Re: [PATCH 00/17] pramfs: persistent and protected RAM filesystem

[Pavel Machek <pavel@ucw.cz>]

> Il 06/01/2011 19:22, Luck, Tony ha scritto:
> >> Errata corrige: maybe I used the wrong term, I meant "volatile" instead
> >> of "temporary" information, i.e. I'd like to save this info to re-read
> >> it later but I don't want to store it in flash, a simple log, run-time
> >> information for debug like a flight-recorder or whatever you want.
> > 
> > I'm puzzled by the use of "a generic piece of memory" to store "persistent"
> > things (Perhaps this is made clear in the 17 parts of the patch? I haven't
> > read them yet).  On x86 f/w typically clears all of memory on reset ... so
> > you only get persistence if you use kexec to get from the old kernel to
> > the new one.
> > 
> > -Tony
> > 
> 
> First of all, you can find a lot of information on the web site where
> there is an overview and a page with implementation details, benchmark
> and so on. With "a generic piece of memory" I mean a generic memory
> device directly addressable. Usually this generic device is an NVRAM, so
> we have a persistent store. If you haven't got this hw you can use other
> devices or the classic RAM, in this case you have a fs persistent only
> over reboot. The use of this fs is mainly for embedded systems, fw can
> be configured to not clear *all* the memory. Pramfs is indeed supported
> by U-Boot, you can see CONFIG_PRAM in the Das U-Boot manual. x86 in this
> case can be a "strange" world for this fs, but however if the user wants
> it can be used without problems because there aren't neither strict arch
> or hw dependency.

Actually you probably want to state u-boot compatibility in the commit
message. AFAICT, that is quite good argument _for_ inclusion.


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