Ubuntu
qemu-kvm package

  1. Bug #901944
  2. Comment #10

Comment 10 for bug 901944

Revision history for this message
Horst Schirmeier (horst) wrote :

I'm seeing the very same problem, please reopen.

Ubuntu 12.10 amd64 (Linux 3.5.0-25-generic x86_64), qemu-kvm 1.2.0+noroms-0ubuntu2.12.10.3. Guest is an i386 eCos test kernel (I can attach it if necessary; I guess you can use anything bootable here), started either via
 qemu-system-i386 -kernel ecos.elf -s -S
or via an ISO image with grub2:
 qemu-system-i386 -cdrom ecos.iso -s -S

I'm attaching GDB with:
 gdb ecos.elf
(gdb) target remote localhost:1234
(gdb) b main
(gdb) c
The breakpoint never hits, although this perfectly works on my 32-bit Debian Squeeze box.

If I start qemu-system-i386 with "-machine accel=tcg", the breakpoint matches very quickly, kvm halts, and the GDB prompt allows me to inspect the state. If I start qemu-system-i386 with "-machine accel=kvm" (the default), I observe the aforementioned behaviour.