On 02/14/2018 04:00 PM, Alistair Francis wrote: > On Mon, Jan 15, 2018 at 4:59 AM, Stefan Hajnoczi <stefanha@xxxxxxxxx> wrote: >> On Thu, Jan 11, 2018 at 03:25:56PM -0800, Alistair Francis wrote: >>> On Wed, Jan 10, 2018 at 4:52 AM, Stefan Hajnoczi <stefanha@xxxxxxxxx> wrote: >>>> On Tue, Jan 9, 2018 at 9:45 PM, Alistair Francis <alistair23@xxxxxxxxx> wrote: >>>>> Can anyone who has done this before chime in. >>>>> >>>>> What do you think about getting someone to cleanup and improve the GDB >>>>> support in QEMU? Would that be the right difficulty of task for a GSoC >>>>> project? >>>> >>>> There is not enough information to give feedback on whether this >>>> project idea is suitable. What are the specific tasks you'd like the >>>> student to work on? >>>> >>>> In general, I'm sure there are well-defined 12-week project ideas >>>> around the GDB stub. New features are easy to propose and are usually >>>> well-defined (e.g. implement these commands that are documented in the >>>> GDB protocol documentation). Cleaning up code is less clear and it >>>> would depend on exactly what needs to be done. Interns will not have >>>> a background in the QEMU codebase and may not be able to make >>>> judgements about how to structure things, so I would be more careful >>>> about refactoring/cleanup projects. >>>> >>>> Please see my talk about QEMU GSoC for guidelines on project ideas: >>>> https://www.youtube.com/watch?v=xNVCX7YMUL8&t=19m11s >>>> http://vmsplice.net/~stefan/stefanha-kvm-forum-2016.pdf >>> >>> That helps a lot, thanks for that. >>> >>> So for a more concrete solution, how would adding support for multi >>> CPU support to the GDB server sound? >>> >>> This would allow GDB debugging for the A53 and the R5 on the Xilinx >>> ZynqMP for example. This is something we have in the Xilinx tree, but >>> it is in no state to go upstream and really needs to be re-write to be >>> upstreamable and more generic. >> >> Excellent. Then they'll already have an idea of "how" it can be >> achieved but have the freedom to write code that is most suitable for >> upstream. That is a good starting point for a project. >> >> Here is the project idea template: >> >> === TITLE === >> >> '''Summary:''' Short description of the project >> >> Detailed description of the project. >> >> '''Links:''' >> * Wiki links to relevant material >> * External links to mailing lists or web sites >> >> '''Details:''' >> * Skill level: beginner or intermediate or advanced >> * Language: C >> * Mentor: Email address and IRC nick >> * Suggested by: Person who suggested the idea >> >> Once you have written down the project idea, please post it under >> Internships/ProjectIdeas/MultiCPUGDBStub and then add it to the >> Google_Summer_of_Code_2018 wiki page using the >> "{{:Internships/ProjectIdeas/MultiCPUGDBStub}}" inlining syntax. >> >> Or if you prefer, just reply with the project idea to this email and >> I'll post it on the wiki for you. >> >> Can you think of a co-mentor who would be willing to participate? It >> makes internships easier when there are multiple mentors - less stress >> for mentors, faster communication for students. > > Yep, here is my proposal. I don't have wiki access, so I can't add it myself. > > I think Philippe would be a good co-mentor, if he is happy to. I am > also welcome to mentor other ideas, it doesn't have to be this one. I'm very happy to co-mentor with Alistair, I can manage at least 2h/w on it. > > === Multi-CPU cluster support for GDB server in QEMU === > > There are many examples in modern computing where multiple CPU > clusters are grouped together in a single SoC. This is common in the > ARM world especially. There are numerous examples such as ARM's > big.LITTLE implementations and Xilinx's 4xA53s and 2xR5s on the ZynqMP > SoC. The goal of this task is to add support to the GDB server to > allow users to debug across these clusters. > > This is another step towards single binary QEMU as well. > > Detailed description of the project. > > Xilinx has an out of tree implementation that can be used as a > starting point. Work will need to be done on top of this to prepare it > for upstream submission and to ensure the implementation is more > generic. > > This will mostly involve extending GDB server to tell GDB about > different architectures and then allow the user to swap between them. > > The Xilinx implementation can be seen here: > https://github.com/Xilinx/qemu/blob/master/gdbstub.c > There has been some steps in preparing the work to go upstream, which > can be seen here: > https://github.com/Xilinx/qemu/tree/mainline/alistair/gdb > > '''Details:''' > * Skill level: advanced > * Language: C > * Mentor: alistair23@xxxxxxxxx, Philippe? > * Suggested by: Alistair Francis > >> >> Stefan
