From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793199982; b=kOJnotXaOIXeZ0T4bgWDCDrxsdnAbvOZ62rvlmVrddGFRawLLGKUWZYZWsjnhrL5ri+j gKOWAYEV3z2Rq9mIWravZUZ8Qwlq0GyI06gjLqjvy+Szh9Q0C06xSn5XWKsyjlr85oOOo 63xuxCDPzR15qR4CkZ66YcM2PU5YR1gzx1l0synyvET+JQlAQJwWGD0QTXOVyf6sA4rV6 TffzGNVP3QmzmusHq33oCXbVj0Wx6J0DbC7iyT2mEGenhKtzKQ+xE3MIK7JU434X1I8aU Jw6bNXlxXB/YaNOcArZYjqJ9xnIbqg0g0RLdeiWbs8bND6xF5n2JTv8UFU2wv2Z4F+Q== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793199982; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=jc1NHj5NVrt4/jNwGZiFo0SWS3JKZ9BEwEfYFaPbfCE=; b=oUu5UfEy+kMfcNjffPhOX6/NrDRLO0b9tDwaE1aQNEp6IDQu9BIlQPdTtdOxp+A4MpSC GFAhyRH3yxISjcw25d7lqbT/uYH8mcRfINdMIwEqPCQv0EHeVoMOyXti8IP99wzzxVJCN ZD79rR/s3HjSLreIuVo8yKUsyJhZsOnc+RrHx1J/s4Jrrg/mtw/ZYH54POo35q/RgjseL eIdxtu6EFC8cqkmBqy/nyggFvRmywyDRK8InROBo2QNqU/6TcPG0PV/QHSMs95zGcnTfn wZxqtRPOYBUGOufpLL6QCWguxs76VYGmWGRTt2nMCEq1F+azmyeIFCpw8SsTe6+Vsgw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=nSMN0kNU; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BC74D606A337; Wed, 28 Oct 2026 15:06:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=nSMN0kNU Received: by smtp.kernel.org (Postfix) with ESMTPSA id E7D741F01825; Wed, 28 Oct 2026 15:06:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793199981; bh=jc1NHj5NVrt4/jNwGZiFo0SWS3JKZ9BEwEfYFaPbfCE=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=nSMN0kNUmbsSHdv9awMBVCH6qjwWaKvcGUVUjLsuOukkXyE8GaNWdnrlzGSOWPUxx nIsSj6zS3F7QsXpgAgCtNpKWs3qPXOfWQaHXjI7q8Xy8+AoZLdOW+kb2R2ariJ14KF kh39GIVq+tFgQWcEXC77GFJzfx3q8MIhkGL8UJIK+0HbuqXpIEj0zsOIpanmvlIs+I XY1CLvSbmqKiZpQM9NT3GWGDqEiJMlgHH68ERZ6/KUve1IBluVECVEYyQ6usMhvjLF 1k28ca39gz7anWHNTGkRQgyVUEHbN5YlUmHfrgIOGLQXh3xkTgFAB5SyTFIhCpCTuz s2VKrE5jIpz0Q== Date: Wed, 28 Oct 2026 15:06:19 +0000 From: Harry Yoo To: Chris Down Cc: Vlastimil Babka , Andrew Morton , Hao Li , Christoph Lameter , David Rientjes , Roman Gushchin , Kees Cook , Marco Elver , GONG Ruiqi , Jan Kiszka , Kieran Bingham , Jonathan Corbet , linux-mm@kvack.org, linux-hardening@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@meta.com Subject: Re: [PATCH 0/8] mm/slab: Support selecting slab hardening features at boot Message-ID: References: X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Hi Chris! On Tue, Oct 27, 2026 at 03:35:16PM +0800, Chris Down wrote: > Slab hardening settings are currently all build time choices. This means > that, unfortunately, hosts with different requirements end up needing > separate kernel images. Let's allow those hosts to use one image and > select each policy at boot instead. > > This series adds four new boot parameters that default to their values > from CONFIG_*: > > slab_freelist_hardened= > slab_freelist_random= > slab_buckets= > kmalloc_partition= If we end up supporting boot-time parameters for hardening, I think it should be all enabled (or disabled) by: slab_hardening=none|light|full # please feel free to suggest bertter names none: "Turn of all of them to maximize performance" light: "I'm willying to sacrifice _some_ memory and CPU for security" full: "I'm willying to sacrifice more overhead for security IMHO more fine-grained knob for each feature doesn't make much sense. -- Cheers, Harry / Hyeonggon