On Tue, Feb 24, 2009 at 04:20:01PM -0500, Fred Isaman wrote: > On Tue, Feb 24, 2009 at 4:03 PM, Sam Ravnborg <sam@xxxxxxxxxxxx> wrote: > > On Tue, Feb 24, 2009 at 02:05:25PM -0500, Fred Isaman wrote: > >> The pnfs tree base of of 2.6.29-rc5 uses the new find_last_bit > >> function (defined in > >> lib/find_last_bit.c) in a file in the fs/nfs directory. Myself and > >> another developer (though no one else so far) get the following error > >> during compile: > >> > >> Kernel: arch/x86/boot/bzImage is ready (#5) > >> Building modules, stage 2. > >> MODPOST 515 modules > >> ERROR: "find_last_bit" [fs/nfs/nfs.ko] undefined! > >> make[2]: *** [__modpost] Error 1 > >> make[1]: *** [modules] Error 2 > >> make: *** [sub-make] Error 2 > >> > >> > >> Note that find_last_bit() is not used in any file in the fs directory. > >> If I add it to any function that is EXPORT_SYMBOL'ed > >> from the fs directory, suddenly the compile errors go away. (See the > >> below patch for a more concrete example.) > >> > >> I am not sure what is going on, and why it only affects some > >> developers, but it looks a lot like the kbuild system > >> is deciding that the library does not need to be included at the fs > >> directory level, so isn't including it in fs/nfs where > >> it is needed. > > > > kbuild only links in libaries if there is any users of siad library. > > And your normal config has no users of lib/find_last_bit.c so > > it is not linked into the kernel. > > > > I don't understand your comment. There *is* a user of the library in the > (modified) fs/nfs/nfs4proc.c. The problem is that it doesn't compile unless > there is also a user in some fs/*.c. There need to be an in-kernel user and I expect fs/nfs/nfs4proc.c is build as a module. Sam -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
