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There has been some light flamewar on lkml about decoding oopses
in modules (as part of the crashdump flamewar).

Now this isn't rocket science, just the markup_oops.pl script
cheaped out and didn't handle modules. But really; a flamewar
all about that?? What happened to C++ in the kernel or reading
files from inside the kernel?

This patch adds module support to markup_oops.pl; it's not the
most pretty perl but it works for my testcases...
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We're struggling all the time to figure out where the code came from that
oopsed..  The script below (a adaption from a script used by
kerneloops.org) can help developers quite a bit, at least for non-module
cases.

It works and looks like this:

[/home/arjan/linux]$ dmesg | perl scripts/markup_oops.pl vmlinux
 {
 	struct agp_memory *memory;

 	memory = agp_allocate_memory(agp_bridge, pg_count, type);
 c055c10f:	89 c2                	mov    %eax,%edx
 	if (memory == NULL)
 c055c111:	74 19                	je     c055c12c <agp_allocate_memory_wrap+0x30>
 /* This function must only be called when current_controller != NULL */
 static void agp_insert_into_pool(struct agp_memory * temp)
 {
 	struct agp_memory *prev;

 	prev = agp_fe.current_controller->pool;
 c055c113:	a1 ec dc 8f c0       	mov    0xc08fdcec,%eax
*c055c118:	8b 40 10             	mov    0x10(%eax),%eax     <----- faulting instruction

 	if (prev != NULL) {
 c055c11b:	85 c0                	test   %eax,%eax
 c055c11d:	74 05                	je     c055c124 <agp_allocate_memory_wrap+0x28>
 		prev->prev = temp;
 c055c11f:	89 50 04             	mov    %edx,0x4(%eax)
 		temp->next = prev;
 c055c122:	89 02                	mov    %eax,(%edx)
 	}
 	agp_fe.current_controller->pool = temp;
 c055c124:	a1 ec dc 8f c0       	mov    0xc08fdcec,%eax
 c055c129:	89 50 10             	mov    %edx,0x10(%eax)
 	if (memory == NULL)
 		return NULL;

 	agp_insert_into_pool(memory);

so in this case, we faulted while dereferencing agp_fe.current_controller
pointer, and we get to see exactly which function and line it affects...
Personally I find this very useful, and I can see value for having this
script in the kernel for more-than-just-me to use.

Caveats:
* It only works for oopses not-in-modules
* It only works nicely for kernels compiled with CONFIG_DEBUG_INFO
* It's not very fast.
* It only works on x86
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>