Re: [PATCH] Pseudo-console for capture and redirection of console output

[Marco Stornelli <marco.stornelli@gmail.com>]

2010/4/12 David VomLehn <dvomlehn@cisco.com>:
> Provide functions for capturing console output for storage. The primary user
> is likely to be embedded systems that don't have the storage for core dumps
> but do have a need to log kernel panic information for later evaluation. It
> offers two main areas of functionality:
>
> o       It can maintain a circular log of console output so that kernel log
>        messages written before panic() was called can be retrieved to be
>        added to the failure log.
> o       A function can be registered to store output from printk() in a
>        persistent location, such as a reserved location in RAM.  Then,
>        printk() can be used either directly, to print state information, or
>        indirectly, through standard functions like dump_stack() and
>        show_regs().
>
> During normal operation, we use the circular logging. When we crash, almost
> the first thing we do is to switch to storing output. This goes in a memory
> buffer that is preserved over reboots. We then write a detailed crash
> report using printk() and functions that use printk(). We retrieve the last
> n lines of the log before the crash and print it, so that gets captured
> in the log, too.
>

It's very similar to my driver ramoops, have you already seen it?
Currently it's in the mm tree, I think it will be included in mainline
early.

Marco