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From:   Xiaoming Ni <nixiaoming@huawei.com>
Subject: Re: [PATCH v2 1/1] userfaultfd/sysctl: add
 vm.unprivileged_userfaultfd
Message-ID: <3b64de85-beb4-5a07-0093-cad6e8f2a8d8@huawei.com>
Date:   Wed, 27 May 2020 14:54:13 +0800
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On Tue, Mar 19, 2019 at 11:07:22AM +0800, Peter Xu wrote:
 > Add a global sysctl knob "vm.unprivileged_userfaultfd" to control
 > whether userfaultfd is allowed by unprivileged users.  When this is
 > set to zero, only privileged users (root user, or users with the
 > CAP_SYS_PTRACE capability) will be able to use the userfaultfd
 > syscalls.

Hello
I am a bit confused about this patch, can you help to answer it.

Why the sysctl interface of fs/userfaultfd.c belongs to vm_table instead 
of fs_table ?

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=cefdca0a86be517bc390fc4541e3674b8e7803b0

Thanks
Xiaoming Ni