[prev in list] [next in list] [prev in thread] [next in thread] 

List:       linux-api
Subject:    Re: [PATCH] mm: allow checking length for hugetlb mapping in mmap()
From:       Mike Kravetz <mike.kravetz () oracle ! com>
Date:       2020-03-31 22:04:54
Message-ID: e8e8ea0b-f912-2084-ee28-d4da1968e70a () oracle ! com
[Download RAW message or body]

On 3/31/20 1:35 AM, Li Xinhai wrote:
> My understanding may wrong, but it seems that once some application start to use
> some behavior of kernel, although that usage in user space is not logical, they
> will be protected from change in kernel side.

Correct.  I too wish that the length argument to mmap for hugetlb mappings
was required to be a multiple of huge page size.  That would make everything
nice and consistent.  However, the behavior of rounding the length up to huge
page size has existed for quite some time and it well documented.  Therefore,
we can not change it without the possibility of breaking some application.

-- 
Mike Kravetz
[prev in list] [next in list] [prev in thread] [next in thread]