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Date: Mon, 25 Mar 2024 16:13:56 -0700
From: Kees Cook <keescook@chromium.org>
To: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Vlastimil Babka <vbabka@suse.cz>, Christoph Lameter <cl@linux.com>,
	Pekka Enberg <penberg@kernel.org>,
	David Rientjes <rientjes@google.com>,
	Joonsoo Kim <iamjoonsoo.kim@lge.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Roman Gushchin <roman.gushchin@linux.dev>,
	Hyeonggon Yoo <42.hyeyoo@gmail.com>, linux-mm@kvack.org,
	"GONG, Ruiqi" <gongruiqi@huaweicloud.com>,
	Xiu Jianfeng <xiujianfeng@huawei.com>,
	Suren Baghdasaryan <surenb@google.com>,
	Jann Horn <jannh@google.com>, Matteo Rizzo <matteorizzo@google.com>,
	linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: [PATCH v2 4/9] slab: Introduce kmem_buckets_create()
Message-ID: <202403251609.1F681B5D@keescook>
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On Mon, Mar 25, 2024 at 05:49:49PM -0400, Kent Overstreet wrote:
> The codetags are in their own dedicated elf sections already, so if you
> put the kmem_buckets in the codetag the entire elf section can be
> discarded if it's not in use.

Gotcha. Yeah, sounds good. Once codetags and this series land, I can
start working on making the per-site series.

> "usercopy window"? You're now annotating which data can be copied to
> userspace?

Hm? Yes. That's been there for over 7 years. :) It's just that it was only
meaningful for kmem_cache_create() users, since the proposed GFP_USERCOPY
for kmalloc() never landed[1].

-Kees

[1] https://lore.kernel.org/lkml/1497915397-93805-23-git-send-email-keescook@chromium.org/

-- 
Kees Cook