Re: RFC: Selecting an NVMEM cell for Power State Change Reason (PSCR) recording

[Kees Cook]

On Thu, Oct 02, 2025 at 02:00:09PM +0200, Oleksij Rempel wrote:
> I'm seeking consensus on a minimal, upstream-acceptable way to identify the
> single NVMEM cell used to persist a Power State Change Reason (PSCR). Typical
> targets are battery-backed RTC scratchpads or small EEPROM. The aim is to have
> a tiny breadcrumb available before userspace, across full power cuts, and
> shared by bootloader/kernel/userspace.
> [...]
> * pstore integration (not tried): a backend that uses a nominated NVMEM cell if
>   such a nomination is acceptable.

Several years ago I wanted to have tighter integration between pstore
and nvdimm code. The thread is here, for reference:
https://lore.kernel.org/lkml/CAGXu5jLtmb3qinZnX3rScUJLUFdf+pRDVPjy=CS4KUtW9tLHtw@xxxxxxxxxxxxxx/

I'm not sure it it'll be a useful as background, but I thought I'd
mention it. :)

-Kees

-- 
Kees Cook