Release-2022.07

RIOT-2022.07 - Release Notes

RIOT is a multi-threading operating system which enables soft real-time
capabilities and comes with support for a range of devices that are typically
found in the Internet of Things: 8-bit and 16-bit microcontrollers as well as
light-weight 32-bit processors.

RIOT is based on the following design principles: energy-efficiency, soft
real-time capabilities, small memory footprint, modularity, and uniform API
access, independent of the underlying hardware (with partial POSIX compliance).

RIOT is developed by an international open-source community which is
independent of specific vendors (e.g. similarly to the Linux community) and is
licensed with a non-viral copyleft license (LGPLv2.1), which allows indirect
business models around the free open-source software platform provided by RIOT.

About this release

The 2022.07 release includes many changes, some highlights of which are:

GPIO Low-level drivers

A new API, gpio_ll, has been introduced for highly efficient access to GPIO
pins grouped in ports.

The API is limited to internal use for the time being, but still paves the way
towards using port multipliers like local GPIO pins, and for improved
bit-banging implementations (e.g. around WS281x-style LEDs).

Improved serial port selection

When using multiple boards simultaneously, a new serial port selection
algorithm can be activated by setting MOST_RECENT_PORT=1. Of all serial ports
whose metadata matches the board's known properties, it selects the most
recently connected one.

ESP support

The ESP IDF (IoT Development Framework; the vendor's provided tools) has been
upgraded to version 4.4, and many peripheral drivers are now implemented using those.

343 pull requests, composed of 767 commits, have been merged since the
last release, and 5 issues have been solved. 38 people contributed with
code in 107 days. 1684 files have been touched with 43451 (+) insertions and
82174 deletions (-).

Notations used below

+ means new feature/item
* means modified feature/item
- means removed feature/item

New features and changes

Core

• provide dummy implementation of thread and mutex for riotboot (#17959)
• kernel_defines: drop CONST definition (#18212)

System Libraries

• sys/event: Add documentation and enforce waiter on wait (#17952)
  sha256sum shell commands (#18040)
• sys/shell: new module shell_lock (#13082)

• Fido2: Enhance flash persistence (#17096)
• pkg/fatfs, shell: enable RTC support if rtt_rtc is used (#17912)
• pm: don't (un)block IDLE mode (#17974)
• sys/posix/include/arpa: use __restrict instead of restrict (#18034)
• sys/quad_math: remove unused module for quad arithmetic (#18032)
• sys/shell: drop _builtin_cmds define (#18075)
• sys/shell_commands: convert to SHELL_COMMAND() (#18152)
• sys/ztimer: no log for stdio_rtt/semihosting (#18176)

SUIT

• suit/transport/vfs: add VFS as source for firmware updates (#18045)
• sys/sc_suit: add seq_no command (#17941)

• examples/suit_update/test: use 'suit seq_no' to get version (#17973)
• sys/suit/storage/vfs: initial import (#17943)
• sys/suit/storage: change log to LOG_DEBUG (#18020)
• sys/suit: avoid installing payload twice (#17984)
• sys/suit: save seq_number when parsing manifest (#17939)

VFS

• sys/shell/vfs: add umount, rmount and mkdir commands (#18112)
• sys/vfs: add vfs_unmount_by_path() (#18109)
• sys/vfs_util: add VFS helper functions (#18038)
• sys/vfs_util: add vfs_file_() functions and md5sum, sha1sum and

Rust

• Add some Rust library building infrastructure (#16833)

• makefiles/rust: Err early on setup issues, provide suggestions (#18220)
• rust: Build from git branches (#18151)
• rust: Explicitly select nightly (#18243)
• rust: Update versions (#18181)

Networking

• congure_reno: initial import of TCP Reno congestion control (#15953)
• drivers/sx1280: add driver for SX1280 transceiver v2 (#18033)
• gnrc/ipv6_auto_subnets: init RPL root when adding a prefix (#17350)
• ieee802154: add default max frame retransmissions config (#18264)
• pkg/lwip: Add basic version of netif_get/set_opt (#18069)
• pkg/lwip: Add netif_t struct, register all netifs (#16974)
• pkg/nimble/autoadv: add support for ext_adv (#17774)
• sys/iolist: add helper functions (#18044)
• sys/net/gnrc: add gnrc_tx_sync for gnrc_sixlowpan_frag_sfr (#16090)
• sys/net/gnrc_pktbuf_static: add use-after-free detection (#18227)
• sys/net/netif: add convenience functions for getting/printing IPv6
  addresses (#18161)

• gnrc/ipv6_auto_subnets: allow to join multiple subnets (#17547)
• gnrc_ipv6_nib: fix inconsistent ABR valid lifetime representation (#18126)
• gnrc_netif: make auto-config of compression context optional (#17678)
• gnrc_netif: use event loops by default to process ISR (#16748)
• gnrc_sock: implicitly set netif if there is only a single one (#18065)
• gnrc_sock: warn about non-zero receive timeouts with sock_async (#17691)
• net/ble/skald: make advertising interval configurable per context (#17834)
• net/gnrc: Fixing whitespace in the documentation (#18036)
• net/sock/udp: designated initializer, C++ compatibility (#18035)
• sock_dns: implement DNS cache (#17680)
• sock_dns_cache: move to dns_cache (#18318)
• sock_dns_cache: move to dns_cache [backport 2022.07] (#18327)
• sys/include/net/af: fix doc comment (#17946)
• sys/net/gnrc_pktbuf_static: fix documentation of use-after-free
  detection (#18244)
• tests: rework ieee802154 drivers (#17838)

GCoAP

• Add file server (#17956)
• add helper function to get request header from a request memo (#18095)
• add nanocoap_cache support for clients (#17888)
• DNS: initial import of a DNS over CoAP (DoC) client (#16705)
• Forward prxy: provide cache validation mechanism (#17801)

• ensure response address is the same as request address (#18026)
• small dependencies fixes (#17944)

Nanocoap

• add coap_get_token() (#17976)
• Add handler for resource-based subtrees (#13698)
• cache for CoAP responses (#13889)
• add nanocoap_sock_block_request() (#17958)
• add nanocoap_sock_url_connect() (#17960)
• add nanocoap_vfs_get() (#17937)
• add nanocoap_vfs_put() (#17962)

• follow-up fixes (uncontroversial parts) (#17977)
• clean up state management (#18047)
• deprecate coap_pkt token ptr (#18013)
• refactor to remove work-buffer requirement (#17509)

Packages

• drivers/atwinc15x0: add timeout to init (#18214)
• pkg/libcose: add RIOT as crypto backend (#17701)
• pkg/pkg: add GIT_QUIET (#17987)
• tests/pkg_cmsis-dsp: add kconfig configuration + cleanup package
  modules (#18001)

• makesystem: speedup pkg cloning if no git-cache is available (#16316)
• pkg/littlefs2: bump version to 2.5.0 (#18049)
• pkg/lv_drivers: cleanup Makefile (#18302)
• pkg/lvgl: bump to v8.3.0 (#18301)
• pkg/minmea: bump version (#18166)
• pkg/nanopb: bump version to 0.4.6 (#18149)
• pkg/pkg.mk: silence info if QUIETER (#18031)
• pkg/uwb-core: adjust holdoff time when rxdiag_enabled (#17999)
• pkg/uwb-core: reduce default stacksize (#18022)
• pkg/uwb-core: remove uwbcfg (#17998)
• pkg/uwb-dw1000: fix default group delay, use OTP values when possible (#18000)
• pkg/wamr: update to tagged release WAMR-05-18-2022 (#18119)

Boards

• boards/nucleo-f401re: add riotboot (#17948)
• boards/stm32f7508-dk: add support (#17954)
• cpu/samd5x: add SD Host Controller implementation (#17863)

• boards/adafruit-pybadge: enable ST7735 display (#17903)
• boards/common/arduino-atmega: fix issue with wrong port for LED0 (#18245)
• boards/esp32: cleanup board_init_common (#18238)
• boards/esp32: cleanup CI compilation for esp_wifi_enterprise (#18218)
• boards/nucleo-X: enable cpy2remed programmer (#18057)
• boards/stm32f469i-disco: enable cpy2remed programmer (#18039)
• boards/{thingy52,ruuvitag}: allow OpenOCD as programmer (#18237)
• build system: improve serial port selection (#18167)
• cpu/esp32: Upgrade to ESP-IDF v4.4 (#17601)
• cpu/esp32: use ESP-IDF i2c HAL for ESP32 periph/i2c (#18279)
• cpu/esp32: use ESP-IDF ledc HAL for periph/pwm (#18276)
• drivers/lcd: rework rotation management and enable it for st7735 (#17930)
• drivers/lcd: slightly rework params to expose offset values to
  ili9341 driver (#17925)
• periph_can,candev: socketcan pkg for native, candev test cleanup (#17533)
• pkg/cryptoauthlib: Update package to latest version (#18137)
• unittests: enable ASAN on native (#18099)

CPU

• netdev_tap: make 'wired' property configurable (#17709)
• pkg/nimble: version bump to NimBLE 1.5.0 RC1 (#18029)

AVR

• atmega_common: implement periph/gpio_ll{,_irq} (#17982)

Cortex-M

• cortexm_common: allow to overwrite nmi_handler (#18232)
• cortexm_common: enable FPU on cortexm33 (#18064)
• cortexm_common: remove breakpoint from hard_fault_handler (#17781)

• efm32: Minimal support for gpio_ll (#18023)
• nrf5x_common: implement periph/gpio_ll{,_irq} (#17980)
• stm32: Implement periph/gpio_ll{,_irq} except for STM32F1 (#17981)

• sam0_common: adc: Automatically configure external reference pin (#18042)
• stm32: support for B subfamily of g0 to determine the ram length (#18296)

ESP32

• add ESP-IDF API (#18253)

• use ESP-IDF ...
  • adc/dac HAL for periph/adc and periph/dac (#18271)
  • function esp_efuse_mac for CPU ID (#18273)
  • gpio HAL for periph/gpio (#18270)
  • interrupt HAL for periph/uart (#18274)
  • interrupt handling API (#18261)
  • random API for ESP32 (#18277)
  • sleep API for periph/pm (#18280)
  • spi HAL for periph/spi (#18281)
  • spli_flash_* funcs in periph/flash (#18250)
  • startup function (#18268)
  • timer HAL for system timer and watchdog (#18267)
  • timer/interrupt HAL for periph/timer (#18282)
  • twai HAL for periph/can (#18278)
• ESP32x SoC variant independent syscalls (#18266)
• always include libc_gettimeofday (#18027)
• ESP32 SoCx variant independent bootloader makefile (#18246)
• ESP32x SoC variant independent makefiles (#18249)
• invert MCU_* and CPU* conditionals (#18248)
• move platform code for Xtensa-based ESP32x SoCs to module esp_xtensa (#18259)
• Remove dependency on module libc_gettimeofday (#18202)
• split module esp_wpa supplicant into several modules (#18239)
• FreeRTOS adaptation layer changes/extension required for ESP-IDF HAL/LL
  (#18224)
• use LittleFS2 as default FS (#18159)
• pkg/esp32_sdk: Update version to 4.4.1 (#18165)

Device Drivers

• periph/gpio_ll: New Peripheral GPIO API (#16787)
• driver/lcd: add common lcd base driver (#16176)
• sys/mtd: Introduce write granularity (#17683)

• drivers/mtd_mapper: inherit physical properties (#18113)

• drivers/netdev_ieee802154: drop duplicate struct member (#17979)

• drivers/periph_common/cpuid: disable false positive warnings (#17909)

• drivers/hd44780: PCF857x I2C interface added (#12665)

• drivers/ir_nec: NEC remote receiver implementation (#17935)

• drivers/mcp2515: enable filtering (#18062)

• drivers/mcp2515: apply filters to target mailbox (#18131)

• drivers/mcp2515: fixes and cleanups (#17945)

• drivers/scard_spi: _dyn_spi_rxtx_byte return void (#17968)

• drivers/ws281x: update ESP32 driver to use ESP-IDF CPU HAL (#18252)

• pkg/driver_atwinc15x0: bump version to 1.6.1 (#18215)

Documentation

• boards/nucleo144: doc update - usage of cpy2remed programmer and
  short overview of board (#18291)
• boards/nucleo32: doc update - usage of cpy2remed programmer and short
  overview of board (#18225)
• cpu/esp32: small doc fixes (#18240)
• doc/rust: Update texts (#18208)
• doc: fix broken link/footnote in using-rust.md/maintenance (#17961)
• Documentation: Renaming OS X to macOS (#18256)
• native/periph_can: usability improvements and documentation updates (#17949)
• pkg/hacl: documentation link update (#18002)

Build System / Tooling

• dist/tools/suit: add support for password protected private keys (#18130)
• examples/gnrc_border_router: allow to use gnrc_ipv6_auto_subnets for
  prefix configuration (#16993)

• .murdock: print hash input when hashes mismatch (#18236)
• buildsystem: Improve RISC-V compilation handling with newer toolchain (#18098)
• buildsystem: split default modules include early and late (#17662)
• dist/tools/compile_and_test_for_board: fix lint (#18160)
• dist/tools/cosy: allow to specify port (#18194)
• make: create cargo folders for Docker images (#18086)
• makefiles/tools/uf2conv.inc.mk: partial riotboot support (#16323)
• makefiles: allow to override suit manifest payloads (#16771)
• makefiles: Reject 2>&1 >/dev/null, and weed out remaining offenders (#16806)
• tools/edbg: bump version (#18076)
• tools/zep_dispatch: allow to pin nodes to MAC address (#17338)
• tools/zep_dispatch: run dispatch with custom topology (#18170)

Kconfig

• drivers/cst816s: add touch_dev interface + add Kconfig + migrate to
  ztimer (#17459)
• pkg/tflite-micro: add kconfig support (#17985)
• sys/cpp11-compat: add kconfig support and add Kconfig for cpp11 test
  applications (#17992)

• pkg/cmsis-nn: model in Kconfig (#17997)
• pkg/corejson: fix missing kconfig import + model test application
  configuration (#18008)
• pkg/cryptoauthlib: model in kconfig (#18011)
• pkg/jerryscript: model in Kconfig (#18012)
• pkg/lua: model in kconfig (#18017)
• pkg/nanors: model in kconfig (#18024)
• sys/random/kconfig: remove HWRNG default in backend choice (#18025)
• tests/pkg_utensor: model in Kconfig + fix utensor package
  dependencies (#17995)
• tests/{cpp_ext, cpp_exclude}: model in kconfig (#17994)

Examples

• examples/telnet_server: add support for LWIP (#17899)

• example/twr_aloha: fixes (#17988)
• examples/lorawan/main: use auto_init_loramac (#17695)
• examples/suit_udpate: update check suit command (#17963)

Testing

• cpu/esp: add compilation tests for optional ESP modules (#18158)
• unittest/sock_util: add test for missing addr variants (#18061)

• CI: disable microbit testing (#17933)
• gh_action/test-on-iotlab: update available boards (#18303)
• murdock: don't do both "clean" and "test-input-hash" targets (#18254)
• test/pbkdf2: enlarge stdio rx buffer (#17928)
• tests/pkg_tflite-micro: update list of low memory boards (#18101)
• tests/{cpp_ext, cpp_exclude}: cleanup HAS_* (#18082)
• tests: move riot_logo.h to tests base directory (#17917)
• unittest/sock_util: move test_strings to their tests (#18067)

API Changes

• drivers/disp_dev: use struct to store display area coordinates (#17921)
• makefiles/suit: place keys in $XDG_DATA_HOME (#18157)
• nanocoap: define and use coap_request_ctx_t for request handlers (#17957)
• sys/shell/gnrc_netif: List netifs in registration order (#17078)

And countless minor changes.

Deprecations

Deprecations (1)

• ztimer: deprecate ztimer_now64 and ztimer_now_t (#18054, #18105)

Removals (2)

• net/netopt: drop NETOPT_RX_END_IRQ (#18089)
• pkg/lvgl7: remove deprecated package (#18304)

Bug fixes (64)

• cpu/stm32/include/periph/f7: add missing ADC_DEVS (#17923)
• dist/tools/kconfiglib: add configuration evaluation function (#18192)
• drivers/periph/timer: add TIM_FLAG_SET_STOPPED flag (#17723)
• drivers/st7735/kconfig: add hardware feature symbol (#18135)
• gnrc/nib: don't add routers from WPAN as default router on the 6LBR (#18127)
• [Backport] asymcute: Compare request message type when matching
  acknowledgement (#18446)
• [Backport] asymcute: fix one byte out-of-bounds access in _len_get (#18453)
• asymcute: Fix deadlocks in REGACK, SUBACK and UNSUBACK handler (#18289)
• bitarithm: Move extern const out of static inline functions (#18140)
• boards/common/nrf52: fix compilation of thingy52 and ruuvitag (#18180)
• boards/im880b: im880b board clock definition (#18295)
• boards/stm32f469i-disco: LEDX_ON LEDX_OFF mismatch (#18041)
• build system: Fix compilation for RISC-V with newer GCC (#17951)
• core/assert: print last instruction in assert() (#18195)
• core/msg: yield after thread_flags_wake() in queue_msg() (#16899)
• cpu/atmega_common: Fix atmega_port_addr() (#18265)
• cpu/esp32: fix malloc thread safety (#18209)
• cpu/esp32: fix pm_reboot function (#18207)
• cpu/esp32: fixes for gcc 8.4.0 (#18104)
• cpu/sam0_common: mtd_sdhc: ensure source address alignment (#18222)
• cpu/samd21: handle NVM block errata (#18188)
• cpu/stm32/periph_eth: fix typo in initialization code [backport
  2022.07] (#18420)
• cpu/{atmega_common,atxmega}: increase idle thread stack size (#18263)
• dirvers/mtd: fix documentation of mtd_write_page_raw() and
  mtd_read_page() (#18231)
• dist/tools/compile_commands: don't adds -nostdinc (#18080)
• dist/tools/compile_commands: fix clangd linting (#18063)
• dns_cache: synchronize access with mutex [backport 2022.07] (#18342)
• docker: don't export KCONFIG_ADD_CONFIG variable (#17993)
• drivers/at86rf2xx: fix NETOPT_RANDOM (#18305)
• drivers/at86rf2xx: Switch SRT mode to get random values. (#18290)
• drivers/atwinc15x0: disconnect when sleeping (#17889)
• drivers/mcp2515: fix set bittiming (#18019)
• drivers/rtt_rtc: normalize tm struct in rtc_set_alarm (#18197)
• examples/dtls-echo: set address family for sessions [backport
  2022.07] (#18371)
• examples/lorawan: disable loramac state persistence on EEPROM (#17969)
• gcoap: fixes around empty ACKs [backport 2022.07] (#18436)
• gcoap_dns: various fixes [backport 2022.07] (#18373)
• gnrc/ipv6_auto_subnets: always send RIO to upstream network (#18187)
• gnrc/nib: only enable RTR_ADV on RA if MULTIHOP_P6C is enabled (#17600)
• gnrc_dhcpv6_client: Fix out-of-bounds access during option parsing (#18307)
• gnrc_ipv6_nib: make configurable via Kconfig again [backport 2022.07] (#18362)
• gnrc_netif_conf: fix auto-6ctx switch [backport 2022.07] (#18375)
• gnrc_netif_pktq: protect against concurrent access (#18153)
• gnrc_netreg: drain mbox on unregister (#18143)
• ipv6/nib: bugfix handle SLLAO on 6LR if ARO is not present (#17814)
• makefiles/boot/riotboot: set DEBUG_ELFFILE to slot0.elf (#18138)
• nanocoap: follow-up fixes (#17950)
• nanocoap_sock: fix wrong assertion (#18221)
• net/eui_provider: provide netif index to EUI provider function (#18251)
• pkg/ccn-lite: patch to fix use-after-free [backport 2022.07] (#18488)
• pkg/emlearn: fix kconfig model (#18306)
• pkg/emlearn: Remove unused emlearn module (#18287)
• pkg/mynewt-core: fix timer configuration for nrf51 (#18136)
• release-tests: install libasan as native dependency (#18124)
• sys/fmt: disarm footgun (#18162)
• sys/fmt: fix output on native (#18186)
• sys/net/gnrc/rpl: sync access to netstats (#18275)
• sys/net/netopt: change NETOPT_STATS semantics (#18269)
• sys/rtc_utils: small doc fix of rtc_mktime (#18196)
• sys/uri_parser: check port length (#18092)
• tests/thread_float: fix test script (#18255)
• unittest: fix ztimer(64)_initilization #18352 #18365 [backport
  2022.07] (#18377)
• unittests: fix assertion for nanocoap_cache_key_compare() (#18125)
• vfs: fix dir detection in vfs_sysop_stat_from_fstat() (#18050)

Known issues

Network related issues (58)

• 6lo gnrc fragmentation expects driver to block on TX (#7474)
• 6lo: RIOT does not receive packets from Linux when short_addr is set (#11033)
• [gcoap-dtls] Posting a message yields a stack overflow on the
  samr21-xpro with ECC (#18292)
• Address registration handling inappropriate (#15867)
• app/netdev: application stops working after receiving frames with
  assertion or completely without error (#8271)
• at86rf2xx: Dead lock when sending while receiving (#8242)
• at86rf2xx: lost interrupts (#5486)
• CC2538 RF overlapping PIN usage (#8779)
• cpu/esp8266: Tracking open problems of esp_wifi netdev driver (#10861)
• dist/tools/sliptty/start_network.sh: IPv6 connectivity is broken on
  PC (#14689)
• driver/mrf24j40: blocks shell input with auto_init_gnrc_netif (#12943)
• drivers/at86rf215: Incorrect channel number set for subGHz (#15906)
• DTLS examples cannot send message to localhost (#14315)
• Emcute cannot create a double-byte name (#12642)
• ethernet: Missing multicast addr assignment (#13493)
• ethos: fails to respond to first message. (#11988)
• ethos: Unable to choose global source address. (#13745)
• ethos: Unable to handle fragmented IPv6 packets from Linux kernel (#12264)
• examples/cord_ep: Dead lock when (re-)registering in callback
  function (#12884)
• examples/gnrc_border_router: esp_wifi crashes on disconnect (#14679)
• Forwarding a packet back to its link layer source should not be
  allowed (#5051)
• gcoap example request on tap I/F fails with NIB issue (#8199)
• gcoap: Suspected crosstalk between requests (possible NULL call) (#14390)
• General 802.15.4/CC2538 RF driver dislikes fast ACKs (#7304)
• gnrc ipv6: multicast packets are not dispatched to the upper layers (#5230)
• gnrc_border_router stops routing after a while (#16398)
• gnrc_icmpv6_echo: flood-pinging another node leads to leaks in own
  packet buffer (#12565)
• gnrc_ipv6: Multicast is not forwarded if routing node listens to the
  address (#4527)
• gnrc_netif_pktq leaks memory (#17924)
• gnrc_rpl: missing bounds checks in _parse_options (#16085)
• gnrc_rpl: nib route not updated when topology / DODAG changes (#17327)
• gnrc_sock_udp: Possible Race condition on copy in application buffer (#10389)
• gnrc_tcp: gnrc_tcp_recv() never generates -ECONNABORTED (#17896)
• gomach: Resetting netif with cli doesn't return (#10370)
• ieee802154_submac: IPv6 fragmentation broken (#16998)
• LoRaWan node ISR stack overflowed (#14962)
• lwip_sock_tcp / sock_async: received events before calling
  sock_accept() are lost due to race condition. (#16303)
• Missing drop implementations in netdev_driver_t::recv (#10410)
• nanocoap: problem with [re]transmission behaviour: (some blocks are
  sent twice immediately) (#18217)
• Neighbor Discovery not working after router reboot when using SLAAC (#11038)
• net: netdev_driver_t::send() doc unclear (#10969)
• netdev_ieee802154: Mismatch between radio ll address and in memory
  address (#10380)
• nrf52: Not able to add global or ULA address to interface (#13280)
• nrfmin: communication not possible after multicast ping with no
  interval (#11405)
• openthread: does not build on current Arch (#10809)
• ping6 is failing when testing with cc2538dk (#13997)
• pkg/tinydtls: auxiliary data API does not work for async sockets (#16054)
• Possible memory leak in RIOT/build/pkg/ndn-riot/app.c (#15638)
• Riot-os freezes with lwip + enc28j60 + stm32L4 (#13088)
• samr30 xpro doesn't seem to use its radio ok (#12761)
• scan-build errors found during 2019.07 testing (#11852)
• send data with UDP at 10HZ, the program die (#11860)
• stale border router does not get replaced (#12210)
• test/lwip: enabling both, IPv4 and IPv6, results in unexpected
  behavior (#18097)
• tests/lwip: does not compile for IPv4 on 6LoWPAN-based boards. (#17162)
• two nodes livelock sending neighbor solicitations back and forth
  between each other (#16670)
• Unclear how Router Solicitations are (or should be) handled (#15926)
• xbee: setting PAN ID sometimes fails (#10338)

Timer related issues (16)

• cpu/native: timer interrupt issue (#6442)
• misc issues with tests/trickle (#9052)
• MSP430: periph_timer clock config wrong (#8251)
• periph/timer: timer_set() underflow safety check (tracking issue) (#13072)
• periph_timer: systematic proportional error in timer_set (#10545)
• saml21 system time vs rtc (#10523)
• Sleep mode for Arduino (#13321)
• stm32_common/periph/rtc: current implementation broken/poor accuracy (#8746)
• sys/newlib: gettimeofday() returns time since boot, not current wall
  time. (#9187)
• tests/periph_timer_short_relative_set results are misleading (#18511)
• tests: xtimer_drift gets stuck on native (#6052)
• xtimer mis-scaling with long sleep times (#9049)
• xtimer: add's items to the wrong list if the timer overflows between
  _xtimer_now() and irq_disable() (#7114)
• xtimer_set_msg: crash when using same message for 2 timers (#10510)
• xtimer_usleep stuck for small values (#7347)
• xtimer_usleep wrong delay time (#10073)

Drivers related issues (18)

• (almost solved) SPI SD-Card driver: SPI initialisation freeze until
  timeout (#14439)
• adc is not a ADC-Driver but a analog pin abstraction (#14424)
• at86rf2xx: Simultaneous use of different transceiver types is not
  supported (#4876)
• cpu/msp430: GPIO driver doesn't work properly (#9419)
• driver/hts221: Temperature and Humidity readings incorrect (#12445)
• ESP32 + DHT + SAUL reading two endpoints causes freeze. (#12057)
• examples/dtls-wolfssl not working on pba-d-01-kw2x (#13527)
• fail to send data to can bus (#12371)
• floats and doubles being used all over the place. (#12045)
• mdt_erase success, but vfs_format resets board (esp32-heltec-
  lora32-v2) (#14506)
• periph/spi: Switching between CPOL=0,1 problems on Kinetis with
  software CS (#6567)
• periph: GPIO drivers are not thread safe (#4866)
• Potential security and safety race conditions on attached devices (#13444)
• PWM: Single-phase initialization creates flicker (#15121)
• STM32: SPI clock not returning to idle state and generating
  additional clock cycles (#11104)
• TCP client cannot send read only data (#16541)
• tests/periph_flashpage: unexpected behavior on nucleo-l4r5zi (#17599)
• Two bugs may lead to NULL dereference. (#15006)

Native related issues (6)

• examples/ccn-lite: floating point exception while testing on native (#15878)
• examples/micropython: floating point exception while testing on
  native (#15870)
• native getchar is blocking RIOT (#16834)
• native not float safe (#495)
• native: tlsf: early malloc will lead to a crash (#5796)
• SIGFPE on native architecture when printing double floats on Ubuntu
  21.04 (#16282)

Other platforms related issues (21)

• Failing tests on FE310 (Hifive1b) (#13086)
• [TRACKING] Fixes for automatic tests of ESP32 boards. (#12763)
• arm7: printf() with float/double not working (#11885)
• boards/hifive1: flashing issue (#13104)
• Cannot use LLVM with Cortex-M boards (#13390)
• cpu/cortexm_common: irq_enable returns the current state of
  interrupts (not previous) (#10076)
• cpu/sam0: flashpage write / read cycle produces different results
  depending on code layout in flash (#14929)
• cpu/stm32f1: CPU hangs after wake-up from STOP power mode (#13918)
• esp32-wroom-32: tests/netstats_l2 failing sometimes (#14237)
• esp8266 precompiled bootloaders don't support partitions past 1MB (#16402)
• gcoap/esp8266: Stack overflow with gcoap example (#13606)
• I found stm32 DMA periph driver bugs! when I tested stm32l431rc
  board. (#16242)
• Incorrect default $PORT building for esp32-wroom-32 on macOS (#10258)
• MIPS: toolchain objcopy doesn't work and no .bin can be generated (#14410)
• MPU doesn't work on cortex-m0+ (#14822)
• newlib-nano: Printf formatting does not work properly for some
  numeric types (#1891)
• periph_timer: Test coverage & broken on STM32F767ZI (#15072)
• riscv: ISR stack is too small for ENABLE_DEBUG in core files (#16395)
• stm32152re: hardfault when DBGMCU_CR_DBG* bits are set and branch
  after __WFI() (#14015)
• stm32f7: Large performance difference between stm32f746 and stm32f767 (#14728)
• sys/riotboot/flashwrite: unaligned write when skipping
  RIOTBOOT_MAGIC on stm32wb (#15917)

Build system related issues (13)

• buildtest uses wrong build directory (#9742)
• make -j flash fails due to missing make dependencies or make flash-only rebuilds the .elf (#16385)
• Build dependencies - processing order issues (#9913)
• build: info-build doesn't work with boards without port set (#15185)
• BUILD_IN_DOCKER ignores USEMODULE (#14504)
• dist/tools/cppcheck/cppchck.sh: errors when running with Cppcheck
  1.89 (#12771)
• doxygen: riot.css modified by 'make doc' (#8122)
• macros: RIOT_FILE_RELATIVE printing wrong file name for headers (#4053)
• make: ccache leads to differing binaries (#14264)
• make: Setting constants on compile time doesn't really set them
  everywhere (#3256)
• make: use of immediate value of variables before they have their
  final value (#8913)
• Tracking: remove harmful use of export in make and immediate
  evaluation (#10850)
• Windows AVR Mega development makefile Error (#6120)

Other issues (57)

• semtech_loramac_init blocking (#17907)
• [TRACKING] sys/shell refactoring. (#12105)
• _NVIC_SystemReset stuck in infinite loop when calling pm_reboot
  through shell after flashing with J-Link (#13044)
• make term no longer works with JLinkExe v6.94 (#16022)
• make term output is inconsistent between boards, ethos and
  native (#12108)
• assert: c99 static_assert macro doesn't function for multiple
  static_asserts in the same scope (#9371)
• Basic test for periph/rtt introduced in #15431 is incorrect (#15940)
• boards/esp32-wroom-32: tests/mtd_raw flakey (#16130)
• Bug: openocd 0.10.0-6 Ubuntu dies while debugging with -rtos auto (#13285)
• C++11 extensions in header files (#5561)
• Can't build relic with benchmarks or tests (#12897)
• CC2538DK board docs: broken links (#12889)
• cpu/stm32/periph/rtc overflow error (#16574)
• cpu/stm32: some tests are failing on CM33 (l5, u5) (#17439)
• doc/LOSTANDFOUND: not rendered as expected (#17063)
• edbg: long lines flooded over serial become garbled (#14548)
• examples / tests: LoRa tests fail on platforms that don't support
  LoRa (#14520)
• feather-m0: make flash reports "device unsupported" (#17722)
• flashing issue on frdm-k64f (#15903)
• frdm-k22f failing tests/periph_flashpage (#17057)
• I2C not working under RIOT with U8G2 pkg (#16381)
• ieee802154_security: Nonce is reused after reboot (#16844)
• lwip: drivers/at86rf2xx/at86rf2xx_netdev.c invalid state during TCP
  disconnect (#17209)
• lwip: invalid state transition on ieee802154_submac users (#17208)
• Making the newlib thread-safe (#4488)
• mcuboot: flashes but no output (#17524)
• nanocoap: incomplete response to /.well-known/core request (#10731)
• newlib-nano: Printf formatting does not work properly with "PRIu8" (#17083)
• Order of auto_init functions (#13541)
• pkg/tinydtls: Multiple issues (#16108)
• pkg_libhydrogen tests fail / update libhydrogen (#18508)
• Possible memset optimized out in crypto code (#10751)
• Potential race condition in compile_and_test_for_board.py (#12621)
• pyterm on stdio_cdc_acm stops working after a few seconds (#16077)
• RIOT cannot compile with the latest version of macOS (10.14) and
  Xcode 10 (#10121)
• RIOT is saw-toothing in energy consumption (even when idling) (#5009)
• riotboot/nrf52840dk: flashing slot1 with JLINK fails (#14576)
• riotboot: ECC faults (eg. in STM32L5 or STM32WB) not handled
  gracefully (#17874)
• rust-gcoap example is incompatible with littlefs2 (#17817)
• sam0_sdhc: SDXC cards are not detected / handled properly (#18458)
• scheduler: priority inversion problem (#7365)
• stdio_ethos: infinite shell loop (#17972)
• sys/fmt: Missing tests for fmt_float, fmt_lpad (#7220)
• sys/riotboot: documentation issues (#11243)
• sys/stdio_uart: dropped data when received at once (#10639)
• tests/cpp11_*: failing on i-nucleo-lrwan1 (#14578)
• tests/lwip target board for python test is hardcoded to native (#6533)
• tests/periph_flashpage: failing on stm32l475ve (#17280)
• tests/pkg_libhydrogen: test fails on master for the samr21-xpro with
  LLVM (#15066)
• tests/pkg_tensorflow-lite: tests randomly failing on nrf52dk and
  esp32-wroom-32 (#13133)
• tests/test_tools: test fails while testing on samr21-xpro/iotlab-m3 (#15888)
• tests/thread_float: crashes on avr-rss2 (#16908)
• tests: broken with stdio_rtt if auto_init is disabled (#13120)
• tests: some tests don't work with newlib lock functions. (#12732)
• Tracker: Reduce scope on unintended COMMON variables (#2346)
• usb-serial/list-ttys.sh: Broken when a debugger offers multiple
  serial ports (#15814)
• Use of multiple CAN bus on compatible boards (#14801)

There are 188 known issues in this release

Fixed Issues since the last release (2022.04)

• core: "Invalid read of size 4" (#7199)
• Use-after-free in ccnl-core (#18480)
• [puf_sram] Hardfault (#18468)
• esp32: gnrc_networking crashing (#18083)
• boards/saml11-xpro: second UART is broken (#17206)

5 fixed issues since last release (2022.04)

Acknowledgements

We would like to thank all companies that provided us with hardware for porting
and testing RIOT-OS. Further thanks go to companies and institutions that
directly sponsored development time. And finally, big thanks to all of you
contributing in so many different ways to make RIOT worthwhile!

More information

http://www.riot-os.org

Matrix and Forum

• Join the RIOT Matrix room at: #riot-os:matrix.org
• Join the RIOT Forum at: forum.riot-os.org

License

• The code developed by the RIOT community is licensed under the GNU Lesser
  General Public License (LGPL) version 2.1 as published by the Free Software
  Foundation.
• Some external sources and packages are published under a separate license.

All code files contain licensing information.