Re: [PATCH 1/3] ring-buffer: Add uname to match criteria for persistent ring buffer

[Linus Torvalds]

On Tue, 17 Dec 2024 at 09:34, Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
>
> Add uname into the meta data and if the uname in the meta data from the
> previous boot does not match the uname of the current boot, then clear the
> buffer and re-initialize it.

This seems broken.

The problem is not that the previous boot data is wrong.

The problem is that you printed it *out* wrong by trying to interpret
pointers in it.

Now you basically hide that, and make it harder to see any data from a
bad kernel (since you presumably need to boot into a good kernel to do
analysis).

The real fix seems to have been your 3/3, which still prints out the
data, but stops trying to interpret the pointers in it.

Except you should also remove the last_text_delta / last_data_delta
stuff. That's all about exactly that "trying to interpret bogus
pointers". Instead you seem to have actually just *added* a case of
that in your 3/3.

           Linus