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=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,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 2D37CC31E46 for ; Wed, 12 Jun 2019 05:02:59 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 A7A3320866 for ; Wed, 12 Jun 2019 05:02:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A7A3320866 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 45Nvrc3CwVzDqsx for ; Wed, 12 Jun 2019 15:02:56 +1000 (AEST) Received: from ozlabs.org (bilbo.ozlabs.org [203.11.71.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 45NvmH2Q2xzDqsv for ; Wed, 12 Jun 2019 14:59:11 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Received: by ozlabs.org (Postfix, from userid 1034) id 45NvmH0kL6z9sBr; Wed, 12 Jun 2019 14:59:10 +1000 (AEST) X-powerpc-patch-notification: thanks X-powerpc-patch-commit: c21f5a9ed85ca3e914ca11f421677ae9ae0d04b0 X-Patchwork-Hint: ignore In-Reply-To: <90d30adb0943a11ab127808c03229ba657478df4.1559566521.git.christophe.leroy@c-s.fr> To: Christophe Leroy , Benjamin Herrenschmidt , Paul Mackerras , Mathieu Malaterre From: Michael Ellerman Subject: Re: [PATCH] powerpc/32s: fix booting with CONFIG_PPC_EARLY_DEBUG_BOOTX Message-Id: <45NvmH0kL6z9sBr@ozlabs.org> Date: Wed, 12 Jun 2019 14:59:10 +1000 (AEST) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon, 2019-06-03 at 13:00:51 UTC, Christophe Leroy wrote: > When booting through OF, setup_disp_bat() does nothing because > disp_BAT are not set. By change, it used to work because BOOTX > buffer is mapped 1:1 at address 0x81000000 by the bootloader, and > btext_setup_display() sets virt addr same as phys addr. > > But since commit 215b823707ce ("powerpc/32s: set up an early static > hash table for KASAN."), a temporary page table overrides the > bootloader mapping. > > This 0x81000000 is also problematic with the newly implemented > Kernel Userspace Access Protection (KUAP) because it is within user > address space. > > This patch fixes those issues by properly setting disp_BAT through > a call to btext_prepare_BAT(), allowing setup_disp_bat() to > properly setup BAT3 for early bootx screen buffer access. > > Reported-by: Mathieu Malaterre > Fixes: 215b823707ce ("powerpc/32s: set up an early static hash table for KASAN.") > Signed-off-by: Christophe Leroy > Tested-by: Mathieu Malaterre Applied to powerpc fixes, thanks. https://git.kernel.org/powerpc/c/c21f5a9ed85ca3e914ca11f421677ae9 cheers