Apparently the bisection result from comment #1 comes from a different issue, the VGA display stays blank, can not test the floppy drive.
Bisecting using the pcbios.bin from fd646122418~, the VGA display stops working at: 345c22aa80d1f6ddfe7898f721fd1be3bccb08f1 is the first bad commit commit 345c22aa80d1f6ddfe7898f721fd1be3bccb08f1 Author: Gerd Hoffmann <kra...@redhat.com> Date: Fri Dec 18 12:01:12 2009 +0100 roms: remove option rom packing logic Now that we load the option roms via fw_cfg, we can stop copying them to the 0xc000 -> 0xe000. The patch does just that. Also the rom loader gets simplified as all remaining users of the rom loader load the bits at a fixed address so the packing and aligning logic can go away. -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1840719 Title: win98se floppy fails to boot with isapc machine Status in QEMU: New Bug description: QEMU emulator version 4.1.50 (commit 50d69ee0d) floppy image from: https://winworldpc.com/download/417d71c2-ae18-c39a-11c3-a4e284a2c3a5 $ qemu-system-i386 -M isapc -fda Windows\ 98\ Second\ Edition\ Boot.img SeaBIOS (version rel-1.12.1-0...) Booting from Floppy... Boot failed: could not read the boot disk To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1840719/+subscriptions