Messages in this thread | | | Date | Tue, 19 Nov 2013 09:30:53 +0100 | From | Ingo Molnar <> | Subject | Re: [patch 3/3] x86, mm: get ASLR work for hugetlb mappings |
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* akpm@linux-foundation.org <akpm@linux-foundation.org> wrote:
> From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> > Subject: x86, mm: get ASLR work for hugetlb mappings > > Matthew noticed that hugetlb doesn't participate in ASLR on x86-64. The > reason is genereic hugetlb_get_unmapped_area() which is used on x86-64. > It doesn't support randomization and use bottom-up unmapped area lookup, > instead of usual top-down on x86-64. > > x86 has arch-specific hugetlb_get_unmapped_area(), but it's used only on > x86-32. > > Let's use arch-specific hugetlb_get_unmapped_area() on x86-64 too. It > fixes the issue and make hugetlb use top-down unmapped area lookup.
So the title and the changelog has typos (I counted three), which makes me wonder how well this was tested.
To show/document the testing effort a before/after /proc/PID/maps output showing hugetlb vma addresses would be nice, showing that ASLR didn't work before and that it works adequately after the patch.
A word about the range and granularity of randomization in the typical case would be nice as well.
Thanks,
Ingo
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