On 10/02/15 15:40, Kevin O'Connor wrote: > On Fri, Oct 02, 2015 at 10:09:17AM +0200, Gerd Hoffmann wrote: >>> - read four bytes from under the fw_cfg selector QEMU_CFG_KERNEL_SIZE >>> (0x0008), >>> - if it is zero, return -1 --> no kernel boot requested, >>> - if it is nonzero, return 0 --> which means "top priority". >>> >>> In other words, I agree with: >>> >>>> - option_rom[nb_option_roms].bootindex = 0; >>>> + option_rom[nb_option_roms].bootindex = 1; > > The bootindex in QEMU is not visible in the firmware, so if the rest > of patch 6 is dropped then the above should be dropped as well. > >> Hmm. That makes the boot order undefined for "qemu -kernel foo -device >> virtio-blk,drive=bar,bootindex=1" when using an old seabios. I don't >> think this is a good idea. > > Wouldn't that make the bootorder undefined everywhere? What does it > mean to use -kernel and specify a bootorder?
OVMF & AAVMF look at QEMU_CFG_KERNEL_SIZE first, and process the bootorder only after. (The kernel boot can fail due to various reasons, after which it makes sense to start processing the bootorder fw_cfg file.) Thanks Laszlo
