[Crash-utility] Re: BISECTED: Re: source line numbers with x86_64 modules?
Dave Anderson <anderson(a)redhat.com> writes:
Actually it's not a problem with the vmlinux file, but rather
with kernel
module object files. The crash utility has an embedded gdb module which
is invoked as "gdb vmlinux", and to get line numbers, the crash utility
simply uses the relevant built-in gdb function to get them. And line
numbers work fine with the base kernel code from the vmlinux file.
The debuginfo data of kernel modules can be subsequently added to the
crash session by doing a gdb "add-symbol-file" command for any or all
kernel modules. But getting correct line number information for kernel
modules has been a crap-shoot in the past, depending upon architecture
and/or kernel version. For example, they don't work with 2.6.9-based
RHEL4 x86_64 kernel modules, but work fine with 2.6.18-based RHEL5 x86_64
kernels.
Looking at Mike's suspect kernel patch list, I don't see anything that
would have any relationship to the issue. Perhaps there was a build tool
change during the same timeframe?
It look like Mike just built a series of kernels and had a problem,
which should preclude a tool change.
That said. Does this feature of crash work in 2.6.29? If not is
there enough interest to track this down, and fix it if it is a kernel
bug?
If we are going to be using these tools we need them working on the
latest and greatest kernels, not some weird enterprise branch, for
fuddy duddies.
Eric