Hi, On Tue, Sep 26, 2017 at 1:04 PM, Mihail Abakumov <mikhail.abaku...@ispras.ru> wrote: > We made the debugger module WinDbg (like GDB) for QEMU. This is the > replacement of the remote stub in Windows kernel. Used for remote Windows > kernel debugging without debugging mode. > > WinDbg is a multipurpose debugger for the Microsoft Windows computer > operating system, distributed by Microsoft. Recent versions of WinDbg have > been and are being distributed as part of the free Debugging Tools for > Windows suite. > > How to start debugging QEMU using WinDbg: > Run QEMU with next option: > -windbg pipe:<name> > QEMU will start and pause for waiting WinDbg connection. > Run WinDbg with next options: > -b -k com:pipe,baud=115200,port=\\.\pipe\<name>,resets=0 > Wait for debugger connect to kernel. > > Note: You can add Symbol Search Path in WinDbg such as > srv*c:\tmp*http://msdl.microsoft.com/download/symbols. > > How it works: > The WinDbg debugger has the possibility of connecting to a remote debug > service (Kdsrv.exe) in the Windows kernel. Therefore, it is possible to > connect to the guest system running in the QEMU emulator. Kernel debugging is > possible only with the enabled debugging mode, may change at the same time. > Our module of WinDbg debugger for QEMU is an alternative of the remote > debugging service in the kernel. Thus, the debugger connects to the debugging > module, not to the kernel of the operating system. The module obtains all the > necessary information answering debugger requests from the QEMU emulator. At > the same time for debugging there is no need to enable debugging mode in the > kernel. This leads to hidden debugging. Our module supports all features of > WinDbg regarding remote debugging, besides interception of events and > exceptions. Only i386 is supported now.
I wanted to try this to debug a WinXP VM running on Linux from another VM on the same host. I used my usual windbg setup only instead of -serial tcp:localhost:8888 I had -windbg tcp:localhost:8888 in the QEMU command line of the debugging target and -serial tcp:localhost:8888,server,nowait for the VM running windbg, but I didn't succeed even after disabling KVM which seems to be one of the limitations. I understand that you run QEMU on Windows. Before I dig deeper, have you tried any other backend for -windbg or maybe running on a Linux host? Is it expected to work? Thank you! Ladi > --- > > Mihail Abakumov (43): > windbg: added empty windbgstub files > windbg: added windbg's KD header file > windbg: modified windbgkd.h > windbg: added '-windbg' option > windbg: added helper features > windbg: added WindbgState > windbg: added chardev > windbg: hook to wrmsr operation > windbg: handler of fs/gs register > windbg: structures for parsing data stream > windbg: parsing data stream > windbg: send data and control packets > windbg: handler of parsing context > windbg: init DBGKD_ANY_WAIT_STATE_CHANGE > windbg: sized data buffer > windbg: generate ExceptionStateChange > windbg: generate LoadSymbolsStateChange > windbg: windbg_vm_stop > windbg: implemented windbg_process_control_packet > windbg: implemented windbg_process_data_packet > windbg: implemented windbg_process_manipulate_packet > windbg: implemented kd_api_read_virtual_memory and > kd_api_read_virtual_memory > windbg: kernel's structures > windbg: implemented kd_api_get_context and kd_api_set_context > windbg: implemented kd_api_read_control_space and > kd_api_write_control_space > windbg: implemented windbg_read_context > windbg: implemented windbg_write_context > windbg: implemented windbg_read_ks_regs > windbg: implemented windbg_write_ks_regs > windbg: implemented windbg_set_sr > windbg: implemented windbg_set_dr > windbg: implemented windbg_set_dr7 > windbg: implemented windbg_hw_breakpoint_insert and > windbg_hw_breakpoint_remove > windbg: implemented kd_api_write_breakpoint and > kd_api_restore_breakpoint > windbg: debug exception subscribing > windbg: implemented kd_api_continue > windbg: implemented kd_api_read_io_space and kd_api_write_io_space > windbg: implemented kd_api_read_physical_memory and > kd_api_write_physical_memory > windbg: implemented kd_api_get_version > windbg: implemented kd_api_read_msr and kd_api_write_msr > windbg: implemented kd_api_search_memory > windbg: implemented kd_api_fill_memory > windbg: implemented kd_api_query_memory > > > Makefile.target | 5 > cpus.c | 18 > gdbstub.c | 4 > include/exec/windbgkd.h | 1030 ++++++++++++++++++++++ > include/exec/windbgstub-utils.h | 132 +++ > include/exec/windbgstub.h | 21 > include/sysemu/sysemu.h | 2 > qemu-options.hx | 8 > target/i386/misc_helper.c | 3 > vl.c | 8 > windbgstub-utils.c | 1788 > +++++++++++++++++++++++++++++++++++++++ > windbgstub.c | 464 ++++++++++ > 12 files changed, 3482 insertions(+), 1 deletion(-) > create mode 100755 include/exec/windbgkd.h > create mode 100755 include/exec/windbgstub-utils.h > create mode 100755 include/exec/windbgstub.h > create mode 100755 windbgstub-utils.c > create mode 100755 windbgstub.c > > -- > Thanks, > Mihail Abakumov
