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Date: Mon, 21 Sep 2026 16:07:21 -0700
From: Kees Cook <kees@kernel.org>
To: Jim Cromie <jim.cromie@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Lorenzo Stoakes <ljs@kernel.org>,
	Masahiro Yamada <masahiroy@kernel.org>,
	linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org,
	bpf@vger.kernel.org
Subject: Re: [PATCH 0/3] kallsyms: Accelerate symbol name lookups by ~19x
Message-ID: <202609211605.9F15E5B1@keescook>
References: <20260919-ksyms-tune-v1-0-d85c97da1a32@gmail.com>
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In-Reply-To: <20260919-ksyms-tune-v1-0-d85c97da1a32@gmail.com>

On Sat, Sep 19, 2026 at 09:58:54PM -0600, Jim Cromie wrote:
> Memory footprint: +573 KiB .rodata for kallsyms_names_offsets (191k
> symbols * 3 bytes on x86_64 defconfig), minus ~2 KiB from dropping
> kallsyms_markers[].

The speed-up is impressive, but I have to say 500KB is not exactly
trivial. It's not _huge_, but it's not small. Is the rate of symbol
lookups in the kernel high enough to justify this loss of memory?

-- 
Kees Cook