Breakpoint on Memory address fails with KVM

[Vish Ishaya]

Using QEMU version 0.12.50 under ubuntu Karmic x64

To reproduce the error using a floppy with a bootloder:
qemu-system-x86_64 -s -S -fda floppy.img -boot a -enable-kvm

connect with gdb:
(gdb) set arch i8086
The target architecture is assumed to be i8086
(gdb) target remote localhost:1234
Remote debugging using localhost:1234
0x0000fff0 in ?? ()
(gdb) break *0x7c00
Breakpoint 1 at 0x7c00
(gdb) continue
Continuing.

The breakpoint is not hit.

If you close qemu and start it without kvm support:

qemu-system-x86_64 -s -S -fda floppy.img -boot a

(gdb) set arch i8086
The target architecture is assumed to be i8086
(gdb) target remote localhost:1234
Remote debugging using localhost:1234
0x0000fff0 in ?? ()
(gdb) break *0x7c00
Breakpoint 1 at 0x7c00
(gdb) continue
Continuing.

Breakpoint 1, 0x00007c00 in ?? ()
(gdb)

The breakpoint is hit. If you wait until after the bootloader has been loaded into memory, you can properly set breakpoints with or without kvm enabled.

[Thomas Huth (th-huth)]

Triaging old bug tickets ... can you still reproduce this issue with the
latest version of QEMU (currently version 2.8)?

[Launchpad Janitor (janitor)]

[Expired for QEMU because there has been no activity for 60 days.]