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=-4.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 62B45C433E0 for ; Fri, 29 Jan 2021 07:54:15 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 08C2E64E00 for ; Fri, 29 Jan 2021 07:54:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 08C2E64E00 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=eimuftFVvJOM1kYQfbln+uL9niNkurom8GgoX+SPm9Y=; b=XTtvc7wRr1Vhz0ZO4VRcrvpdQ C3/i0tbFZe6gScXU9oquzqiGN2YGlDn2DWJ0jry0spY2DHH/uH1iX+/hBmvpBLyp3G5cj+7YDtpB0 OD95B52CEag+bhGPWoVhxxkQMnLUxukE3Ey94LqtJ/KdNkJt9+FUVVMajtugu3bDFS36b6wWXBp7j uWS3wSA4unPwsAQQnNHdbb90WCl7GBYfENlE+TpjfhiJBX2pmFwO5iWFsdX7yL9AFYDs0YmPqiHjl YgLeOYZqHjW2yLoCOaaVfvT+WpI0ESI94vgJ7izrOh/7P1UyuPoGGWAkn6HHsA/V0q5tfyZsMCx83 3a1YAf3YQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l5ObX-0006xO-FR; Fri, 29 Jan 2021 07:54:07 +0000 Received: from mx2.suse.de ([195.135.220.15]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l5ObU-0006wL-ED; Fri, 29 Jan 2021 07:54:05 +0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1611906841; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=Qq/LTzApf3bN0KeQhA5voHbd39mSTuwpVJHWgFqS7tI=; b=VeS+erlQ/D0mICcn4h1apyKupa7vysv7jPuADT7gGBStXgvb2Mh94pxpNtxq3ZHFM6eVx2 AzZTdG6HodXjhRfYzr8XnVmsRMMpIlEG/g/WmygtSF5VOOokvXwPyg8PvtC3BvdtYDoTuK +Ynl/lAwL00OK4XFtLs9b+94Viv/g4c= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id AFFA7AC55; Fri, 29 Jan 2021 07:54:00 +0000 (UTC) Date: Fri, 29 Jan 2021 08:53:59 +0100 From: Michal Hocko To: James Bottomley Subject: Re: [PATCH v16 07/11] secretmem: use PMD-size pages to amortize direct map fragmentation Message-ID: References: <20210121122723.3446-1-rppt@kernel.org> <20210121122723.3446-8-rppt@kernel.org> <20210126114657.GL827@dhcp22.suse.cz> <303f348d-e494-e386-d1f5-14505b5da254@redhat.com> <20210126120823.GM827@dhcp22.suse.cz> <20210128092259.GB242749@kernel.org> <73738cda43236b5ac2714e228af362b67a712f5d.camel@linux.ibm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <73738cda43236b5ac2714e228af362b67a712f5d.camel@linux.ibm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210129_025404_598118_EFFA6C79 X-CRM114-Status: GOOD ( 16.55 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , David Hildenbrand , Peter Zijlstra , Catalin Marinas , Dave Hansen , linux-mm@kvack.org, linux-kselftest@vger.kernel.org, "H. Peter Anvin" , Christopher Lameter , Shuah Khan , Thomas Gleixner , Elena Reshetova , linux-arch@vger.kernel.org, Tycho Andersen , linux-nvdimm@lists.01.org, Will Deacon , x86@kernel.org, Matthew Wilcox , Mike Rapoport , Ingo Molnar , Michael Kerrisk , Palmer Dabbelt , Arnd Bergmann , Hagen Paul Pfeifer , Borislav Petkov , Alexander Viro , Andy Lutomirski , Paul Walmsley , "Kirill A. Shutemov" , Dan Williams , linux-arm-kernel@lists.infradead.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Palmer Dabbelt , linux-fsdevel@vger.kernel.org, Shakeel Butt , Andrew Morton , Rick Edgecombe , Roman Gushchin , Mike Rapoport Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Thu 28-01-21 13:05:02, James Bottomley wrote: > On Thu, 2021-01-28 at 14:01 +0100, Michal Hocko wrote: [...] > > I am also still not sure why this whole thing is not just a > > ramdisk/ramfs which happens to unmap its pages from the direct > > map. Wouldn't that be a much more easier model to work with? You > > would get an access control for free as well. > > The original API was a memfd which does have this access control as > well. However, the decision was made after much discussion to go with > a new system call instead. It would be really great to summarize reasoning behind that decision. Not only for those who were not part of those discussion but also for anybody who will be reading git log and want to try to understand that reasoning. Go and read 15 versions of patchset to find that out is certainly not great use of time. Thanks! -- Michal Hocko SUSE Labs _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv