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2013-05-06irqdomain: Allow quiet failure modeBenjamin Herrenschmidt1-3/+17
Some interrupt controllers refuse to map interrupts marked as "protected" by firwmare. Since we try to map everyting in the device-tree on some platforms, we end up with a lot of nasty WARN's in the boot log for what is a normal situation on those machines. This defines a specific return code (-EPERM) from the host map() callback which cause irqdomain to fail silently. MPIC is updated to return this when hitting a protected source printing only a single line message for diagnostic purposes. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-05Merge branch 'timers-nohz-for-linus' of ↵Linus Torvalds16-88/+607
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull 'full dynticks' support from Ingo Molnar: "This tree from Frederic Weisbecker adds a new, (exciting! :-) core kernel feature to the timer and scheduler subsystems: 'full dynticks', or CONFIG_NO_HZ_FULL=y. This feature extends the nohz variable-size timer tick feature from idle to busy CPUs (running at most one task) as well, potentially reducing the number of timer interrupts significantly. This feature got motivated by real-time folks and the -rt tree, but the general utility and motivation of full-dynticks runs wider than that: - HPC workloads get faster: CPUs running a single task should be able to utilize a maximum amount of CPU power. A periodic timer tick at HZ=1000 can cause a constant overhead of up to 1.0%. This feature removes that overhead - and speeds up the system by 0.5%-1.0% on typical distro configs even on modern systems. - Real-time workload latency reduction: CPUs running critical tasks should experience as little jitter as possible. The last remaining source of kernel-related jitter was the periodic timer tick. - A single task executing on a CPU is a pretty common situation, especially with an increasing number of cores/CPUs, so this feature helps desktop and mobile workloads as well. The cost of the feature is mainly related to increased timer reprogramming overhead when a CPU switches its tick period, and thus slightly longer to-idle and from-idle latency. Configuration-wise a third mode of operation is added to the existing two NOHZ kconfig modes: - CONFIG_HZ_PERIODIC: [formerly !CONFIG_NO_HZ], now explicitly named as a config option. This is the traditional Linux periodic tick design: there's a HZ tick going on all the time, regardless of whether a CPU is idle or not. - CONFIG_NO_HZ_IDLE: [formerly CONFIG_NO_HZ=y], this turns off the periodic tick when a CPU enters idle mode. - CONFIG_NO_HZ_FULL: this new mode, in addition to turning off the tick when a CPU is idle, also slows the tick down to 1 Hz (one timer interrupt per second) when only a single task is running on a CPU. The .config behavior is compatible: existing !CONFIG_NO_HZ and CONFIG_NO_HZ=y settings get translated to the new values, without the user having to configure anything. CONFIG_NO_HZ_FULL is turned off by default. This feature is based on a lot of infrastructure work that has been steadily going upstream in the last 2-3 cycles: related RCU support and non-periodic cputime support in particular is upstream already. This tree adds the final pieces and activates the feature. The pull request is marked RFC because: - it's marked 64-bit only at the moment - the 32-bit support patch is small but did not get ready in time. - it has a number of fresh commits that came in after the merge window. The overwhelming majority of commits are from before the merge window, but still some aspects of the tree are fresh and so I marked it RFC. - it's a pretty wide-reaching feature with lots of effects - and while the components have been in testing for some time, the full combination is still not very widely used. That it's default-off should reduce its regression abilities and obviously there are no known regressions with CONFIG_NO_HZ_FULL=y enabled either. - the feature is not completely idempotent: there is no 100% equivalent replacement for a periodic scheduler/timer tick. In particular there's ongoing work to map out and reduce its effects on scheduler load-balancing and statistics. This should not impact correctness though, there are no known regressions related to this feature at this point. - it's a pretty ambitious feature that with time will likely be enabled by most Linux distros, and we'd like you to make input on its design/implementation, if you dislike some aspect we missed. Without flaming us to crisp! :-) Future plans: - there's ongoing work to reduce 1Hz to 0Hz, to essentially shut off the periodic tick altogether when there's a single busy task on a CPU. We'd first like 1 Hz to be exposed more widely before we go for the 0 Hz target though. - once we reach 0 Hz we can remove the periodic tick assumption from nr_running>=2 as well, by essentially interrupting busy tasks only as frequently as the sched_latency constraints require us to do - once every 4-40 msecs, depending on nr_running. I am personally leaning towards biting the bullet and doing this in v3.10, like the -rt tree this effort has been going on for too long - but the final word is up to you as usual. More technical details can be found in Documentation/timers/NO_HZ.txt" * 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits) sched: Keep at least 1 tick per second for active dynticks tasks rcu: Fix full dynticks' dependency on wide RCU nocb mode nohz: Protect smp_processor_id() in tick_nohz_task_switch() nohz_full: Add documentation. cputime_nsecs: use math64.h for nsec resolution conversion helpers nohz: Select VIRT_CPU_ACCOUNTING_GEN from full dynticks config nohz: Reduce overhead under high-freq idling patterns nohz: Remove full dynticks' superfluous dependency on RCU tree nohz: Fix unavailable tick_stop tracepoint in dynticks idle nohz: Add basic tracing nohz: Select wide RCU nocb for full dynticks nohz: Disable the tick when irq resume in full dynticks CPU nohz: Re-evaluate the tick for the new task after a context switch nohz: Prepare to stop the tick on irq exit nohz: Implement full dynticks kick nohz: Re-evaluate the tick from the scheduler IPI sched: New helper to prevent from stopping the tick in full dynticks sched: Kick full dynticks CPU that have more than one task enqueued. perf: New helper to prevent full dynticks CPUs from stopping tick perf: Kick full dynticks CPU if events rotation is needed ...
2013-05-05Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds1-4/+10
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "Misc fixes plus a small hw-enablement patch for Intel IB model 58 uncore events" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/intel/lbr: Demand proper privileges for PERF_SAMPLE_BRANCH_KERNEL perf/x86/intel/lbr: Fix LBR filter perf/x86: Blacklist all MEM_*_RETIRED events for Ivy Bridge perf: Fix vmalloc ring buffer pages handling perf/x86/intel: Fix unintended variable name reuse perf/x86/intel: Add support for IvyBridge model 58 Uncore perf/x86/intel: Fix typo in perf_event_intel_uncore.c x86: Eliminate irq_mis_count counted in arch_irq_stat
2013-05-05Merge tag 'modules-next-for-linus' of ↵Linus Torvalds4-25/+34
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull mudule updates from Rusty Russell: "We get rid of the general module prefix confusion with a binary config option, fix a remove/insert race which Never Happens, and (my favorite) handle the case when we have too many modules for a single commandline. Seriously, the kernel is full, please go away!" * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: modpost: fix unwanted VMLINUX_SYMBOL_STR expansion X.509: Support parse long form of length octets in Authority Key Identifier module: don't unlink the module until we've removed all exposure. kernel: kallsyms: memory override issue, need check destination buffer length MODSIGN: do not send garbage to stderr when enabling modules signature modpost: handle huge numbers of modules. modpost: add -T option to read module names from file/stdin. modpost: minor cleanup. genksyms: pass symbol-prefix instead of arch module: fix symbol versioning with symbol prefixes CONFIG_SYMBOL_PREFIX: cleanup.
2013-05-05rcutrace: single_open() leaksAl Viro1-4/+4
Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-04Merge branch 'for-linus' of ↵Linus Torvalds1-1/+6
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull second round of VFS updates from Al Viro: "Assorted fixes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: xtensa simdisk: fix braino in "xtensa simdisk: switch to proc_create_data()" hostfs: use kmalloc instead of kzalloc hostfs: move HOSTFS_SUPER_MAGIC to <linux/magic.h> hostfs: remove "will unlock" comment vfs: use list_move instead of list_del/list_add proc_devtree: Replace include linux/module.h with linux/export.h create_mnt_ns: unidiomatic use of list_add() fs: remove dentry_lru_prune() Removed unused typedef to avoid "unused local typedef" warnings. kill fs/read_write.h fs: Fix hang with BSD accounting on frozen filesystem sun3_scsi: add ->show_info() nubus: Kill nubus_proc_detach_device() more mode_t whack-a-mole... do_coredump(): don't wait for thaw if coredump has already been interrupted do_mount(): fix a leak introduced in 3.9 ("mount: consolidate permission checks")
2013-05-04fs: Fix hang with BSD accounting on frozen filesystemJan Kara1-1/+6
When BSD process accounting is enabled and logs information to a filesystem which gets frozen, system easily becomes unusable because each attempt to account process information blocks. Thus e.g. every task gets blocked in exit. It seems better to drop accounting information (which can already happen when filesystem is running out of space) instead of locking system up. So we just skip the write if the filesystem is frozen. Reported-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-04sched: Keep at least 1 tick per second for active dynticks tasksFrederic Weisbecker4-0/+48
The scheduler doesn't yet fully support environments with a single task running without a periodic tick. In order to ensure we still maintain the duties of scheduler_tick(), keep at least 1 tick per second. This makes sure that we keep the progression of various scheduler accounting and background maintainance even with a very low granularity. Examples include cpu load, sched average, CFS entity vruntime, avenrun and events such as load balancing, amongst other details handled in sched_class::task_tick(). This limitation will be removed in the future once we get these individual items to work in full dynticks CPUs. Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Christoph Lameter <cl@linux.com> Cc: Hakan Akkan <hakanakkan@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Kevin Hilman <khilman@linaro.org> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de>
2013-05-04rcu: Fix full dynticks' dependency on wide RCU nocb modeFrederic Weisbecker1-1/+0
Commit 0637e029392386e6996f5d6574aadccee8315efa ("nohz: Select wide RCU nocb for full dynticks") intended to force CONFIG_RCU_NOCB_CPU_ALL=y when full dynticks is enabled. However this option is part of a choice menu and Kconfig's "select" instruction has no effect on such targets. Fix this by using reverse dependencies on the targets we don't want instead. Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Christoph Lameter <cl@linux.com> Cc: Hakan Akkan <hakanakkan@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Kevin Hilman <khilman@linaro.org> Cc: Li Zhong <zhong@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de>
2013-05-02Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linuxLinus Torvalds1-0/+116
Pull drm updates from Dave Airlie: "This is the main drm pull request for 3.10. Wierd bits: - OMAP drm changes required OMAP dss changes, in drivers/video, so I took them in here. - one more fbcon fix for font handover - VT switch avoidance in pm code - scatterlist helpers for gpu drivers - have acks from akpm Highlights: - qxl kms driver - driver for the spice qxl virtual GPU Nouveau: - fermi/kepler VRAM compression - GK110/nvf0 modesetting support. Tegra: - host1x core merged with 2D engine support i915: - vt switchless resume - more valleyview support - vblank fixes - modesetting pipe config rework radeon: - UVD engine support - SI chip tiling support - GPU registers initialisation from golden values. exynos: - device tree changes - fimc block support Otherwise: - bunches of fixes all over the place." * 'drm-next' of git://people.freedesktop.org/~airlied/linux: (513 commits) qxl: update to new idr interfaces. drm/nouveau: fix build with nv50->nvc0 drm/radeon: fix handling of v6 power tables drm/radeon: clarify family checks in pm table parsing drm/radeon: consolidate UVD clock programming drm/radeon: fix UPLL_REF_DIV_MASK definition radeon: add bo tracking debugfs drm/radeon: add new richland pci ids drm/radeon: add some new SI PCI ids drm/radeon: fix scratch reg handling for UVD fence drm/radeon: allocate SA bo in the requested domain drm/radeon: fix possible segfault when parsing pm tables drm/radeon: fix endian bugs in atom_allocate_fb_scratch() OMAPDSS: TFP410: return EPROBE_DEFER if the i2c adapter not found OMAPDSS: VENC: Add error handling for venc_probe_pdata OMAPDSS: HDMI: Add error handling for hdmi_probe_pdata OMAPDSS: RFBI: Add error handling for rfbi_probe_pdata OMAPDSS: DSI: Add error handling for dsi_probe_pdata OMAPDSS: SDI: Add error handling for sdi_probe_pdata OMAPDSS: DPI: Add error handling for dpi_probe_pdata ...
2013-05-02Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds1-29/+51
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar: "This fixes the cputime scaling overflow problems for good without having bad 32-bit overhead, and gets rid of the div64_u64_rem() helper as well." * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Revert "math64: New div64_u64_rem helper" sched: Avoid prev->stime underflow sched: Do not account bogus utime sched: Avoid cputime scaling overflow
2013-05-02Merge commit '8700c95adb03' into timers/nohzFrederic Weisbecker84-4072/+8743
The full dynticks tree needs the latest RCU and sched upstream updates in order to fix some dependencies. Merge a common upstream merge point that has these updates. Conflicts: include/linux/perf_event.h kernel/rcutree.h kernel/rcutree_plugin.h Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2013-05-01Merge branch 'for-linus' of ↵Linus Torvalds14-58/+26
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull VFS updates from Al Viro, Misc cleanups all over the place, mainly wrt /proc interfaces (switch create_proc_entry to proc_create(), get rid of the deprecated create_proc_read_entry() in favor of using proc_create_data() and seq_file etc). 7kloc removed. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits) don't bother with deferred freeing of fdtables proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h proc: Make the PROC_I() and PDE() macros internal to procfs proc: Supply a function to remove a proc entry by PDE take cgroup_open() and cpuset_open() to fs/proc/base.c ppc: Clean up scanlog ppc: Clean up rtas_flash driver somewhat hostap: proc: Use remove_proc_subtree() drm: proc: Use remove_proc_subtree() drm: proc: Use minor->index to label things, not PDE->name drm: Constify drm_proc_list[] zoran: Don't print proc_dir_entry data in debug reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show() proc: Supply an accessor for getting the data from a PDE's parent airo: Use remove_proc_subtree() rtl8192u: Don't need to save device proc dir PDE rtl8187se: Use a dir under /proc/net/r8180/ proc: Add proc_mkdir_data() proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h} proc: Move PDE_NET() to fs/proc/proc_net.c ...
2013-05-01proc: Supply a function to remove a proc entry by PDEDavid Howells1-5/+1
Supply a function (proc_remove()) to remove a proc entry (and any subtree rooted there) by proc_dir_entry pointer rather than by name and (optionally) root dir entry pointer. This allows us to eliminate all remaining pde->name accesses outside of procfs. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Grant Likely <grant.likely@linaro.or> cc: linux-acpi@vger.kernel.org cc: openipmi-developer@lists.sourceforge.net cc: devicetree-discuss@lists.ozlabs.org cc: linux-pci@vger.kernel.org cc: netdev@vger.kernel.org cc: netfilter-devel@vger.kernel.org cc: alsa-devel@alsa-project.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-01take cgroup_open() and cpuset_open() to fs/proc/base.cAl Viro2-28/+2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-01proc: Split the namespace stuff out into linux/proc_ns.hDavid Howells6-7/+8
Split the proc namespace stuff out into linux/proc_ns.h. Signed-off-by: David Howells <dhowells@redhat.com> cc: netdev@vger.kernel.org cc: Serge E. Hallyn <serge.hallyn@ubuntu.com> cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-01proc: Supply PDE attribute setting accessor functionsDavid Howells2-2/+2
Supply accessor functions to set attributes in proc_dir_entry structs. The following are supplied: proc_set_size() and proc_set_user(). Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com> cc: linuxppc-dev@lists.ozlabs.org cc: linux-media@vger.kernel.org cc: netdev@vger.kernel.org cc: linux-wireless@vger.kernel.org cc: linux-pci@vger.kernel.org cc: netfilter-devel@vger.kernel.org cc: alsa-devel@alsa-project.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds2-5/+7
Pull networking updates from David Miller: "Highlights (1721 non-merge commits, this has to be a record of some sort): 1) Add 'random' mode to team driver, from Jiri Pirko and Eric Dumazet. 2) Make it so that any driver that supports configuration of multiple MAC addresses can provide the forwarding database add and del calls by providing a default implementation and hooking that up if the driver doesn't have an explicit set of handlers. From Vlad Yasevich. 3) Support GSO segmentation over tunnels and other encapsulating devices such as VXLAN, from Pravin B Shelar. 4) Support L2 GRE tunnels in the flow dissector, from Michael Dalton. 5) Implement Tail Loss Probe (TLP) detection in TCP, from Nandita Dukkipati. 6) In the PHY layer, allow supporting wake-on-lan in situations where the PHY registers have to be written for it to be configured. Use it to support wake-on-lan in mv643xx_eth. From Michael Stapelberg. 7) Significantly improve firewire IPV6 support, from YOSHIFUJI Hideaki. 8) Allow multiple packets to be sent in a single transmission using network coding in batman-adv, from Martin Hundebøll. 9) Add support for T5 cxgb4 chips, from Santosh Rastapur. 10) Generalize the VXLAN forwarding tables so that there is more flexibility in configurating various aspects of the endpoints. From David Stevens. 11) Support RSS and TSO in hardware over GRE tunnels in bxn2x driver, from Dmitry Kravkov. 12) Zero copy support in nfnelink_queue, from Eric Dumazet and Pablo Neira Ayuso. 13) Start adding networking selftests. 14) In situations of overload on the same AF_PACKET fanout socket, or per-cpu packet receive queue, minimize drop by distributing the load to other cpus/fanouts. From Willem de Bruijn and Eric Dumazet. 15) Add support for new payload offset BPF instruction, from Daniel Borkmann. 16) Convert several drivers over to mdoule_platform_driver(), from Sachin Kamat. 17) Provide a minimal BPF JIT image disassembler userspace tool, from Daniel Borkmann. 18) Rewrite F-RTO implementation in TCP to match the final specification of it in RFC4138 and RFC5682. From Yuchung Cheng. 19) Provide netlink socket diag of netlink sockets ("Yo dawg, I hear you like netlink, so I implemented netlink dumping of netlink sockets.") From Andrey Vagin. 20) Remove ugly passing of rtnetlink attributes into rtnl_doit functions, from Thomas Graf. 21) Allow userspace to be able to see if a configuration change occurs in the middle of an address or device list dump, from Nicolas Dichtel. 22) Support RFC3168 ECN protection for ipv6 fragments, from Hannes Frederic Sowa. 23) Increase accuracy of packet length used by packet scheduler, from Jason Wang. 24) Beginning set of changes to make ipv4/ipv6 fragment handling more scalable and less susceptible to overload and locking contention, from Jesper Dangaard Brouer. 25) Get rid of using non-type-safe NLMSG_* macros and use nlmsg_*() instead. From Hong Zhiguo. 26) Optimize route usage in IPVS by avoiding reference counting where possible, from Julian Anastasov. 27) Convert IPVS schedulers to RCU, also from Julian Anastasov. 28) Support cpu fanouts in xt_NFQUEUE netfilter target, from Holger Eitzenberger. 29) Network namespace support for nf_log, ebt_log, xt_LOG, ipt_ULOG, nfnetlink_log, and nfnetlink_queue. From Gao feng. 30) Implement RFC3168 ECN protection, from Hannes Frederic Sowa. 31) Support several new r8169 chips, from Hayes Wang. 32) Support tokenized interface identifiers in ipv6, from Daniel Borkmann. 33) Use usbnet_link_change() helper in USB net driver, from Ming Lei. 34) Add 802.1ad vlan offload support, from Patrick McHardy. 35) Support mmap() based netlink communication, also from Patrick McHardy. 36) Support HW timestamping in mlx4 driver, from Amir Vadai. 37) Rationalize AF_PACKET packet timestamping when transmitting, from Willem de Bruijn and Daniel Borkmann. 38) Bring parity to what's provided by /proc/net/packet socket dumping and the info provided by netlink socket dumping of AF_PACKET sockets. From Nicolas Dichtel. 39) Fix peeking beyond zero sized SKBs in AF_UNIX, from Benjamin Poirier" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1722 commits) filter: fix va_list build error af_unix: fix a fatal race with bit fields bnx2x: Prevent memory leak when cnic is absent bnx2x: correct reading of speed capabilities net: sctp: attribute printl with __printf for gcc fmt checks netlink: kconfig: move mmap i/o into netlink kconfig netpoll: convert mutex into a semaphore netlink: Fix skb ref counting. net_sched: act_ipt forward compat with xtables mlx4_en: fix a build error on 32bit arches Revert "bnx2x: allow nvram test to run when device is down" bridge: avoid OOPS if root port not found drivers: net: cpsw: fix kernel warn on cpsw irq enable sh_eth: use random MAC address if no valid one supplied 3c509.c: call SET_NETDEV_DEV for all device types (ISA/ISAPnP/EISA) tg3: fix to append hardware time stamping flags unix/stream: fix peeking with an offset larger than data in queue unix/dgram: fix peeking with an offset larger than data in queue unix/dgram: peek beyond 0-sized skbs openvswitch: Remove unneeded ovs_netdev_get_ifindex() ...
2013-05-01Merge branch 'for-linus' of ↵Linus Torvalds6-73/+28
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull compat cleanup from Al Viro: "Mostly about syscall wrappers this time; there will be another pile with patches in the same general area from various people, but I'd rather push those after both that and vfs.git pile are in." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: syscalls.h: slightly reduce the jungles of macros get rid of union semop in sys_semctl(2) arguments make do_mremap() static sparc: no need to sign-extend in sync_file_range() wrapper ppc compat wrappers for add_key(2) and request_key(2) are pointless x86: trim sys_ia32.h x86: sys32_kill and sys32_mprotect are pointless get rid of compat_sys_semctl() and friends in case of ARCH_WANT_OLD_COMPAT_IPC merge compat sys_ipc instances consolidate compat lookup_dcookie() convert vmsplice to COMPAT_SYSCALL_DEFINE switch getrusage() to COMPAT_SYSCALL_DEFINE switch epoll_pwait to COMPAT_SYSCALL_DEFINE convert sendfile{,64} to COMPAT_SYSCALL_DEFINE switch signalfd{,4}() to COMPAT_SYSCALL_DEFINE make SYSCALL_DEFINE<n>-generated wrappers do asmlinkage_protect make HAVE_SYSCALL_WRAPPERS unconditional consolidate cond_syscall and SYSCALL_ALIAS declarations teach SYSCALL_DEFINE<n> how to deal with long long/unsigned long long get rid of duplicate logics in __SC_....[1-6] definitions
2013-05-01perf: Fix vmalloc ring buffer pages handlingJiri Olsa1-4/+10
If we allocate perf ring buffer with the size of single (user) page, we will get memory corruption when releasing itin rb_free_work function (for CONFIG_PERF_USE_VMALLOC option). For single page sized ring buffer the page_order is -1 (because nr_pages is 0). This needs to be recognized in the rb_free_work function to release proper amount of pages. Adding data_page_nr function that returns number of allocated data pages. Customizing the rest of the code to use it. Reported-by: Jan Stancek <jstancek@redhat.com> Original-patch-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/20130319143509.GA1128@krava.brq.redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-04-30Merge branch 'akpm' (incoming from Andrew)Linus Torvalds22-364/+600
Merge third batch of fixes from Andrew Morton: "Most of the rest. I still have two large patchsets against AIO and IPC, but they're a bit stuck behind other trees and I'm about to vanish for six days. - random fixlets - inotify - more of the MM queue - show_stack() cleanups - DMI update - kthread/workqueue things - compat cleanups - epoll udpates - binfmt updates - nilfs2 - hfs - hfsplus - ptrace - kmod - coredump - kexec - rbtree - pids - pidns - pps - semaphore tweaks - some w1 patches - relay updates - core Kconfig changes - sysrq tweaks" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (109 commits) Documentation/sysrq: fix inconstistent help message of sysrq key ethernet/emac/sysrq: fix inconstistent help message of sysrq key sparc/sysrq: fix inconstistent help message of sysrq key powerpc/xmon/sysrq: fix inconstistent help message of sysrq key ARM/etm/sysrq: fix inconstistent help message of sysrq key power/sysrq: fix inconstistent help message of sysrq key kgdb/sysrq: fix inconstistent help message of sysrq key lib/decompress.c: fix initconst notifier-error-inject: fix module names in Kconfig kernel/sys.c: make prctl(PR_SET_MM) generally available UAPI: remove empty Kbuild files menuconfig: print more info for symbol without prompts init/Kconfig: re-order CONFIG_EXPERT options to fix menuconfig display kconfig menu: move Virtualization drivers near other virtualization options Kconfig: consolidate CONFIG_DEBUG_STRICT_USER_COPY_CHECKS relay: use macro PAGE_ALIGN instead of FIX_SIZE kernel/relay.c: move FIX_SIZE macro into relay.c kernel/relay.c: remove unused function argument actor drivers/w1/slaves/w1_ds2760.c: fix the error handling in w1_ds2760_add_slave() drivers/w1/slaves/w1_ds2781.c: fix the error handling in w1_ds2781_add_slave() ...
2013-04-30power/sysrq: fix inconstistent help message of sysrq keyzhangwei(Jovi)1-1/+1
Currently help message of /proc/sysrq-trigger highlight its upper-case characters, like below: SysRq : HELP : loglevel(0-9) reBoot Crash terminate-all-tasks(E) memory-full-oom-kill(F) kill-all-tasks(I) ... this would confuse user trigger sysrq by upper-case character, which is inconsistent with the real lower-case character registed key. This inconsistent help message will also lead more confused when 26 upper-case letters put into use in future. This patch fix power off sysrq key: "poweroff(o)" Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kgdb/sysrq: fix inconstistent help message of sysrq keyzhangwei(Jovi)1-1/+1
Currently help message of /proc/sysrq-trigger highlight its upper-case characters, like below: SysRq : HELP : loglevel(0-9) reBoot Crash terminate-all-tasks(E) memory-full-oom-kill(F) kill-all-tasks(I) ... this would confuse user trigger sysrq by upper-case character, which is inconsistent with the real lower-case character registed key. This inconsistent help message will also lead more confused when 26 upper-case letters put into use in future. This patch fix kgdb sysrq key: "debug(g)" Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kernel/sys.c: make prctl(PR_SET_MM) generally availableAmnon Shiloh1-8/+2
The purpose of this patch is to allow privileged processes to set their own per-memory memory-region fields: start_code, end_code, start_data, end_data, start_brk, brk, start_stack, arg_start, arg_end, env_start, env_end. This functionality is needed by any application or package that needs to reconstruct Linux processes, that is, to start them in any way other than by means of an "execve()" from an executable file. This includes: 1. Restoring processes from a checkpoint-file (by all potential user-level checkpointing packages, not only CRIU's). 2. Restarting processes on another node after process migration. 3. Starting duplicated copies of a running process (for reliability and high-availablity). 4. Starting a process from an executable format that is not supported by Linux, thus requiring a "manual execve" by a user-level utility. 5. Similarly, starting a process from a networked and/or crypted executable that, for confidentiality, licensing or other reasons, may not be written to the local file-systems. The code that does that was already included in the Linux kernel by the CRIU group, in the form of "prctl(PR_SET_MM)", but prior to this was enclosed within their private "#ifdef CONFIG_CHECKPOINT_RESTORE", which is normally disabled. The patch removes those ifdefs. Signed-off-by: Amnon Shiloh <u3557@miso.sublimeip.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30relay: use macro PAGE_ALIGN instead of FIX_SIZEzhangwei(Jovi)1-4/+1
Macro FIX_SIZE is same as PAGE_ALIGN at present, so use PAGE_ALIGN instead. Thanks Andrew found this. Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kernel/relay.c: move FIX_SIZE macro into relay.czhangwei(Jovi)1-0/+3
It's better to place FIX_SIZE macro in relay.c, instead of relay.h Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kernel/relay.c: remove unused function argument actorzhangwei(Jovi)1-8/+4
Currently argument `actor' is never used in the relay reading path, so remove it. Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30semaphore: use `bool' type for semaphore_waiter's upliguang1-3/+3
Signed-off-by: liguang <lig.fnst@cn.fujitsu.com> Cc: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30semaphore: use unlikely() for down's timeoutliguang1-1/+1
Signed-off-by: liguang <lig.fnst@cn.fujitsu.com> Cc: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30pid_namespace.c/.h: simplify definesRaphael S.Carvalho2-5/+0
Move BITS_PER_PAGE from pid_namespace.c to pid_namespace.h, since we can simplify the define PID_MAP_ENTRIES by using the BITS_PER_PAGE. [akpm@linux-foundation.org: kernel/pid.c:54:1: warning: "BITS_PER_PAGE" redefined] Signed-off-by: Raphael S.Carvalho <raphael.scarv@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kernel/pid.c: improve flow of a loop inside alloc_pidmap.Raphael S. Carvalho1-2/+6
find_next_offset() searches for an available "cleaned bit" in the respective pid bitmap (page), so returns the offset if found, otherwise it returns a value equals to BITS_PER_PAGE. For example, suppose find_next_offset didn't find any available bit, so there's no purpose to call mk_pid (Wasteful Cpu Cycles). Therefore, I found it could be better to call mk_pid after the checking (offset < BITS_PER_PAGE) returned sucessfully! Another point: If (offset < BITS_PER_PAGE) results in a "failure", then mk_pid would be called again afterwards. [akpm@linux-foundation.org: simplify code] Signed-off-by: Raphael S. Carvalho <raphael.scarv@gmail.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Serge Hallyn <serge.hallyn@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kexec: Use min() and min_t() to simplify logicZhang Yanfei1-16/+8
Simplify the logic of variable assignments. [akpm@linux-foundation.org: replace min_t with min, remove unneeded casts] Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Reviewed-by: Simon Horman <horms@verge.net.au> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kexec: fix wrong types of some local variablesZhang Yanfei1-3/+3
The types of the following local variables: - ubytes/mbytes in kimage_load_crash_segment()/kimage_load_normal_segment() - r in vmcoreinfo_append_str() are wrong, so fix them. Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Simon Horman <horms@verge.net.au> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30coredump: only SIGKILL should interrupt the coredumping taskOleg Nesterov1-2/+4
There are 2 well known and ancient problems with coredump/signals, and a lot of related bug reports: - do_coredump() clears TIF_SIGPENDING but of course this can't help if, say, SIGCHLD comes after that. In this case the coredump can fail unexpectedly. See for example wait_for_dump_helper()->signal_pending() check but there are other reasons. - At the same time, dumping a huge core on the slow media can take a lot of time/resources and there is no way to kill the coredumping task reliably. In particular this is not oom_kill-friendly. This patch tries to fix the 1st problem, and makes the preparation for the next changes. We add the new SIGNAL_GROUP_COREDUMP flag set by zap_threads() to indicate that this process dumps the core. prepare_signal() checks this flag and nacks any signal except SIGKILL. Note that this check tries to be conservative, in the long term we should probably treat the SIGNAL_GROUP_EXIT case equally but this needs more discussion. See marc.info/?l=linux-kernel&m=120508897917439 Notes: - recalc_sigpending() doesn't check SIGNAL_GROUP_COREDUMP. The patch assumes that dump_write/etc paths should never call it, but we can change it as well. - There is another source of TIF_SIGPENDING, freezer. This will be addressed separately. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Tested-by: Mandeep Singh Baines <msb@chromium.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Neil Horman <nhorman@redhat.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Roland McGrath <roland@hack.frob.com> Cc: Tejun Heo <tj@kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kmod: remove call_usermodehelper_fns()Lucas De Marchi1-14/+17
This function suffers from not being able to determine if the cleanup is called in case it returns -ENOMEM. Nobody is using it anymore, so let's remove it. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Tejun Heo <tj@kernel.org> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kmod: split call to call_usermodehelper_fns()Lucas De Marchi1-2/+10
Use call_usermodehelper_setup() + call_usermodehelper_exec() instead of calling call_usermodehelper_fns(). In case the latter returns -ENOMEM the cleanup function may had not been called - in this case we would not free argv and module_name. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi> Cc: Oleg Nesterov <oleg@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Tejun Heo <tj@kernel.org> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30usermodehelper: export call_usermodehelper_exec() and ↵Lucas De Marchi1-33/+24
call_usermodehelper_setup() call_usermodehelper_setup() + call_usermodehelper_exec() need to be called instead of call_usermodehelper_fns() when the cleanup function needs to be called even when an ENOMEM error occurs. In this case using call_usermodehelper_fns() the user can't distinguish if the cleanup function was called or not. [akpm@linux-foundation.org: export call_usermodehelper_setup() to modules] Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: James Morris <james.l.morris@oracle.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Tejun Heo <tj@kernel.org> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30ptrace: add ability to retrieve signals without removing from a queue (v4)Andrey Vagin1-0/+80
This patch adds a new ptrace request PTRACE_PEEKSIGINFO. This request is used to retrieve information about pending signals starting with the specified sequence number. Siginfo_t structures are copied from the child into the buffer starting at "data". The argument "addr" is a pointer to struct ptrace_peeksiginfo_args. struct ptrace_peeksiginfo_args { u64 off; /* from which siginfo to start */ u32 flags; s32 nr; /* how may siginfos to take */ }; "nr" has type "s32", because ptrace() returns "long", which has 32 bits on i386 and a negative values is used for errors. Currently here is only one flag PTRACE_PEEKSIGINFO_SHARED for dumping signals from process-wide queue. If this flag is not set, signals are read from a per-thread queue. The request PTRACE_PEEKSIGINFO returns a number of dumped signals. If a signal with the specified sequence number doesn't exist, ptrace returns zero. The request returns an error, if no signal has been dumped. Errors: EINVAL - one or more specified flags are not supported or nr is negative EFAULT - buf or addr is outside your accessible address space. A result siginfo contains a kernel part of si_code which usually striped, but it's required for queuing the same siginfo back during restore of pending signals. This functionality is required for checkpointing pending signals. Pedro Alves suggested using it in "gdb" to peek at pending signals. gdb already uses PTRACE_GETSIGINFO to get the siginfo for the signal which was already dequeued. This functionality allows gdb to look at the pending signals which were not reported yet. The prototype of this code was developed by Oleg Nesterov. Signed-off-by: Andrew Vagin <avagin@openvz.org> Cc: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: David Howells <dhowells@redhat.com> Cc: Dave Jones <davej@redhat.com> Cc: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Pedro Alves <palves@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kernel/timer.c: move some non timer related syscalls to kernel/sys.cStephen Rothwell2-207/+212
Andrew Morton noted: akpm3:/usr/src/25> grep SYSCALL kernel/timer.c SYSCALL_DEFINE1(alarm, unsigned int, seconds) SYSCALL_DEFINE0(getpid) SYSCALL_DEFINE0(getppid) SYSCALL_DEFINE0(getuid) SYSCALL_DEFINE0(geteuid) SYSCALL_DEFINE0(getgid) SYSCALL_DEFINE0(getegid) SYSCALL_DEFINE0(gettid) SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info) COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info) Only one of those should be in kernel/timer.c. Who wrote this thing? [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kernel/timer.c: convert compat_sys_sysinfo to COMPAT_SYSCALL_DEFINEStephen Rothwell1-2/+1
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kernel/compat.c: make do_sysinfo() staticStephen Rothwell2-66/+69
The only use outside of kernel/timer.c was in kernel/compat.c, so move compat_sys_sysinfo() next to sys_sysinfo() in kernel/timer.c. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kernel/smp.c: cleanupsAndrew Morton1-45/+46
We sometimes use "struct call_single_data *data" and sometimes "struct call_single_data *csd". Use "csd" consistently. We sometimes use "struct call_function_data *data" and sometimes "struct call_function_data *cfd". Use "cfd" consistently. Also, avoid some 80-col layout tricks. Cc: Ingo Molnar <mingo@elte.hu> Cc: Jens Axboe <axboe@kernel.dk> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Shaohua Li <shli@fusionio.com> Cc: Shaohua Li <shli@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kernel/smp.c: remove 'priv' of call_single_dataliguang1-4/+2
The 'priv' field is redundant; we can pass data via 'info'. Signed-off-by: liguang <lig.fnst@cn.fujitsu.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kernel/smp.c: use '|=' for csd_lockliguang1-1/+1
csd_lock() uses assignment to data->flags rather than |=. That is not buggy at present because only one bit (CSD_FLAG_LOCK) is defined in call_single_data.flags. But it will become buggy if we later add another flag, so fix it now. Signed-off-by: liguang <lig.fnst@cn.fujitsu.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30workqueue: include workqueue info when printing debug dump of a worker taskTejun Heo4-1/+93
One of the problems that arise when converting dedicated custom threadpool to workqueue is that the shared worker pool used by workqueue anonimizes each worker making it more difficult to identify what the worker was doing on which target from the output of sysrq-t or debug dump from oops, BUG() and friends. This patch implements set_worker_desc() which can be called from any workqueue work function to set its description. When the worker task is dumped for whatever reason - sysrq-t, WARN, BUG, oops, lockdep assertion and so on - the description will be printed out together with the workqueue name and the worker function pointer. The printing side is implemented by print_worker_info() which is called from functions in task dump paths - sched_show_task() and dump_stack_print_info(). print_worker_info() can be safely called on any task in any state as long as the task struct itself is accessible. It uses probe_*() functions to access worker fields. It may print garbage if something went very wrong, but it wouldn't cause (another) oops. The description is currently limited to 24bytes including the terminating \0. worker->desc_valid and workder->desc[] are added and the 64 bytes marker which was already incorrect before adding the new fields is moved to the correct position. Here's an example dump with writeback updated to set the bdi name as worker desc. Hardware name: Bochs Modules linked in: Pid: 7, comm: kworker/u9:0 Not tainted 3.9.0-rc1-work+ #1 Workqueue: writeback bdi_writeback_workfn (flush-8:0) ffffffff820a3ab0 ffff88000f6e9cb8 ffffffff81c61845 ffff88000f6e9cf8 ffffffff8108f50f 0000000000000000 0000000000000000 ffff88000cde16b0 ffff88000cde1aa8 ffff88001ee19240 ffff88000f6e9fd8 ffff88000f6e9d08 Call Trace: [<ffffffff81c61845>] dump_stack+0x19/0x1b [<ffffffff8108f50f>] warn_slowpath_common+0x7f/0xc0 [<ffffffff8108f56a>] warn_slowpath_null+0x1a/0x20 [<ffffffff81200150>] bdi_writeback_workfn+0x2a0/0x3b0 ... Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Acked-by: Jan Kara <jack@suse.cz> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Dave Chinner <david@fromorbit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30kthread: implement probe_kthread_data()Tejun Heo1-0/+19
One of the problems that arise when converting dedicated custom threadpool to workqueue is that the shared worker pool used by workqueue anonimizes each worker making it more difficult to identify what the worker was doing on which target from the output of sysrq-t or debug dump from oops, BUG() and friends. For example, after writeback is converted to use workqueue instead of priviate thread pool, there's no easy to tell which backing device a writeback work item was working on at the time of task dump, which, according to our writeback brethren, is important in tracking down issues with a lot of mounted file systems on a lot of different devices. This patchset implements a way for a work function to mark its execution instance so that task dump of the worker task includes information to indicate what the work item was doing. An example WARN dump would look like the following. WARNING: at fs/fs-writeback.c:1015 bdi_writeback_workfn+0x2b4/0x3c0() Modules linked in: CPU: 0 Pid: 28 Comm: kworker/u18:0 Not tainted 3.9.0-rc1-work+ #24 Hardware name: empty empty/S3992, BIOS 080011 10/26/2007 Workqueue: writeback bdi_writeback_workfn (flush-8:16) ffffffff820a3a98 ffff88015b927cb8 ffffffff81c61855 ffff88015b927cf8 ffffffff8108f500 0000000000000000 ffff88007a171948 ffff88007a1716b0 ffff88015b49df00 ffff88015b8d3940 0000000000000000 ffff88015b927d08 Call Trace: [<ffffffff81c61855>] dump_stack+0x19/0x1b [<ffffffff8108f500>] warn_slowpath_common+0x70/0xa0 ... This patch: Implement probe_kthread_data() which returns kthread_data if accessible. The function is equivalent to kthread_data() except that the specified @task may not be a kthread or its vfork_done is already cleared rendering struct kthread inaccessible. In the former case, probe_kthread_data() may return any value. In the latter, NULL. This will be used to safely print debug information without affecting synchronization in the normal paths. Workqueue debug info printing on dump_stack() and friends will make use of it. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Acked-by: Jan Kara <jack@suse.cz> Cc: Dave Chinner <david@fromorbit.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30arc, print-fatal-signals: reduce duplicated informationVineet Gupta1-2/+1
After the recent generic debug info on dump_stack() and friends, arc is printing duplicate information on debug dumps. [ARCLinux]$ ./crash crash/50: potentially unexpected fatal signal 11. <-- [1] /sbin/crash, TGID 50 <-- [2] Pid: 50, comm: crash Not tainted 3.9.0-rc4+ #132 <-- [3] ... Remove them. [tj@kernel.org: updated patch desc] Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: David S. Miller <davem@davemloft.net> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30dump_stack: unify debug information printed by show_regs()Tejun Heo1-0/+16
show_regs() is inherently arch-dependent but it does make sense to print generic debug information and some archs already do albeit in slightly different forms. This patch introduces a generic function to print debug information from show_regs() so that different archs print out the same information and it's much easier to modify what's printed. show_regs_print_info() prints out the same debug info as dump_stack() does plus task and thread_info pointers. * Archs which didn't print debug info now do. alpha, arc, blackfin, c6x, cris, frv, h8300, hexagon, ia64, m32r, metag, microblaze, mn10300, openrisc, parisc, score, sh64, sparc, um, xtensa * Already prints debug info. Replaced with show_regs_print_info(). The printed information is superset of what used to be there. arm, arm64, avr32, mips, powerpc, sh32, tile, unicore32, x86 * s390 is special in that it used to print arch-specific information along with generic debug info. Heiko and Martin think that the arch-specific extra isn't worth keeping s390 specfic implementation. Converted to use the generic version. Note that now all archs print the debug info before actual register dumps. An example BUG() dump follows. kernel BUG at /work/os/work/kernel/workqueue.c:4841! invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #7 Hardware name: empty empty/S3992, BIOS 080011 10/26/2007 task: ffff88007c85e040 ti: ffff88007c860000 task.ti: ffff88007c860000 RIP: 0010:[<ffffffff8234a07e>] [<ffffffff8234a07e>] init_workqueues+0x4/0x6 RSP: 0000:ffff88007c861ec8 EFLAGS: 00010246 RAX: ffff88007c861fd8 RBX: ffffffff824466a8 RCX: 0000000000000001 RDX: 0000000000000046 RSI: 0000000000000001 RDI: ffffffff8234a07a RBP: ffff88007c861ec8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8234a07a R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88007dc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: ffff88015f7ff000 CR3: 00000000021f1000 CR4: 00000000000007f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: ffff88007c861ef8 ffffffff81000312 ffffffff824466a8 ffff88007c85e650 0000000000000003 0000000000000000 ffff88007c861f38 ffffffff82335e5d ffff88007c862080 ffffffff8223d8c0 ffff88007c862080 ffffffff81c47760 Call Trace: [<ffffffff81000312>] do_one_initcall+0x122/0x170 [<ffffffff82335e5d>] kernel_init_freeable+0x9b/0x1c8 [<ffffffff81c47760>] ? rest_init+0x140/0x140 [<ffffffff81c4776e>] kernel_init+0xe/0xf0 [<ffffffff81c6be9c>] ret_from_fork+0x7c/0xb0 [<ffffffff81c47760>] ? rest_init+0x140/0x140 ... v2: Typo fix in x86-32. v3: CPU number dropped from show_regs_print_info() as dump_stack_print_info() has been updated to print it. s390 specific implementation dropped as requested by s390 maintainers. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Sam Ravnborg <sam@ravnborg.org> Acked-by: Chris Metcalf <cmetcalf@tilera.com> [tile bits] Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon bits] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30dump_stack: implement arch-specific hardware description in task dumpsTejun Heo2-6/+26
x86 and ia64 can acquire extra hardware identification information from DMI and print it along with task dumps; however, the usage isn't consistent. * x86 show_regs() collects vendor, product and board strings and print them out with PID, comm and utsname. Some of the information is printed again later in the same dump. * warn_slowpath_common() explicitly accesses the DMI board and prints it out with "Hardware name:" label. This applies to both x86 and ia64 but is irrelevant on all other archs. * ia64 doesn't show DMI information on other non-WARN dumps. This patch introduces arch-specific hardware description used by dump_stack(). It can be set by calling dump_stack_set_arch_desc() during boot and, if exists, printed out in a separate line with "Hardware name:" label. dmi_set_dump_stack_arch_desc() is added which sets arch-specific description from DMI data. It uses dmi_ids_string[] which is set from dmi_present() used for DMI debug message. It is superset of the information x86 show_regs() is using. The function is called from x86 and ia64 boot code right after dmi_scan_machine(). This makes the explicit DMI handling in warn_slowpath_common() unnecessary. Removed. show_regs() isn't yet converted to use generic debug information printing and this patch doesn't remove the duplicate DMI handling in x86 show_regs(). The next patch will unify show_regs() handling and remove the duplication. An example WARN dump follows. WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505() Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #3 Hardware name: empty empty/S3992, BIOS 080011 10/26/2007 0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48 ffffffff8108f500 ffffffff82228240 0000000000000040 ffffffff8234a08e 0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58 Call Trace: [<ffffffff81c614dc>] dump_stack+0x19/0x1b [<ffffffff8108f500>] warn_slowpath_common+0x70/0xa0 [<ffffffff8108f54a>] warn_slowpath_null+0x1a/0x20 [<ffffffff8234a0c3>] init_workqueues+0x35/0x505 ... v2: Use the same string as the debug message from dmi_present() which also contains BIOS information. Move hardware name into its own line as warn_slowpath_common() did. This change was suggested by Bjorn Helgaas. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: David S. Miller <davem@davemloft.net> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30dump_stack: consolidate dump_stack() implementations and unify their behaviorsTejun Heo1-0/+18
Both dump_stack() and show_stack() are currently implemented by each architecture. show_stack(NULL, NULL) dumps the backtrace for the current task as does dump_stack(). On some archs, dump_stack() prints extra information - pid, utsname and so on - in addition to the backtrace while the two are identical on other archs. The usages in arch-independent code of the two functions indicate show_stack(NULL, NULL) should print out bare backtrace while dump_stack() is used for debugging purposes when something went wrong, so it does make sense to print additional information on the task which triggered dump_stack(). There's no reason to require archs to implement two separate but mostly identical functions. It leads to unnecessary subtle information. This patch expands the dummy fallback dump_stack() implementation in lib/dump_stack.c such that it prints out debug information (taken from x86) and invokes show_stack(NULL, NULL) and drops arch-specific dump_stack() implementations in all archs except blackfin. Blackfin's dump_stack() does something wonky that I don't understand. Debug information can be printed separately by calling dump_stack_print_info() so that arch-specific dump_stack() implementation can still emit the same debug information. This is used in blackfin. This patch brings the following behavior changes. * On some archs, an extra level in backtrace for show_stack() could be printed. This is because the top frame was determined in dump_stack() on those archs while generic dump_stack() can't do that reliably. It can be compensated by inlining dump_stack() but not sure whether that'd be necessary. * Most archs didn't use to print debug info on dump_stack(). They do now. An example WARN dump follows. WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505() Hardware name: empty Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #9 0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48 ffffffff8108f50f ffffffff82228240 0000000000000040 ffffffff8234a03c 0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58 Call Trace: [<ffffffff81c614dc>] dump_stack+0x19/0x1b [<ffffffff8108f50f>] warn_slowpath_common+0x7f/0xc0 [<ffffffff8108f56a>] warn_slowpath_null+0x1a/0x20 [<ffffffff8234a071>] init_workqueues+0x35/0x505 ... v2: CPU number added to the generic debug info as requested by s390 folks and dropped the s390 specific dump_stack(). This loses %ksp from the debug message which the maintainers think isn't important enough to keep the s390-specific dump_stack() implementation. dump_stack_print_info() is moved to kernel/printk.c from lib/dump_stack.c. Because linkage is per objecct file, dump_stack_print_info() living in the same lib file as generic dump_stack() means that archs which implement custom dump_stack() - at this point, only blackfin - can't use dump_stack_print_info() as that will bring in the generic version of dump_stack() too. v1 The v1 patch broke build on blackfin due to this issue. The build breakage was reported by Fengguang Wu. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [s390 bits] Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Sam Ravnborg <sam@ravnborg.org> Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon bits] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>