Re: [Qemu-devel] [PATCH v4] Add optionrom compatible with fw_cfg DMA version

[Gerd Hoffmann]

On Di, 2016-02-02 at 12:06 +0100, Gerd Hoffmann wrote:
>   Hi,
> 
> >  %.img: %.o
> > -   $(call quiet-command,$(LD) $(LDFLAGS_NOPIE) -Ttext 0 -e _start -s -o $@ 
> > $<,"  Building $(TARGET_DIR)$@")
> > +   $(call quiet-command,$(LD) $(LDFLAGS_NOPIE) -m elf_i386 -Ttext 0 -e 
> > _start -s -o $@ $<,"  Building $(TARGET_DIR)$@")
> 
> Hmm, that breaks the windows cross build:
> 
> make: Entering directory `/home/kraxel/projects/qemu/build-win32'
>   Building optionrom/linuxboot_dma.img
> i686-w64-mingw32-ld: unrecognised emulation mode: elf_i386
> Supported emulations: i386pe
> make[1]: *** [linuxboot_dma.img] Error 1

Testing shows two more problems:

(1) initrd loading is broken, kernel complains it finds only gibberish:

[    0.934582] Unpacking initramfs...
[    1.166983] Initramfs unpacking failed: junk in compressed archive
[    1.168458] Freeing initrd memory: 32812k freed

(2) going back to non-dma boot via -M pc-$old doesn't work, appearently
    fw_cfg dma is enabled even for old machine types.

cheers,
  Gerd