GSoC status Week 4

Iori YONEJI fivo.11235813 at
Wed Jul 17 22:07:04 UTC 2013


sorry for absence of contact on soc-status list.

I had term-exam at first week, so progress is not so fast but mostly as
fast as I thought at first.

I have contacted with Neel, but I realized that I must post on soc-status,
so I show you my progress I sent to Neel before, and I discuss more
detail about that below.

== Quote ==

I'm facing two task in this project.

1. to make a call chain to issue suspend command from userland to kernel
2. to rewrite abstract registers definition that I wrote before

First, about 1, I made userland simple command to issue new ioctl()*A
call through new vmmapi function, *B
but this ioctl() handler produce general protection failure every time.
This is because a struct of registers to be saved transmission goes
something mistaken, but I'm not sure how to fix it now.
So I'm reading other codes transfer a struct to userland and looking
for documents.

Secondly, about 2, I have made a virtual machine's savable registers
definition, and I'm using this in task 1 above,but it was imperfect,
so I rewrote this and mostly done.

*A ioctl(ctx->fd, VM_GET_VCPUSTATE, vmstate);
*B vm_get_allvstate(struct vmctx *ctx, struct vmstate *vmstate)

And I have these code in local repository, but I don't know how
frequently I should commit to the freebsd repository, anyways,
I will commit them if 1's transmission goes well.

== Quote end ==

About problem 1, I knew that General Protection Fault is caused at copyout()
function, but it seems a little hard to find good books that show what's
exactly going on with copyout() and copyin().
Do you know some documents about them?

Second, problem 2 is done, referring to Intel SDM Vol1. Chapter 3 and
Vol3. Chapter 24.
This registers definition is containing some 'hidden' fields of
special registers(like GDTR),
so it is a little bit depending on Intel's implementation. In the
future work with AMD's CPU,
this struct might be changed.



More information about the soc-status mailing list