From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6083132548C for ; Wed, 7 Jan 2026 18:07:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767809229; cv=none; b=NJ8VQ2pR1QtavsdcoT1+waEWIyAoXP5wpV+tNycNEG8XptxazaX73eDwoBN6wgb7TycQPMQjoZkvn5urAdJejfnqVM2s6tzyBNDhiRideRhjwiTHakJvlJYSdyFo4TqA686x6/H97n+W0lWjnqwh9xfcaRZRBoiW/GTF2rM8CoU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767809229; c=relaxed/simple; bh=xXE/PlTwR8mL0+jghSbaljIqMREGIinKz771yCV9QtA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=aDqtlHQknE6FiexD7h04WEvy70rVY6EDtpIjYLIz1PlfTUqsiEkXoikszmV7N7BlsVQqbTiiEKMQngfBSTSpJHvPNCxaXGzAyE7U8lZ9tTfzVhltqDIqlc/Ngij21WbcZ+E/Wq5cGF97VsAj5H/PI3c4Qun1Lrk9Ju1DEs025KQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=L1vdAJjt; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="L1vdAJjt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D2D0DC4CEF7; Wed, 7 Jan 2026 18:07:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1767809228; bh=xXE/PlTwR8mL0+jghSbaljIqMREGIinKz771yCV9QtA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=L1vdAJjtamO6TJmlh2ImsjLWtgjJX7WbIZZ+PoGkhVgyyEfrJlRUYUvAj94g1AyGr CTKabkogo2XFQ2z1rLmBY3FZQdsPFYFf58M3DX8yBLWl757sQd9DXDvzWHkDU0I65L OCtGtKkHxOVFz2UndTaP6if6QW4oNB7SCc5cOUALrwQFxLDf3bBSSzG00nHyJBUruK LPisK2J/uMaFH7LgPDqTK6yNrc1fcJqzhSYndhrsID4BEpNZNCmL6+fqXG/6Su4Erp XU5j4abvo3sowRKwWVrMdswU4+M4vBzL2bwNVXa+awdzEs14kp/ju3q9M8as06UydA 6iz47Rhbk7a0Q== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1vdXw2-00000000A9B-28Wh; Wed, 07 Jan 2026 18:07:06 +0000 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev Cc: Will Deacon , Catalin Marinas , Mark Rutland , Joey Gouly , Suzuki K Poulose , Oliver Upton , Zenghui Yu Subject: [PATCH 3/3] arm64: Unconditionally enable EPAN support Date: Wed, 7 Jan 2026 18:07:01 +0000 Message-ID: <20260107180701.2858276-4-maz@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260107180701.2858276-1-maz@kernel.org> References: <20260107180701.2858276-1-maz@kernel.org> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, will@kernel.org, catalin.marinas@arm.com, mark.rutland@arm.com, joey.gouly@arm.com, suzuki.poulose@arm.com, oupton@kernel.org, yuzenghui@huawei.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false 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 --- 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