Re: [Crash-utility] Why module's global symbol cannot be displayed in crash?
Dave,
On Tue, Mar 19, 2013 at 10:31 PM, Dave Anderson <anderson(a)redhat.com> wrote:
----- Original Message -----
> Hi list,
>
> I find in current 6.1.4 crash, when load module with "mod -S",
> only module's function symbol could be parsed out.
>
> But for module's global variant, crash cannot find related symbol...
> Any idea for this?
>
Without the debuginfo data from the module.ko.debug file, crash
gets all of its module symbol data from the kernel. So it uses
what's available in the in-kernel /proc/kallsyms list plus the
information stored in each module's "struct module". The
store_module_symbols_v2() function does the work.
If "mod -[sS]" is used, then crash has access to full debuginfo data
from the module.ko.debug file. In that case, the store_load_module_symbols()
function does the work.
For current, what I saw is when I have loaded the module, only
the t or T type symbol is installed, while others like d or D type it
would not be loaded at all...
While for one symbol, I already knows its member has a specific
magic number, so that I search the memory, and find its virtual
address becomes to 0xexxxxxxx, not the 0xbfxxxxxx.
So does it mean the debuginfo in that module only has text related,
while data type are all muted, and why?...
Thanks,
Lei