[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA
From: |
Daniel P. Berrange |
Subject: |
Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable |
Date: |
Fri, 2 Oct 2015 16:24:17 +0100 |
User-agent: |
Mutt/1.5.23 (2014-03-12) |
On Fri, Oct 02, 2015 at 09:40:41AM -0400, 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?
I think it is pretty meaningless - I've always considered the use of
-kernel vs -boot / bootindex= to be mutually exclusive. I think that
libvirt leaves out -boot entirely if it adds -kernel. If the kernel
specified via -kernel doesn't boot for some reason (corrupt image
or wrong arch image or something) then I think users would reasonably
expect QEMU to not boot, rather than fallback to non-kernel boot
approach.
Regards,
Daniel
--
|: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org -o- http://virt-manager.org :|
|: http://autobuild.org -o- http://search.cpan.org/~danberr/ :|
|: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|
- Re: [Qemu-devel] [PATCH v4 3/7] Implement fw_cfg DMA interface, (continued)
- [Qemu-devel] [PATCH v4 2/7] fw_cfg DMA interface documentation, Marc Marí, 2015/10/08
- [Qemu-devel] [PATCH v4 1/7] fw_cfg: document fw_cfg_modify_iXX() update functions, Marc Marí, 2015/10/08
- [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Marc Marí, 2015/10/08
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Laszlo Ersek, 2015/10/08
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Gerd Hoffmann, 2015/10/08
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Kevin O'Connor, 2015/10/08
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Laszlo Ersek, 2015/10/08
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Gerd Hoffmann, 2015/10/08
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable,
Daniel P. Berrange <=
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Kevin O'Connor, 2015/10/08
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Laszlo Ersek, 2015/10/08
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Marc Marí, 2015/10/08
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Gerd Hoffmann, 2015/10/08
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Marc Marí, 2015/10/08
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Gerd Hoffmann, 2015/10/08
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Laszlo Ersek, 2015/10/08
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Gerd Hoffmann, 2015/10/08
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Laszlo Ersek, 2015/10/08
- Re: [Qemu-devel] [PATCH v4 6/7] Make the kernel image in the fw_cfg DMA interface bootable, Jordan Justen, 2015/10/08