Re: Questions about QEMU exception

[Alex Bennée]

"Li, Kevin" <cnkevin@amazon.com> writes:

> Hi qemu community,
>
>  
>
> We are working on some open source project which uses qemu on mac, and we 
> have some signing process to sign
> qemu-system-x86_64.
>
> If qemu-system-x86_64 is not signed, we don’t see any problem, but after sign 
> it, we got the following error:
>
>  
>
> qemu-system-x86_64 -M none -netdev help]: stdout=\"Accelerators supported in 
> QEMU binary:\\ntcg\\nhax\\nhvf\\n\",
> stderr=\"qemu-system-x86_64: allocate 1073741824 bytes for jit buffer: 
> Invalid argument
>
>  
>
> Does anyone has clue about what change may result in this failure?

Not sure about the details but I suspect this is something to do with
the way we have to jump through hoops to allocate the code buffer on
MacOSX.

You could stick some printfs around:

  alloc_code_gen_buffer_splitwx_vmremap

and

  alloc_code_gen_buffer_anon

AIUI we have to allocate a non-executable but writable buffer for the
code and then remap an executable view of the same region to execute the
generated JIT code. Maybe being a signed binary adds more restrictions
on which OS apis can be called?

-- 
Alex Bennée