Re: [Qemu-devel] [PATCH] gdbstub: Do not kill target in system emulation mode

[Jan Kiszka]

On 2013-01-22 15:04, Fabien Chouteau wrote:
> Hello Qemu folks,
> 
> I'm sorry to be (very) late, but I do not agree with this patch.
> 
> Your modification just makes the "kill" command behave like "detach", so
> why not use "detach" instead?

gdb automatically issues kill when you quite. This is where most
casualties came from.

> 
> "kill" has its own semantic and it's important to keep it. So I suggest
> we revert this patch.

Nack, see below why it does make sense now.

Jan

> 
> Regards,
> 
>> Too many VM kittens were killed since 7d03f82f81. Another one just died
>> under my fat fingers.
>>
>> When you quit a kgdb session, does the Linux kernel power off? Or when
>> you terminate gdb attached to a hardware debugger, does your board
>> vanish in space? No.
>>
>> So let's stop terminating QEMU when the gdbstub receives a kill commando
>> in system emulation mode. Real termination can still be achieved via
>> "monitor quit". We keep the behavior for user mode emulation which is
>> arguably more like a gdbserver scenario.
>>
>> Signed-off-by: Jan Kiszka <address@hidden>
>> ---
>>  gdbstub.c |    2 ++
>>  1 files changed, 2 insertions(+), 0 deletions(-)
>>
>> diff --git a/gdbstub.c b/gdbstub.c
>> index 7d470b6..ef95ac2 100644
>> --- a/gdbstub.c
>> +++ b/gdbstub.c
>> @@ -2062,9 +2062,11 @@ static int gdb_handle_packet(GDBState *s, const char 
>> *line_buf)
>>              goto unknown_command;
>>          }
>>      case 'k':
>> +#ifdef CONFIG_USER_ONLY
>>          /* Kill the target */
>>          fprintf(stderr, "\nQEMU: Terminated via GDBstub\n");
>>          exit(0);
>> +#endif
>>      case 'D':
>>          /* Detach packet */
>>          gdb_breakpoint_remove_all();
>> -- 
>> 1.7.3.4
> 

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