Re: [Crash-utility] Why module's global symbol cannot be displayed in crash?

----- Original Message ----- > Dave, > > On Tue, Mar 19, 2013 at 10:31 PM, Dave Anderson <anderson(a)redhat.com&gt; > 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 I have no idea. With x86/x86_64 you can see text, data and bss symbols both before and after the "mod -[sS]" command is run. Dave