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Justin Hammond c60257bcc2 arch/risc-v/eic7700x: Correct the kernel memory map.
Three faults in how the kernel maps itself.

The page pool covered the RAM disk, which the boot loader appends above
the kernel, so the BSS clear destroyed it before anything searched for it.
The pool now covers only pgram, and the RAM disk is mapped on its own
account.

The kernel data region is mapped with 2 MiB pages rather than 4 KiB ones.
Everything in it carries the same permissions, so the finer granularity
bought nothing while costing one L3 slab per 2 MiB from a pool of two.

The linker script and Kconfig describe the page pool separately and both
descriptions are used, so they now agree.  When they disagree, pages
outside the smaller of the two get a virtual address of zero and are
written through, which on this SoC lands on identity mapped low memory
rather than faulting.

Assisted-by: Claude:claude-opus-5
Signed-off-by: Justin Hammond <justin@dynam.ac>
2026-08-19 01:40:57 +08:00
.github ci: do not trigger Build on PR description edits 2026-08-16 19:08:58 -04:00
arch arch/risc-v/eic7700x: Correct the kernel memory map. 2026-08-19 01:40:57 +08:00
audio audio: limit the buffer count guard to shared ring requests 2026-08-05 07:58:53 +02:00
binfmt sched: add supplementary group IDs (setgroups/getgroups/initgroups) 2026-08-12 16:06:03 -03:00
boards boards/qemu-intel64: add python configuration 2026-08-18 11:16:06 -03:00
cmake sched,fs,docs: support setuid sudo helper 2026-08-18 15:57:52 +08:00
crypto tools: fix stale archive members surviving a Kconfig-driven CSRCS change 2026-07-28 21:26:03 -03:00
Documentation drivers/ioexpander: List the registered pins in /proc/gpio. 2026-08-19 00:46:56 +08:00
drivers drivers/ioexpander: List the registered pins in /proc/gpio. 2026-08-19 00:46:56 +08:00
dummy
fs sched,fs,docs: support setuid sudo helper 2026-08-18 15:57:52 +08:00
graphics tools: fix stale archive members surviving a Kconfig-driven CSRCS change 2026-07-28 21:26:03 -03:00
include drivers/ioexpander: List the registered pins in /proc/gpio. 2026-08-19 00:46:56 +08:00
libs libs/libc/machine/risc-v: Compare a register at a time on equal offsets. 2026-08-17 12:24:06 +02:00
mm cmake: Use NUTTX(_DIR/_BIN_DIR) instead CMAKE(_SRC_DIR/_BIN_DIR) 2026-08-09 11:13:08 -03:00
net net/arp: do not resolve an address to another interface's MAC 2026-08-17 11:28:45 +08:00
openamp cmake: Use NUTTX(_DIR/_BIN_DIR) instead CMAKE(_SRC_DIR/_BIN_DIR) 2026-08-09 11:13:08 -03:00
pass1 tools: fix stale archive members surviving a Kconfig-driven CSRCS change 2026-07-28 21:26:03 -03:00
sched sched,fs,docs: support setuid sudo helper 2026-08-18 15:57:52 +08:00
syscall sched: add supplementary group IDs (setgroups/getgroups/initgroups) 2026-08-12 16:06:03 -03:00
tools sched,fs,docs: support setuid sudo helper 2026-08-18 15:57:52 +08:00
video tools: fix stale archive members surviving a Kconfig-driven CSRCS change 2026-07-28 21:26:03 -03:00
wireless wireless/bluetooth/bt_hcicore.c: Balance conn and buffer refs in hci_acl(). 2026-08-15 11:51:19 +08:00
.asf.yaml github: master branch protection tune. 2025-05-07 18:37:13 -05:00
.codespell-ignore-lines arch/arm: Reserve r10 via ARCHCFLAGS and hoist the PIC module flags. 2026-07-24 23:09:08 +08:00
.codespellrc arch/arm/rp23xx: Add hardware TRNG driver for /dev/random. 2026-07-25 15:06:56 +08:00
.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 Revert "cmake: normalize .config on reconfigure" 2026-08-13 07:54:00 +02:00
CONTRIBUTING.md contributing: Add requirement for 'Assisted-by' commit field 2026-07-12 09:42:28 +08:00
INVIOLABLES.md
Kconfig drivers/clk: Add debug output levels. 2026-08-16 23:23:04 +08:00
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
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.