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From: Deepak Gupta <debug@rivosinc.com>
Date: Thu, 28 Mar 2024 22:15:40 -0700
Message-ID: <CAKC1njTheY9+gRFgiWaA8fG5hiOFXqESz7eGDbhHhDZC7Kignw@mail.gmail.com>
Subject: Re: [PATCH v2 11/27] riscv mmu: teach pte_mkwrite to manufacture
 shadow stack PTEs
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On Thu, Mar 28, 2024 at 9:46=E2=80=AFPM Deepak Gupta <debug@rivosinc.com> w=
rote:
>
> pte_mkwrite creates PTEs with WRITE encodings for underlying arch. Underl=
ying
> arch can have two types of writeable mappings. One that can be written us=
ing
> regular store instructions. Another one that can only be written using sp=
ecialized
> store instructions (like shadow stack stores). pte_mkwrite can select wri=
te PTE
> encoding based on VMA range.
>
> On riscv, presence of only VM_WRITE in vma->vm_flags means it's a shadow =
stack.
>
> Signed-off-by: Deepak Gupta <debug@rivosinc.com>
>
> rebase with a30f0ca0fa31cdb2ac3d24b7b5be9e3ae75f4175
>
hmm.. Note to self:
Missed removing this lingering commit message. Will remove it in the
next version.