From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3A316C433E5 for ; Mon, 27 Jul 2020 17:11:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1B8B72078E for ; Mon, 27 Jul 2020 17:11:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595869880; bh=XLRy4SH6xYtcSpdHOrlqOGtGsA5ScggILcg7hMblP4k=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=zCI4KHeF2mbgth+GowhRt6xxPgV7oz7r9g2XQDEb+AeF1645PuBVifJhttjthSqJm qhUSqWgxLCFJyau5p7+uRVtKX2KWvHFXIwc0RmL2LbN9izfXhBMcaJTXrdIHWnNnD5 +NcekMAA7Go247n8EEbItTm7d2QCrQUKSfphG2OQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727844AbgG0RLT (ORCPT ); Mon, 27 Jul 2020 13:11:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:45584 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728712AbgG0RLR (ORCPT ); Mon, 27 Jul 2020 13:11:17 -0400 Received: from kernel.org (unknown [87.71.40.38]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3AAEB206E7; Mon, 27 Jul 2020 17:11:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595869877; bh=XLRy4SH6xYtcSpdHOrlqOGtGsA5ScggILcg7hMblP4k=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=RGlKfXBUd26L5XDA1ssqNMsN524ad4SB5OWposrAfAR1GqXXVCoku8j2/PxKiDDlt ZjgCXf8wWE4+IGmxJrktVr72zad9jL8jTfqjGu+VoAyYWbVCO1WDhniWv6reqEeMu8 mqapPlh3w6TjsmKchi6eYJoHQoysiCGjddWIxmbQ= Date: Mon, 27 Jul 2020 20:11:02 +0300 From: Mike Rapoport To: linux-kernel@vger.kernel.org Cc: Alexander Viro , Andrew Morton , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Catalin Marinas , Christopher Lameter , Dan Williams , Dave Hansen , Elena Reshetova , "H. Peter Anvin" , Idan Yaniv , Ingo Molnar , James Bottomley , "Kirill A. Shutemov" , Matthew Wilcox , Mike Rapoport , Michael Kerrisk , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Thomas Gleixner , Tycho Andersen , Will Deacon , linux-api@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-nvdimm@lists.01.org, linux-riscv@lists.infradead.org, x86@kernel.org Subject: Re: [PATCH v2 7/7] mm: secretmem: add ability to reserve memory at boot Message-ID: <20200727171102.GA3655207@kernel.org> References: <20200727162935.31714-1-rppt@kernel.org> <20200727162935.31714-8-rppt@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200727162935.31714-8-rppt@kernel.org> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Oops, something went wrong with the rebase, this should have been squashed into the previous patch... On Mon, Jul 27, 2020 at 07:29:35PM +0300, Mike Rapoport wrote: > From: Mike Rapoport > > Taking pages out from the direct map and bringing them back may create > undesired fragmentation and usage of the smaller pages in the direct > mapping of the physical memory. > > This can be avoided if a significantly large area of the physical memory > would be reserved for secretmem purposes at boot time. > > Add ability to reserve physical memory for secretmem at boot time using > "secretmem" kernel parameter and then use that reserved memory as a global > pool for secret memory needs. > > Signed-off-by: Mike Rapoport > --- > Documentation/admin-guide/kernel-parameters.txt | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index fb95fad81c79..6f3c2f28160f 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -4548,6 +4548,10 @@ > Format: integer between 0 and 10 > Default is 0. > > + secretmem=n[KMG] > + [KNL,BOOT] Reserve specified amount of memory to > + back mappings of secret memory. > + > skew_tick= [KNL] Offset the periodic timer tick per cpu to mitigate > xtime_lock contention on larger systems, and/or RCU lock > contention on all systems with CONFIG_MAXSMP set. > -- > 2.26.2 > -- Sincerely yours, Mike.