#pragma section-numbers on
#pragma keywords Linux, kernel, operating system, changes, changelog, file system, Linus Torvalds, open source, device drivers
#pragma description Summary of the changes and new features merged in the Linux kernel during the 4.2 development cycle

Linux 4.2 [https://lkml.org/lkml/2015/8/30/96 has been released] on 30 Aug 2015

/!\ /!\ Warning /!\ /!\ This page will be completed in the future (it will, really) 

= Prominent features =

= Drivers and architectures =
 All the driver and architecture-specific changes can be found in the [http://kernelnewbies.org/Linux_4.2-DriversArch Linux_4.2-DriversArch] page.
= Core (various) =
 * futex: Implement lockless wakeups. At the lowest level,it can reduce latency of a single thread attempting to acquire hb->lock in highly contended scenarios up to 2x  [https://git.kernel.org/torvalds/c/1d0dcb3ad9d336e6d6ee020a750a7f8d907e28de commit]
 * mqueue: Implement lockless pipelined wakeups [https://git.kernel.org/torvalds/c/fa6004ad4528153b699a4d5ce5ea6b33acce74cc commit]
 * Allow drivers request for their probe functions to be called asynchronously during driver and device registration (manual binding is still synchronous) [https://git.kernel.org/torvalds/c/765230b5f084863183aa8adb3405ab3f32c0b16e commit], [https://git.kernel.org/torvalds/c/f2411da746985e60d4d087f3a43e271c61785927 commit], [https://git.kernel.org/torvalds/c/d173a137c5bd95ee29d02705e5fa8890ef149718 commit]
 * printk: implement support for extended console drivers [https://git.kernel.org/torvalds/c/6fe29354befe4c46eb308b662155d4d8017358e1 commit]
 * rcu: Provide diagnostic option to slow down grace-period scans [https://git.kernel.org/torvalds/c/0f41c0ddadfb3d5baffe62351c380e2881aacd58 commit]
 * task scheduler
  * Replace spinlocks with atomics in thread_group_cputimer(), to improve scalability [https://git.kernel.org/torvalds/c/1018016c706f7ff9f56fde3a649789c47085a293 commit]
  * debug: Add sum_sleep_runtime to /proc/<pid>/sched when CONFIG_SCHEDSTATS is enabled [https://git.kernel.org/torvalds/c/82a0d2762699b95d6ce4114d00dc1865df9b0df3 commit]
  * debug: Replace vruntime with wait_sum in /proc/sched_debug [https://git.kernel.org/torvalds/c/c5f3ab1c3b2e277cca6462415038dab02b4ad396 commit]
  * numa: Show numa_group ID in /proc/sched_debug task listings to see how the numa groups have spread across the system [https://git.kernel.org/torvalds/c/e3d24d0a6048a826de5562d75dedb664d3a2a1b2 commit]
  * Implement lockless wake-queues API [https://git.kernel.org/torvalds/c/7675104990ed255b9315a82ae827ff312a2a88a2 commit]
 * Export the CPU list that actually got isolated in /sys/devices/system/cpu/isolated. This can be used by system management tools like libvirt, openstack, and others to ensure proper placement of tasks [https://git.kernel.org/torvalds/c/59f30abe94bff50636c8cad45207a01fdcb2ee49 commit]
 * Export the CPU list running in nohz_full mode in /sys/devices/system/cpu/nohz_full. This can be used by system management tools like libvirt, openstack, and others to ensure proper placement of tasks [https://git.kernel.org/torvalds/c/6570a9a1ce3a1dd227a065fd8ad16778d827b753 commit]
* Allow the watchdog to run by default only on the housekeeping cores when nohz_full is in effect; this seems to be a good compromise short of turning it off completely (since the nohz_full cores can't tolerate a watchdog). To provide customizability, a /proc/sys/kernel/watchdog_cpumask file is added so that the set of cores running the watchdog can be tuned to different values after bootup [https://git.kernel.org/torvalds/c/b5242e98c1cb834feb1e84026f09a4796b49eb4d commit], [https://git.kernel.org/torvalds/c/f51c0eaee39e306458d2bf8a30e010615fa451cc commit], [https://git.kernel.org/torvalds/c/fe4ba3c34352b7e8068b7f18eb233444aed17011 commit]


= File systems =
 * BTRFS
  * Let btree defrag work in SSD mode [https://git.kernel.org/torvalds/c/13028901a4a62096e97a0fc44388ea859587f690 commit]
  * Allow unprivileged query of the root id of the containing subvolume with the INO_LOOKUP ioctl [https://git.kernel.org/torvalds/c/01b810b889d557257580970e1a7ba9c85b54766b commit]
  * Show "subvol=" and "subvolid=" in /proc/mounts [https://git.kernel.org/torvalds/c/c8d3fe028f64054d75c72566efb9ecf3c75ee161 commit]

 * FUSE
  * Allow an open fuse device to be "cloned" with FUSE_DEV_IOC_CLONE ioctl  [https://git.kernel.org/torvalds/c/00c570f4ba43ae73b41fa0a2269c3b0ac20386ef commit]

 * CIFS
  * Add (minimal) support for the new protocol dialect, SMB3.1.1 [https://git.kernel.org/torvalds/c/aab1893d5fbeb7c931e97189f54a71ab0ecbf4c7 commit], [https://git.kernel.org/torvalds/c/eed0e1753cbe7a30758ad2ee5e2742dd7fda2c41 commit], [https://git.kernel.org/torvalds/c/ebb3a9d4ba3babd19c83b96fc88fc9b0d2f7d2d6 commit], [https://git.kernel.org/torvalds/c/5f7fbf733c9dd6b58d40fa394313a5949b696f84 commit]
  * Add reflink copy support (cp --reflink ) over SMB3.11 [https://git.kernel.org/torvalds/c/02b1666544c08e245cb4e2253ed575f8128943d6 commit]
  * Add ioctl CIFS_IOC_SET_INTEGRITY to set integrity. Set integrity increases reliability of files stored on SMB3 servers [https://git.kernel.org/torvalds/c/b3152e2c7aa9ad0c50085738d048fbf16d01d32d commit]
 * EXT2
  * Enable cgroup writeback support [https://git.kernel.org/torvalds/c/108dad65be9786650c78ed9aea28c9b4a68810d9 commit]
 * EXT4
  * Add support FALLOC_FL_INSERT_RANGE for [http://man7.org/linux/man-pages/man2/fallocate.2.html fallocate(2)], which allows to insert a hole within the file without overwriting any existing data [https://git.kernel.org/torvalds/c/331573febb6a224bc50322e3670da326cb7f4cfc commit]
 * F2FS
  * Support FALLOC_FL_ZERO_RANGE in [http://man7.org/linux/man-pages/man2/fallocate.2.html fallocate(2)], which zeroes a part of the file [https://git.kernel.org/torvalds/c/75cd4e098d178433436abce08146a21647bb4585 commit]
  * Support FALLOC_FL_COLLAPSE_RANGE in [http://man7.org/linux/man-pages/man2/fallocate.2.html fallocate(2)], which removes a range from a file, without leaving a hole [https://git.kernel.org/torvalds/c/b4ace33703243fed56f8bfc80a001533acb9decb commit]
  * Support FALLOC_FL_INSERT_RANGE in [http://man7.org/linux/man-pages/man2/fallocate.2.html fallocate(2)], which inserts a range in a file without overwritting data [https://git.kernel.org/torvalds/c/f62185d0e283e9d311e3ac1020f159d95f0aab39 commit]
  * Support RENAME_WHITEOUT in [http://man7.org/linux/man-pages/man2/rename.2.html renameat2(2)], used for for overlay/union filesystem implementations [https://git.kernel.org/torvalds/c/7e01e7ad746bc8198a8b46163ddc73a1c7d22339 commit]
  * Support encryption of f2fs files and directories [https://git.kernel.org/torvalds/c/fcc85a4d86b5018f08717160c89c0eb50afd1dca commit], [https://git.kernel.org/torvalds/c/0adda907f23df2e19355b58a20f0a7ff76587c6a commit], [https://git.kernel.org/torvalds/c/f424f664f0e8949361d268e2e91c7acc8cf63eb2 commit], [https://git.kernel.org/torvalds/c/4375a33664de17af9032b5f491a49bd256670927 commit], [https://git.kernel.org/torvalds/c/b93531dd7b9b39faace22abde2d5296e87b50499 commit], [https://git.kernel.org/torvalds/c/d33793fb89c2e3576d1f219e58f59365484f475e commit], [https://git.kernel.org/torvalds/c/57e5055b0a5e33267b8be366ee52ce5cdc239bc7 commit], [https://git.kernel.org/torvalds/c/9ea97163c6dad2430e06238acefe7a1d613629cf commit], [https://git.kernel.org/torvalds/c/6e22c691ba0a63ba89f516f0bf1828cf6dce372d commit], [https://git.kernel.org/torvalds/c/d8c6822a0556a88b13c8483599589752cf3e39f7 commit], [https://git.kernel.org/torvalds/c/e7d5545285ededcf73dc7cbb9b7c65d0259f2b44 commit], [https://git.kernel.org/torvalds/c/cbaf042a3cc6c37f9005fd6952cbf2013ab7cc15 commit], [https://git.kernel.org/torvalds/c/cde4de1205770514005663d70a9a7d81cb555085 commit], [https://git.kernel.org/torvalds/c/6b3bd08f93a849edd56595391a54100d607ad7e4 commit]
  * Add compat_ioctl to provide backward compatability [https://git.kernel.org/torvalds/c/08b95126c787441e4ef572422a5237dd985147be commit]
  * Add default mount options to remount [https://git.kernel.org/torvalds/c/498c5e9fcd10c89404601b222c1dbcb6e4f10a02 commit]
  * Recovers a broken superblock with the other valid one [https://git.kernel.org/torvalds/c/da554e48caab95a48afe0d7be8d9eae2bbdaa28d commit]

 * OVERLAYFS
  * Allow distributed filesystems as lower layer [https://git.kernel.org/torvalds/c/7c03b5d45b8eebf0111125053d8fe887cc262ba6 commit]

 * GFS2
  * Add support for rename2 and RENAME_EXCHANGE [https://git.kernel.org/torvalds/c/a63b7bbc2175901d79fa36ba734499655c077f0d commit]

 * NFS
  * NFSv4.2 LAYOUTSTATS functionality for pnfs flexfiles [https://git.kernel.org/torvalds/c/122d328d303afaa06ad530ca0b2e5be3cd50a1a5 (merge)]

 * NILFS2
  * Support NFSv2 export [https://git.kernel.org/torvalds/c/f73c2f1f83ca1c4e2f4515f987973bfe56c86973 commit]

 * UDF
  * Support NFSv2 export [https://git.kernel.org/torvalds/c/92acca45428f28c0b387f85b52b230d526dd0ecc commit]

 * FS-Cache
  * Count culled objects and objects rejected due to lack of space, and the number of initialised operations, and show them in /proc/fs/fscache/stats  [https://git.kernel.org/torvalds/c/03cdd0e4b9a98ae995b81cd8f58e992ec3f44ae2 commit], [https://git.kernel.org/torvalds/c/182d919b84902eece162c63ed3d476c8016b4197 commit]


= Memory management =
 * memcg: add per cgroup dirty page accounting, which provides the ability for each memory cgroup to have independent dirty/writeback page statistics which can provide information for per-cgroup direct reclaim or some. The new memcg stat is visible in the per memcg memory.stat cgroupfs file. The new accounting supports future efforts to add per cgroup dirty page throttling and writeback [https://git.kernel.org/torvalds/c/c4843a7593a9df3ff5b1806084cefdfa81dd7c79 commit]
 * Try to allocate all boot time kernel data structures from mirrored memory to have a recovery path for unrecoverable memory errors encountered during kernel code execution [https://git.kernel.org/torvalds/c/fc6daaf93151877748f8096af6b3fddb147f22d6 commit], [https://git.kernel.org/torvalds/c/a3f5bafcc04aaf62990e0cf3ced1cc6d8dc6fe95 commit], [https://git.kernel.org/torvalds/c/b05b9f5f9dcf593a0e9327676b78e6c17b4218e8 commit]


= Block layer =
 * The libnvdimm sub-system introduces, in addition to the libnvdimm-core, 4 drivers / enabling modules (common code to all: [https://git.kernel.org/torvalds/c/88793e5c774ec69351ef6b5200bb59f532e41bca (merge)])
  * NFIT: Add ACPI NVDIMM Firmware Interface Table (NFIT) support: It adds infrastructure to probe ACPI 6 compliant platforms for NVDIMMs (NFIT) and register a libnvdimm device tree. In addition to storage devices this also enables libnvdimm to pass ACPI._DSM messages for platform/dimm configuration.
  * PMEM:  Initially merged in v4.1 this driver for contiguous spans of persistent memory address ranges is re-worked to drive PMEM-namespaces emitted by the libnvdimm-core. In this update the PMEM driver, on x86, gains the ability to assert that writes to persistent memory have been flushed all the way through the caches and buffers in the platform to persistent media.
  * BLK: This new driver enables access to persistent memory media through "Block Data Windows" as defined by the NFIT.  The primary difference of this driver to PMEM is that only a small window of persistent memory is mapped into system address space at any given point in time. Per-NVDIMM windows are reprogrammed at run time, per-I/O, to access different portions of the media.  BLK-mode, by definition, does not support DAX
  * BTT: This is a library, optionally consumed by either PMEM or BLK, that converts a byte-accessible namespace into a disk with atomic sector update semantics (prevents sector tearing on crash or power loss)

 * Make CFQ default to IOPS mode on SSDs [https://git.kernel.org/torvalds/c/41c0126b3f22ef36b97b3c38b8f29569848a5ce2 commit]
 * Addition of policy specific data to blkcg for block cgroups  [https://git.kernel.org/torvalds/c/e48453c386f39ca9ea29e9df6efef78f56746af0 commit]
 * Add support for DAX reads/writes to block devices [https://git.kernel.org/torvalds/c/bbab37ddc20bae4709bca8745c128c4f46fe63c5 commit]
 * UBI: Dynamically allocate minor numbers [https://git.kernel.org/torvalds/c/2bf50d42f3a418153d2964ca0f25655177f36445 commit]
 * Device mapper
  * dm raid: Add dm-raid access to the MD RAID0 personality to enable single zone striping [https://git.kernel.org/torvalds/c/0cf4503174c12025ac7ea61048cb7c1d4d1ed85c commit]
  * dm cache: Add fail io mode and needs_check flag: If a cache metadata operation fails (e.g. transaction commit) the cache's metadata device will abort the current transaction, set a new needs_check flag, and the cache will transition to "read-only" mode [https://git.kernel.org/torvalds/c/028ae9f76f2935e8cf9974bff9a4587e3a995ff3 commit]
  * dm cache: add stochastic-multi-queue (smq) policy, make it default: The stochastic-multi-queue (smq) policy addresses some of the problems with the current multiqueue (mq) policy (memory usage, level balancing, adaptability, performance) [https://git.kernel.org/torvalds/c/66a636356647a9be8885c2ce2948de126577698a commit], [https://git.kernel.org/torvalds/c/bccab6a01afc26f53d91762d78153513cad10b29 commit]
  * dm stats: add support for request-based DM devices (eg. multipath) [https://git.kernel.org/torvalds/c/e262f34741522e0d821642e5449c6eeb512723fc commit]
  * dm stats: add option to dm statistics to collect and report a histogram of IO latencies [https://git.kernel.org/torvalds/c/dfcfac3e4cd94abef779297fab6adfd2dbcf52fa commit]
  * dm stats:  Make it possible to use precise timestamps with nanosecond granularity [https://git.kernel.org/torvalds/c/c96aec344de0de857ef3d7fba53992c7ba311e1e commit]
  * dm thin: range discard support [https://git.kernel.org/torvalds/c/34fbcf6257eb3f39a5b78a4f51b40f881b82033b commit]
 * rbd: queue_depth map option [https://git.kernel.org/torvalds/c/b55841807fb864eccca0167650a65722fd7cd553 commit]


= Cryptography =
 * Add jitterentropy RNG. The CPU Jitter RNG provides a source of good entropy by collecting CPU executing time jitter. The entropy in the CPU execution time jitter is magnified by the CPU Jitter Random Number Generator [https://git.kernel.org/torvalds/c/bb5530e4082446aac3a3d69780cd4dbfa4520013 commit]
 * drbg: use Jitter RNG to obtain seed [https://git.kernel.org/torvalds/c/b8ec5ba42c4a3854e27c44e697d9b4f0b84b32bb commit]
 * rng: Make DRBG the default crypto api RNG [https://git.kernel.org/torvalds/c/401e4238f35c7a21d32bc27370d4d045f7019c20 commit]
 * New chacha20 cipher. ChaCha20 is a 256-bit high-speed stream cipher [http://cr.yp.to/chacha/chacha-20080128.pdf designed by Daniel J.Bernstein] and further specified in RFC7539 for use in IETF protocols [https://git.kernel.org/torvalds/c/c08d0e647305c3f8f640010a56c9e4bafb9488d3 commit]
 * Add Poly1305 authenticator algorithm. Poly1305 is an authenticator algorithm designed by Daniel J. Bernstein, it is used for the ChaCha20-Poly1305 AEAD, specified in RFC7539 for use in IETF protocols  [https://git.kernel.org/torvalds/c/71ebc4d1b27d345342bdcb32a29c8cc3da8c6654 commit], [https://git.kernel.org/torvalds/c/4db4ad26096c4c1e579f9a957ca7752fe02bf7b4 commit], [https://git.kernel.org/torvalds/c/f979e014c50ce3f7467f133898dbea2243247a91 commit]
 * rsa: add a new rsa generic implementation [https://git.kernel.org/torvalds/c/cfc2bb32b31371d6bffc6bf2da3548f20ad48c83 commit]
 * Added support for SEC1 hardware to talitos [https://git.kernel.org/torvalds/c/21590888490ce2a46ff4703b1503f562f4a59571 commit], [https://git.kernel.org/torvalds/c/0635b7db143195281c5a29d272bb836be58af1d4 commit], [https://git.kernel.org/torvalds/c/2d02905ebd22c0271a25e424ab209c8b7067be67 commit], [https://git.kernel.org/torvalds/c/dd3c0987f5426d2df4a0c92de82dac65874bb9a4 commit], [https://git.kernel.org/torvalds/c/7d607c6a71f7a4905831fc2b1636e080533ab2db commit], [https://git.kernel.org/torvalds/c/5b841a65dcae3ac76dc34e56c948c629de48c1a3 commit], [https://git.kernel.org/torvalds/c/90490752eb03ddc1015233034ec26816f0ea0de3 commit], [https://git.kernel.org/torvalds/c/922f9dc8d36651abea51c4f2ff9c08ba4db692ff commit], [https://git.kernel.org/torvalds/c/6f65f6ac5fb36a90ebf9a8d57cc4076b82d5009e commit], [https://git.kernel.org/torvalds/c/04a34d4680e75e9be63204b3a7b51a6abe3ce35a commit]
 * echainiv: Add Encrypted Chain IV Generator, which generates an IV based on the encryption of a sequence number xored with a salt.  This is the default algorithm for CBC [https://git.kernel.org/torvalds/c/a10f554fa7e09ad236cfa0bdabaf6549c0b073a4 commit]
 * seqiv: Add a new IV generator seqniv which is identical to seqiv except that it skips the IV when authenticating.  This is intended to be used by algorithms such as rfc4106 that does the IV authentication implicitly [https://git.kernel.org/torvalds/c/3c08fee7b5ce471a7114478ac8c6e546787bd8c2 commit]

= Security =
 * selinux: enable genfscon labeling for sysfs and pstore files [https://git.kernel.org/torvalds/c/8e01472078763ebc1eaea089a1adab75dd982ccd commit]
 * selinux: enable per-file labeling for debugfs files. [https://git.kernel.org/torvalds/c/134509d54e4e98888be2697a92cb4b48957b792b commit]
 * Smack: allow multiple labels in onlycap [https://git.kernel.org/torvalds/c/c0d77c884461fc0dec0411e49797dc3f3651c31b commit]
 * evm: permit the labeling of existing files on pseudo files systems [https://git.kernel.org/torvalds/c/5101a1850bb7ccbf107929dee9af0cd2f400940f commit]
 * ima: add support for new "euid" policy condition [https://git.kernel.org/torvalds/c/139069eff7388407f19794384c42a534d618ccd7 commit]
 * ima: extend "mask" policy matching support [https://git.kernel.org/torvalds/c/4351c294b8c1028077280f761e158d167b592974 commit]
 * ima: update builtin policies [https://git.kernel.org/torvalds/c/24fd03c87695a76f0517df42a37e51b1597d2c8a commit]


= Tracing and perf tool =
 * Allow disabling/enabling events dynamically in 'perf top': a 'perf top' session can instantly become a 'perf report' one, i.e. going from dynamic analysis to a static one, returning to a dynamic one is possible, to toogle the modes, just press 'f' to 'freeze/unfreeze' the sampling [https://git.kernel.org/torvalds/c/5d484f99aed547e235f2229653c95392a1bc3692 commit], [https://git.kernel.org/torvalds/c/fbb7997e308064a0ea26fb5435ee5fa69a588dac commit]
 * Add Instruction Tracing support (--itrace) [https://git.kernel.org/torvalds/c/0f0aa5e0693ce4000a7657cc47ce4f32b86b91ba commit], [https://git.kernel.org/torvalds/c/e9db1310d95c9d02763643108d51e47d9eb79ac9 commit], [https://git.kernel.org/torvalds/c/7a680eb990b6646ecadf22dca7ded16a33f731b9 commit], [https://git.kernel.org/torvalds/c/520a2ebc2f0bd46b65feb7ca73a9ed65ea1a36bd commit], [https://git.kernel.org/torvalds/c/53c76b0e9ed5ed1f00371160f0be60402acba165 commit]
 * perf probe: Accept multiple filter options. Each filters are combined by logical-or. E.g. --filter abc* --filter *def is same as --filter abc*|*def [https://git.kernel.org/torvalds/c/96b55e39237b8bc92d8e6b96f896c106f2d39cf6 commit]
 * perf kmem: Add --live option for current allocation stat [https://git.kernel.org/torvalds/c/2a7ef02c9ca0172cd48945407893f38c2438e754 commit]
 * perf kmem: Add kmem.default config option to select the default value ('page' or 'slab')  [https://git.kernel.org/torvalds/c/0c160d495b5616e071bb4f873812e8f473128149 commit]
 * perf kmem: Implement stat --page --caller, it shows caller statistics for page [https://git.kernel.org/torvalds/c/c9758cc4569955c6d8ad519adf539848e8824c72 commit]
 * perf kmem: Add new sort keys for page: page, order, migtype, gfp [https://git.kernel.org/torvalds/c/fb4f313d304b0a5120e870a6cd9ecf90c1023037 commit]
 * perf probe: allows the user to pass the filter pattern directly to the --funcs option [https://git.kernel.org/torvalds/c/9f7811d08dcf7b3e900cbc0d8384b713a86b034f commit] and --list option [https://git.kernel.org/torvalds/c/b6a896438b3275df434a8f99bee58292b31693bd commit] and --del option [https://git.kernel.org/torvalds/c/307a464b2342a502da492f0ada8cefd6ab7f63a7 commit]
 * perf record: Add AUX area tracing Snapshot Mode support (--snapshot) [https://git.kernel.org/torvalds/c/2dd6d8a10a942c5fd8950d1046e172237d009c8e commit], [https://git.kernel.org/torvalds/c/d20031bb63dd6dde35feb7845eaf17c620eef120 commit]
 * perf bench futex: A new benchmark 'wake-parallel' is added to measure parallel waker threads [https://git.kernel.org/torvalds/c/d65817b4e707068c2dd3e002e87c2a0294aabc2c commit]
 * perf probe: Add --no-inlines option to avoid searching inline functions [https://git.kernel.org/torvalds/c/6cfd1f6805ca0b4a341794d67eb605089435f938 commit]
 * perf probe: Support $params special probe argument. $params is similar to $vars but matches only function parameters not local variables. Thus, this is useful for tracing function parameter changing or tracing function call with parameters [https://git.kernel.org/torvalds/c/f8bffbf1222a64336a81974fc25fe846656ac53e commit]
 * perf probe: Support glob wildcards for function name when adding new probes. This will allow us to build caches of function-entry level information with $params [https://git.kernel.org/torvalds/c/4c859351226c920b227fec040a3b447f0d482af3 commit]
 * perf probe: Add --range option to show a variable's location range [https://git.kernel.org/torvalds/c/349e8d2611316cce11c0b9d0830ebb585c9b82b8 commit]
 * perf sched: Add option to merge like comms to lat output [https://git.kernel.org/torvalds/c/2f80dd4488c204a4850554746eb31f25f5a84405 commit]
 * perf record: Add a new branch sampling type support for indirect jumps: perf record -j ind_jmp .......It enables analysis of indirect jumps targets [https://git.kernel.org/torvalds/c/5b68164d6a1fdbe02b30bd777d1f686c6d901f28 commit]
 * perf tools: Make Ctrl-C stop processing on TUI [https://git.kernel.org/torvalds/c/ed426915900db3c58c410b8b38f6ff0e46bf6c96 commit]
 * perf annotate: Display total number of samples with --show-total-period [https://git.kernel.org/torvalds/c/0c4a5bcea4609948375173cdea8d73783110a75e commit]
 * perf probe: Speed up perf probe --list by caching debuginfo [https://git.kernel.org/torvalds/c/7737af010b097f3c1e2aeded21774d58b4aa2698 commit]
 * perf tools: The time out to limit the individual proc map processing was hard code to 500ms. This patch introduce a new option --proc-map-timeout to make the time limit configurable [https://git.kernel.org/torvalds/c/9d9cad763ca79dd3697e9f2d1df648e37496582b commit]
 * perf stat: Currently all the -p option PID arguments tasks values get aggregated and printed as single values. Adding --per-tasks option to print values per task [https://git.kernel.org/torvalds/c/32b8af82e3708bc19af75c31fa773a98449f0edc commit]


 * BPF
  * BPF based latency tracing [https://git.kernel.org/torvalds/c/0fb1170ee68a6aa14eca0666e02c4b62cbf1251d commit]
  * Allow BPF programs access skb->skb_iif and skb->dev->ifindex fields [https://git.kernel.org/torvalds/c/37e82c2f974b72c9ab49c787ef7b5bb1aec12768 commit]
  * Allow bpf programs to tail-call other bpf programs [https://git.kernel.org/torvalds/c/04fd61ab36ec065e194ab5e74ae34a5240d992bb commit]
  * Allow programs to write to certain skb fields [https://git.kernel.org/torvalds/c/d691f9e8d4405c334aa10d556e73c8bf44cb0e01 commit]
  * Disallow bpf tc programs access current->pid,uid [https://git.kernel.org/torvalds/c/89d256bb69f2596c3a31ac51466eac9e1791c388 commit]
 * tracing: add trace event for memory-failure [https://git.kernel.org/torvalds/c/97f0b13452198290799fd6780f05fbaa74f927d3 commit]


= Virtualization =
 * KVM
  * Implement multiple address spaces [https://git.kernel.org/torvalds/c/f481b069e674378758c73761827e83ab05c46b52 commit]

 * Hyper-V
  * file copy service: full handshake support [https://git.kernel.org/torvalds/c/a4d1ee5b0255a135fead1d62a7fc7e6fe718b66e commit]
  * vmbus: Implement NUMA aware CPU affinity for channels [https://git.kernel.org/torvalds/c/1f656ff3fdddc2f59649cc84b633b799908f1f7b commit]
  * vmbus: Implement the protocol for tearing down vmbus state [https://git.kernel.org/torvalds/c/2db84eff127e3f4b3635edc589cd6a56db8755a3 commit]
  * vss: full handshake support [https://git.kernel.org/torvalds/c/cd8dc0548511efff7a97d978f989ce67a883f9a5 commit]
  * Tools: kvp: use misc char device to communicate with kernel [https://git.kernel.org/torvalds/c/8ddca8088586303cfe3db4209a4682f7a4cf7d2d commit], vss: use misc char device to communicate with kernel [https://git.kernel.org/torvalds/c/f5722b9bd418e29b7429bd9a43bd100599b26d4f commit]

= Networking =
 * TCP: Add CAIA Delay-Gradient (CDG) congestion control. CDG modifies the TCP sender in order to: -Use the delay gradient as a congestion signal; -Back off with an average probability that is independent of the RTT; - Coexist with flows that use loss-based congestion control, i.e., flows that are unresponsive to the delay signal; Tolerate packet loss unrelated to congestion.(disabled by default. Its FreeBSD implementation [http://www.ietf.org/proceedings/84/iccrg.html was presented for the ICCRG] in July 2012 [https://git.kernel.org/torvalds/c/2b0a8c9eee81882fc0001ccf6d9af62cdc682f9e commit]
 * Add IP_BIND_ADDRESS_NO_PORT to overcome bind(0) limitations: When an application needs to force a source IP on an active TCP socket it has to use bind(IP, port=x). As most applications do not want to deal with already used ports, x is often set to 0, meaning the kernel is in charge to find an available port. But kernel does not know yet if this socket is going to be a listener or be connected. This patch adds a new SOL_IP socket option, asking kernel to ignore the 0 port provided by application in bind(IP, port=0) and only remember the given IP address.  The port will be automatically chosen at connect() time, in a way that allows sharing a source port as long as the 4-tuples are unique  [https://git.kernel.org/torvalds/c/90c337da1524863838658078ec34241f45d8394d commit]
 * Introduce programable flow dissector [https://git.kernel.org/torvalds/c/fbff949e3bc7f3f7d9e8b3ef4855ec7138276a25 commit]
 * Introduce Flower classifier, which can classify packets based on a configurable combination of packet keys and masks [https://git.kernel.org/torvalds/c/77b9900ef53ae047e36a37d13a2aa33bb2d60641 commit]
 * TCP: Add rfc3168, section 6.1.1.1. fallback for outgoing ECN connections. In other words, this work adds a retry with a non-ECN setup SYN packet, as suggested from the RFC on the first timeout. For users explicitly not wanting this which can be in DC use case, a net.ipv4.tcp_ecn_fallback knob is added that allows for disabling the fallback [https://git.kernel.org/torvalds/c/492135557dc090a1abb2cfbe1a412757e3ed68ab commit]
 * switchdev: Add VLAN dump support to switchdev port's bridge_getlink.  iproute2 "bridge vlan show" cmd already knows how to show the vlans installed on the bridge and the device , but (until now) no one implemented the port vlan part of the netlink message [https://git.kernel.org/torvalds/c/06baa3d0fb8491b21d579d3220569730c01efacc (merge)]
 * Add a netdev driver for GENEVE (GEneric NEtwork Virtualization Encapsulation) tunnels. It allows one to create geneve virtual interfaces that provide Layer 2 Networks over Layer 3 Networks. GENEVE is often used to tunnel virtual network infrastructure in virtualized environments. For more information see http://tools.ietf.org/html/draft-gross-geneve-02 [https://git.kernel.org/torvalds/c/59af132bb68860de035388dcb531ac4ef46ccfa5 (merge)]
 * ieee802154: adds transmission power setting support for IEEE-802.15.4 devices via nl802154 [https://git.kernel.org/torvalds/c/0f999b09f5c1b135e840501840dbcd01fad66f79 commit]
 * Export the value of the linkdown sysctl to netconf [https://git.kernel.org/torvalds/c/974d7af5fcc295dcf8315255142b2fe44fd74b0c commit]
 * IPv6: IPv6 flow labels have been an unmitigated disappointment thus far. Support in HW devices to use them for ECMP is lacking, and OSes don't turn them on by default. This release splits the flow label space into two ranges: 0-7ffff is reserved for flow label manager, 80000-fffff will be used for creating auto flow labels (per RFC6438). This should give Linux a path to enabling auto flow labels by default for all IPv6 packets. It can be disabled with sysctl flowlabel_state_ranges [https://git.kernel.org/torvalds/c/82a584b7cd366511a22e37675b029cf2fb58e291 commit]
 * RDS
  * Add getsockopt/setsockopt support for SO_RDS_TRANSPORT [https://git.kernel.org/torvalds/c/8ba38460f363e4d26d666aae9bc7fd3afa5f8e43 commit], [https://git.kernel.org/torvalds/c/d97dac54bf83b2a3df85fba37595e355627e0f2b commit]
 * unix sockets
  * Support SCM_SECURITY for stream sockets [https://git.kernel.org/torvalds/c/37a9a8df8ce9de6ea73349c9ac8bdf6ba4ec4f70 commit]
  * Implement splice for stream af_unix sockets [https://git.kernel.org/torvalds/c/2b514574f7e88c8498027ee366fd6e7aae5aa4b5 commit]
  * Implement stream sendpage support [https://git.kernel.org/torvalds/c/869e7c62486ec0e170a9771acaa251d1a33b5871 commit]
 * IPv4: sysctl option (ignore_routes_with_linkdown) to ignore routes when nexthop link is down [https://git.kernel.org/torvalds/c/0eeb075fad736fb92620af995c47c204bbb5e829 commit]
 * net scheduler: run ingress qdisc without locks [https://git.kernel.org/torvalds/c/087c1a601ad7f851a2d31f5fa0e5e9dfc766df55 commit]
 * net scheduler :gred: Add a TCA_GRED_LIMIT attribute to set the GRED queue limit, in bytes, during qdisc setup [https://git.kernel.org/torvalds/c/a3eb95f891d6130b1fc03dd07a8b54cf0a5c8ab8 commit]
 * Implement extended console support [https://git.kernel.org/torvalds/c/e2f15f9a79201ddd596727b84a85c419ee57ad5c commit]
 * packet: add rollover statistics [https://git.kernel.org/torvalds/c/a9b6391814d5d6b8668fca2dace86949b7244e2e commit]
 * vlan: Add GRO support for non hardware accelerated vlan [https://git.kernel.org/torvalds/c/66e5133f19e901a044fa5eaeeb6ecff4545839e5 commit]
 * netfilter
  * Add netfilter ingress hook, this allows to classify packets from ingress using the Netfilter infrastructure [https://git.kernel.org/torvalds/c/e687ad60af09010936bbd0b2a3b5d90a8ee8353c commit]
  * nf_tables: add netdev table. It allows to create netdev tables that contain ingress chains. It provides access to the existing nf_tables features from the ingress hook [https://git.kernel.org/torvalds/c/ed6c4136f1571bd6ab362afc3410905a8a69ca42 commit]
  * xt_MARK: Add ARP support [https://git.kernel.org/torvalds/c/12b7ed29bdea2d6dde58f304321d4e8ca453f13c commit]
 * nl802154
  * Add support for dumping information about the current cca ed level [https://git.kernel.org/torvalds/c/e4390592a4fc3ee10a8bc4742197fdbac3935f74 commit]
  * Add support for dump phy capabilities [https://git.kernel.org/torvalds/c/0e66545701014814360b08a7a43ca652f82b6e5a commit]
  * Add support to set the cca ed level [https://git.kernel.org/torvalds/c/b69644c1c72e179738dd5c7e52e99d8550189472 commit]
 * openvswitch:  If new optional attribute OVS_USERSPACE_ATTR_ACTIONS is added to an OVS_ACTION_ATTR_USERSPACE action, then include the datapath actions
    in the upcall to userspace [https://git.kernel.org/torvalds/c/ccea74457bbdafe33dce8bffcb5cb183aeb5f2bb commit]
 * pktgen: introduce xmit_mode '<start_xmit|netif_receive>' [https://git.kernel.org/torvalds/c/62f64aed622b6055b5fc447e3e421c9351563fc8 commit], add benchmark script pktgen_bench_xmit_mode_netif_receive.sh [https://git.kernel.org/torvalds/c/05a14d5e17c21817946b6a50140c4a45257ad592 commit], add sample script pktgen_sample01_simple.sh [https://git.kernel.org/torvalds/c/6f09479758be247fef02188a275383ebaddbe291 commit], add sample script pktgen_sample02_multiqueue.sh [https://git.kernel.org/torvalds/c/282fb58947e129dea8badf48972ea89d027a76dc commit], add sample script pktgen_sample03_burst_single_flow.sh [https://git.kernel.org/torvalds/c/1d73ba16ad3975a2eb27e47e52fc215c0c5b8d83 commit], 
 * tipc: add broadcast link window set/get to nl api [https://git.kernel.org/torvalds/c/670f4f8818ee54d0c1831e3165dadd5b8a3f713e commit]
 * tipc: improve link congestion algorithm [https://git.kernel.org/torvalds/c/f21e897eccb5a236f4191ecc1b4391eda895d6ed commit]


 * bonding
  * Add netlink support for sys prio, actor sys mac, and port key, until now they were only exported via bond's proc entry [https://git.kernel.org/torvalds/c/171a42c38c6e1a5a076d6276e94e55a0b5b7868c commit]
  * Allow userspace to set actors' macaddr in an AD-system. [https://git.kernel.org/torvalds/c/74514957552edd4661a4608618121f3c71d4e891 commit]
  * Allow userspace to set actors' system_priority in AD system [https://git.kernel.org/torvalds/c/6791e4661c4bd3e9f193a84247f2c389578a4336 commit]
  * Implement user key part of port_key in an AD system. [https://git.kernel.org/torvalds/c/d22a5fc0c32edcf5c3bb973ee8c9a2606ba500a8 commit]
 * bridge: allow setting hash_max + multicast_router if interface is down [https://git.kernel.org/torvalds/c/6ae4ae8e512bd229f806c22f8a2cd751e4f987c2 commit]
 * Adds an optional ce_threshold to codel & fq_codel qdiscs, so that DCTCP can have feedback from queuing in the host [https://git.kernel.org/torvalds/c/80ba92fa1a92dea128283f69f55b02242e213650 commit]
 * Add TCPWinProbe and TCPKeepAlive SNMP counters [https://git.kernel.org/torvalds/c/e520af48c7e5acae5f17f82a79ba7ab7cf156f3b commit]


 * wireless
  * Add TX fastpath: add a "fast-xmit" cache that will cache the data frame 802.11 header and other data to be able to build the frame more quickly [https://git.kernel.org/torvalds/c/17c18bf880b2464851e5a2bca86521affc46c97e commit], [https://git.kernel.org/torvalds/c/e495c24731a2651fc2c1c7feedc8ba3b31f6b5d4 commit], [https://git.kernel.org/torvalds/c/3ffd884012bb12d3ed64c9fd9a142a62fdcfaf11 commit], [https://git.kernel.org/torvalds/c/725b812c839643639d6135b1f7fb41e48de465a4 commit], [https://git.kernel.org/torvalds/c/2d981fddb0e4a5a4097d926f3b9fd3eaf25867a8 commit], [https://git.kernel.org/torvalds/c/680a0daba74fed0bf30530c9b3e7e706cf29855f commit], [https://git.kernel.org/torvalds/c/80616c0db8a26f030be78fea39f7c880c4263e55 commit]
  * cfg80211: allow the plink state blocking for user managed mesh [https://git.kernel.org/torvalds/c/4292504044a4fd4c5d9155dcb5c7b09ed6cbf611 commit]

 * Bluetooth
  * hci_core/mgmt: Introduce multi-adv list [https://git.kernel.org/torvalds/c/d2609b345ebf0547015a78588c4d7ad68c9ccf26 commit]
  * mgmt: program multi-adv on power on [https://git.kernel.org/torvalds/c/320b3bf7027b89821030e5e7c5fbd1f6aecb4af0 commit]
 * NFC: netlink: Implement vendor-specific command support [https://git.kernel.org/torvalds/c/9e58095f9660f88d6a2febe87d5073a6b2e9c399 commit]


= List of merges =

= Other news sites =
 * LWN merge window [https://lwn.net/Articles/648995/ part 1], [https://lwn.net/Articles/649652/ part 2], [https://lwn.net/Articles/650299/ part 3]