Re: [PATCH 00/17] pramfs: persistent and protected RAM filesystem
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. -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line unsubscribe linux-embedded in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 00/17] pramfs: persistent and protected RAM filesystem
On Thu, 2011-01-06 at 13:00 +0100, Marco Stornelli wrote: Hi all, after several reviews is time to submit the code for mainline. Thanks to CELF to believe and support actively the project and thanks to Tim Bird. Tony Luck was also playing with something like this I believe. -- To unsubscribe from this list: send the line unsubscribe linux-embedded in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 00/17] pramfs: persistent and protected RAM filesystem
Il 06/01/2011 15:03, Peter Zijlstra ha scritto: On Thu, 2011-01-06 at 13:00 +0100, Marco Stornelli wrote: Hi all, after several reviews is time to submit the code for mainline. Thanks to CELF to believe and support actively the project and thanks to Tim Bird. Tony Luck was also playing with something like this I believe. Yes, I know. Even if the approach is different. He is trying to use a persistent space record-based and with a simple fs interface to store oops or something like this. The idea here is a little bit different, i.e. to have a place (a generic piece of memory) to write not sensible and temporary information with a complete fs structure. However we are on the same road :) Marco -- To unsubscribe from this list: send the line unsubscribe linux-embedded in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: [PATCH 00/17] pramfs: persistent and protected RAM filesystem
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 -- To unsubscribe from this list: send the line unsubscribe linux-embedded in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH 00/17] pramfs: persistent and protected RAM filesystem
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. Marco -- To unsubscribe from this list: send the line unsubscribe linux-embedded in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html