Hi Yinghai,

> >> Can you get a boot log with "debug memblock=debug" from the last
> >> successful commit point?  Are you booting EFI or BootCamp?
> >
> > Attached the dmesg log, booting from f763ad1 which is on top of
> > 3.7-rc6. I am booting with EFI_STUB, straight into the kernel.
> > The command line and modules are built in.
> 
> will check that EFI_STUB path.
> 
> Can you check bootloader like grub.efi ?

I checked, same story. I tried without EFI_STUB, no joy. I ran with
and without nouveau, just in case. Without the patch, everything
works. With the patch, nothing works, and no output at all.

With a bit of luck, I could maybe get the first lines of output using
grub.efi, but frankly I cannot remember if that ever worked on this
machine.

Henrik