If you have a different architecture than x86, I would be grateful if you could dump the output of readelf -wL <somemodule>.ko somewhere so we can see what's happening for other archs.
-wL outputs information from .debug_line section of the ELF object. Thanks, -Joel On Wed, Jan 27, 2010 at 4:24 PM, Joel Fernandes <[email protected]> wrote: > I think the problems were in the way the line information was > structured in the kernel module ELF. > > The line information of all the objects were clubbed together when > compiling for x86_64 but the starting numbers were not taken into > account. > This how the line no.s in the resulting ko ELF objects looks like for x84_64: > addr line file > 0x1 1 super.c > 0x2 2 super.c > 0x3 3 super.c > 0x1 4 balloc.c > 0x2 5 balloc.c > > As you can see, from balloc.c onwards, the addresses are reset to 1 > (instead of 0x4). > > On the other hand I've compiled for different architectures like (UML) > and the resulting ko have continugous addresses across different .o : > 0x1 1 super.c > 0x2 2 super.c > 0x3 3 super.c > 0x4 4 balloc.c > 0x5 5 balloc.c > > Looks like gdb 6.8 gets confused when the addresses are reset, but gdb > 7.0 doesn't. > > Further, gdb 6.8 works and can interpret line numbers properly when > compiling kernel modules for different architectures (other than > x86_64) so the problem is in the way line number debug info is > structured in the ko and not in gdb. > > Thanks, > -Joel > > On Wed, Jan 27, 2010 at 5:23 AM, Peter Teoh <[email protected]> wrote: >> this is interesting....i learning something new again... >> >> pardon me if i may disagree :-). >> >> i don't think it is a bug for gdb6.8 - it is a very simple >> feature....and gdb6.8 must have got right....some point in time in the >> past --> for a particular version of gcc in the past (which create the >> debuginfo). but when u move forward your gcc version, and gdb lacks >> behind too far.....there will be a mismatch problem.....developer >> cannot possibly test so many version combination....well this is >> controversial....i may be wrong..... >> >> On Fri, Jan 22, 2010 at 10:04 PM, Mulyadi Santosa >> <[email protected]> wrote: >>> On Fri, Jan 22, 2010 at 12:20 PM, Joel Fernandes <[email protected]> >>> wrote: >>>> Incase it helps some one else, I upgraded from gdb-6.8 to gdb 7.0 and >>>> the line numbers show up fine. >>> >>> hmffffff, bug in DWARF reading.... >>> >>> -- >>> regards, >>> >>> Mulyadi Santosa >>> Freelance Linux trainer and consultant >>> >>> blog: the-hydra.blogspot.com >>> training: mulyaditraining.blogspot.com >>> >>> -- >>> To unsubscribe from this list: send an email with >>> "unsubscribe kernelnewbies" to [email protected] >>> Please read the FAQ at http://kernelnewbies.org/FAQ >>> >>> >> >> >> >> -- >> Regards, >> Peter Teoh >> > -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to [email protected] Please read the FAQ at http://kernelnewbies.org/FAQ
