Am 05.04.2016 um 10:04 hat Richard W.M. Jones geschrieben: > On Tue, Apr 05, 2016 at 06:38:36AM +0200, Kevin Wolf wrote: > > Am 01.04.2016 um 13:20 hat Richard W.M. Jones geschrieben: > > > > > > My patch, plus the configuration and comments from your patch, > > > combined. Plus I tested it with libguestfs boot-analysis and it works > > > and is still fast. > > > > > > Integrating this so it happens automatically when the user adds > > > -kernel on x86 seems quite complicated. The only way I could do it > > > was by adding #ifdef defined(__x86_64__) etc to vl.c, which doesn't > > > seem very nice. The problem is the machine type code doesn't know > > > that you're using -kernel. > > > > I would actually find it rather surprising to get differernt BIOSes and > > therefore potentially different behaviour for -kernel and for booting > > from an image. Even if we made sure that Linux really never touches the > > parts that you disable in bios-fast.bin, remember that -kernel is not > > only for Linux, but for arbitrary kernels. > > > > Requiring an explicit -bios option like you do now seems to make most > > sense to me: The default behaves the same as a normal boot, but if you > > are one of the cases that do need that additional boot speed, you can do > > that and consciously sacrifice the features. > > OK so this reminds me of the second problem. How to detect what > bioses are available, given a qemu binary. It would be nice if qemu > had an option like: > > qemu -bios \? > > Of course we can try to scan /usr/share/qemu/bios.*, except that > Fedora installs extra ROMs in /usr/share/seabios/ (I'm not exactly > sure how qemu deals with those), and the path is different for other > distros and other qemu binaries.
At least in RHEL, /usr/share/qemu-kvm/bios.* seems to have symlinks pointing to the binaries in /usr/share/seabios/. And I would assume that that's the only directory besides the working directory where qemu looks for the files. Kevin
