Apache NuttX is a mature, real-time embedded operating system (RTOS) https://nuttx.apache.org/
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liang.huang 32cf92db24 arch/risc-v: qemu: don't rewind interrupt stack sp on nested trap
qemu-rv's S-mode/non-SMP setintstack unconditionally reloaded sp to
the top of the per-cpu interrupt stack.  A trap taken while already
running on that stack rewound sp back to the same address, so the
nested trap's frame overwrote the still-live outer trap's frame.

Port the bounds check already used by the canonical setintstack in
riscv_macros.S: only move sp when it is outside the interrupt stack
range.

Other vendor chip.h files have the same unconditional-reload pattern
and are left for a follow-up.

Signed-off-by: liang.huang <liang.huang@houmo.ai>
2026-07-18 20:04:01 +08:00
.github ci/testing: MemBrowse Doc only change detection fix 2026-07-14 11:03:49 -03:00
arch arch/risc-v: qemu: don't rewind interrupt stack sp on nested trap 2026-07-18 20:04:01 +08:00
audio drivers/efuse/efuse: Drivers Registered With World Write Permissions(Part 1) 2026-07-13 12:08:01 +02:00
binfmt elf:use elf symbol to parse attribute 2026-07-15 12:24:44 -03:00
boards boards/mips: Add networking support to CI20 board 2026-07-17 16:14:14 -03:00
cmake cmake: Sanitize NAME for _main symbol generation 2026-07-17 13:04:26 -03:00
crypto crypto: add CRYPTO_AES_CTR_SSH variant (128-bit big-endian counter) 2026-07-16 15:42:10 +08:00
Documentation boards/mips: Add networking support to CI20 board 2026-07-17 16:14:14 -03:00
drivers drivers/watchdog: fix capture automonitor notifier context 2026-07-17 14:59:47 +08:00
dummy build: add initial cmake build system 2023-07-08 13:50:48 +08:00
fs libs/libc: Fix divide-by-zero in stat() with large filesystem block sizes 2026-07-16 23:37:22 +08:00
graphics drivers/: Multiple Drivers Are Registered With World Writable - Part 2 2026-07-15 15:27:28 +08:00
include boards/mips: Add networking support to CI20 board 2026-07-17 16:14:14 -03:00
libs spawn: allow zero stacksize/priority to use binary loader defaults 2026-07-15 12:24:44 -03:00
mm arch/mips: Add basic support for MIPS Creator CI20 board 2026-07-15 08:02:55 -03:00
net fix(net/igmp): restore General Query handling broken by pointer compare 2026-07-15 08:46:23 +02:00
openamp openamp: fix CMake dcache option 2026-05-10 15:03:24 +02:00
pass1 Makefile: Remove make depend files by make distclean 2026-02-16 16:27:57 +01:00
sched spawn: allow zero stacksize/priority to use binary loader defaults 2026-07-15 12:24:44 -03:00
syscall syscall: fcntl param3 type to uintptr_t 2026-04-27 12:01:55 -03:00
tools tools/uncrustify: Update uncrustify for better support 2026-07-17 15:00:06 -03:00
video video: fix EDID standard timing decode 2026-07-17 15:00:50 -03:00
wireless drivers/: Multiple Drivers Are Registered With World Writable - Part 2 2026-07-15 15:27:28 +08:00
.asf.yaml github: master branch protection tune. 2025-05-07 18:37:13 -05:00
.codespell-ignore-lines !boards: Remove NSH_ARCHINIT and board_app_initialize 2026-05-02 18:36:46 +08:00
.codespellrc risc-v/gd32vw55x: add GigaDevice GD32VW553 port (Wi-Fi 6) 2026-07-16 10:03:16 -03:00
.editorconfig .editorconfig: fix character encoding property specification 2025-11-28 19:12:13 +08:00
.gitignore git: Specify multiple build directories in .gitignore. 2026-05-20 03:06:58 +08:00
.gitmessage docs/contributing: Add a commit message template 2025-06-03 17:33:24 +08:00
.pre-commit-config.yaml pre-commit: enable codespell checks 2025-05-05 12:34:39 +08:00
.yamllint
AUTHORS AUTHORS: add Eren Terzioglu 2026-05-20 15:17:00 +08:00
CMakeLists.txt cmake/nuttx_toolchain.cmake: track preprocessed include deps 2026-06-04 17:22:43 +08:00
CONTRIBUTING.md contributing: Add requirement for 'Assisted-by' commit field 2026-07-12 09:42:28 +08:00
INVIOLABLES.md
Kconfig sched/misc/assert: Add CONFIG_SCHED_DUMP_TASKS and CONFIG_SCHED_DUMP_STACK 2026-06-09 08:04:54 -04:00
LICENSE libs/libdsp: Add Matrix operations 2026-07-11 14:55:59 -03:00
Makefile !boards: enforce secure ROMFS passwd and TEA key setup 2026-07-09 22:41:11 +08:00
NOTICE Remove the double blank line from source files 2022-02-20 20:10:14 +01:00
README.md ci/testing: Add MemBrowse Integration 2026-06-18 12:07:41 -03:00
ReleaseNotes Documentation: move ReleaseNotes 2023-09-26 20:41:00 +08:00

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Apache NuttX is a real-time operating system (RTOS) with an emphasis on standards compliance and small footprint. Scalable from 8-bit to 64-bit microcontroller environments, the primary governing standards in NuttX are POSIX and ANSI standards. Additional standard APIs from Unix and other common RTOSs (such as VxWorks) are adopted for functionality not available under these standards, or for functionality that is not appropriate for deeply-embedded environments (such as fork()).

For brevity, many parts of the documentation will refer to Apache NuttX as simply NuttX.

Getting Started

First time on NuttX? Read the Getting Started guide! If you don't have a board available, NuttX has its own simulator that you can run on terminal.

Documentation

You can find the current NuttX documentation on the Documentation Page.

Alternatively, you can build the documentation yourself by following the Documentation Build Instructions.

The old NuttX documentation is still available in the Apache wiki.

Supported Boards

NuttX supports a wide variety of platforms. See the full list on the Supported Platforms page.

Contributing

If you wish to contribute to the NuttX project, read the Contributing guidelines for information on Git usage, coding standard, workflow and the NuttX principles.

License

The code in this repository is under either the Apache 2 license, or a license compatible with the Apache 2 license. See the License Page for more information.