Re: [PATCH v3 0/6] allow ramoops to collect all kmesg_dump events

[Petr Mladek]

On Tue 2020-05-12 11:45:54, Kees Cook wrote:
> Here are the problems I see being solved by this:
> 
> - lifting kmsg dump reason filtering out of the individual pstore
>   backends and making it part of the "infrastructure", so that
>   there is a central place to set expectations. Right now there
>   is a mix of explicit and implicit kmsg dump handling:
> 
>   - arch/powerpc/kernel/nvram_64.c has a hard-coded list

It handles restart, halt, poweroff the same way.  I wonder if anyone
would want to distinguish them.

>   - drivers/firmware/efi/efi-pstore.c doesn't expect anything but
>     OOPS and PANIC.
>   - drivers/mtd/mtdoops.c tries to filter using its own dump_oops
>     and doesn't expect anything but OOPS and PANIC.
>   - fs/pstore/ram.c: has a hard-coded list and uses its own
>     dump_oops.
>   - drivers/mtd/mtdpstore.c (under development[3]) expected only
>     OOPS and PANIC and had its own dump_oops.

The others handle only panic or oops.

What about splitting the reason into two variables? One for severity
and other for shutdown behavior. I mean:

  + reason: panic, oops, emergency, shutdown    (ordered by severity)
  + handling: restart, halt, poweroff

Or we might just replace KMSG_DUMP_RESTART, KMSG_DUMP_HALT,
KMSG_DUMP_POWEROFF with a single KMSG_DUMP_SHUTDOWN.

Then the max reason variable would make sense.

Best Regards,
Petr