From: Marc Zyngier <maz@kernel.org>
To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org,
kvm@vger.kernel.org
Cc: Steffen Eiden <seiden@linux.ibm.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 07/28] KVM: arm64: Don't evaluate HCR_EL2.NV on ERET fast path
Date: Thu, 2 Jul 2026 17:02:27 +0100 [thread overview]
Message-ID: <20260702160248.1377250-8-maz@kernel.org> (raw)
In-Reply-To: <20260702160248.1377250-1-maz@kernel.org>
We currently avoid using the ERET fast path if the guest has HCR_EL2.NV
set. This is an odd check, as NV doesn't mean much if HCR_EL2.TGE==1.
Replace this bizarre check with is_nested_ctxt() which makes a lot
more sense: if we are running an L2, the ERET trap must go to L1.
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/kvm/hyp/vhe/switch.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c
index bbe9cebd3d9d5..3b76e0468317b 100644
--- a/arch/arm64/kvm/hyp/vhe/switch.c
+++ b/arch/arm64/kvm/hyp/vhe/switch.c
@@ -349,8 +349,8 @@ static bool kvm_hyp_handle_eret(struct kvm_vcpu *vcpu, u64 *exit_code)
* Unless the trap has to be forwarded further down the line,
* of course...
*/
- if ((__vcpu_sys_reg(vcpu, HCR_EL2) & HCR_NV) ||
- (__vcpu_sys_reg(vcpu, HFGITR_EL2) & HFGITR_EL2_ERET))
+ if (is_nested_ctxt(vcpu) ||
+ __vcpu_sys_reg(vcpu, HFGITR_EL2) & HFGITR_EL2_ERET)
return false;
spsr = read_sysreg_el1(SYS_SPSR);
--
2.47.3
next prev parent reply other threads:[~2026-07-02 18:26 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-02 16:02 [PATCH 00/28] KVM: arm64: Add support for FEAT_NV2p1 and FEAT_NV3 Marc Zyngier
2026-07-02 16:02 ` [PATCH 01/28] arm64: sysreg: Emit RESx/UNKN values for Mapping definitions Marc Zyngier
2026-07-02 16:02 ` [PATCH 02/28] arm64: Update ID_AA64MMFR4_EL1 description to 2026-03 JSON release Marc Zyngier
2026-07-02 16:02 ` [PATCH 03/28] KVM: arm64: Merge guest's HCRX_EL2 using NV_HCRX_GUEST_EXCLUDE Marc Zyngier
2026-07-02 16:02 ` [PATCH 04/28] KVM: arm64: Drop __HCRX_EL2_* masks Marc Zyngier
2026-07-02 16:02 ` [PATCH 05/28] KVM: arm64: Plumb HCRX_EL2.SRMASKEn in HCRX_EL2 sanitisation Marc Zyngier
2026-07-02 16:02 ` [PATCH 06/28] KVM: arm64: Classify CPTR_EL2 as a SR_LOC_SPECIAL register Marc Zyngier
2026-07-02 16:02 ` Marc Zyngier [this message]
2026-07-02 16:02 ` [PATCH 08/28] arm64: Add ARM64_HAS_NV2P1 capability Marc Zyngier
2026-07-02 16:02 ` [PATCH 09/28] KVM: arm64: Relax CPTR_EL2 handling when FEAT_NV2p1 is present Marc Zyngier
2026-07-02 16:02 ` [PATCH 10/28] KVM: arm64: Relax CNTHCTL_EL2 " Marc Zyngier
2026-07-02 16:02 ` [PATCH 11/28] KVM: arm64: Expose FEAT_NV2p1 to NV guests Marc Zyngier
2026-07-02 16:02 ` [PATCH 12/28] arm64: Add FEAT_NV2p1 detection Marc Zyngier
2026-07-02 16:02 ` [PATCH 13/28] arm64: sysreg: Add NVHCR_EL2 description as a mirror of HCR_EL2 Marc Zyngier
2026-07-02 16:02 ` [PATCH 14/28] arm64: sysreg: Add HCRX_EL2 bits related to FEAT_NV3 Marc Zyngier
2026-07-02 16:02 ` [PATCH 15/28] arm64: Add ARM64_HAS_NV3 capability Marc Zyngier
2026-07-02 16:02 ` [PATCH 16/28] KVM: arm64: Split NV-specific exit fixups from the non-NV handling Marc Zyngier
2026-07-02 16:02 ` [PATCH 17/28] KVM: arm64: Add NV3 control bits to HCRX_EL2 sanitisation Marc Zyngier
2026-07-02 16:02 ` [PATCH 18/28] KVM: arm64: Add kvm_has_nv{2,3}() predicates Marc Zyngier
2026-07-02 16:02 ` [PATCH 19/28] KVM: arm64: Make HCR_EL2 a non-VNCR register Marc Zyngier
2026-07-02 16:02 ` [PATCH 20/28] KVM: arm64: Add sanitisation for NVHCR_EL2 Marc Zyngier
2026-07-02 16:02 ` [PATCH 21/28] KVM: arm64: Add NVHCR_EL2 handling to the sysreg array Marc Zyngier
2026-07-02 16:02 ` [PATCH 22/28] KVM: arm64: Add routing for NVHCR_EL2 trap Marc Zyngier
2026-07-02 16:02 ` [PATCH 23/28] KVM: arm64: Add NVHCR_EL2 context switching Marc Zyngier
2026-07-02 16:02 ` [PATCH 24/28] KVM: arm64: Engage NV3 ERET trap elision Marc Zyngier
2026-07-02 16:02 ` [PATCH 25/28] KVM: arm64: Engage NV3 TLBI " Marc Zyngier
2026-07-02 16:02 ` [PATCH 26/28] KVM: arm64: Add FEAT_NV3 detection Marc Zyngier
2026-07-02 16:02 ` [PATCH 27/28] KVM: arm64: Expose FEAT_NV3 to guests Marc Zyngier
2026-07-02 16:02 ` [PATCH 28/28] arm64: Add override for ID_AA64MMFR4_EL1.NV_frac Marc Zyngier
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