From patchwork Mon Feb 5 20:11:30 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Timur Tabi X-Patchwork-Id: 10201787 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 703976056A for ; Mon, 5 Feb 2018 20:12:16 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5ED7F2837E for ; Mon, 5 Feb 2018 20:12:16 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 537C6285C9; Mon, 5 Feb 2018 20:12:16 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 97A2C2837E for ; Mon, 5 Feb 2018 20:12:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=IbqCQm98Rmymu+lFrRRlyCFql2ZtIPJ32bia01CzwQU=; b=gGoevXtBzK83TqDpW5swo8AyoB lGG6TQZFlcr3kWekCSvHI3z4mHcgI7dJ3sm8np8HfgzotELAgynZWePatGZQrGkonx0sqLDoIv7YH feLdjkfm0kP82CtXlGiQ77VpUpAmsVMV9KZ3jOEjutXkJmM2BTXXycaqREtLV1FaqiHeonJxNRIf1 e0EALjF9Q7rKl89C4gOisdeDsKpWnwrV4NQSS+vNkLkzcb5dluqpidPbN6egs2nZIWLc6O5ggiVrI KlHnEjkdBDmK/t9u3pXbCeJFUmH4ymxDuPfDYIgmd8c+xOwCyrw9f/VCinXmiUtBe7RS8Nb4mhHee EuChsaNQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.89 #1 (Red Hat Linux)) id 1ein7e-0007BT-1E; Mon, 05 Feb 2018 20:12:14 +0000 Received: from smtp.codeaurora.org ([198.145.29.96]) by bombadil.infradead.org with esmtps (Exim 4.89 #1 (Red Hat Linux)) id 1ein7B-0006hE-TE for linux-arm-kernel@lists.infradead.org; Mon, 05 Feb 2018 20:11:48 +0000 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 8A9756090E; Mon, 5 Feb 2018 20:11:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1517861496; bh=LbxDNshhJfAdBUucjAtehIiV2ZoZXtRZ43gUmMwnNPk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=g1HFZivU7NEPqZ7ISnj4bzEsnb0tefe9KWF9PESMAgt9cElcXp7aIqgcuKKqTf8nm 2Lhg2R5NkGyZZTxviVIgouARQiMvxuB+n0cI9cQ8QLgakO6/yKtIHe/ZZeTg6VKQvj 9kCKwV7+LgZI6utrvrv1DpSHGXch91uUWnryX+i0= Received: from timur-ubuntu.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: timur@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 7918660767; Mon, 5 Feb 2018 20:11:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1517861496; bh=LbxDNshhJfAdBUucjAtehIiV2ZoZXtRZ43gUmMwnNPk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=g1HFZivU7NEPqZ7ISnj4bzEsnb0tefe9KWF9PESMAgt9cElcXp7aIqgcuKKqTf8nm 2Lhg2R5NkGyZZTxviVIgouARQiMvxuB+n0cI9cQ8QLgakO6/yKtIHe/ZZeTg6VKQvj 9kCKwV7+LgZI6utrvrv1DpSHGXch91uUWnryX+i0= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 7918660767 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=timur@codeaurora.org From: Timur Tabi To: stable@vger.kernel.org, Shanker Donthineni , linux-arm-kernel@lists.infradead.org Subject: [PATCH 2/2] [for 4.14] arm64: Add software workaround for Falkor erratum 1041 Date: Mon, 5 Feb 2018 14:11:30 -0600 Message-Id: <1517861490-19395-3-git-send-email-timur@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1517861490-19395-1-git-send-email-timur@codeaurora.org> References: <1517861490-19395-1-git-send-email-timur@codeaurora.org> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: timur@codeaurora.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Shanker Donthineni commit 932b50c7c1c6 upstream The ARM architecture defines the memory locations that are permitted to be accessed as the result of a speculative instruction fetch from an exception level for which all stages of translation are disabled. Specifically, the core is permitted to speculatively fetch from the 4KB region containing the current program counter 4K and next 4K. When translation is changed from enabled to disabled for the running exception level (SCTLR_ELn[M] changed from a value of 1 to 0), the Falkor core may errantly speculatively access memory locations outside of the 4KB region permitted by the architecture. The errant memory access may lead to one of the following unexpected behaviors. 1) A System Error Interrupt (SEI) being raised by the Falkor core due to the errant memory access attempting to access a region of memory that is protected by a slave-side memory protection unit. 2) Unpredictable device behavior due to a speculative read from device memory. This behavior may only occur if the instruction cache is disabled prior to or coincident with translation being changed from enabled to disabled. The conditions leading to this erratum will not occur when either of the following occur: 1) A higher exception level disables translation of a lower exception level (e.g. EL2 changing SCTLR_EL1[M] from a value of 1 to 0). 2) An exception level disabling its stage-1 translation if its stage-2 translation is enabled (e.g. EL1 changing SCTLR_EL1[M] from a value of 1 to 0 when HCR_EL2[VM] has a value of 1). To avoid the errant behavior, software must execute an ISB immediately prior to executing the MSR that will change SCTLR_ELn[M] from 1 to 0. Signed-off-by: Shanker Donthineni Signed-off-by: Will Deacon --- A minor conflict in arch/arm64/Kconfig was resolved when back-porting this commit from 4.15. Documentation/arm64/silicon-errata.txt | 1 + arch/arm64/Kconfig | 10 ++++++++++ arch/arm64/include/asm/assembler.h | 10 ++++++++++ arch/arm64/kernel/cpu-reset.S | 1 + arch/arm64/kernel/efi-entry.S | 2 ++ arch/arm64/kernel/head.S | 1 + arch/arm64/kernel/relocate_kernel.S | 1 + arch/arm64/kvm/hyp-init.S | 1 + 8 files changed, 27 insertions(+) diff --git a/Documentation/arm64/silicon-errata.txt b/Documentation/arm64/silicon-errata.txt index 66e8ce14d23d..704770c0edf2 100644 --- a/Documentation/arm64/silicon-errata.txt +++ b/Documentation/arm64/silicon-errata.txt @@ -74,3 +74,4 @@ stable kernels. | Qualcomm Tech. | Falkor v1 | E1003 | QCOM_FALKOR_ERRATUM_1003 | | Qualcomm Tech. | Falkor v1 | E1009 | QCOM_FALKOR_ERRATUM_1009 | | Qualcomm Tech. | QDF2400 ITS | E0065 | QCOM_QDF2400_ERRATUM_0065 | +| Qualcomm Tech. | Falkor v{1,2} | E1041 | QCOM_FALKOR_ERRATUM_1041 | diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 0df64a6a56d4..8f73eaccf50a 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -539,6 +539,16 @@ config QCOM_QDF2400_ERRATUM_0065 If unsure, say Y. +config QCOM_FALKOR_ERRATUM_E1041 + bool "Falkor E1041: Speculative instruction fetches might cause errant memory access" + default y + help + Falkor CPU may speculatively fetch instructions from an improper + memory location when MMU translation is changed from SCTLR_ELn[M]=1 + to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem. + + If unsure, say Y. + endmenu diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index d58a6253c6ab..7896728f3b22 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -499,4 +499,14 @@ #endif .endm +/** + * Errata workaround prior to disable MMU. Insert an ISB immediately prior + * to executing the MSR that will change SCTLR_ELn[M] from a value of 1 to 0. + */ + .macro pre_disable_mmu_workaround +#ifdef CONFIG_QCOM_FALKOR_ERRATUM_E1041 + isb +#endif + .endm + #endif /* __ASM_ASSEMBLER_H */ diff --git a/arch/arm64/kernel/cpu-reset.S b/arch/arm64/kernel/cpu-reset.S index 65f42d257414..2a752cb2a0f3 100644 --- a/arch/arm64/kernel/cpu-reset.S +++ b/arch/arm64/kernel/cpu-reset.S @@ -37,6 +37,7 @@ ENTRY(__cpu_soft_restart) mrs x12, sctlr_el1 ldr x13, =SCTLR_ELx_FLAGS bic x12, x12, x13 + pre_disable_mmu_workaround msr sctlr_el1, x12 isb diff --git a/arch/arm64/kernel/efi-entry.S b/arch/arm64/kernel/efi-entry.S index 4e6ad355bd05..6b9736c3fb56 100644 --- a/arch/arm64/kernel/efi-entry.S +++ b/arch/arm64/kernel/efi-entry.S @@ -96,6 +96,7 @@ ENTRY(entry) mrs x0, sctlr_el2 bic x0, x0, #1 << 0 // clear SCTLR.M bic x0, x0, #1 << 2 // clear SCTLR.C + pre_disable_mmu_workaround msr sctlr_el2, x0 isb b 2f @@ -103,6 +104,7 @@ ENTRY(entry) mrs x0, sctlr_el1 bic x0, x0, #1 << 0 // clear SCTLR.M bic x0, x0, #1 << 2 // clear SCTLR.C + pre_disable_mmu_workaround msr sctlr_el1, x0 isb 2: diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 0b243ecaf7ac..6657ae4f3c7a 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -732,6 +732,7 @@ __primary_switch: * to take into account by discarding the current kernel mapping and * creating a new one. */ + pre_disable_mmu_workaround msr sctlr_el1, x20 // disable the MMU isb bl __create_page_tables // recreate kernel mapping diff --git a/arch/arm64/kernel/relocate_kernel.S b/arch/arm64/kernel/relocate_kernel.S index ce704a4aeadd..f407e422a720 100644 --- a/arch/arm64/kernel/relocate_kernel.S +++ b/arch/arm64/kernel/relocate_kernel.S @@ -45,6 +45,7 @@ ENTRY(arm64_relocate_new_kernel) mrs x0, sctlr_el2 ldr x1, =SCTLR_ELx_FLAGS bic x0, x0, x1 + pre_disable_mmu_workaround msr sctlr_el2, x0 isb 1: diff --git a/arch/arm64/kvm/hyp-init.S b/arch/arm64/kvm/hyp-init.S index 3f9615582377..870828c364c5 100644 --- a/arch/arm64/kvm/hyp-init.S +++ b/arch/arm64/kvm/hyp-init.S @@ -151,6 +151,7 @@ reset: mrs x5, sctlr_el2 ldr x6, =SCTLR_ELx_FLAGS bic x5, x5, x6 // Clear SCTL_M and etc + pre_disable_mmu_workaround msr sctlr_el2, x5 isb