Re: [Qemu-devel] [PATCH v5 4/6] memfd: add hugetlb support

[Marc-André Lureau]

Hi

----- Original Message -----
> On Mon, Oct 23, 2017 at 10:59:08AM +0100, Marc-André Lureau wrote:
> > Linux commit 749df87bd7bee5a79cef073f5d032ddb2b211de8 (v4.14-rc1)
> > added a new flag MFD_HUGETLB to memfd_create() that specify the file
> > to be created resides in the hugetlbfs filesystem.  This is the
> > generic hugetlbfs filesystem not associated with any specific mount
> > point.
> 
> How do you know and/or control what size huge pages are used,
> when the platform supports many sizes ?

>From linux commit message:
"As with other system calls that request hugetlbfs backed pages, there is
the ability to encode huge page size in the flag arguments."

I didn't add this option to memfd backend, as I don't know how generally useful 
that is, and if there is already a similar option in qemu (probably not?). It 
could be easily added later.

> 
> Regards,
> Daniel
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