From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 300673BE635; Wed, 23 Sep 2026 07:20:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790148006; cv=none; b=Pxa6GaGbQDsfJ0ngzsNGY5o79zLnznGPsgoBr5SC+IuJT9/Ck02DN0RlDGqbBB25/t1YJpKwvYeh/a7f6TKuzj+x3F/dV2kQrEa6IejEr2C0dbkAPM22UzLugf/+0DFDXWXvq3Up3ZZZ0wITNR9l5uuRMKUposSx4NJRzWGMuIg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790148006; c=relaxed/simple; bh=gziUiBPvy7xlnA9Psh/XnuMh7PkIHbeXiu+KpjWd6go=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=BhK8VliNmva2ozRkRNmD5VpDNbhwK8hm80rNj4TxIzyKbq9tV/g3BeYoMK09urSEj97hn5TYf1i0rI8EX+DLiVx6NbAL7jSHK+egrA0irKx7iA7KglKH+OQ/nq4YCH9Df8Bn65fNPjSQc2ItK9yLzfWMU0npM59mxy9w6AfHoQ8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Pjp16mZs; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Pjp16mZs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 24F2F1F000FF; Wed, 23 Sep 2026 07:19:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790147998; bh=gziUiBPvy7xlnA9Psh/XnuMh7PkIHbeXiu+KpjWd6go=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=Pjp16mZsVP5+uIktXkAWb55DfP3vzDdpoxGQASzoYolcqBMemw9oonzL8IBUYGRnk ekxdXaZVkK34HQAlc6hY2aqFH+PmdtWeo1hBB0QnDq5yilA8uUqhKxaOGoq/PJZQQp cnyVDJpmic/PRv6PaC7FkDs2PnWGVeT6AM7PvYm7BfCxZ9athTVXREu2RIp7CB8pU0 n8Z0c7LBPlb2eJmswE3Jm+jlRG71Ls2cTJwtJKVQvdzgNKpsGxmsntfxjD85mfm557 vfXzAJODkO0Qp3BJdTUAVR8W4knmv4REgN/mFN0+0h88Atr4I8A+aoFICQpSo4pRBo pXCeKZw1kkSCg== Date: Wed, 23 Sep 2026 08:19:51 +0100 From: "Lorenzo Stoakes (ARM)" To: "Vlastimil Babka (SUSE)" Cc: kernel test robot , oe-lkp@lists.linux.dev, lkp@intel.com, linux-kernel@vger.kernel.org, Andrew Morton , Daehyeon Ko <4ncienth@gmail.com>, Mike Rapoport , David Hildenbrand , Alexei Starovoitov , "David S. Miller" , Hagen Paul Pfeifer , Jakub Kacinski , James Bottomley , Jesper Dangaard Brouer , John Fastabend , "Liam R. Howlett" , Michal Hocko , Stanislav Fomichev , Suren Baghdasaryan , linux-mm@kvack.org Subject: Re: [linus:master] [mm/secretmem] 97d34aa65c: stress-ng.secretmem.ops_per_sec 99.5% regression Message-ID: References: <202609230824.7a9189aa-lkp@intel.com> <7ea6e90a-e2fb-4793-b6ea-e292388bdfdf@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7ea6e90a-e2fb-4793-b6ea-e292388bdfdf@kernel.org> On Wed, Sep 23, 2026 at 08:35:47AM +0200, Vlastimil Babka (SUSE) wrote: > On 9/23/26 03:00, kernel test robot wrote: > > > > > > Hello, > > > > kernel test robot noticed a 99.5% regression of stress-ng.secretmem.ops_per_sec on: > > > > commit: 97d34aa65c29cca85e3e9050f4c936389b38a054 ("mm/secretmem: properly account locked pages") https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master > > Well maybe there is some inefficiency that can be fixed (haven't checked) > but if it's the cost for proper accounting then so be it? I doubt creating > secretmem pages is something userspace would have to do intensively enough > to matter. Yeah, exactly. This isn't something that should be benchmarked, this is possibly the most ludicrious benchmark I've ever seen :) If establishing a secretmem region is on your hot path you have engineered your software wrong. This is effectively a security flaw so I'm afraid must remain. -- Cheers, Lorenzo