Messages in this thread | | | Date | Wed, 1 Feb 2023 19:03:49 +0100 | Subject | Re: [PATCH v5 18/39] mm: Handle faultless write upgrades for shstk | From | David Hildenbrand <> |
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On 01.02.23 18:32, Edgecombe, Rick P wrote: > On Wed, 2023-02-01 at 10:03 +0100, David Hildenbrand wrote: >>> >>> The other problem is that one of NULL passers is not for kernel >>> memory. >>> huge_pte_mkwrite() calls pte_mkwrite(). Shadow stack memory can't >>> be >>> created with MAP_HUGETLB, so it is not needed. Using >>> pte_mkwrite_kernel() would look weird in this case, but making >>> huge_pte_mkwrite() take a VMA would be for no reason. Maybe making >>> huge_pte_mkwrite() take a VMA is the better of those two options. >>> Or >>> keep the NULL semantics... Any thoughts? >> >> Well, the reason would be consistency. From a core-mm point of view >> it >> makes sense to handle this all consistency, even if the single user >> (x86) wouldn't strictly require it right now. >> >> I'd just pass in the VMA and call it a day :) > > Ok, I'll give it a spin.
It would be good to get more opinions on that, but I'm afraid we won't get more deep down in this thread :)
-- Thanks,
David / dhildenb
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