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Date: Wed, 22 Nov 2023 13:35:55 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Gregory Price <gourry.memverge@gmail.com>, linux-mm@kvack.org,
 linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org,
 linux-api@vger.kernel.org, linux-arch@vger.kernel.org,
 linux-kernel@vger.kernel.org, arnd@arndb.de, tglx@linutronix.de,
 luto@kernel.org, mingo@redhat.com, bp@alien8.de,
 dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com,
 mhocko@kernel.org, tj@kernel.org, ying.huang@intel.com, Gregory Price
 <gregory.price@memverge.com>
Subject: Re: [RFC PATCH 00/11] mm/mempolicy: Make task->mempolicy externally
 modifiable via syscall and procfs
Message-Id: <20231122133555.b7fc6cdefae0395d34a4cd1c@linux-foundation.org>
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	<20231122133348.d27c09a90bce755dc1c0f251@linux-foundation.org>
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On Wed, 22 Nov 2023 13:33:48 -0800 Andrew Morton <akpm@linux-foundation.org> wrote:

> On Wed, 22 Nov 2023 16:11:49 -0500 Gregory Price <gourry.memverge@gmail.com> wrote:
> > echo "default" > /proc/pid/mempolicy
> > echo "prefer=relative:0" > /proc/pid/mempolicy
> > echo "interleave:0-3" > /proc/pid/mempolicy
> 
> What do we get when we read from this?  Please add to changelog.
> 

Also a description of the permissions for this procfs file, along with
reasoning.  If it has global readability, and there's something
interesting in there, let's show that the security implications have
been fully considered.