On Sun, 19 Nov 2006 20:57:11 +0000 Al Viro wrote: > On Sun, Nov 19, 2006 at 11:04:33AM -0800, Randy Dunlap wrote: > > Andi Kleen wrote: > > >>>I would copy a relatively simple C implementation, like > > >>>arch/h8300/lib/checksum.c > > >>As long as the h8300 version has the same output as the x86 version. > > > > > >The trouble is that the different architecture have different output > > >for csum_partial. So you already got a bug when someone wants to move > > >file systems. > > > > > >-Andi > > > > That argues for having only one version of it (in a lib.; my preference) > > -or- Every module having its own local copy/version of it. :( > > Wrong. csum_partial() result is defined modulo 0xffff and it's basically > "whatever's convenient as intermediate for this architecture". > > reiserfs use of it is just plain broken. net/* is fine, since all > final uses are via csum_fold() or equivalents. > > Note that reiserfs use is broken in another way: it takes fixed-endian value > and feeds it to cpu_to_le32(). IOW, even if everything had literally the > same csum_partial(), the value it shits on disk would be endian-dependent. > > As for net/*, with proper types it's pretty straightforward. See > davem's net-2.6.20 for that...
OK. I guessed that there was some sanity in there somewhere (either in the provider or consumer), but apparently there's none in either place. :( --- ~Randy - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
