From patchwork Thu Aug 4 17:50:07 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julien Grall X-Patchwork-Id: 9264033 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 0B7676048B for ; Thu, 4 Aug 2016 17:53:08 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 041252841D for ; Thu, 4 Aug 2016 17:53:08 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id ECF6C28424; Thu, 4 Aug 2016 17:53:07 +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, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 7D6632841D for ; Thu, 4 Aug 2016 17:53:07 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1bVMmk-0004dx-8x; Thu, 04 Aug 2016 17:50:22 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1bVMmj-0004c5-EO for xen-devel@lists.xen.org; Thu, 04 Aug 2016 17:50:21 +0000 Received: from [85.158.137.68] by server-11.bemta-3.messagelabs.com id 43/C8-11394-C5083A75; Thu, 04 Aug 2016 17:50:20 +0000 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFrrGLMWRWlGSWpSXmKPExsVysyfVTTe6YXG 4we35phZLPi5mcWD0OLr7N1MAYxRrZl5SfkUCa0bL4Q2MBR0aFZN/LmNqYLwm38XIxSEksIlR YtekDYwQzmlGiYtPNrN2MXJysAloStz5/IkJxBYRkJa49vkyI4jNLOAg8ebjPZYuRg4OYYEAi feb9EDCLAKqEutbv4GV8Aq4SBy9cxFsjISAnMTJY5PBbE4BV4lJp34wg9hCQDXr1l1mmcDIvY CRYRWjRnFqUVlqka6hgV5SUWZ6RkluYmYOkGesl5taXJyYnpqTmFSsl5yfu4kR6N96BgbGHYz bupwPMUpyMCmJ8r6qXhwuxJeUn1KZkVicEV9UmpNafIhRhoNDSYL3SR1QTrAoNT21Ii0zBxho MGkJDh4lEV65eqA0b3FBYm5xZjpE6hSjopQ472uQPgGQREZpHlwbLLgvMcpKCfMyMjAwCPEUp BblZpagyr9iFOdgVBLmPQQyhSczrwRu+iugxUxAi08YLABZXJKIkJJqYNzU+eLIhLadwrf3HH dxeKI+K1nG49i2ByVp57uOHzt63O/h//17t29oex0Yfqj0RHP2Z3OhlTMm8lRt8v51KD+1quT Eg5uK5m//OglOa+EQes604HBiqYit3wtHWwV1Z5tw4Uzxj8d5LSfKJKp7JjW+OBWtqKB74Nkd 7dKPDZHGT6YuWRMv76PEUpyRaKjFXFScCADvfs5saQIAAA== X-Env-Sender: julien.grall@arm.com X-Msg-Ref: server-2.tower-31.messagelabs.com!1470333017!54024273!2 X-Originating-IP: [217.140.101.70] X-SpamReason: No, hits=0.0 required=7.0 tests= X-StarScan-Received: X-StarScan-Version: 8.77; banners=-,-,- X-VirusChecked: Checked Received: (qmail 37568 invoked from network); 4 Aug 2016 17:50:19 -0000 Received: from foss.arm.com (HELO foss.arm.com) (217.140.101.70) by server-2.tower-31.messagelabs.com with SMTP; 4 Aug 2016 17:50:19 -0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 4B9C641D; Thu, 4 Aug 2016 10:51:42 -0700 (PDT) Received: from e108454-lin.cambridge.arm.com (e108454-lin.cambridge.arm.com [10.1.218.32]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A931E3F387; Thu, 4 Aug 2016 10:50:18 -0700 (PDT) From: Julien Grall To: xen-devel@lists.xen.org Date: Thu, 4 Aug 2016 18:50:07 +0100 Message-Id: <1470333007-25178-7-git-send-email-julien.grall@arm.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1470333007-25178-1-git-send-email-julien.grall@arm.com> References: <1470333007-25178-1-git-send-email-julien.grall@arm.com> Cc: Julien Grall , sstabellini@kernel.org Subject: [Xen-devel] [PATCH v3 6/6] xen/arm: arm64: Add Cortex-A57 erratum 834220 workaround X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" X-Virus-Scanned: ClamAV using ClamSMTP The ARM erratum applies to certain revisions of Cortex-A57. The processor may report a Stage 2 translation fault as the result of Stage 1 fault for load crossing a page boundary when there is a permission fault or device memory fault at stage 1 and a translation fault at Stage 2. So Xen needs to check that Stage 1 translation does not generate a fault before handling the Stage 2 fault. If it is a Stage 1 translation fault, return to the guest to let the processor injecting the correct fault. Signed-off-by: Julien Grall Reviewed-by: Stefano Stabellini --- Changes in v2: - Add Stefano's reviewed-by --- docs/misc/arm/silicon-errata.txt | 1 + xen/arch/arm/Kconfig | 21 +++++++++++++++++++++ xen/arch/arm/cpuerrata.c | 9 +++++++++ xen/arch/arm/traps.c | 5 +++-- xen/include/asm-arm/cpuerrata.h | 1 + xen/include/asm-arm/cpufeature.h | 3 ++- 6 files changed, 37 insertions(+), 3 deletions(-) diff --git a/docs/misc/arm/silicon-errata.txt b/docs/misc/arm/silicon-errata.txt index 220f724..c9854c3 100644 --- a/docs/misc/arm/silicon-errata.txt +++ b/docs/misc/arm/silicon-errata.txt @@ -47,3 +47,4 @@ stable hypervisors. | ARM | Cortex-A53 | #819472 | ARM64_ERRATUM_819472 | | ARM | Cortex-A57 | #852523 | N/A | | ARM | Cortex-A57 | #832075 | ARM64_ERRATUM_832075 | +| ARM | Cortex-A57 | #834220 | ARM64_ERRATUM_834220 | diff --git a/xen/arch/arm/Kconfig b/xen/arch/arm/Kconfig index e26c4c8..871c243 100644 --- a/xen/arch/arm/Kconfig +++ b/xen/arch/arm/Kconfig @@ -142,6 +142,27 @@ config ARM64_ERRATUM_832075 If unsure, say Y. +config ARM64_ERRATUM_834220 + bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault" + default y + depends on ARM_64 + help + This option adds an alternative code sequence to work around ARM + erratum 834220 on Cortex-A57 parts up to r1p2. + + Affected Cortex-A57 parts might report a Stage 2 translation + fault as the result of a Stage 1 fault for load crossing a + page boundary when there is a permission or device memory + alignment fault at Stage 1 and a translation fault at Stage 2. + + The workaround is to verify that the Stage 1 translation + doesn't generate a fault before handling the Stage 2 fault. + Please note that this does not necessarily enable the workaround, + as it depends on the alternative framework, which will only patch + the kernel if an affected CPU is detected. + + If unsure, say Y. + endmenu source "common/Kconfig" diff --git a/xen/arch/arm/cpuerrata.c b/xen/arch/arm/cpuerrata.c index 748e02e..a3e8dda 100644 --- a/xen/arch/arm/cpuerrata.c +++ b/xen/arch/arm/cpuerrata.c @@ -49,6 +49,15 @@ static const struct arm_cpu_capabilities arm_errata[] = { (1 << MIDR_VARIANT_SHIFT) | 2), }, #endif +#ifdef CONFIG_ARM64_ERRATUM_834220 + { + /* Cortex-A57 r0p0 - r1p2 */ + .desc = "ARM erratum 834220", + .capability = ARM64_WORKAROUND_834220, + MIDR_RANGE(MIDR_CORTEX_A57, 0x00, + (1 << MIDR_VARIANT_SHIFT) | 2), + }, +#endif {}, }; diff --git a/xen/arch/arm/traps.c b/xen/arch/arm/traps.c index 0ec0361..683bcb2 100644 --- a/xen/arch/arm/traps.c +++ b/xen/arch/arm/traps.c @@ -2388,12 +2388,13 @@ static inline bool hpfar_is_valid(bool s1ptw, uint8_t fsc) * HPFAR is valid if one of the following cases are true: * 1. the stage 2 fault happen during a stage 1 page table walk * (the bit ESR_EL2.S1PTW is set) - * 2. the fault was due to a translation fault + * 2. the fault was due to a translation fault and the processor + * does not carry erratum #8342220 * * Note that technically HPFAR is valid for other cases, but they * are currently not supported by Xen. */ - return s1ptw || (fsc == FSC_FLT_TRANS); + return s1ptw || (fsc == FSC_FLT_TRANS && !check_workaround_834220()); } static void do_trap_instr_abort_guest(struct cpu_user_regs *regs, diff --git a/xen/include/asm-arm/cpuerrata.h b/xen/include/asm-arm/cpuerrata.h index 5880e77..5e35b4f 100644 --- a/xen/include/asm-arm/cpuerrata.h +++ b/xen/include/asm-arm/cpuerrata.h @@ -41,6 +41,7 @@ static inline bool_t check_workaround_##erratum(void) \ #endif CHECK_WORKAROUND_HELPER(766422, ARM32_WORKAROUND_766422, CONFIG_ARM_32) +CHECK_WORKAROUND_HELPER(834220, ARM64_WORKAROUND_834220, CONFIG_ARM_64) #undef CHECK_WORKAROUND_HELPER diff --git a/xen/include/asm-arm/cpufeature.h b/xen/include/asm-arm/cpufeature.h index ac6eaf0..66e930f 100644 --- a/xen/include/asm-arm/cpufeature.h +++ b/xen/include/asm-arm/cpufeature.h @@ -38,8 +38,9 @@ #define ARM64_WORKAROUND_CLEAN_CACHE 0 #define ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE 1 #define ARM32_WORKAROUND_766422 2 +#define ARM64_WORKAROUND_834220 3 -#define ARM_NCAPS 3 +#define ARM_NCAPS 4 #ifndef __ASSEMBLY__