Re: [PATCH v3 2/3] docs: watchdog: npcm: Add reset status description

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] The watchdog driver abuses standard Watchdog UAPI constants to report non-watchdog platform reset causes, violating the userspace ABI contract.
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commit 72fd6c8b87d96376853f3dcd5ef1597495cf9817
Author: Tomer Maimon <tmaimon77@gmail.com>

docs: watchdog: npcm: Add reset status description

Add documentation describing how the NPCM watchdog driver reports reset
causes through bootstatus on NPCM750 and NPCM845 systems.

> diff --git a/Documentation/watchdog/npcm_wdt.rst b/Documentation/watchdog/npcm_wdt.rst
> new file mode 100644
> index 0000000000000..cdc45ade9e0d9
> --- /dev/null
> +++ b/Documentation/watchdog/npcm_wdt.rst

[ ... ]

> +.. list-table:: Reset-cause mapping
> +   :header-rows: 1
> +
> +   * - Platform
> +     - Reset indication
> +     - Bootstatus flag
> +     - Reported meaning
> +   * - NPCM750 and NPCM845
> +     - ``PORST``
> +     - ``WDIOF_OVERHEAT``
> +     - power-on reset
> +   * - NPCM750 and NPCM845
> +     - ``CORST``
> +     - ``WDIOF_FANFAULT``
> +     - core reset

[Severity: High]
Is it correct to map generic Watchdog UAPI thermal and fan failure flags to
standard platform reset indications?

The generic Watchdog API defines strict semantics for its status flags.
For instance, WDIOF_OVERHEAT means a reset due to CPU overheat, and
WDIOF_FANFAULT means a fan failed. By mapping standard SoC reset causes like
Power-On Reset (PORST) to WDIOF_OVERHEAT and Core Reset (CORST) to
WDIOF_FANFAULT, might this break the userspace ABI contract?

During a normal cold boot, reading the SoC latch would unconditionally expose
this to userspace via the WDIOC_GETBOOTSTATUS ioctl or sysfs. Standard
userspace monitoring daemons (like systemd or wdctl) reading bootstatus
might erroneously conclude the system suffered a thermal event or fan failure,
potentially triggering unintended emergency actions or false alarms.

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Sashiko AI review · https://sashiko.dev/#/patchset/20260705140100.1543486-1-tmaimon77@gmail.com?part=2