| From 748cb5125b381330563b5339a4573827b015b0e9 Mon Sep 17 00:00:00 2001 |
| From: Andre Przywara <andre.przywara@arm.com> |
| Date: Fri, 17 May 2019 17:39:27 +0100 |
| Subject: [PATCH] arm64: kpti: Whitelist early Arm Neoverse N1 revisions |
| |
| Early revisions (r1p0) of the Neoverse N1 core did not feature the |
| CSV3 field in ID_AA64PFR0_EL1 to advertise they are not affected by |
| the Spectre variant 3 (aka Meltdown) vulnerability. |
| |
| Add this particular revision to the whitelist to avoid enabling KPTI. |
| |
| Signed-off-by: Andre Przywara <andre.przywara@arm.com> |
| |
| Upstream-Status: Inappropriate |
| Signed-off-by: Andre Przywara <andre.przywara@arm.com> |
| Signed-off-by: Vishnu Banavath <vishnu.banavath@arm.com> |
| Signed-off-by: Adam Johnston <adam.johnston@arm.com> |
| --- |
| arch/arm64/kernel/cpufeature.c | 1 + |
| 1 file changed, 1 insertion(+) |
| |
| diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c |
| index f34c9f8b9ee0..a778cf472d64 100644 |
| --- a/arch/arm64/kernel/cpufeature.c |
| +++ b/arch/arm64/kernel/cpufeature.c |
| @@ -1589,6 +1589,7 @@ static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry, |
| MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_2XX_SILVER), |
| MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER), |
| MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER), |
| + MIDR_REV(MIDR_NEOVERSE_N1, 1, 0), /* missing CSV3 */ |
| { /* sentinel */ } |
| }; |
| char const *str = "kpti command line option"; |