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=-20.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 23004C433B4 for ; Wed, 14 Apr 2021 06:22:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 03C2E611EE for ; Wed, 14 Apr 2021 06:22:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349216AbhDNGWn (ORCPT ); Wed, 14 Apr 2021 02:22:43 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:51056 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232405AbhDNGWi (ORCPT ); Wed, 14 Apr 2021 02:22:38 -0400 Date: Wed, 14 Apr 2021 06:22:14 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1618381335; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Sj8bKQs3EzaDo1n24IZ7KqWvkhErmm1PrSIWnyuBl1I=; b=asast63DGsjZ1sz8ZaEtepCNbMu9OG/HV8166DvS+9Ta28rHVooyJLFmBOMxG0yTfAAkAU RE2nQK0QCiMqJKX/zbo9oVRJi3PbMkUhJ2T9bfVAI5oEaY4Qiw/eD5JMN2J9/WR+x1htGj RVgrgetUVRKK27JCcKW0U6NWKoMx1QrRielCTKLp/RaxbbUwSONEu77AwLyxJWOrWulZfj FkdoATUhLJfVLfearKjuukuzS5eFkgt85zffaB7r+yBOkS0AeCmiqqxXD4k2Z9SHpfWs/y uSOrFP9sphVCW3QU8fI9f00vgy8pZeSc7pL7FR2Golzmp2CD85KkqxNuazmQ8w== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1618381335; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Sj8bKQs3EzaDo1n24IZ7KqWvkhErmm1PrSIWnyuBl1I=; b=5wIhF45LzyXhv//dLiJ6MzpzsG9ZAngO+VD3oiwt9IFzVmPskk+T3oROAKItX6PSPBrAmS PGrVX+1nAkdoxgCA== From: "tip-bot2 for Mike Rapoport" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/boot] x86/setup: Move trim_snb_memory() later in setup_arch() to fix boot hangs Cc: Randy Dunlap , Mike Rapoport , Borislav Petkov , Hugh Dickins , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: References: MIME-Version: 1.0 Message-ID: <161838133498.29796.12540775721070465830.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the x86/boot branch of tip: Commit-ID: c361e5d4d07d63768880e1994c7ed999b3a94cd9 Gitweb: https://git.kernel.org/tip/c361e5d4d07d63768880e1994c7ed999b3a94cd9 Author: Mike Rapoport AuthorDate: Tue, 13 Apr 2021 21:08:39 +03:00 Committer: Borislav Petkov CommitterDate: Wed, 14 Apr 2021 08:16:48 +02:00 x86/setup: Move trim_snb_memory() later in setup_arch() to fix boot hangs Commit a799c2bd29d1 ("x86/setup: Consolidate early memory reservations") moved reservation of the memory inaccessible by Sandy Bride integrated graphics very early, and, as a result, on systems with such devices the first 1M was reserved by trim_snb_memory() which prevented the allocation of the real mode trampoline and made the boot hang very early. Since the purpose of trim_snb_memory() is to prevent problematic pages ever reaching the graphics device, it is safe to reserve these pages after memblock allocations are possible. Move trim_snb_memory() later in boot so that it will be called after reserve_real_mode() and make comments describing trim_snb_memory() operation more elaborate. [ bp: Massage a bit. ] Fixes: a799c2bd29d1 ("x86/setup: Consolidate early memory reservations") Reported-by: Randy Dunlap Signed-off-by: Mike Rapoport Signed-off-by: Borislav Petkov Tested-by: Randy Dunlap Tested-by: Hugh Dickins Link: https://lkml.kernel.org/r/f67d3e03-af90-f790-baf4-8d412fe055af@infradead.org --- arch/x86/kernel/setup.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 776fc9b..e93283e 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -633,11 +633,16 @@ static void __init trim_snb_memory(void) printk(KERN_DEBUG "reserving inaccessible SNB gfx pages\n"); /* - * Reserve all memory below the 1 MB mark that has not - * already been reserved. + * SandyBridge integrated graphics devices have a bug that prevents + * them from accessing certain memory ranges, namely anything below + * 1M and in the pages listed in bad_pages[] above. + * + * To avoid these pages being ever accessed by SNB gfx devices + * reserve all memory below the 1 MB mark and bad_pages that have + * not already been reserved at boot time. */ memblock_reserve(0, 1<<20); - + for (i = 0; i < ARRAY_SIZE(bad_pages); i++) { if (memblock_reserve(bad_pages[i], PAGE_SIZE)) printk(KERN_WARNING "failed to reserve 0x%08lx\n", @@ -746,8 +751,6 @@ static void __init early_reserve_memory(void) reserve_ibft_region(); reserve_bios_regions(); - - trim_snb_memory(); } /* @@ -1081,6 +1084,13 @@ void __init setup_arch(char **cmdline_p) reserve_real_mode(); + /* + * Reserving memory causing GPU hangs on Sandy Bridge integrated + * graphics devices should be done after we allocated memory under + * 1M for the real mode trampoline. + */ + trim_snb_memory(); + init_mem_mapping(); idt_setup_early_pf();