[PATCH] eal: zero out new added memory

[lic121]

On Tue, Aug 30, 2022 at 01:59:16PM +0300, Dmitry Kozlyuk wrote:
> Thank you for the most detailed info!
> 
> 1. If you run the poisoner program the second time,
>    does it also see dirty memory immediately after mmap()?

If I run the poisoner program the second time, no dirty memory.

There could be some difference on how my poisoner program and how
testpmd using mmap. Because I notice that testpmd leaves the hugepage
files under /dev/hugepage/rtemap_xxx even after testpmd exits. But my
poisoner program didn't create any file under /dev/hugepage.

> 
> 2. Kernel 4.19.90-2102 patchlevel 2102 is very high,
>    can there be any unusual patches applied?
>    Your host has "compute" in its name,
>    can it have patches that trade security for performance?

I may need to talk with the kernel team on this. Indeed, I failed to
reprouce the issue on a virtuam machine of kernel
4.18.0-305.12.1.el8_4.x86_64(2M page size instead of 1G).