From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-lf1-f43.google.com (mail-lf1-f43.google.com [209.85.167.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 906403FE3 for ; Mon, 31 Jan 2022 23:44:02 +0000 (UTC) Received: by mail-lf1-f43.google.com with SMTP id u14so30159364lfo.11 for ; Mon, 31 Jan 2022 15:44:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=shutemov-name.20210112.gappssmtp.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=+h8DeuUfkcjLos3BviUGDVOpxtzirtyuHipEzyipWwg=; b=LEHAp+tjvjupiksn3rRU+MTYTYJP1zmZug2s1ZZldzoTJGpYo9m+xIPjubK2rtcde8 GPVx0URubvo/jJvle5RTJhnlLC6JqkPwVNpFtC6I83045f95Guvh3joXjYsjHykGAlhq 92OP3IdGZsIVkSJitzv8T5+TJfntyXg5hJSlvUP6BKmhR65VEndbO031zvU3CMnXmYk9 37chJ05w0IkvWVqNAA3kZqvLNIDXrV27x1B83Wu+CnJ9lk9O+BCi95z2rkMNtZXgJub7 vR4PpZz9noMFzfCD8iynifIes6TpoGPVFMyIInGkSWaFrJWp7gVEPpedEqol12ZjoTY0 Ef8g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=+h8DeuUfkcjLos3BviUGDVOpxtzirtyuHipEzyipWwg=; b=KEdfpIZHF5S2ZgCAQYAA41xp90tsA7pgNYMV4Rv6a0fgQpZFlb6jkoG/4wGMFva4ox RXptO4RFxRDZlQCj/xmF3ghJ/l8lSg/bZmzUkQNgk3p3FRV4gRtOVgIGwXGWKNbRTUW6 iymBScYRuKyNVdNmgV24Roa21E1ZB6f9fpB66kZu9hTdTh4zHUEYvkO7Cnt81MKuvaMp HOJ8CH5JyJxvqNacwrClklbRk75z5Kqt+zDS9xZTEb7voEiDUDAKNNTf55aPfyHfkign Y9eKmTsLNKIjsx3MnTCwK6g25bjKxRqJRQkQg5yVM68ZVf8R6YZsI2ro+3wp63N01gnA eb4A== X-Gm-Message-State: AOAM5302+WSLb5RQBWmyJsAeGC6IrBgICwMeodsXPnUuJnehxt0zgJTG s6dVPmYBnqPLidVIeKkfMX6/lQ== X-Google-Smtp-Source: ABdhPJy9muQCEl5VEBzDXlXUJUJcCiNqcoX+SUeTK/d+sBX/xKeTfWiTXJNIQJsO4DDl7bWle3JZBg== X-Received: by 2002:a05:6512:1116:: with SMTP id l22mr16771617lfg.219.1643672640599; Mon, 31 Jan 2022 15:44:00 -0800 (PST) Received: from box.localdomain ([86.57.175.117]) by smtp.gmail.com with ESMTPSA id m12sm3812652lfj.90.2022.01.31.15.43.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 31 Jan 2022 15:43:59 -0800 (PST) Received: by box.localdomain (Postfix, from userid 1000) id 5452110458C; Tue, 1 Feb 2022 02:44:37 +0300 (+03) Date: Tue, 1 Feb 2022 02:44:37 +0300 From: "Kirill A. Shutemov" To: Dave Hansen Cc: "Kirill A. Shutemov" , Borislav Petkov , Andy Lutomirski , Sean Christopherson , Andrew Morton , Joerg Roedel , Ard Biesheuvel , Andi Kleen , Kuppuswamy Sathyanarayanan , David Rientjes , Vlastimil Babka , Tom Lendacky , Thomas Gleixner , Peter Zijlstra , Paolo Bonzini , Ingo Molnar , Varad Gautam , Dario Faggioli , Brijesh Singh , Mike Rapoport , David Hildenbrand , x86@kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCHv3 2/7] efi/x86: Get full memory map in allocate_e820() Message-ID: <20220131234437.twazkxvsdukhq2xs@box.shutemov.name> References: <20220128205906.27503-1-kirill.shutemov@linux.intel.com> <20220128205906.27503-3-kirill.shutemov@linux.intel.com> <101a4497-ae17-ab69-640d-667c79da639b@intel.com> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <101a4497-ae17-ab69-640d-667c79da639b@intel.com> On Mon, Jan 31, 2022 at 02:38:42PM -0800, Dave Hansen wrote: > On 1/28/22 12:59, Kirill A. Shutemov wrote: > > Modify allocate_e820() to get a full memory map. > > Dumb question time: why doesn't the current code get a full memory map? > This looks simpler. What's the downside? Memory consumption? Yeah, it requires memory allocation that has to be freed back. Otherwise I don't see any downsides. There are several more EFI calls, but it should not make a noticable difference on boot time. -- Kirill A. Shutemov