From nobody Tue Nov 26 20:36:36 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass(p=none dis=none) header.from=linaro.org ARC-Seal: i=1; a=rsa-sha256; t=1705418087; cv=none; d=zohomail.com; s=zohoarc; b=EovE3AG5zzrPemzcPz5OGSuuiwufaBdrFRWgJMOgoCAFV7Z/uoXh8O5bCaBc6g8ogmoYLFRMuT0fv6Y8hMJY6uPRYn8rsfbqlj9w6gwfU+pN/+yCumTWQFAtgidjP1Alk1tgCosUxiZ0oorqlcEjs9I7ZewVhh+nRR8BtERw03g= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1705418087; h=Content-Type:Content-Transfer-Encoding:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:Subject:To:To:Message-Id:Reply-To:Cc; bh=SScbRSdHLdETXW89TnfIltt7SofqN6SCYQfgIoU2I1c=; b=Uc5zfuorU8ARCY6rCnFU3+86TaIOlccVKX0qGWxFtp9JhKE3Dr5aXv0rXigZ/BK5x2umgthE5ULZu9Sfmtu1qj4ljj35ToVZt8RMKnU+dDNT0hCuK3V2Qk6ar7/CcRVOQZiJvqK6k4jpqcCot4apRPPmycVghlFnuyWwx1kkiS4= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=pass header.from= (p=none dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 170541808704615.394404648821933; Tue, 16 Jan 2024 07:14:47 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rPl7G-0006co-C6; Tue, 16 Jan 2024 10:12:38 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rPl7D-0006bZ-TM for qemu-devel@nongnu.org; Tue, 16 Jan 2024 10:12:35 -0500 Received: from mail-wm1-x330.google.com ([2a00:1450:4864:20::330]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1rPl79-0005pK-Pr for qemu-devel@nongnu.org; Tue, 16 Jan 2024 10:12:35 -0500 Received: by mail-wm1-x330.google.com with SMTP id 5b1f17b1804b1-40e87d07c07so42245e9.1 for ; Tue, 16 Jan 2024 07:12:31 -0800 (PST) Received: from orth.archaic.org.uk (orth.archaic.org.uk. [2001:8b0:1d0::2]) by smtp.gmail.com with ESMTPSA id m14-20020adff38e000000b003379b549a00sm10091357wro.10.2024.01.16.07.12.30 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 16 Jan 2024 07:12:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1705417950; x=1706022750; darn=nongnu.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:from:to:cc:subject:date:message-id :reply-to; bh=SScbRSdHLdETXW89TnfIltt7SofqN6SCYQfgIoU2I1c=; b=fkFL6fgYGoqdpj1M3XCbWMUOj/dewlaH7TMK8xUh8We8BX3JJKb28NpLdAVh0zeodf jfHu4fHBSGE/OUPzxN4QALS1RHLGk2PYy5qsnTBuj5vA1c395JzYG5lq3dVSx5fvVb47 5qDQa5Lh37jyOCPlZozadpRf2UnSGCWRPLpcLwQq8LtyZys40EtiaAtgmEhbuhUzD0du DJsYKxEHxqU0duHmg/aHaPRP2+IZvhqecaNPUm3z7EXvBplq+chb4Zu1ey6XYqcty8l3 CGTWZdg4to5B1iQGV3UxgZf5zKFgxGEtWvgZWoJaxgTNAQ43DsFd5e997JuW8251R6qu FxWA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1705417950; x=1706022750; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=SScbRSdHLdETXW89TnfIltt7SofqN6SCYQfgIoU2I1c=; b=hqS4y5U3DLmmeHDpjSbYZDkeoHOm7Fnxxjm7zwlg5TRi9hdrWnVHvsxucKZW3T1C3j m4FJnjhX19aaeVJwM3cuB1ircDHtvc2Su4Kz2p2C7M0BkZvp9PhXYNnn6RutBHP2C/wF W9k4MvLYFBrNyMxVBTfOeCpeiY79Sp4FSX2xypWVSTJw+RHADbuKNmKti5zJT6V+6qV8 7XODIgtDWwAKkdjxlM+MDTh5T2qLwGbDPeucWN/IzM9NrLaLDzh0ntjg352uanQfBSzG DF3yEE7wRysIDhxie283tttworKi7887tdp24ZBkebHut4FXMJBuGLTe7P0C/BtSelgc wJXA== X-Gm-Message-State: AOJu0Yyqo52NE4tBqAoONHP0usJD6jl03XiCSp5VibDqzT6BJpm2rqgP nGSQjxQIjUNmfQ87e6NdCAZDHcBZD4Q5QDA9X1+KM10s5+k= X-Google-Smtp-Source: AGHT+IFaDhAAh5ifHE4nFN9hpXUEZBg5fk3dU9x0fVGqYmGZghTkmZW4Fyfo7AZzPrt+SdiLys0JjA== X-Received: by 2002:a05:600c:154c:b0:40e:6279:9690 with SMTP id f12-20020a05600c154c00b0040e62799690mr4092640wmg.119.1705417950539; Tue, 16 Jan 2024 07:12:30 -0800 (PST) From: Peter Maydell To: qemu-devel@nongnu.org Subject: [PULL 03/21] docs/system/arm/virt.rst: Improve 'highmem' option docs Date: Tue, 16 Jan 2024 15:12:10 +0000 Message-Id: <20240116151228.2430754-4-peter.maydell@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240116151228.2430754-1-peter.maydell@linaro.org> References: <20240116151228.2430754-1-peter.maydell@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=2a00:1450:4864:20::330; envelope-from=peter.maydell@linaro.org; helo=mail-wm1-x330.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @linaro.org) X-ZM-MESSAGEID: 1705418089187100003 Improve the 'highmem' option docs to note that by default we assume that a 32-bit kernel on an LPAE-capable CPU has LPAE enabled, and what the consequences are. Signed-off-by: Peter Maydell Reviewed-by: Alex Benn=C3=A9e Reviewed-by: Eric Auger Message-id: 20240109170834.1387457-1-peter.maydell@linaro.org --- docs/system/arm/virt.rst | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/docs/system/arm/virt.rst b/docs/system/arm/virt.rst index 7c4c80180c6..c245c52b7ac 100644 --- a/docs/system/arm/virt.rst +++ b/docs/system/arm/virt.rst @@ -96,7 +96,13 @@ mte highmem Set ``on``/``off`` to enable/disable placing devices and RAM in physical address space above 32 bits. The default is ``on`` for machine types - later than ``virt-2.12``. + later than ``virt-2.12`` when the CPU supports an address space + bigger than 32 bits (i.e. 64-bit CPUs, and 32-bit CPUs with the + Large Physical Address Extension (LPAE) feature). If you want to + boot a 32-bit kernel which does not have ``CONFIG_LPAE`` enabled on + a CPU type which implements LPAE, you will need to manually set + this to ``off``; otherwise some devices, such as the PCI controller, + will not be accessible. =20 compact-highmem Set ``on``/``off`` to enable/disable the compact layout for high memory = regions. --=20 2.34.1