From: Marc Zyngier maz@kernel.org
mainline inclusion from mainline-v5.13-rc1~76^2 commit 52029198c1cec1e21513d74f87363a0408f28650 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I8E73O CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
-------------------------------------------------
In order to keep the code readable, move the host-save/guest-restore sequences in their own functions, with the following changes: - the hypervisor ZCR is now set from C code - ZCR_EL2 is always used as the EL2 accessor
This results in some minor assembler macro rework. No functional change intended.
Acked-by: Will Deacon will@kernel.org Signed-off-by: Marc Zyngier maz@kernel.org Signed-off-by: Wang ShaoBo bobo.shaobowang@huawei.com --- arch/arm64/include/asm/fpsimdmacros.h | 8 +++-- arch/arm64/include/asm/kvm_hyp.h | 2 +- arch/arm64/kvm/hyp/fpsimd.S | 2 +- arch/arm64/kvm/hyp/include/hyp/switch.h | 40 +++++++++++++++---------- 4 files changed, 32 insertions(+), 20 deletions(-)
diff --git a/arch/arm64/include/asm/fpsimdmacros.h b/arch/arm64/include/asm/fpsimdmacros.h index f6a1cab3cea76..059204477ce66 100644 --- a/arch/arm64/include/asm/fpsimdmacros.h +++ b/arch/arm64/include/asm/fpsimdmacros.h @@ -234,8 +234,7 @@ str w\nxtmp, [\xpfpsr, #4] .endm
-.macro sve_load nxbase, xpfpsr, xvqminus1, nxtmp, xtmp2 - sve_load_vq \xvqminus1, x\nxtmp, \xtmp2 +.macro __sve_load nxbase, xpfpsr, nxtmp _for n, 0, 31, _sve_ldr_v \n, \nxbase, \n - 34 _sve_ldr_p 0, \nxbase _sve_wrffr 0 @@ -246,3 +245,8 @@ ldr w\nxtmp, [\xpfpsr, #4] msr fpcr, x\nxtmp .endm + +.macro sve_load nxbase, xpfpsr, xvqminus1, nxtmp, xtmp2 + sve_load_vq \xvqminus1, x\nxtmp, \xtmp2 + __sve_load \nxbase, \xpfpsr, \nxtmp +.endm diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h index 09942966707f1..1addcb3476f95 100644 --- a/arch/arm64/include/asm/kvm_hyp.h +++ b/arch/arm64/include/asm/kvm_hyp.h @@ -90,7 +90,7 @@ void __debug_restore_host_buffers_nvhe(struct kvm_vcpu *vcpu); void __fpsimd_save_state(struct user_fpsimd_state *fp_regs); void __fpsimd_restore_state(struct user_fpsimd_state *fp_regs); void __sve_save_state(void *sve_pffr, u32 *fpsr); -void __sve_restore_state(void *sve_pffr, u32 *fpsr, unsigned int vqminus1); +void __sve_restore_state(void *sve_pffr, u32 *fpsr);
#ifndef __KVM_NVHE_HYPERVISOR__ void activate_traps_vhe_load(struct kvm_vcpu *vcpu); diff --git a/arch/arm64/kvm/hyp/fpsimd.S b/arch/arm64/kvm/hyp/fpsimd.S index 95b22e10996cc..3c635929771a8 100644 --- a/arch/arm64/kvm/hyp/fpsimd.S +++ b/arch/arm64/kvm/hyp/fpsimd.S @@ -21,7 +21,7 @@ SYM_FUNC_START(__fpsimd_restore_state) SYM_FUNC_END(__fpsimd_restore_state)
SYM_FUNC_START(__sve_restore_state) - sve_load 0, x1, x2, 3, x4 + __sve_load 0, x1, 2 ret SYM_FUNC_END(__sve_restore_state)
diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h index 805b09831f085..20b52a17ac8f7 100644 --- a/arch/arm64/kvm/hyp/include/hyp/switch.h +++ b/arch/arm64/kvm/hyp/include/hyp/switch.h @@ -194,6 +194,24 @@ static inline bool __populate_fault_info(struct kvm_vcpu *vcpu) return true; }
+static inline void __hyp_sve_save_host(struct kvm_vcpu *vcpu) +{ + struct thread_struct *thread; + + thread = container_of(vcpu->arch.host_fpsimd_state, struct thread_struct, + uw.fpsimd_state); + + __sve_save_state(sve_pffr(thread), &vcpu->arch.host_fpsimd_state->fpsr); +} + +static inline void __hyp_sve_restore_guest(struct kvm_vcpu *vcpu) +{ + sve_cond_update_zcr_vq(vcpu_sve_max_vq(vcpu) - 1, SYS_ZCR_EL2); + __sve_restore_state(vcpu_sve_pffr(vcpu), + &vcpu->arch.ctxt.fp_regs.fpsr); + write_sysreg_el1(__vcpu_sys_reg(vcpu, ZCR_EL1), SYS_ZCR); +} + /* Check for an FPSIMD/SVE trap and handle as appropriate */ static inline bool __hyp_handle_fpsimd(struct kvm_vcpu *vcpu) { @@ -254,28 +272,18 @@ static inline bool __hyp_handle_fpsimd(struct kvm_vcpu *vcpu) * In the SVE case, VHE is assumed: it is enforced by * Kconfig and kvm_arch_init(). */ - if (sve_host) { - struct thread_struct *thread = container_of( - vcpu->arch.host_fpsimd_state, - struct thread_struct, uw.fpsimd_state); - - __sve_save_state(sve_pffr(thread), - &vcpu->arch.host_fpsimd_state->fpsr); - } else { + if (sve_host) + __hyp_sve_save_host(vcpu); + else __fpsimd_save_state(vcpu->arch.host_fpsimd_state); - }
vcpu->arch.flags &= ~KVM_ARM64_FP_HOST; }
- if (sve_guest) { - __sve_restore_state(vcpu_sve_pffr(vcpu), - &vcpu->arch.ctxt.fp_regs.fpsr, - vcpu_sve_max_vq(vcpu) - 1); - write_sysreg_el1(__vcpu_sys_reg(vcpu, ZCR_EL1), SYS_ZCR); - } else { + if (sve_guest) + __hyp_sve_restore_guest(vcpu); + else __fpsimd_restore_state(&vcpu->arch.ctxt.fp_regs); - }
/* Skip restoring fpexc32 for AArch64 guests */ if (!(read_sysreg(hcr_el2) & HCR_RW))