[Qemu-devel] [BUG?] vvfat vs. pc-1.1 isa-fdc.check_media_rate=off

[Philipp Hahn]

Hello,

I tried to create a virtual VFAT floppy image on-the-fly with qemi(-kvm)-1.1.1 
using the command line argument
  -drive file=fat:floppy:"$WORK/floppy",if=floppy,index=0

Everything worked fine until I added the additional "-M pc-0.14" command line 
argument: Then I only get an empty floppy image.
I narrowed this down to the PC_COMPAT_1_0 definition in hw/pc_piix.c, which 
added
           .driver   = "isa-fdc",\
            .property = "check_media_rate",\
            .value    = "off",\
to the compat settings. If I also add an
  -global isa-fdc.check_media_rate=on
to explicitly overwrite that setting, vvfat also works with pc-1.0 and 
earlier.

I didn't unsterstand from reading the code what that flag is supposed to do, 
so can somebody give me some help to understand what goes wrong here.

I think vvfat needs to be patched to also work with check_media_rate=off.

Sincerely
Philipp
-- 
Philipp Hahn           Open Source Software Engineer      address@hidden
Univention GmbH        be open.                       fon: +49 421 22 232- 0
Mary-Somerville-Str.1  D-28359 Bremen                 fax: +49 421 22 232-99
                                                   http://www.univention.de/

signature.asc
Description: This is a digitally signed message part.