Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, James Morse <james.morse@arm.com>,
        Will Deacon <will@kernel.org>, Lucas Wei <lucaswei@google.com>
Subject: [PATCH 5.19 06/72] arm64: errata: Add Cortex-A510 to the repeat tlbi list
Date:   Fri,  2 Sep 2022 14:18:42 +0200
Message-Id: <20220902121404.999570603@linuxfoundation.org>
In-Reply-To: <20220902121404.772492078@linuxfoundation.org>
References: <20220902121404.772492078@linuxfoundation.org>
User-Agent: quilt/0.67
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: James Morse <james.morse@arm.com>

commit 39fdb65f52e9a53d32a6ba719f96669fd300ae78 upstream.

Cortex-A510 is affected by an erratum where in rare circumstances the
CPUs may not handle a race between a break-before-make sequence on one
CPU, and another CPU accessing the same page. This could allow a store
to a page that has been unmapped.

Work around this by adding the affected CPUs to the list that needs
TLB sequences to be done twice.

Signed-off-by: James Morse <james.morse@arm.com>
Link: https://lore.kernel.org/r/20220704155732.21216-1-james.morse@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Cc: Lucas Wei <lucaswei@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 Documentation/arm64/silicon-errata.rst |    2 ++
 arch/arm64/Kconfig                     |   17 +++++++++++++++++
 arch/arm64/kernel/cpu_errata.c         |    8 +++++++-
 3 files changed, 26 insertions(+), 1 deletion(-)

--- a/Documentation/arm64/silicon-errata.rst
+++ b/Documentation/arm64/silicon-errata.rst
@@ -106,6 +106,8 @@ stable kernels.
 +----------------+-----------------+-----------------+-----------------------------+
 | ARM            | Cortex-A510     | #2077057        | ARM64_ERRATUM_2077057       |
 +----------------+-----------------+-----------------+-----------------------------+
+| ARM            | Cortex-A510     | #2441009        | ARM64_ERRATUM_2441009       |
++----------------+-----------------+-----------------+-----------------------------+
 | ARM            | Cortex-A710     | #2119858        | ARM64_ERRATUM_2119858       |
 +----------------+-----------------+-----------------+-----------------------------+
 | ARM            | Cortex-A710     | #2054223        | ARM64_ERRATUM_2054223       |
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -838,6 +838,23 @@ config ARM64_ERRATUM_2224489
 
 	  If unsure, say Y.
 
+config ARM64_ERRATUM_2441009
+	bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
+	default y
+	select ARM64_WORKAROUND_REPEAT_TLBI
+	help
+	  This option adds a workaround for ARM Cortex-A510 erratum #2441009.
+
+	  Under very rare circumstances, affected Cortex-A510 CPUs
+	  may not handle a race between a break-before-make sequence on one
+	  CPU, and another CPU accessing the same page. This could allow a
+	  store to a page that has been unmapped.
+
+	  Work around this by adding the affected CPUs to the list that needs
+	  TLB sequences to be done twice.
+
+	  If unsure, say Y.
+
 config ARM64_ERRATUM_2064142
 	bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled"
 	depends on CORESIGHT_TRBE
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -214,6 +214,12 @@ static const struct arm64_cpu_capabiliti
 		ERRATA_MIDR_RANGE(MIDR_QCOM_KRYO_4XX_GOLD, 0xc, 0xe, 0xf, 0xe),
 	},
 #endif
+#ifdef CONFIG_ARM64_ERRATUM_2441009
+	{
+		/* Cortex-A510 r0p0 -> r1p1. Fixed in r1p2 */
+		ERRATA_MIDR_RANGE(MIDR_CORTEX_A510, 0, 0, 1, 1),
+	},
+#endif
 	{},
 };
 #endif
@@ -490,7 +496,7 @@ const struct arm64_cpu_capabilities arm6
 #endif
 #ifdef CONFIG_ARM64_WORKAROUND_REPEAT_TLBI
 	{
-		.desc = "Qualcomm erratum 1009, or ARM erratum 1286807",
+		.desc = "Qualcomm erratum 1009, or ARM erratum 1286807, 2441009",
 		.capability = ARM64_WORKAROUND_REPEAT_TLBI,
 		.type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,
 		.matches = cpucap_multi_entry_cap_matches,