Hi Qu, On Tue, Aug 20, 2019 at 02:04:46PM +0800, Qu Wenruo wrote: > [...] > > And performance is another point. > That tree-checker in btrfs is as fast/slow as CRC32. > Not sure how it would be for dm-verity, but I guess it's slower than > CRC32 if using any strong hash. Just a word, dm-verity can do simple CRC32 without hash tree in priciple as well. It is only a time problem. > > Anyway, for a RO fs, if it's relying on dm-verify then that's OK for > real-world usage. > But as a standalone fs, even it's RO, a verification layer would be a > great plus. Yes, again, it's on my schedule at least. > > At least when new student developers try fuzzed images on the fs, it > would be a good surprise other than tons of new bug reports. > > > > > > >>> > [...] > >>> > >>> Yes, we will do such a debugging tool of course. Actually Li Guifu is now > >>> developping a erofs-fuse to support old linux versions or other OSes for > >>> archiveing only use, we will base on that code to develop a better fuzzer > >>> tool as well. > >> > >> Personally speaking, debugging tool is way more important than a running > >> kernel module/fuse. > >> It's human trying to write the code, most of time is spent educating > >> code readers, thus debugging tool is way more important than dead cold code. > > > > Agree, Xiang and I have no time to developing this feature now, we are glad very much if you could help > > us to do it ;) > > In fact, since the fs is a RO fs, it could be pretty good educational > example for any fs newbies. Thus a debug tool which can show the full > metadata of the fs can really be helpful. Yes, I think EROFS will be helpful for all fs newbies to understand the basic fs concepts, and I have received contributions from some new kernel developers. And again, I will do in my spare time. I'm dedicated to playing with EROFS in my spare time (rather than only at work to maintain for our products), so I will do and don't worry about that. And I agree with Miao Xie on one word, you can join us as well for educational reason or whatever if you have some extra time... :) Thanks, Gao Xiang > > In fact, btrfs-debug-tree (now "btrfs ins dump-tree") leads my way to > btrfs, and still one of my favourite tool to debug. > > Thanks, > Qu > > > _______________________________________________ > devel mailing list > devel@xxxxxxxxxxxxxxxxxxxxxx > http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
