On 2013-01-23 19:04, Fabien Chouteau wrote: > On 01/22/2013 03:59 PM, Jan Kiszka wrote: >> 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. > > Hello Jan, > > I asked Joel Brobecker(CC'd), a Gdb maintainer, about this issue. Here > is the answer: > > On 01/23/2013 12:49 PM, Joel Brobecker wrote: >>> There's a patch in Qemu's Gdb remote server that makes the "kill" >>> command act like "detach". >> >> It seems incorrect to me. The behavior should be as follow: >> - If the debugger was attached to an existing process, the "quit" >> command should result in a "detach". >> - If the debugger created the process, then "quit" should result >> in a "kill". >> >> With that in mind, if GDB sends a "kill", it means that Qemu told >> GDB that it created the process. What it should be doing, if a "kill" >> is not the desired behavior, is to tell GDB that the process was >> attached to. For this, there is qAttached packet. See the GDB >> Users Manual, and in particular: >> >> | `qAttached:pid' >> | Return an indication of whether the remote server attached to an >> | existing process or created a new process. When the multiprocess >> | protocol extensions are supported (see multiprocess extensions), pid is >> | an integer in hexadecimal format identifying the target process. >> | Otherwise, gdb will omit the pid field and the query packet will be >> | simplified as `qAttached'. This query is used, for example, to know >> | whether the remote process should be detached or killed when a gdb >> | session is ended with the quit command. >> | >> | Reply: >> | >> | `1' >> | The remote server attached to an existing process. >> | `0' >> | The remote server created a new process. >> | `E NN' >> | A badly formed request or an error was encountered. > > qAttached is not supported in Qemu yet, this explains why Gdb sends > "kill" at the end of debug session. I will implement it and revert your > patch. Gdb will automatically detach instead of kill at the end of > debugging session. > > Is that OK?
Sounds reasonable. Thanks, Jan PS: If you are looking for kill in the meantime: "monitor quit" -- Siemens AG, Corporate Technology, CT RTC ITP SDP-DE Corporate Competence Center Embedded Linux
