Zephyr 4.3.0 (Working Draft)

We are pleased to announce the release of Zephyr version 4.3.0.

Major enhancements with this release include:

An overview of the changes required or recommended when migrating your application from Zephyr v4.2.0 to Zephyr v4.3.0 can be found in the separate migration guide.

The following sections provide detailed lists of changes by component.

Security Vulnerability Related

The following CVEs are addressed by this release:

More detailed information can be found in: https://docs.zephyrproject.org/latest/security/vulnerabilities.html

API Changes

Removed APIs and options

• The TinyCrypt library was removed as the upstream version is no longer maintained. PSA Crypto API is now the recommended cryptographic library for Zephyr.

• The legacy pipe object API was removed. Use the new pipe API instead.

• bt_le_set_auto_conn

• CONFIG_BT_BUF_ACL_RX_COUNT

• ok enum value has now been removed completely from base.yaml binding status property in devicetree.

Deprecated APIs and options

• maxim,ds3231 is deprecated in favor of maxim,ds3231-rtc.

• Providing a third agument to SPI_CONFIG_DT, SPI_CONFIG_DT_INST, SPI_DT_SPEC_GET, SPI_DT_SPEC_INST_GET is deprecated. Providing a second argument to SPI_CS_CONTROL_INIT is deprecated. Use new DT properties spi-cs-setup-delay-ns and spi-cs-hold-delay-ns to specify delay instead.

• bt_hci_bus was deprecated as it was not used. BT_DT_HCI_BUS_GET should be used instead.

• CONFIG_BT_AUTO_PHY_UPDATE was deprecated and has been replaced with role-specific (central vs peripheral) options that allow specifying exactly which PHY is preferred for automatic updates.

• CONFIG_POSIX_READER_WRITER_LOCKS is deprecated. Use CONFIG_POSIX_RW_LOCKS instead.

• bt_ctlr_set_public_addr() is deprecated in favor of using bt_hci_cp_vs_write_bd_addr for setting the public Bluetooth device address.

New APIs and options

• Architectures

  • CONFIG_ARCH_HAS_HW_SHADOW_STACK

  • CONFIG_SRAM_SW_ISR_TABLE

  • x86 Intel CET support

    • CONFIG_X86_CET

    • CONFIG_X86_CET_IBT

    • CONFIG_X86_CET_SHADOW_STACK_ALIGNMENT

    • CONFIG_X86_CET_SOC_PREPARE_SHADOW_STACK_SWITCH

    • CONFIG_X86_CET_VERIFY_KERNEL_SHADOW_STACK

  • ARM (Cortex-M) system state save/restore primitives

    • z_arm_save_scb_context() / z_arm_restore_scb_context()

    • z_arm_save_mpu_context() / z_arm_restore_mpu_context()

    • Existing z_arm_save_fp_context() and z_arm_save_fp_context() have also been updated

• Bluetooth

  • Audio

    • bt_audio_codec_cfg now contains a target_latency and a target_phy option

    • bt_bap_broadcast_source_foreach_stream()

    • bt_cap_initiator_broadcast_foreach_stream()

    • bt_bap_stream now contains an iso field as a reference to the ISO channel

    • bt_bap_unicast_group_get_info()

    • bt_cap_unicast_group_get_info()

  • Host

    • bt_iso_unicast_info now contains a cig_id and a cis_id field

    • bt_iso_broadcaster_info now contains a big_handle and a bis_number field

    • bt_iso_sync_receiver_info now contains a big_handle and a bis_number field

    • bt_le_ext_adv_info now contains an sid field with the Advertising Set ID.

    • CONFIG_BT_AUTO_PHY_PERIPHERAL_NONE

    • CONFIG_BT_AUTO_PHY_PERIPHERAL_1M

    • CONFIG_BT_AUTO_PHY_PERIPHERAL_2M

    • CONFIG_BT_AUTO_PHY_PERIPHERAL_CODED

    • CONFIG_BT_AUTO_PHY_CENTRAL_NONE

    • CONFIG_BT_AUTO_PHY_CENTRAL_1M

    • CONFIG_BT_AUTO_PHY_CENTRAL_2M

    • CONFIG_BT_AUTO_PHY_CENTRAL_CODED

• CPUFreq

  • Introduced experimental dynamic CPU frequency scaling subsystem

    • CONFIG_CPU_FREQ

• Display

  • PIXEL_FORMAT_AL_88

  • SDL

    • CONFIG_SDL_DISPLAY_DEFAULT_PIXEL_FORMAT_AL_88

    • CONFIG_SDL_DISPLAY_COLOR_TINT

• Kernel

  • CONFIG_HW_SHADOW_STACK

  • CONFIG_HW_SHADOW_STACK_ALLOW_REUSE

  • CONFIG_HW_SHADOW_STACK_MIN_SIZE

  • CONFIG_HW_SHADOW_STACK_PERCENTAGE_SIZE

  • K_THREAD_HW_SHADOW_STACK_SIZE

  • K_KERNEL_HW_SHADOW_STACK_DECLARE

  • K_KERNEL_HW_SHADOW_STACK_ARRAY_DECLARE

  • K_THREAD_HW_SHADOW_STACK_DEFINE

  • K_THREAD_HW_SHADOW_STACK_ARRAY_DEFINE

  • K_THREAD_HW_SHADOW_STACK_ATTACH

  • k_thread_hw_shadow_stack_attach

• LVGL (Light and Versatile Graphics Library)

  • CONFIG_LV_Z_MEMORY_POOL_ZEPHYR_REGION

  • CONFIG_LV_Z_MEMORY_POOL_ZEPHYR_REGION_NAME

  • CONFIG_LV_Z_VDB_ZEPHYR_REGION

  • CONFIG_LV_Z_VDB_ZEPHYR_REGION_NAME

• Logging:

  • CONFIG_LOG_BACKEND_SWO_SYNC_PACKETS

  • Added options to skip timestamp and level in log backends.

    • CONFIG_LOG_BACKEND_SHOW_TIMESTAMP

    • CONFIG_LOG_BACKEND_SHOW_LEVEL

  • Added rate-limited logging macros to prevent log flooding when messages are generated frequently.

    • LOG_ERR_RATELIMIT - Rate-limited error logging macro (convenience)

    • LOG_WRN_RATELIMIT - Rate-limited warning logging macro (convenience)

    • LOG_INF_RATELIMIT - Rate-limited info logging macro (convenience)

    • LOG_DBG_RATELIMIT - Rate-limited debug logging macro (convenience)

    • LOG_HEXDUMP_ERR_RATELIMIT - Rate-limited error hexdump macro (convenience)

    • LOG_HEXDUMP_WRN_RATELIMIT - Rate-limited warning hexdump macro (convenience)

    • LOG_HEXDUMP_INF_RATELIMIT - Rate-limited info hexdump macro (convenience)

    • LOG_HEXDUMP_DBG_RATELIMIT - Rate-limited debug hexdump macro (convenience)

    • LOG_ERR_RATELIMIT_RATE - Rate-limited error logging macro (explicit rate)

    • LOG_WRN_RATELIMIT_RATE - Rate-limited warning logging macro (explicit rate)

    • LOG_INF_RATELIMIT_RATE - Rate-limited info logging macro (explicit rate)

    • LOG_DBG_RATELIMIT_RATE - Rate-limited debug logging macro (explicit rate)

    • LOG_HEXDUMP_ERR_RATELIMIT_RATE - Rate-limited error hexdump macro (explicit rate)

    • LOG_HEXDUMP_WRN_RATELIMIT_RATE - Rate-limited warning hexdump macro (explicit rate)

    • LOG_HEXDUMP_INF_RATELIMIT_RATE - Rate-limited info hexdump macro (explicit rate)

    • LOG_HEXDUMP_DBG_RATELIMIT_RATE - Rate-limited debug hexdump macro (explicit rate)

• Management

  • hawkBit

    • CONFIG_HAWKBIT_REBOOT_NONE

• Modem

  • CONFIG_MODEM_DEDICATED_WORKQUEUE

• NVMEM

  • Introduced Non-Volatile Memory (NVMEM) subsystem

    • CONFIG_NVMEM

    • CONFIG_NVMEM_EEPROM

    • nvmem_cell

    • nvmem_cell_read()

    • nvmem_cell_write()

    • nvmem_cell_is_ready()

    • NVMEM_CELL_GET_BY_NAME - and variants

    • NVMEM_CELL_GET_BY_IDX - and variants

• Networking

  • CoAP

    • coap_client_response_data

    • coap_client_request.payload_cb

  • Sockets

    • zsock_listen() now implements the backlog parameter support. The TCP server socket will limit the number of pending incoming connections to that value.

• Newlib

  • CONFIG_NEWLIB_LIBC_USE_POSIX_LIMITS_H

• Opamp

  • Introduced opamp device driver APIs selected with CONFIG_OPAMP. It supports initial configuration through Devicetree and runtime configuration through vendor specific APIs.

  • Added support for NXP OPAMP nxp,opamp.

  • Added support for NXP OPAMP_FAST nxp,opamp_fast.

• Power management

  • pm_device_driver_deinit()

  • CONFIG_PM_DEVICE_RUNTIME_DEFAULT_ENABLE

  • CONFIG_PM_S2RAM has been refactored to be promptless. The application now only needs to enable any “suspend-to-ram” power state in the devicetree.

  • The PM_S2RAM_CUSTOM_MARKING has been renamed to HAS_PM_S2RAM_CUSTOM_MARKING and refactored to be promptless. This option is now selected by SoCs if they need it for their “suspend-to-ram” implementations.

• Settings

  • CONFIG_SETTINGS_TFM_ITS

• Shell

  • MQTT backend

    • CONFIG_SHELL_MQTT_TOPIC_RX_ID

    • CONFIG_SHELL_MQTT_TOPIC_TX_ID

    • CONFIG_SHELL_MQTT_CONNECT_TIMEOUT_MS

    • CONFIG_SHELL_MQTT_WORK_DELAY_MS

    • CONFIG_SHELL_MQTT_LISTEN_TIMEOUT_MS

• State Machine Framework

  • smf_get_current_leaf_state()

  • smf_get_current_executing_state()

• Storage

  • CONFIG_FILE_SYSTEM_SHELL_LS_SIZE

• Sys

  • sys_count_bits()

• Task Watchdog

  • CONFIG_TASK_WDT_DUMMY

• Toolchain

  • __deprecated_version

• Video

  • video_format.size field

  • video_estimate_fmt_size()

New Boards

New Drivers

• Input

  • chipsemi,chsc5x

• Interrupt controller

  • STM32 EXTI interrupt/event controller (st,stm32-exti) has a dedicated driver and API now, separate from STM32 GPIO Interrupt Control driver.

• MFD

  • IRQ support has been added for X-Power AXP2101 MFD device. It gets automatically enabled as soon as device-tree property int-gpios is defined on the device node.

  • Support for the power button found on the X-Power AXP2101 MFD is added and can be enabled via MFD_AXP2101_POWER_BUTTON. This feature requires interrupt support to be enabled.

• RTC

  • STM32 RTC driver has been updated to use the new STM32 EXTI interrupt controller API

• Sensors

  • we,wsen-isds-2536030320001

New Samples

• Added a new sample Operational Amplifier (OPAMP) output measure sample showing how to use the opamp device driver.

Libraries / Subsystems

• Logging:

  • Added hybrid rate-limited logging macros to prevent log flooding when messages are generated frequently. The system provides both convenience macros (using default rate from CONFIG_LOG_RATELIMIT_INTERVAL_MS) and explicit rate macros (with custom rate parameter). This follows Linux’s printk_ratelimited pattern while providing more flexibility. The rate limiting is per-macro-call-site, meaning that each unique call to a rate-limited macro has its own independent rate limit. Rate-limited logging can be globally enabled/disabled via CONFIG_LOG_RATELIMIT. When rate limiting is disabled, the behavior can be controlled via CONFIG_LOG_RATELIMIT_FALLBACK to either log all messages or drop them completely. For more details, see Rate-limited logging.

• Secure storage

  • The experimental status has been removed. (GitHub #96483)

Other notable changes

• Nordic Semiconductor nRF54L09 PDK (nrf54l09pdk), which only targeted an emulator, has been removed from the tree. It will be replaced with a proper board definition as soon as it’s available.

• Removed support for Nordic Semiconductor nRF54L20 PDK (nrf54l20pdk) since it is replaced with nRF54LM20 DK (nrf54lm20dk).