Hi Richard, On Wed, Aug 21, 2019 at 11:37:30PM +0200, Richard Weinberger wrote: > Gao Xiang, > > On Mon, Aug 19, 2019 at 10:45 PM Gao Xiang via Linux-erofs > <linux-erofs@xxxxxxxxxxxxxxxx> wrote: > > > struct erofs_super_block has "checksum" and "features" fields, > > > but they are not used in the source. > > > What is the plan for these? > > > > Yes, both will be used laterly (features is used for compatible > > features, we already have some incompatible features in 5.3). > > Good. :-) > I suggest to check the fields being 0 right now. > Otherwise you are in danger that they get burned if an mkfs.erofs does not > initialize the fields. Sorry... I cannot get the point... super block chksum could be a compatible feature right? which means new kernel can support it (maybe we can add a warning if such image doesn't have a chksum then when mounting) but old kernel doesn't care it. Or maybe you mean these reserved fields? I have no idea all other filesystems check these fields to 0 or not... But I think it should be used with some other flag is set rather than directly use, right? Thanks, Gao Xiang > > -- > Thanks, > //richard
