Linux 4.10 Release - Main Changes, ARM & MIPS Architectures

Linus Torvalds has just released Linux 4.10:

So there it is, the final 4.10 release. It’s been quiet since rc8, but we did end up fixing several small issues, so the extra week was all good.

On the whole, 4.10 didn’t end up as small as it initially looked. After the huge release that was 4.9, I expected things to be pretty quiet, but it ended up very much a fairly average release by modern kernel standards. So we have about 13,000 commits (not counting merges – that would be another 1200+ commits if you count those). The work is all over, obviously – the shortlog below is just the changes in the last week, since rc8.

Go out and verify that it’s all good, and I’ll obviously start pulling stuff for 4.11 on Monday. Linus

Linux 4.9 added Greybus staging support, improved security thanks to virtually mapped kernel stacks, and memory protection keys, included various file systems improvements, and many more changes.

Some newsworthy changes for Linux 4.10 include:

Virtual GPU support – Intel GVT-g for KVM (KVMGT) is a full GPU virtualization solution with mediated pass-through, starting from 4th generation Intel Core processors with Intel Graphics. Unlike direct pass-through alternatives, the mediated device framework allows KVMGT to offer a complete virtualized GPU with full GPU features to each one of the virtualized guests, with part of performance critical resources directly assigned, while still having performance close to native.
New ‘perf c2c’ tool, for cacheline contention analysis – perf c2c (for “cache to cache”) is a new tool designed to analyse and track down performance problems caused by false sharing on NUMA systems. The tool is based on x86’s load latency and precise store facility events provided by Intel CPUs. Visit C2C – False Sharing Detection in Linux Perf for more details about the tool.
Improved writeback management – Linux 4.10 release adds a mechanism that throttles back buffered writeback, which makes more difficult for heavy writers to monopolize the I/O requests queue, and thus provides a smoother experience in Linux desktops and shells than what people was used to. The algorithm for when to throttle can monitor the latencies of requests, and shrinks or grows the request queue depth accordingly, which means that it’s auto-tunable, and generally, a user would not have to touch the settings. Read Toward less-annoying background writeback for more details about this improvement.
FAILFAST support – This release also adds “failfast” support. RAID disk with failed IOs are marked as broken quickly, and avoided in the future, which can improve latency.
Faster Initial WiFi Connection – Linux 4.10 adds support for using drivers with Fast Initial Link Setup as defined in IEEE 802.11ai. It enables a wireless LAN client to achieve a secure link setup within 100ms. This release covers only the FILS authentication/association functionality from IEEE 802.11ai, i.e., the other changes like scanning optimizations are not included.

Some notable ARM architecture improvements and new features:

Allwinner:
- Allwinner A23 – Audio codec driver
- Allwinner A31/A31s – Display Driver (first pipeline), audio codec support
- Allwinner A64 – clock driver
- Allwinner A80 – External SDIO WiFi
- Allwinner H3 – Audio codec driver, SPI
- New boards support: NextThingCo CHIP Pro, Pine A64, NanoPi M1

Rockchip:
- Initial support for Rockchip PX5 & PX3 automotive platforms
- Added Rockchip RK1108 evaluation board
- Added support for Rikomagic MK808 Android TV stick based on Rockchip RK3066
- Update Rockchip PCI driver to support for max-link-speed
- Rockchip rk3399,rk3066 PLL clock optimizations

Amlogic
- Support for the pre-release “SCPI” firmware protocol shipped by Amlogic in their GXBB SoC
- Initial support for Amlogic S905D, and S912 (GXM) SoCs
- Added support for Nexbox A1 and A95X Android TV boxes
- Cleanup for the Amlogic Meson PWM driver
- New Amlogic Meson Graphic Controller GXBB (S905)/GXL (S905X/S905D)/GXM (S912) SoCs (meson)
- Resets for 2nd USB PHY
- Initial support for the SD/eMMC controller in the Amlogic S905/GX* family of SoCs
- Updated DTS to enable support for USB, I2C, SPI, maibox/MHU, PWM, ethernet MAC & PHY, secure monitor, IR, and watchdog.
Samsung
- Device Tree for Samsung Exynos5433 mobile phone platform, including an (almost) fully supported phone reference board
- Added support for TOPEET itop/elite board based on exynos4412
- DeviceTree updates:
  - Add Performance Monitor Unit to Exynos7.
  - Add MFC, JPEG and Gscaler to Exynos5433 based TM2 board.
  - Cleanups and fixes for recently added TM2 and TM2E boards.
  - Enable ADC on Odroid boards
  - Remove unused Exynos4415 DTSI
Qualcomm
- Add support for Qualcomm MSM8992 (Snapdragon 808) and MSM8994 (Snapdragon 810) mobile phone SoCs
- Added support for Huawei Nexus 6P (Angler) and LG Nexus 5X (Bullhead) smartphones
- Support for Qualcomm MDM9615 LTE baseband
- Support for WP8548 MangOH Open Hardware platform for IOT, based on Qualcomm MDM9615
- Other device tree changes:
  - Added SDHC xo clk and 1.8V DDR support
  - Add EBI2 support to MSM8660
  - Add SMSC ethernet support to APQ8060
  - Add support for display, pstore, iommu, and hdmi to APQ8064
  - Add SDHCI node to MSM8974 Hammerhead
  - Add Hexagon SMD/PIL nodes
  - Add DB820c PMIC pins
  - Fixup APQ8016 voltage ranges
  - Add various MSM8996 nodes to support SMD/SMEM/SMP2P
Mediatek
- Added clock for Mediatek MT2701 SoCs
- New Mediatek drivers: mtk-mdp and mtk-vcodec (VP8/VP9/H.264) for MT8173
- Updated the Mediatek IOMMU driver to use the new struct device->iommu_fwspec member
Other new ARM hardware platforms and SoCs:
- Hisilicon – Hip07 server platform and D05 board
- NXP – LS1046A Communication processor, i.MX 6ULL SoC, UDOO Neo board, Boundary Devices Nitrogen6_SOM2 (i.MX6), Engicam i.CoreM6, Grinn i.MX6UL liteSOM/liteBoard, Toradex Colibri iMX6 module
- Nvidia – Early support for the Nvidia Tegra Tegra186 SoC, NVIDIA P2771 board, and NVIDIA P3310 processor module
- Marvell – Globalscale Marvell ESPRESSOBin community board based on Armada 3700, Turris Omnia open source hardware router based on Armada 385
- Renesas “R-Car Starter Kit Pro” (M3ULCB) low-cost automotive board, Renesas RZ/G (r8a7743 and r8a7745) application processors
- Oxford semiconductor (now Broadcom) OX820 SoC for NAS devices, Cloud Engines PogoPlug v3 based on OX820
- Broadcom – Various wireless devices: Netgear R8500 router, Tenda AC9 router, TP-LINK Archer C9 V1, Luxul XAP-1510 Access point
- STMicro – stm32f746 Cortex-M7 based microcontroller
- Texas Instruments – DRA71x automotive processors, AM571x-IDK industrial board based on TI AM5718
- Altera – Macnica Sodia development platform for Altera socfpga (Cyclone V)
- Xilinx – MicroZed board based on Xilinx Zynq FPGA platforms

That’s a long list of changes and new boards and devices… Linux 4.10 only brings few MIPS changes however:

KVM fixes: fix host kernel crashes when receiving a signal with 64-bit userspace, flush instruction cache on all vcpus after generating entry code (both for stable)
uprobes: Fix uprobes on MIPS, allow for a cache flush after ixol breakpoint creation
RTC updates: Remove obsolete code and probe the jz4740-rtc driver from devicetree for jz4740, qi_lb60
microblaze/irqchip: Moved intc driver to irqchip. The Xilinx AXI Interrupt Controller IP block is used by the MIPS based xilfpga platform and a few PowerPC based platforms.
crypto: poly1305 – Use unaligned access where required, which speeds up performance on small MIPS routers.
MIPS: Wire up new pkey_{mprotect,alloc,free} syscalls

You can also read Linux 4.10 changelog with comments only, generated using git log v4.9..v4.10 --stat, in order to get a full list of changes. Alternatively, you could also read Linux 4.9 changelog on kernelnewbies.org.

Jean-Luc Aufranc (CNXSoft)

Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.