Re: [Qemu-devel] QEMU, self-modifying code, and Windows 7 64-bit (no KVM)

[Hulin, Patrick - 0559 - MITLL]

On 8/18/14, 1:47 PM, "Hulin, Patrick - 0559 - MITLL"
<address@hidden> wrote:

>On Aug 18, 2014, at 1:37 PM, Richard Henderson <address@hidden> wrote:
>
>>On 08/16/2014 10:21 PM, Paolo Bonzini wrote:
>>>>>Would it work to just call tb_invalidate_phys_page_range before the
>>>>>helper_ret_stb loop?
>>I doubt it.
>
>Correct. Doesn¹t work. Haven¹t fully diagnosed why, but it doesn¹t seem
>to ever hit the current_tb_modified passage if you invalidate beforehand.

Yeah - mem_io_pc doesn¹t get updated until we¹re inside io_write, so
tb_invalidate_phys_page_range thinks we¹re inside a different TB. As a
result, it¹s ³is this TB modified² check still returns false.

I¹ve attached the correct source patch for the test case as well.

selfmodify.patch
Description: selfmodify.patch

selfmodify.flat
Description: selfmodify.flat