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Date: Wed, 11 Feb 2026 06:13:55 -0800
From: Kees Cook <kees@kernel.org>
To: Jann Horn <jannh@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>,
	Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-hardening@vger.kernel.org
Subject: Re: [PATCH] fs: Keep long filenames in isolated slab buckets
Message-ID: <202602110613.7FEC92C@keescook>
References: <20260211004811.work.981-kees@kernel.org>
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On Wed, Feb 11, 2026 at 03:06:47AM +0100, Jann Horn wrote:
> Actually, looking around a bit, there really aren't that many
> allocations with __GFP_RECLAIMABLE, so this probably isn't all that
> useful for same-cache attacks. (To be clear: Anything with
> __GFP_RECLAIMABLE goes in the special kmalloc-rcl-* slabs.) Looking

Ah! Yeah, I looked right past __GFP_RECLAIMABLE. As you say, this will
keep it isolated already.

-- 
Kees Cook