Trouble connecting gdb to VMWare Fusion

[gerryg404]

Hi,

I'm trying to debug an OS running on VMWare Fusion but I there is something wrong. I get the "register badly formatted" error.

(gdb) file ~/anvilos/src/os/kernel/build-x86_64/anvil-knl

Load new symbol table from "/Users/gerryg/anvilos/src/os/kernel/build-x86_64/anvil-knl"? (y or n) y

Reading symbols from /Users/gerryg/anvilos/src/os/kernel/build-x86_64/anvil-knl...done.

(gdb) show arch

The target architecture is set automatically (currently i386:x86-64)

(gdb) target remote localhost:8864

Remote debugging using localhost:8864

Sending packet: $qSupported:multiprocess+;xmlRegisters=i386;qRelocInsn+#b5...Ack

Packet received:

Packet qSupported (supported-packets) is NOT supported

Sending packet: $Hg0#df...Ack

Packet received: OK

Sending packet: $?#3f...Ack

Packet received: T05thread:00000001;06:e04b00d0ffffffff;07:e80f01f0ffffffff;10:716300c0ffffffff;

Sending packet: $Hc-1#09...Ack

Packet received: E00

Sending packet: $qAttached#8f...Ack

Packet received:

Packet qAttached (query-attached) is NOT supported

Sending packet: $qOffsets#4b...Ack

Packet received:

Remote register badly formatted: T05thread:00000001;06:e04b00d0ffffffff;07:e80f01f0ffffffff;10:716300c0ffffffff;

here: ffffffff;07:e80f01f0ffffffff;10:716300c0ffffffff;

Does anyone have a suggestion about what may be wrong

thanks

Gerry

[dariusd]

Hi Gerry, and welcome to the VMware Communities!

Which version of gdb are you running?

If it's an Apple build of gdb, try launching gdb with -arch x86_64 as a command-line argument.

Either way, try an explicit set arch i386:x86-64 ... for some versions of gdb, that seems to be necessary to really kick it into 64-bit mode, even if show arch reports that it is already set to i386:x86-64.

Cheers,

--

Darius

[gerryg404]

Thanks Darius,

I tried several versions including lldb, the gdb with macports and a *-elf gdb I built myself with no luck.

I then built a *-linux-elf gdb and it works !! It seems that the packet layout is slightly different or something. What's more I have been able to fix the deadlock I had in my kernel which was the real point of the exercise.

thanks very much for taking the time to reply.

regards

Gerry