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From:   Jeff Xu <jeffxu@google.com>
Date:   Wed, 18 Oct 2023 12:07:10 -0700
Message-ID: <CALmYWFssV_nqOBKR0=8ka8vOP2v__8Nx_dL_kLs53W_RbYXViQ@mail.gmail.com>
Subject: Re: [RFC PATCH v2 5/8] mseal: Check seal flag for munmap(2)
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     jeffxu@chromium.org, akpm@linux-foundation.org,
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On Wed, Oct 18, 2023 at 11:27=E2=80=AFAM Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> On Wed, 18 Oct 2023 at 10:14, Jeff Xu <jeffxu@google.com> wrote:
> This is simply not up for discussion. Any flag for "ignore sealing" is wr=
ong.
>
> We do have one special "unmap" case, namely "unmap_vmas()' called at
> last mmput() -> __mmput() -> exit_mmap().
>
> And yes, that is called at munmap() time too, but that's after the
> point of no return after we've already removed the vma's from the VM
> lists. So it's long after any error cases have been checked.
>
Ah. I see.
I didn't know there was no legit case, which is what I worried about before=
.
this flag can be removed.