From da20bb4bc5e6cc2028d61ba5dceaf9147348f617 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Wed, 3 Jun 2026 12:06:15 +0100 Subject: [PATCH] KVM: arm64: pkvm: Save host FPMR in host cpu context Protected KVM stores most of the host's system register state in kvm_host_data::host_ctxt, which is an instance of struct kvm_cpu_context. As kvm_cpu_context::sys_regs[] has a slot for FPMR, we can store the host's FPMR there. Do so, and remove kvm_host_data::fpmr. Signed-off-by: Mark Rutland Reviewed-by: Vladimir Murzin Cc: Catalin Marinas Cc: Fuad Tabba Cc: James Morse Cc: Marc Zyngier Cc: Mark Brown Cc: Oliver Upton Cc: Will Deacon Signed-off-by: Will Deacon --- arch/arm64/include/asm/kvm_host.h | 3 --- arch/arm64/kvm/hyp/include/hyp/switch.h | 6 ++++-- arch/arm64/kvm/hyp/nvhe/hyp-main.c | 5 +++-- 3 files changed, 7 insertions(+), 7 deletions(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 851f6171751c0..0595644d6a3ab 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -778,9 +778,6 @@ struct kvm_host_data { */ struct cpu_sve_state *sve_state; - /* Used by pKVM only. */ - u64 fpmr; - /* Ownership of the FP regs */ enum { FP_STATE_FREE, diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h index 98b2976837b11..cc4d011a2b380 100644 --- a/arch/arm64/kvm/hyp/include/hyp/switch.h +++ b/arch/arm64/kvm/hyp/include/hyp/switch.h @@ -554,6 +554,8 @@ static inline void fpsimd_lazy_switch_to_host(struct kvm_vcpu *vcpu) static void kvm_hyp_save_fpsimd_host(struct kvm_vcpu *vcpu) { + struct kvm_cpu_context *hctxt = host_data_ptr(host_ctxt); + /* * Non-protected kvm relies on the host restoring its sve state. * Protected kvm restores the host's sve state as not to reveal that @@ -562,11 +564,11 @@ static void kvm_hyp_save_fpsimd_host(struct kvm_vcpu *vcpu) if (system_supports_sve()) { __hyp_sve_save_host(); } else { - __fpsimd_save_state(host_data_ptr(host_ctxt.fp_regs)); + __fpsimd_save_state(&hctxt->fp_regs); } if (kvm_has_fpmr(kern_hyp_va(vcpu->kvm))) - *host_data_ptr(fpmr) = read_sysreg_s(SYS_FPMR); + ctxt_sys_reg(hctxt, FPMR) = read_sysreg_s(SYS_FPMR); } diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c index 73f2e0221e703..3b2c00ca94089 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -66,6 +66,7 @@ static void fpsimd_sve_flush(void) static void fpsimd_sve_sync(struct kvm_vcpu *vcpu) { + struct kvm_cpu_context *hctxt = host_data_ptr(host_ctxt); bool has_fpmr; if (!guest_owns_fp_regs()) @@ -89,10 +90,10 @@ static void fpsimd_sve_sync(struct kvm_vcpu *vcpu) if (system_supports_sve()) __hyp_sve_restore_host(); else - __fpsimd_restore_state(host_data_ptr(host_ctxt.fp_regs)); + __fpsimd_restore_state(&hctxt->fp_regs); if (has_fpmr) - write_sysreg_s(*host_data_ptr(fpmr), SYS_FPMR); + write_sysreg_s(ctxt_sys_reg(hctxt, FPMR), SYS_FPMR); *host_data_ptr(fp_owner) = FP_STATE_HOST_OWNED; } -- 2.47.3