Re: debugging LKMs with GDB

[Ed L Cashin <ecashin@xxxxxxxxxx>]

aq <aquynh@xxxxxxxxx> writes:

> On Mon, 8 Nov 2004 01:04:04 +0000, Jon Masters <jonmasters@xxxxxxxxx> wrote:
>> On Sun, 7 Nov 2004 21:51:11 +0530, Shakthi Kannan <shakthimaan@xxxxxxxxx> wrote:
>> 
>> > On Sun, 7 Nov 2004 14:07:47 +0530, Himanshu Chauhan
>> > <meethimanshuchauhan@xxxxxxxxx> wrote:
>> > > As we can debug user space programs with GDB, how can we debug the
>> > > loadable kernel modules
>> > > with GDB.
>> >
>> > I believe it can be done. You can probably even use ddd (Data Display
>> > Debugger). But, you may have to pass /proc/kcore to gdb.
>> 
>> You can, but not from the same box.
>> 
>> As was mentioned by Ajey Kulkarni in an earlier post, kgdb should help
>> here - it's a patch to the kernel which allows remote debugging from a
>> second host, whereas kdb (without the g) is a built-in debugger that
>> won't give you quite the level of debug.
>> 
>> Note that Linus does not bless kernel debuggers, but he has come
>> around to understanding a use for Dprobes. Perhaps it's worth using
>> probes as an alternative to a full debugger.
>
> You misspelled it. That should be "kprobes", not Dprobes

I thought the same thing, but then I thought, "No, Jon Masters would
probably not do that."  A google later, I see...

  http://www-124.ibm.com/developerworks/oss/linux/projects/dprobes/

which says...

  DProbes basic infrastructural parts are split out as stand-alone
  patches defining new interfaces called Kprobes.

-- 
  Ed L Cashin <ecashin@xxxxxxxxxx>


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