Hi, 

I'm testing the linux-next tree and I got this stack:

[    2.158054] Call Trace:
[    2.158058]  [<ffffffff812b9159>] dump_stack+0x4b/0x72
[    2.158061]  [<ffffffff81074e62>] warn_slowpath_common+0x82/0xc0
[    2.158063]  [<ffffffff81074faa>] warn_slowpath_null+0x1a/0x20
[    2.158066]  [<ffffffffa0572291>] drm_dev_alloc+0x251/0x320 [drm]
[    2.158070]  [<ffffffffa0574d0b>] drm_get_pci_dev+0x3b/0x1e0 [drm]
[    2.158081]  [<ffffffffa07062d4>] i915_pci_probe+0x34/0x50 [i915]

How is the best way to debug this ? I really need to add a print, compile and boot many times ? 
How would you guys debug this ? 

I know a way to boot two kernels, and the second get the dump from the first. But this isn't a Oops or Panic, it's just a warning. So the second kernel will not be triggered. 

Tips ?

Thanks

--
Lucas Tanure 
+55 (19) 988176559