From 1f742679c33bc083722cb0b442a95d458c491b56 Mon Sep 17 00:00:00 2001 From: James Morse Date: Mon, 8 Jan 2018 15:38:07 +0000 Subject: [PATCH] KVM: arm64: Stop save/restoring host tpidr_el1 on VHE Now that a VHE host uses tpidr_el2 for the cpu offset we no longer need KVM to save/restore tpidr_el1. Move this from the 'common' code into the non-vhe code. While we're at it, on VHE we don't need to save the ELR or SPSR as kernel_entry in entry.S will have pushed these onto the kernel stack, and will restore them from there. Move these to the non-vhe code as we need them to get back to the host. Finally remove the always-copy-tpidr we hid in the stage2 setup code, cpufeature's enable callback will do this for VHE, we only need KVM to do it for non-vhe. Add the copy into kvm-init instead. Signed-off-by: James Morse Reviewed-by: Christoffer Dall Signed-off-by: Catalin Marinas --- arch/arm64/kvm/hyp-init.S | 4 ++++ arch/arm64/kvm/hyp/s2-setup.c | 3 --- arch/arm64/kvm/hyp/sysreg-sr.c | 16 ++++++++-------- 3 files changed, 12 insertions(+), 11 deletions(-) diff --git a/arch/arm64/kvm/hyp-init.S b/arch/arm64/kvm/hyp-init.S index 33c40b3eea01..8a00de187e56 100644 --- a/arch/arm64/kvm/hyp-init.S +++ b/arch/arm64/kvm/hyp-init.S @@ -120,6 +120,10 @@ CPU_BE( orr x4, x4, #SCTLR_ELx_EE) kern_hyp_va x2 msr vbar_el2, x2 + /* copy tpidr_el1 into tpidr_el2 for use by HYP */ + mrs x1, tpidr_el1 + msr tpidr_el2, x1 + /* Hello, World! */ eret ENDPROC(__kvm_hyp_init) diff --git a/arch/arm64/kvm/hyp/s2-setup.c b/arch/arm64/kvm/hyp/s2-setup.c index 74306c33a6de..603e1ee83e89 100644 --- a/arch/arm64/kvm/hyp/s2-setup.c +++ b/arch/arm64/kvm/hyp/s2-setup.c @@ -86,8 +86,5 @@ u32 __hyp_text __init_stage2_translation(void) write_sysreg(val, vtcr_el2); - /* copy tpidr_el1 into tpidr_el2 for use by HYP */ - write_sysreg(read_sysreg(tpidr_el1), tpidr_el2); - return parange; } diff --git a/arch/arm64/kvm/hyp/sysreg-sr.c b/arch/arm64/kvm/hyp/sysreg-sr.c index 934137647837..c54cc2afb92b 100644 --- a/arch/arm64/kvm/hyp/sysreg-sr.c +++ b/arch/arm64/kvm/hyp/sysreg-sr.c @@ -27,8 +27,8 @@ static void __hyp_text __sysreg_do_nothing(struct kvm_cpu_context *ctxt) { } /* * Non-VHE: Both host and guest must save everything. * - * VHE: Host must save tpidr*_el[01], actlr_el1, mdscr_el1, sp0, pc, - * pstate, and guest must save everything. + * VHE: Host must save tpidr*_el0, actlr_el1, mdscr_el1, sp_el0, + * and guest must save everything. */ static void __hyp_text __sysreg_save_common_state(struct kvm_cpu_context *ctxt) @@ -36,11 +36,8 @@ static void __hyp_text __sysreg_save_common_state(struct kvm_cpu_context *ctxt) ctxt->sys_regs[ACTLR_EL1] = read_sysreg(actlr_el1); ctxt->sys_regs[TPIDR_EL0] = read_sysreg(tpidr_el0); ctxt->sys_regs[TPIDRRO_EL0] = read_sysreg(tpidrro_el0); - ctxt->sys_regs[TPIDR_EL1] = read_sysreg(tpidr_el1); ctxt->sys_regs[MDSCR_EL1] = read_sysreg(mdscr_el1); ctxt->gp_regs.regs.sp = read_sysreg(sp_el0); - ctxt->gp_regs.regs.pc = read_sysreg_el2(elr); - ctxt->gp_regs.regs.pstate = read_sysreg_el2(spsr); } static void __hyp_text __sysreg_save_state(struct kvm_cpu_context *ctxt) @@ -62,10 +59,13 @@ static void __hyp_text __sysreg_save_state(struct kvm_cpu_context *ctxt) ctxt->sys_regs[AMAIR_EL1] = read_sysreg_el1(amair); ctxt->sys_regs[CNTKCTL_EL1] = read_sysreg_el1(cntkctl); ctxt->sys_regs[PAR_EL1] = read_sysreg(par_el1); + ctxt->sys_regs[TPIDR_EL1] = read_sysreg(tpidr_el1); ctxt->gp_regs.sp_el1 = read_sysreg(sp_el1); ctxt->gp_regs.elr_el1 = read_sysreg_el1(elr); ctxt->gp_regs.spsr[KVM_SPSR_EL1]= read_sysreg_el1(spsr); + ctxt->gp_regs.regs.pc = read_sysreg_el2(elr); + ctxt->gp_regs.regs.pstate = read_sysreg_el2(spsr); } static hyp_alternate_select(__sysreg_call_save_host_state, @@ -89,11 +89,8 @@ static void __hyp_text __sysreg_restore_common_state(struct kvm_cpu_context *ctx write_sysreg(ctxt->sys_regs[ACTLR_EL1], actlr_el1); write_sysreg(ctxt->sys_regs[TPIDR_EL0], tpidr_el0); write_sysreg(ctxt->sys_regs[TPIDRRO_EL0], tpidrro_el0); - write_sysreg(ctxt->sys_regs[TPIDR_EL1], tpidr_el1); write_sysreg(ctxt->sys_regs[MDSCR_EL1], mdscr_el1); write_sysreg(ctxt->gp_regs.regs.sp, sp_el0); - write_sysreg_el2(ctxt->gp_regs.regs.pc, elr); - write_sysreg_el2(ctxt->gp_regs.regs.pstate, spsr); } static void __hyp_text __sysreg_restore_state(struct kvm_cpu_context *ctxt) @@ -115,10 +112,13 @@ static void __hyp_text __sysreg_restore_state(struct kvm_cpu_context *ctxt) write_sysreg_el1(ctxt->sys_regs[AMAIR_EL1], amair); write_sysreg_el1(ctxt->sys_regs[CNTKCTL_EL1], cntkctl); write_sysreg(ctxt->sys_regs[PAR_EL1], par_el1); + write_sysreg(ctxt->sys_regs[TPIDR_EL1], tpidr_el1); write_sysreg(ctxt->gp_regs.sp_el1, sp_el1); write_sysreg_el1(ctxt->gp_regs.elr_el1, elr); write_sysreg_el1(ctxt->gp_regs.spsr[KVM_SPSR_EL1],spsr); + write_sysreg_el2(ctxt->gp_regs.regs.pc, elr); + write_sysreg_el2(ctxt->gp_regs.regs.pstate, spsr); } static hyp_alternate_select(__sysreg_call_restore_host_state,