From: Marc Zyngier <maz@kernel.org>
To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev
Cc: Will Deacon <will@kernel.org>,
Catalin Marinas <catalin.marinas@arm.com>,
Mark Rutland <mark.rutland@arm.com>,
Joey Gouly <joey.gouly@arm.com>,
Suzuki K Poulose <suzuki.poulose@arm.com>,
Oliver Upton <oupton@kernel.org>,
Zenghui Yu <yuzenghui@huawei.com>
Subject: [PATCH 3/3] arm64: Unconditionally enable EPAN support
Date: Wed, 7 Jan 2026 18:07:01 +0000 [thread overview]
Message-ID: <20260107180701.2858276-4-maz@kernel.org> (raw)
In-Reply-To: <20260107180701.2858276-1-maz@kernel.org>
While FEAT_PAN3 is pretty recent, having it permanently enabled costs
exactly nothing, and does help with exec-only mappings on these fancy
ARMv9.2 machines that are rumoured to exist.
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/Kconfig | 13 -------------
arch/arm64/configs/hardening.config | 3 ---
arch/arm64/include/asm/cpucaps.h | 2 --
arch/arm64/kernel/cpufeature.c | 2 --
4 files changed, 20 deletions(-)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index fcfb62ec4bae8..c31079f4b611a 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -2120,19 +2120,6 @@ config ARM64_MTE
endmenu # "ARMv8.5 architectural features"
-menu "ARMv8.7 architectural features"
-
-config ARM64_EPAN
- bool "Enable support for Enhanced Privileged Access Never (EPAN)"
- default y
- help
- Enhanced Privileged Access Never (EPAN) allows Privileged
- Access Never to be used with Execute-only mappings.
-
- The feature is detected at runtime, and will remain disabled
- if the cpu does not implement the feature.
-endmenu # "ARMv8.7 architectural features"
-
config AS_HAS_MOPS
def_bool $(as-instr,.arch_extension mops)
diff --git a/arch/arm64/configs/hardening.config b/arch/arm64/configs/hardening.config
index 24179722927e1..e59034e7af256 100644
--- a/arch/arm64/configs/hardening.config
+++ b/arch/arm64/configs/hardening.config
@@ -18,6 +18,3 @@ CONFIG_ARM64_BTI_KERNEL=y
CONFIG_ARM64_MTE=y
CONFIG_KASAN_HW_TAGS=y
CONFIG_ARM64_E0PD=y
-
-# Available in ARMv8.7 and later.
-CONFIG_ARM64_EPAN=y
diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h
index 177c691914f87..13c0fa54ea19f 100644
--- a/arch/arm64/include/asm/cpucaps.h
+++ b/arch/arm64/include/asm/cpucaps.h
@@ -19,8 +19,6 @@ cpucap_is_possible(const unsigned int cap)
"cap must be < ARM64_NCAPS");
switch (cap) {
- case ARM64_HAS_EPAN:
- return IS_ENABLED(CONFIG_ARM64_EPAN);
case ARM64_SVE:
return IS_ENABLED(CONFIG_ARM64_SVE);
case ARM64_SME:
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 716440d147a2d..30eea68178c87 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -2547,7 +2547,6 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
.cpu_enable = cpu_enable_pan,
ARM64_CPUID_FIELDS(ID_AA64MMFR1_EL1, PAN, IMP)
},
-#ifdef CONFIG_ARM64_EPAN
{
.desc = "Enhanced Privileged Access Never",
.capability = ARM64_HAS_EPAN,
@@ -2555,7 +2554,6 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
.matches = has_cpuid_feature,
ARM64_CPUID_FIELDS(ID_AA64MMFR1_EL1, PAN, PAN3)
},
-#endif /* CONFIG_ARM64_EPAN */
{
.desc = "LSE atomic instructions",
.capability = ARM64_HAS_LSE_ATOMICS,
--
2.47.3
next prev parent reply other threads:[~2026-01-07 18:07 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-07 18:06 [PATCH 0/3] arm64: Unconditionally compile LSE/PAN/EPAN support Marc Zyngier
2026-01-07 18:06 ` [PATCH 1/3] arm64: Unconditionally enable LSE support Marc Zyngier
2026-01-07 18:07 ` [PATCH 2/3] arm64: Unconditionally enable PAN support Marc Zyngier
2026-01-22 11:21 ` Marc Zyngier
2026-01-22 17:02 ` Will Deacon
2026-01-07 18:07 ` Marc Zyngier [this message]
2026-01-22 10:15 ` [PATCH 3/3] arm64: Unconditionally enable EPAN support Will Deacon
2026-01-22 11:06 ` Marc Zyngier
2026-01-22 16:59 ` [PATCH 0/3] arm64: Unconditionally compile LSE/PAN/EPAN support Will Deacon
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