linux-kernel - [PATCH v2 8/9] KVM: arm64: Allow control of dpISA extensions in ID_AA64ISAR3

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20241030-arm64-2024-dpisa-v2-8-b6601a15d2a5@kernel.org>
Date: Wed, 30 Oct 2024 15:34:53 +0000
From: Mark Brown <broonie@...nel.org>
To: Catalin Marinas <catalin.marinas@....com>, 
 Will Deacon <will@...nel.org>, Jonathan Corbet <corbet@....net>, 
 Marc Zyngier <maz@...nel.org>, Oliver Upton <oliver.upton@...ux.dev>, 
 Joey Gouly <joey.gouly@....com>, Suzuki K Poulose <suzuki.poulose@....com>, 
 Shuah Khan <shuah@...nel.org>
Cc: linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org, 
 linux-doc@...r.kernel.org, kvmarm@...ts.linux.dev, 
 linux-kselftest@...r.kernel.org, Mark Brown <broonie@...nel.org>
Subject: [PATCH v2 8/9] KVM: arm64: Allow control of dpISA extensions in
 ID_AA64ISAR3_EL1

ID_AA64ISAR3_EL1 is currently marked as unallocated in KVM but does have a
number of bitfields defined in it. Expose FPRCVT and FAMINMAX, two simple
instruction only extensions to guests.

Signed-off-by: Mark Brown <broonie@...nel.org>
---
 arch/arm64/kvm/sys_regs.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index dad88e31f9537fe02e28b117d6a740f15572e0ba..926b6a1b2d2389e95721ce577740a2fb740e4f6b 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1546,6 +1546,9 @@ static u64 __kvm_read_sanitised_id_reg(const struct kvm_vcpu *vcpu,
 		if (!cpus_have_final_cap(ARM64_HAS_WFXT))
 			val &= ~ARM64_FEATURE_MASK(ID_AA64ISAR2_EL1_WFxT);
 		break;
+	case SYS_ID_AA64ISAR3_EL1:
+		val &= ID_AA64ISAR3_EL1_FPRCVT | ID_AA64ISAR3_EL1_FAMINMAX;
+		break;
 	case SYS_ID_AA64MMFR2_EL1:
 		val &= ~ID_AA64MMFR2_EL1_CCIDX_MASK;
 		break;
@@ -2409,7 +2412,8 @@ static const struct sys_reg_desc sys_reg_descs[] = {
 	ID_WRITABLE(ID_AA64ISAR2_EL1, ~(ID_AA64ISAR2_EL1_RES0 |
 					ID_AA64ISAR2_EL1_APA3 |
 					ID_AA64ISAR2_EL1_GPA3)),
-	ID_UNALLOCATED(6,3),
+	ID_WRITABLE(ID_AA64ISAR3_EL1, (ID_AA64ISAR3_EL1_FPRCVT |
+				       ID_AA64ISAR3_EL1_FAMINMAX)),
 	ID_UNALLOCATED(6,4),
 	ID_UNALLOCATED(6,5),
 	ID_UNALLOCATED(6,6),

-- 
2.39.2