), which checks for code in core kernel, modules and dynamically allocated ftrace trampolines. But what is still missing is BPF JITed programs (interpreted programs are not an issue as __bpf_prog_run() will be attributed to them), thus when a stack trace is triggered, the code walking the stack won't see any of the JITed ones. The same for address correlation done from user space via reading /proc/kallsyms. This is read by tools like perf, but the latter is also useful for permanent live tracing with eBPF itself in combination with stack maps when other eBPF types are part of the callchain. See offwaketime example on dumping stack from a map. This work tries to tackle that issue by making the addresses and symbols known to the kernel. The lookup from *kernel_text_address() is implemented through a latched RB tree that can be read under RCU in fast-path that is also shared for symbol/size/offset lookup for a specific given address in kallsyms. The slow-path iteration through all symbols in the seq file done via RCU list, which holds a tiny fraction of all exported ksyms, usually below 0.1 percent. Function symbols are exported as bpf_prog_<tag>, in order to aide debugging and attribution. This facility is currently enabled for root-only when bpf_jit_kallsyms is set to 1, and disabled if hardening is active in any mode. The rationale behind this is that still a lot of systems ship with world read permissions on kallsyms thus addresses should not get suddenly exposed for them. If that situation gets much better in future, we always have the option to change the default on this. Likewise, unprivileged programs are not allowed to add entries there either, but that is less of a concern as most such programs types relevant in this context are for root-only anyway. If enabled, call graphs and stack traces will then show a correct attribution; one example is illustrated below, where the trace is now visible in tooling such as perf script --kallsyms=/proc/kallsyms and friends. Before: 7fff8166889d bpf_clone_redirect+0x80007f0020ed (/lib/modules/4.9.0-rc8+/build/vmlinux) f5d80 __sendmsg_nocancel+0xffff006451f1a007 (/usr/lib64/libc-2.18.so) After: 7fff816688b7 bpf_clone_redirect+0x80007f002107 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fffa0575728 bpf_prog_33c45a467c9e061a+0x8000600020fb (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fffa07ef1fc cls_bpf_classify+0x8000600020dc (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff81678b68 tc_classify+0x80007f002078 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff8164d40b __netif_receive_skb_core+0x80007f0025fb (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff8164d718 __netif_receive_skb+0x80007f002018 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff8164e565 process_backlog+0x80007f002095 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff8164dc71 net_rx_action+0x80007f002231 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff81767461 __softirqentry_text_start+0x80007f0020d1 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff817658ac do_softirq_own_stack+0x80007f00201c (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff810a2c20 do_softirq+0x80007f002050 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff810a2cb5 __local_bh_enable_ip+0x80007f002085 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff8168d452 ip_finish_output2+0x80007f002152 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff8168ea3d ip_finish_output+0x80007f00217d (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff8168f2af ip_output+0x80007f00203f (/lib/modules/4.9.0-rc8+/build/vmlinux) [...] 7fff81005854 do_syscall_64+0x80007f002054 (/lib/modules/4.9.0-rc8+/build/vmlinux) 7fff817649eb return_from_SYSCALL_64+0x80007f002000 (/lib/modules/4.9.0-rc8+/build/vmlinux) f5d80 __sendmsg_nocancel+0xffff01c484812007 (/usr/lib64/libc-2.18.so) Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Cc: [email protected] Signed-off-by: David S. Miller <[email protected]>
2017-02-17bpf: remove stubs for cBPF from arch codeDaniel Borkmann1-1/+11
Remove the dummy bpf_jit_compile() stubs for eBPF JITs and make that a single __weak function in the core that can be overridden similarly to the eBPF one. Also remove stale pr_err() mentions of bpf_jit_compile. Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Signed-off-by: David S. Miller <[email protected]>
2017-02-17bpf: mark all registered map/prog types as __ro_after_initDaniel Borkmann5-14/+14
All map types and prog types are registered to the BPF core through bpf_register_map_type() and bpf_register_prog_type() during init and remain unchanged thereafter. As by design we don't (and never will) have any pluggable code that can register to that at any later point in time, lets mark all the existing bpf_{map,prog}_type_list objects in the tree as __ro_after_init, so they can be moved to read-only section from then onwards. Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Signed-off-by: David S. Miller <[email protected]>
2017-02-17tracing: Remove outdated ring buffer commentJoel Fernandes1-10/+2
The comment about ring buffer's organization is outdated and the code sits elsewhere, remove the comment. Link: http://lkml.kernel.org/r/[email protected] Cc: Ingo Molnar <[email protected]> Signed-off-by: Joel Fernandes <[email protected]> Signed-off-by: Steven Rostedt (VMware) <[email protected]>
2017-02-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller6-40/+90
2017-02-16Revert "nohz: Fix collision between tick and other hrtimers"Linus Torvalds2-14/+2
This reverts commit 24b91e360ef521a2808771633d76ebc68bd5604b and commit 7bdb59f1ad47 ("tick/nohz: Fix possible missing clock reprog after tick soft restart") that depends on it, Pavel reports that it causes occasional boot hangs for him that seem to depend on just how the machine was booted. In particular, his machine hangs at around the PCI fixups of the EHCI USB host controller, but only hangs from cold boot, not from a warm boot. Thomas Gleixner suspecs it's a CPU hotplug interaction, particularly since Pavel also saw suspend/resume issues that seem to be related. We're reverting for now while trying to figure out the root cause. Reported-bisected-and-tested-by: Pavel Machek <[email protected]> Acked-by: Frederic Weisbecker <[email protected]> Cc: Wanpeng Li <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] # reverted commits were marked for stable Signed-off-by: Linus Torvalds <[email protected]>
2017-02-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds3-22/+66
Pull networking fixes from David Miller: 1) In order to avoid problems in the future, make cgroup bpf overriding explicit using BPF_F_ALLOW_OVERRIDE. From Alexei Staovoitov. 2) LLC sets skb->sk without proper skb->destructor and this explodes, fix from Eric Dumazet. 3) Make sure when we have an ipv4 mapped source address, the destination is either also an ipv4 mapped address or ipv6_addr_any(). Fix from Jonathan T. Leighton. 4) Avoid packet loss in fec driver by programming the multicast filter more intelligently. From Rui Sousa. 5) Handle multiple threads invoking fanout_add(), fix from Eric Dumazet. 6) Since we can invoke the TCP input path in process context, without BH being disabled, we have to accomodate that in the locking of the TCP probe. Also from Eric Dumazet. 7) Fix erroneous emission of NETEVENT_DELAY_PROBE_TIME_UPDATE when we aren't even updating that sysctl value. From Marcus Huewe. 8) Fix endian bugs in ibmvnic driver, from Thomas Falcon. [ This is the second version of the pull that reverts the nested rhashtable changes that looked a bit too scary for this late in the release - Linus ] * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (27 commits) rhashtable: Revert nested table changes. ibmvnic: Fix endian errors in error reporting output ibmvnic: Fix endian error when requesting device capabilities net: neigh: Fix netevent NETEVENT_DELAY_PROBE_TIME_UPDATE notification net: xilinx_emaclite: fix freezes due to unordered I/O net: xilinx_emaclite: fix receive buffer overflow bpf: kernel header files need to be copied into the tools directory tcp: tcp_probe: use spin_lock_bh() uapi: fix linux/if_pppol2tp.h userspace compilation errors packet: fix races in fanout_add() ibmvnic: Fix initial MTU settings net: ethernet: ti: cpsw: fix cpsw assignment in resume kcm: fix a null pointer dereference in kcm_sendmsg() net: fec: fix multicast filtering hardware setup ipv6: Handle IPv4-mapped src to in6addr_any dst. ipv6: Inhibit IPv4-mapped src address on the wire. net/mlx5e: Disable preemption when doing TC statistics upcall rhashtable: Add nested tables tipc: Fix tipc_sk_reinit race conditions gfs2: Use rhashtable walk interface in glock_hash_walk ...
2017-02-16genirq: Clarify logic calculating bogus irqreturn_t valuesJeremy Kerr1-1/+3
Although irqreturn_t is an enum, we treat it (and its enumeration constants) as a bitmask. However, bad_action_ret() uses a less-than operator to determine whether an irqreturn_t falls within allowable bit values, which means we need to know the signededness of an enum type to read the logic, which is implementation-dependent. This change explicitly uses an unsigned type for the comparison. We do this instead of changing to a bitwise test, as the latter compiles to increased instructions in this hot path. It looks like we get the correct behaviour currently (bad_action_ret(-1) returns 1), so this is purely a readability fix. Signed-off-by: Jeremy Kerr <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
2017-02-15tracing/probes: Fix a warning message to show correct maximum lengthMasami Hiramatsu1-1/+2
Since tracing/*probe_events will accept a probe definition up to 4096 - 2 ('\n' and '\0') bytes, it must show 4094 instead of 4096 in warning message. Note that there is one possible case of exceed 4094. If user prepare 4096 bytes null-terminated string and syscall write it with the count == 4095, then it can be accepted. However, if user puts a '\n' after that, it must rejected. So IMHO, the warning message should indicate shorter one, since it is safer. Link: http://lkml.kernel.org/r/148673290462.2579.7966778294009665632.stgit@devbox Signed-off-by: Masami Hiramatsu <[email protected]> Signed-off-by: Steven Rostedt (VMware) <[email protected]>
2017-02-15tracing: Fix return value check in trace_benchmark_reg()Wei Yongjun1-2/+2
In case of error, the function kthread_run() returns ERR_PTR() and never returns NULL. The NULL test in the return value check should be replaced with IS_ERR(). Link: http://lkml.kernel.org/r/[email protected] Cc: [email protected] Fixes: 81dc9f0e ("tracing: Add tracepoint benchmark tracepoint") Signed-off-by: Wei Yongjun <[email protected]> Signed-off-by: Steven Rostedt (VMware) <[email protected]>
2017-02-15tracing: Use modern function declarationArnd Bergmann1-1/+1
We get a lot of harmless warnings about this header file at W=1 level because of an unusual function declaration: kernel/trace/trace.h:766:1: error: 'inline' is not at beginning of declaration [-Werror=old-style-declaration] This moves the inline statement where it normally belongs, avoiding the warning. Link: http://lkml.kernel.org/r/[email protected] Fixes: 4046bf023b06 ("ftrace: Expose ftrace_hash_empty and ftrace_lookup_ip") Signed-off-by: Arnd Bergmann <[email protected]> Signed-off-by: Steven Rostedt (VMware) <[email protected]>
2017-02-15jump_label: Reduce the size of struct static_keyJason Baron1-26/+127
The static_key->next field goes mostly unused. The field is used for associating module uses with a static key. Most uses of struct static_key define a static key in the core kernel and make use of it entirely within the core kernel, or define the static key in a module and make use of it only from within that module. In fact, of the ~3,000 static keys defined, I found only about 5 or so that did not fit this pattern. Thus, we can remove the static_key->next field entirely and overload the static_key->entries field. That is, when all the static_key uses are contained within the same module, static_key->entries continues to point to those uses. However, if the static_key uses are not contained within the module where the static_key is defined, then we allocate a struct static_key_mod, store a pointer to the uses within that struct static_key_mod, and have the static key point at the static_key_mod. This does incur some extra memory usage when a static_key is used in a module that does not define it, but since there are only a handful of such cases there is a net savings. In order to identify if the static_key->entries pointer contains a struct static_key_mod or a struct jump_entry pointer, bit 1 of static_key->entries is set to 1 if it points to a struct static_key_mod and is 0 if it points to a struct jump_entry. We were already using bit 0 in a similar way to store the initial value of the static_key. This does mean that allocations of struct static_key_mod and that the struct jump_entry tables need to be at least 4-byte aligned in memory. As far as I can tell all arches meet this criteria. For my .config, the patch increased the text by 778 bytes, but reduced the data + bss size by 14912, for a net savings of 14,134 bytes. text data bss dec hex filename 8092427 5016512 790528 13899467 d416cb vmlinux.pre 8093205 5001600 790528 13885333 d3df95 vmlinux.post Link: http://lkml.kernel.org/r/[email protected] Cc: Peter Zijlstra <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Joe Perches <[email protected]> Signed-off-by: Jason Baron <[email protected]> Signed-off-by: Steven Rostedt (VMware) <[email protected]>
2017-02-15tracing/probe: Show subsystem name in messagesMasami Hiramatsu3-0/+3
Show "trace_probe:", "trace_kprobe:" and "trace_uprobe:" headers for each warning/error/info message. This will help people to notice that kprobe/uprobe events caused those messages. Link: http://lkml.kernel.org/r/148646647813.24658.16705315294927615333.stgit@devbox Signed-off-by: Masami Hiramatsu <[email protected]> Signed-off-by: Steven Rostedt (VMware) <[email protected]>
2017-02-15tracing/hwlat: Update old comment about migrationLuiz Capitulino1-4/+1
The ftrace hwlat does support a cpumask. Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Luiz Capitulino <[email protected]> Signed-off-by: Steven Rostedt (VMware) <[email protected]>
2017-02-15tracing: Have traceprobe_probes_write() not access userspace unnecessarilySteven Rostedt (VMware)1-19/+29
The code in traceprobe_probes_write() reads up to 4096 bytes from userpace for each line. If userspace passes in several lines to execute, the code will do a large read for each line, even though, it is highly likely that the first read from userspace received all of the lines at once. I changed the logic to do a single read from userspace, and to only read from userspace again if not all of the read from userspace made it in. I tested this by adding printk()s and writing files that would test -1, ==, and +1 the buffer size, to make sure that there's no overflows and that if a single line is written with +1 the buffer size, that it fails properly. Link: http://lkml.kernel.org/r/[email protected] Acked-by: Masami Hiramatsu <[email protected]> Acked-by: Namhyung Kim <[email protected]> Signed-off-by: Steven Rostedt (VMware) <[email protected]>
2017-02-15timekeeping: Use deferred printk() in debug codeSergey Senozhatsky1-2/+2
We cannot do printk() from tk_debug_account_sleep_time(), because tk_debug_account_sleep_time() is called under tk_core seq lock. The reason why printk() is unsafe there is that console_sem may invoke scheduler (up()->wake_up_process()->activate_task()), which, in turn, can return back to timekeeping code, for instance, via get_time()->ktime_get(), deadlocking the system on tk_core seq lock. [ 48.950592] ====================================================== [ 48.950622] [ INFO: possible circular locking dependency detected ] [ 48.950622] 4.10.0-rc7-next-20170213+ #101 Not tainted [ 48.950622] ------------------------------------------------------- [ 48.950622] kworker/0:0/3 is trying to acquire lock: [ 48.950653] (tk_core){----..}, at: [<c01cc624>] retrigger_next_event+0x4c/0x90 [ 48.950683] but task is already holding lock: [ 48.950683] (hrtimer_bases.lock){-.-...}, at: [<c01cc610>] retrigger_next_event+0x38/0x90 [ 48.950714] which lock already depends on the new lock. [ 48.950714] the existing dependency chain (in reverse order) is: [ 48.950714] -> #5 (hrtimer_bases.lock){-.-...}: [ 48.950744] _raw_spin_lock_irqsave+0x50/0x64 [ 48.950775] lock_hrtimer_base+0x28/0x58 [ 48.950775] hrtimer_start_range_ns+0x20/0x5c8 [ 48.950775] __enqueue_rt_entity+0x320/0x360 [ 48.950805] enqueue_rt_entity+0x2c/0x44 [ 48.950805] enqueue_task_rt+0x24/0x94 [ 48.950836] ttwu_do_activate+0x54/0xc0 [ 48.950836] try_to_wake_up+0x248/0x5c8 [ 48.950836] __setup_irq+0x420/0x5f0 [ 48.950836] request_threaded_irq+0xdc/0x184 [ 48.950866] devm_request_threaded_irq+0x58/0xa4 [ 48.950866] omap_i2c_probe+0x530/0x6a0 [ 48.950897] platform_drv_probe+0x50/0xb0 [ 48.950897] driver_probe_device+0x1f8/0x2cc [ 48.950897] __driver_attach+0xc0/0xc4 [ 48.950927] bus_for_each_dev+0x6c/0xa0 [ 48.950927] bus_add_driver+0x100/0x210 [ 48.950927] driver_register+0x78/0xf4 [ 48.950958] do_one_initcall+0x3c/0x16c [ 48.950958] kernel_init_freeable+0x20c/0x2d8 [ 48.950958] kernel_init+0x8/0x110 [ 48.950988] ret_from_fork+0x14/0x24 [ 48.950988] -> #4 (&rt_b->rt_runtime_lock){-.-...}: [ 48.951019] _raw_spin_lock+0x40/0x50 [ 48.951019] rq_offline_rt+0x9c/0x2bc [ 48.951019] set_rq_offline.part.2+0x2c/0x58 [ 48.951049] rq_attach_root+0x134/0x144 [ 48.951049] cpu_attach_domain+0x18c/0x6f4 [ 48.951049] build_sched_domains+0xba4/0xd80 [ 48.951080] sched_init_smp+0x68/0x10c [ 48.951080] kernel_init_freeable+0x160/0x2d8 [ 48.951080] kernel_init+0x8/0x110 [ 48.951080] ret_from_fork+0x14/0x24 [ 48.951110] -> #3 (&rq->lock){-.-.-.}: [ 48.951110] _raw_spin_lock+0x40/0x50 [ 48.951141] task_fork_fair+0x30/0x124 [ 48.951141] sched_fork+0x194/0x2e0 [ 48.951141] copy_process.part.5+0x448/0x1a20 [ 48.951171] _do_fork+0x98/0x7e8 [ 48.951171] kernel_thread+0x2c/0x34 [ 48.951171] rest_init+0x1c/0x18c [ 48.951202] start_kernel+0x35c/0x3d4 [ 48.951202] 0x8000807c [ 48.951202] -> #2 (&p->pi_lock){-.-.-.}: [ 48.951232] _raw_spin_lock_irqsave+0x50/0x64 [ 48.951232] try_to_wake_up+0x30/0x5c8 [ 48.951232] up+0x4c/0x60 [ 48.951263] __up_console_sem+0x2c/0x58 [ 48.951263] console_unlock+0x3b4/0x650 [ 48.951263] vprintk_emit+0x270/0x474 [ 48.951293] vprintk_default+0x20/0x28 [ 48.951293] printk+0x20/0x30 [ 48.951324] kauditd_hold_skb+0x94/0xb8 [ 48.951324] kauditd_thread+0x1a4/0x56c [ 48.951324] kthread+0x104/0x148 [ 48.951354] ret_from_fork+0x14/0x24 [ 48.951354] -> #1 ((console_sem).lock){-.....}: [ 48.951385] _raw_spin_lock_irqsave+0x50/0x64 [ 48.951385] down_trylock+0xc/0x2c [ 48.951385] __down_trylock_console_sem+0x24/0x80 [ 48.951385] console_trylock+0x10/0x8c [ 48.951416] vprintk_emit+0x264/0x474 [ 48.951416] vprintk_default+0x20/0x28 [ 48.951416] printk+0x20/0x30 [ 48.951446] tk_debug_account_sleep_time+0x5c/0x70 [ 48.951446] __timekeeping_inject_sleeptime.constprop.3+0x170/0x1a0 [ 48.951446] timekeeping_resume+0x218/0x23c [ 48.951477] syscore_resume+0x94/0x42c [ 48.951477] suspend_enter+0x554/0x9b4 [ 48.951477] suspend_devices_and_enter+0xd8/0x4b4 [ 48.951507] enter_state+0x934/0xbd4 [ 48.951507] pm_suspend+0x14/0x70 [ 48.951507] state_store+0x68/0xc8 [ 48.951538] kernfs_fop_write+0xf4/0x1f8 [ 48.951538] __vfs_write+0x1c/0x114 [ 48.951538] vfs_write+0xa0/0x168 [ 48.951568] SyS_write+0x3c/0x90 [ 48.951568] __sys_trace_return+0x0/0x10 [ 48.951568] -> #0 (tk_core){----..}: [ 48.951599] lock_acquire+0xe0/0x294 [ 48.951599] ktime_get_update_offsets_now+0x5c/0x1d4 [ 48.951629] retrigger_next_event+0x4c/0x90 [ 48.951629] on_each_cpu+0x40/0x7c [ 48.951629] clock_was_set_work+0x14/0x20 [ 48.951660] process_one_work+0x2b4/0x808 [ 48.951660] worker_thread+0x3c/0x550 [ 48.951660] kthread+0x104/0x148 [ 48.951690] ret_from_fork+0x14/0x24 [ 48.951690] other info that might help us debug this: [ 48.951690] Chain exists of: tk_core --> &rt_b->rt_runtime_lock --> hrtimer_bases.lock [ 48.951721] Possible unsafe locking scenario: [ 48.951721] CPU0 CPU1 [ 48.951721] ---- ---- [ 48.951721] lock(hrtimer_bases.lock); [ 48.951751] lock(&rt_b->rt_runtime_lock); [ 48.951751] lock(hrtimer_bases.lock); [ 48.951751] lock(tk_core); [ 48.951782] *** DEADLOCK *** [ 48.951782] 3 locks held by kworker/0:0/3: [ 48.951782] #0: ("events"){.+.+.+}, at: [<c0156590>] process_one_work+0x1f8/0x808 [ 48.951812] #1: (hrtimer_work){+.+...}, at: [<c0156590>] process_one_work+0x1f8/0x808 [ 48.951843] #2: (hrtimer_bases.lock){-.-...}, at: [<c01cc610>] retrigger_next_event+0x38/0x90 [ 48.951843] stack backtrace: [ 48.951873] CPU: 0 PID: 3 Comm: kworker/0:0 Not tainted 4.10.0-rc7-next-20170213+ [ 48.951904] Workqueue: events clock_was_set_work [ 48.951904] [<c0110208>] (unwind_backtrace) from [<c010c224>] (show_stack+0x10/0x14) [ 48.951934] [<c010c224>] (show_stack) from [<c04ca6c0>] (dump_stack+0xac/0xe0) [ 48.951934] [<c04ca6c0>] (dump_stack) from [<c019b5cc>] (print_circular_bug+0x1d0/0x308) [ 48.951965] [<c019b5cc>] (print_circular_bug) from [<c019d2a8>] (validate_chain+0xf50/0x1324) [ 48.951965] [<c019d2a8>] (validate_chain) from [<c019ec18>] (__lock_acquire+0x468/0x7e8) [ 48.951995] [<c019ec18>] (__lock_acquire) from [<c019f634>] (lock_acquire+0xe0/0x294) [ 48.951995] [<c019f634>] (lock_acquire) from [<c01d0ea0>] (ktime_get_update_offsets_now+0x5c/0x1d4) [ 48.952026] [<c01d0ea0>] (ktime_get_update_offsets_now) from [<c01cc624>] (retrigger_next_event+0x4c/0x90) [ 48.952026] [<c01cc624>] (retrigger_next_event) from [<c01e4e24>] (on_each_cpu+0x40/0x7c) [ 48.952056] [<c01e4e24>] (on_each_cpu) from [<c01cafc4>] (clock_was_set_work+0x14/0x20) [ 48.952056] [<c01cafc4>] (clock_was_set_work) from [<c015664c>] (process_one_work+0x2b4/0x808) [ 48.952087] [<c015664c>] (process_one_work) from [<c0157774>] (worker_thread+0x3c/0x550) [ 48.952087] [<c0157774>] (worker_thread) from [<c015d644>] (kthread+0x104/0x148) [ 48.952087] [<c015d644>] (kthread) from [<c0107830>] (ret_from_fork+0x14/0x24) Replace printk() with printk_deferred(), which does not call into the scheduler. Fixes: 0bf43f15db85 ("timekeeping: Prints the amounts of time spent during suspend") Reported-and-tested-by: Tony Lindgren <[email protected]> Signed-off-by: Sergey Senozhatsky <[email protected]> Cc: Petr Mladek <[email protected]> Cc: Sergey Senozhatsky <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: "Rafael J . Wysocki" <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: John Stultz <[email protected]> Cc: "[4.9+]" <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
2017-02-14bpf: reduce compiler warnings by adding fallthrough commentsAlexander Alemayhu1-0/+5
Fixes the following warnings: kernel/bpf/verifier.c: In function ‘may_access_direct_pkt_data’: kernel/bpf/verifier.c:702:6: warning: this statement may fall through [-Wimplicit-fallthrough=] if (t == BPF_WRITE) ^ kernel/bpf/verifier.c:704:2: note: here case BPF_PROG_TYPE_SCHED_CLS: ^~~~ kernel/bpf/verifier.c: In function ‘reg_set_min_max_inv’: kernel/bpf/verifier.c:2057:23: warning: this statement may fall through [-Wimplicit-fallthrough=] true_reg->min_value = 0; ~~~~~~~~~~~~~~~~~~~~^~~ kernel/bpf/verifier.c:2058:2: note: here case BPF_JSGT: ^~~~ kernel/bpf/verifier.c:2068:23: warning: this statement may fall through [-Wimplicit-fallthrough=] true_reg->min_value = 0; ~~~~~~~~~~~~~~~~~~~~^~~ kernel/bpf/verifier.c:2069:2: note: here case BPF_JSGE: ^~~~ kernel/bpf/verifier.c: In function ‘reg_set_min_max’: kernel/bpf/verifier.c:2009:24: warning: this statement may fall through [-Wimplicit-fallthrough=] false_reg->min_value = 0; ~~~~~~~~~~~~~~~~~~~~~^~~ kernel/bpf/verifier.c:2010:2: note: here case BPF_JSGT: ^~~~ kernel/bpf/verifier.c:2019:24: warning: this statement may fall through [-Wimplicit-fallthrough=] false_reg->min_value = 0; ~~~~~~~~~~~~~~~~~~~~~^~~ kernel/bpf/verifier.c:2020:2: note: here case BPF_JSGE: ^~~~ Reported-by: David Binderman <[email protected]> Signed-off-by: Alexander Alemayhu <[email protected]> Acked-by: Daniel Borkmann <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Signed-off-by: David S. Miller <[email protected]>
2017-02-14audit: remove unnecessary curly braces from switch/case statementsPaul Moore1-12/+12
Signed-off-by: Paul Moore <[email protected]>
2017-02-14Merge tag 'v4.10-rc8' into perf/core, to pick up fixesIngo Molnar7-63/+81
Signed-off-by: Ingo Molnar <[email protected]>
2017-02-13audit: log module name on init_moduleRichard Guy Briggs3-1/+21
This adds a new auxiliary record MODULE_INIT to the SYSCALL event. We get finit_module for free since it made most sense to hook this in to load_module(). https://github.com/linux-audit/audit-kernel/issues/7 https://github.com/linux-audit/audit-kernel/wiki/RFE-Module-Load-Record-Format Signed-off-by: Richard Guy Briggs <[email protected]> Acked-by: Jessica Yu <[email protected]> [PM: corrected links in the commit description] Signed-off-by: Paul Moore <[email protected]>
2017-02-13futex: Move futex_init() to core_initcallYang Yang1-1/+1
The UEVENT user mode helper is enabled before the initcalls are executed and is available when the root filesystem has been mounted. The user mode helper is triggered by device init calls and the executable might use the futex syscall. futex_init() is marked __initcall which maps to device_initcall, but there is no guarantee that futex_init() is invoked _before_ the first device init call which triggers the UEVENT user mode helper. If the user mode helper uses the futex syscall before futex_init() then the syscall crashes with a NULL pointer dereference because the futex subsystem has not been initialized yet. Move futex_init() to core_initcall so futexes are initialized before the root filesystem is mounted and the usermode helper becomes available. [ tglx: Rewrote changelog ] Signed-off-by: Yang Yang <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: Peter Zijlstra <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
2017-02-13tick/broadcast: Prevent deadlock on tick_broadcast_lockMike Galbraith1-8/+7
tick_broadcast_lock is taken from interrupt context, but the following call chain takes the lock without disabling interrupts: [ 12.703736] _raw_spin_lock+0x3b/0x50 [ 12.703738] tick_broadcast_control+0x5a/0x1a0 [ 12.703742] intel_idle_cpu_online+0x22/0x100 [ 12.703744] cpuhp_invoke_callback+0x245/0x9d0 [ 12.703752] cpuhp_thread_fun+0x52/0x110 [ 12.703754] smpboot_thread_fn+0x276/0x320 So the following deadlock can happen: lock(tick_broadcast_lock); <Interrupt> lock(tick_broadcast_lock); intel_idle_cpu_online() is the only place which violates the calling convention of tick_broadcast_control(). This was caused by the removal of the smp function call in course of the cpu hotplug rework. Instead of slapping local_irq_disable/enable() at the call site, we can relax the calling convention and handle it in the core code, which makes the whole machinery more robust. Fixes: 29d7bbada98e ("intel_idle: Remove superfluous SMP fuction call") Reported-by: Gabriel C <[email protected]> Signed-off-by: Mike Galbraith <[email protected]> Cc: Ruslan Ruslichenko <[email protected]> Cc: Jiri Slaby <[email protected]> Cc: Greg KH <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: [email protected] Cc: Andrew Morton <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Anna-Maria Gleixner <[email protected]> Cc: Sebastian Siewior <[email protected]> Cc: stable <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
2017-02-12bpf: introduce BPF_F_ALLOW_OVERRIDE flagAlexei Starovoitov3-22/+66
If BPF_F_ALLOW_OVERRIDE flag is used in BPF_PROG_ATTACH command to the given cgroup the descendent cgroup will be able to override effective bpf program that was inherited from this cgroup. By default it's not passed, therefore override is disallowed. Examples: 1. prog X attached to /A with default prog Y fails to attach to /A/B and /A/B/C Everything under /A runs prog X 2. prog X attached to /A with allow_override. prog Y fails to attach to /A/B with default (non-override) prog M attached to /A/B with allow_override. Everything under /A/B runs prog M only. 3. prog X attached to /A with allow_override. prog Y fails to attach to /A with default. The user has to detach first to switch the mode. In the future this behavior may be extended with a chain of non-overridable programs. Also fix the bug where detach from cgroup where nothing is attached was not throwing error. Return ENOENT in such case. Add several testcases and adjust libbpf. Fixes: 3007098494be ("cgroup: add support for eBPF programs") Signed-off-by: Alexei Starovoitov <[email protected]> Acked-by: Daniel Borkmann <[email protected]> Acked-by: Tejun Heo <[email protected]> Acked-by: Daniel Mack <[email protected]> Signed-off-by: David S. Miller <[email protected]>
2017-02-12genirq/devres: Use dev_name(dev) as default for devnameHeiner Kallweit1-2/+8
Allow the devname parameter to be NULL and use dev_name(dev) in this case. This should be an appropriate default for most use cases. Signed-off-by: Heiner Kallweit <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
2017-02-11Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds1-0/+5
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fix from Ingo Molnar: "Fix a sporadic missed timer hw reprogramming bug that can result in random delays" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: tick/nohz: Fix possible missing clock reprog after tick soft restart
2017-02-11Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds1-10/+15
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "A kernel crash fix plus three tooling fixes" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/core: Fix crash in perf_event_read() perf callchain: Reference count maps perf diff: Fix -o/--order option behavior (again) perf diff: Fix segfault on 'perf diff -o N' option
2017-02-11Merge branch 'locking-urgent-for-linus' of ↵Linus Torvalds1-8/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull lockdep fix from Ingo Molnar: "This fixes an ugly lockdep stack trace output regression. (But also affects other stacktrace users such as kmemleak, KASAN, etc)" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: stacktrace, lockdep: Fix address, newline ugliness
2017-02-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-2/+1
2017-02-10module: Optimize search_module_extables()Peter Zijlstra1-13/+14
While looking through the __ex_table stuff I found that we do a linear lookup of the module. Also fix up a comment. Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Acked-by: Mark Rutland <[email protected]> Signed-off-by: Jessica Yu <[email protected]>
2017-02-10tracing: Have COMM event filter key be treated as a stringSteven Rostedt (VMware)1-1/+2
The GLOB operation "~" should be able to work with the COMM filter key in order to trace programs with a glob. For example echo 'COMM ~ "systemd*"' > events/syscalls/filter Signed-off-by: Steven Rostedt (VMware) <[email protected]>
2017-02-10genirq: Fix /proc/interrupts output alignmentH Hartley Sweeten1-0/+2
If the irq_desc being output does not have a domain associated the information following the 'name' is not aligned correctly. Signed-off-by: H Hartley Sweeten <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
2017-02-10Merge branches 'iommu/fixes', 'arm/exynos', 'arm/renesas', 'arm/smmu', ↵Joerg Roedel35-238/+538
'arm/mediatek', 'arm/core', 'x86/vt-d' and 'core' into next
2017-02-10irqdesc: Add a resource managed version of irq_alloc_descs()Bartosz Golaszewski1-0/+55
Add a devres flavor of __devm_irq_alloc_descs() and corresponding helper macros. Signed-off-by: Bartosz Golaszewski <[email protected]> Cc: Marc Zyngier <[email protected]> Cc: [email protected] Cc: Jonathan Corbet <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
2017-02-10timer_list: Remove useless cast when printingMars Cheng1-1/+1
hrtimer_resolution is already unsigned int, not necessary to cast it when printing. Signed-off-by: Mars Cheng <[email protected]> Cc: CC Hwang <[email protected]> Cc: [email protected] Cc: Loda Chou <[email protected]> Cc: Jades Shih <[email protected]> Cc: Miles Chen <[email protected]> Cc: John Stultz <[email protected]> Cc: My Chuang <[email protected]> Cc: Matthias Brugger <[email protected]> Cc: Yingjoe Chen <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
2017-02-10time: Remove CONFIG_TIMER_STATSKees Cook7-523/+2
Currently CONFIG_TIMER_STATS exposes process information across namespaces: kernel/time/timer_list.c print_timer(): SEQ_printf(m, ", %s/%d", tmp, timer->start_pid); /proc/timer_list: #11: <0000000000000000>, hrtimer_wakeup, S:01, do_nanosleep, cron/2570 Given that the tracer can give the same information, this patch entirely removes CONFIG_TIMER_STATS. Suggested-by: Thomas Gleixner <[email protected]> Signed-off-by: Kees Cook <[email protected]> Acked-by: John Stultz <[email protected]> Cc: Nicolas Pitre <[email protected]> Cc: [email protected] Cc: Lai Jiangshan <[email protected]> Cc: Shuah Khan <[email protected]> Cc: Xing Gao <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Jessica Frazelle <[email protected]> Cc: [email protected] Cc: Nicolas Iooss <[email protected]> Cc: "Paul E. McKenney" <[email protected]> Cc: Petr Mladek <[email protected]> Cc: Richard Cochran <[email protected]> Cc: Tejun Heo <[email protected]> Cc: Michal Marek <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: "Eric W. Biederman" <[email protected]> Cc: Olof Johansson <[email protected]> Cc: Andrew Morton <[email protected]> Cc: [email protected] Cc: Arjan van de Ven <[email protected]> Link: http://lkml.kernel.org/r/20170208192659.GA32582@beast Signed-off-by: Thomas Gleixner <[email protected]>
2017-02-10tick/nohz: Fix possible missing clock reprog after tick soft restartFrederic Weisbecker1-0/+5
ts->next_tick keeps track of the next tick deadline in order to optimize clock programmation on irq exit and avoid redundant clock device writes. Now if ts->next_tick missed an update, we may spuriously miss a clock reprog later as the nohz code is fooled by an obsolete next_tick value. This is what happens here on a specific path: when we observe an expired timer from the nohz update code on irq exit, we perform a soft tick restart which simply fires the closest possible tick without actually exiting the nohz mode and restoring a periodic state. But we forget to update ts->next_tick accordingly. As a result, after the next tick resulting from such soft tick restart, the nohz code sees a stale value on ts->next_tick which doesn't match the clock deadline that just expired. If that obsolete ts->next_tick value happens to collide with the actual next tick deadline to be scheduled, we may spuriously bypass the clock reprogramming. In the worst case, the tick may never fire again. Fix this with a ts->next_tick reset on soft tick restart. Signed-off-by: Frederic Weisbecker <[email protected]> Reviewed: Wanpeng Li <[email protected]> Acked-by: Rik van Riel <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
2017-02-10locking/spinlock/debug: Remove spinlock lockup detection codeWaiman Long1-81/+5
The current spinlock lockup detection code can sometimes produce false positives because of the unfairness of the locking algorithm itself. So the lockup detection code is now removed. Instead, we are relying on the NMI watchdog to detect potential lockup. We won't have lockup detection if the watchdog isn't running. The commented-out read-write lock lockup detection code are also removed. Signed-off-by: Waiman Long <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Sasha Levin <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2017-02-10lockdep: Fix incorrect condition to print bug msgs for MAX_LOCKDEP_CHAIN_HLOCKSByungchul Park1-1/+1
Bug messages and stack dump for MAX_LOCKDEP_CHAIN_HLOCKS should only be printed once. Signed-off-by: Byungchul Park <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Sasha Levin <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>