On Wed, Aug 07, 2013 at 07:58:18PM -0400, Kevin O'Connor wrote: > On Wed, Aug 07, 2013 at 05:53:12PM +0300, Michael S. Tsirkin wrote: > > On Wed, Aug 07, 2013 at 04:21:44PM +0200, Gerd Hoffmann wrote: > > > On 08/07/13 14:35, Michael S. Tsirkin wrote: > > > > On Wed, Aug 07, 2013 at 02:15:14PM +0200, Gerd Hoffmann wrote: > > > >> qemu doesn't error out though, so what is the point? > > > > > > > > The point is management can set the size according > > > > to the type of guest that will be installed. > > > > You can misconfigure qemu in a variety of ways > > > > and not all of them cause it to error out. > > > > > > Then seabios will still panic. I fail to see how pci-info makes things > > > more user-friendly as you've claimed a few mails back. > > > No doubt about the need to configure the 64bit window size. > > > > We need to fix it not to panic, but we put the user in control since > > windows size can now come from user. > > I'm confused. Why would seabios panic?
Question is, what to do if we can't fit all BARs into the range supplied by QEMU? > > > > And then it will have exactly the same issue if you misconfigure it. > > > > The 64bit hole size is the only thing that crashes old windows. > > > > So if you want that, then what's your problem with pci-info really? > > > > > > pci-info it has stuff which shouldn't be there IMO. > > > > > > > > > It is the job of the firmware to initialize the hardware. IMO it should > > > work that way on qemu too to mimic real hardware. > > > > That's exactly what we have. However QEMU is the one that knows > > how hardware is configured (e.g. where's the > > PCI hole), so we report that to bios. > > It was my understanding that the PCI hole size is determined by > hardware, and thus it makes sense for QEMU to send this to seabios. > (If not the hardware itself, the memory controller configuration, > which is effectively the same thing as we wont be adding full > emulation of a memory controller to qemu/seabios.) Correct me if I'm > wrong. This is certainly true for PIIX. It's more complicated for Q35 since the hole start address is configurable by firmware. Gerd refers to mch_setup in src/pciinit.c > Also, I don't understand the underlying reason for this patch. If a > user asks to start QEMU with a PCI device with a very large BAR, then > winxp wont work. But, if a user put a real PCI device with a very > large BAR in a real computer then they'd get the same failure. Why is > this a qemu/seabios issue - shouldn't the user simply not do this? > > -Kevin Sure. But if we can find a simple low risk way to make winXP not allocate resources rather than crash, that's a bit nicer, isn't it? -- MST _______________________________________________ SeaBIOS mailing list [email protected] http://www.seabios.org/mailman/listinfo/seabios
