5.15-stable review patch. If anyone has any objections, please let me know.
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From: Fuad Tabba tabba@google.com
[ Upstream commit 2fd5b4b0e7b440602455b79977bfa64dea101e6c ]
Similar to VHE, calculate the value of cptr_el2 from scratch on activate traps. This removes the need to store cptr_el2 in every vcpu structure. Moreover, some traps, such as whether the guest owns the fp registers, need to be set on every vcpu run.
Reported-by: James Clark james.clark@linaro.org Fixes: 5294afdbf45a ("KVM: arm64: Exclude FP ownership from kvm_vcpu_arch") Signed-off-by: Fuad Tabba tabba@google.com Link: https://lore.kernel.org/r/20241216105057.579031-13-tabba@google.com Signed-off-by: Marc Zyngier maz@kernel.org Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm64/include/asm/kvm_host.h | 1 - arch/arm64/kvm/arm.c | 1 - arch/arm64/kvm/hyp/nvhe/switch.c | 35 ++++++++++++++++++++++++++--------- 3 files changed, 26 insertions(+), 11 deletions(-)
--- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -301,7 +301,6 @@ struct kvm_vcpu_arch { /* Values of trap registers for the guest. */ u64 hcr_el2; u64 mdcr_el2; - u64 cptr_el2;
/* Values of trap registers for the host before guest entry. */ u64 mdcr_el2_host; --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1138,7 +1138,6 @@ static int kvm_arch_vcpu_ioctl_vcpu_init }
vcpu_reset_hcr(vcpu); - vcpu->arch.cptr_el2 = CPTR_EL2_DEFAULT;
/* * Handle the "start in power-off" case. --- a/arch/arm64/kvm/hyp/nvhe/switch.c +++ b/arch/arm64/kvm/hyp/nvhe/switch.c @@ -34,21 +34,38 @@ DEFINE_PER_CPU(struct kvm_host_data, kvm DEFINE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt); DEFINE_PER_CPU(unsigned long, kvm_hyp_vector);
-static void __activate_traps(struct kvm_vcpu *vcpu) +static bool guest_owns_fp_regs(struct kvm_vcpu *vcpu) { - u64 val; + return vcpu->arch.flags & KVM_ARM64_FP_ENABLED; +}
- ___activate_traps(vcpu); - __activate_traps_common(vcpu); +static void __activate_cptr_traps(struct kvm_vcpu *vcpu) +{ + u64 val = CPTR_EL2_TAM; /* Same bit irrespective of E2H */
- val = vcpu->arch.cptr_el2; - val |= CPTR_EL2_TTA | CPTR_EL2_TAM; - if (!update_fp_enabled(vcpu)) { - val |= CPTR_EL2_TFP | CPTR_EL2_TZ; - __activate_traps_fpsimd32(vcpu); + /* !hVHE case upstream */ + if (1) { + val |= CPTR_EL2_TTA | CPTR_NVHE_EL2_RES1; + + if (!vcpu_has_sve(vcpu) || !guest_owns_fp_regs(vcpu)) + val |= CPTR_EL2_TZ; + + if (!guest_owns_fp_regs(vcpu)) + val |= CPTR_EL2_TFP; }
+ if (!guest_owns_fp_regs(vcpu)) + __activate_traps_fpsimd32(vcpu); + write_sysreg(val, cptr_el2); +} + +static void __activate_traps(struct kvm_vcpu *vcpu) +{ + ___activate_traps(vcpu); + __activate_traps_common(vcpu); + __activate_cptr_traps(vcpu); + write_sysreg(__this_cpu_read(kvm_hyp_vector), vbar_el2);
if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) {