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Date:   Thu, 21 Sep 2023 18:33:23 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Florent Revest <revest@chromium.org>
Cc:     linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        catalin.marinas@arm.com, anshuman.khandual@arm.com,
        joey.gouly@arm.com, mhocko@suse.com, keescook@chromium.org,
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        broonie@kernel.org, szabolcs.nagy@arm.com, kpsingh@kernel.org,
        gthelen@google.com, toiwoton@gmail.com, ayush.jain3@amd.com
Subject: Re: [PATCH v4 5/6] mm: Add a NO_INHERIT flag to the PR_SET_MDWE
 prctl
Message-Id: <20230921183323.c990c57d0b43832b39d3e363@linux-foundation.org>
In-Reply-To: <20230828150858.393570-6-revest@chromium.org>
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        <20230828150858.393570-6-revest@chromium.org>
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On Mon, 28 Aug 2023 17:08:57 +0200 Florent Revest <revest@chromium.org> wrote:

> This extends the current PR_SET_MDWE prctl arg with a bit to indicate
> that the process doesn't want MDWE protection to propagate to children.
> 
> To implement this no-inherit mode, the tag in current->mm->flags must be
> absent from MMF_INIT_MASK. This means that the encoding for "MDWE but
> without inherit" is different in the prctl than in the mm flags. This
> leads to a bit of bit-mangling in the prctl implementation.

Is a manpage update planned?

And did we update the manpage for PR_SET_MDWE?