From 688c50aa72f64ca21767486e5eef876ec23e418c Mon Sep 17 00:00:00 2001 From: Christoffer Dall Date: Wed, 4 Jan 2017 16:10:28 +0100 Subject: KVM: arm/arm64: Move timer save/restore out of the hyp code As we are about to be lazy with saving and restoring the timer registers, we prepare by moving all possible timer configuration logic out of the hyp code. All virtual timer registers can be programmed from EL1 and since the arch timer is always a level triggered interrupt we can safely do this with interrupts disabled in the host kernel on the way to the guest without taking vtimer interrupts in the host kernel (yet). The downside is that the cntvoff register can only be programmed from hyp mode, so we jump into hyp mode and back to program it. This is also safe, because the host kernel doesn't use the virtual timer in the KVM code. It may add a little performance performance penalty, but only until following commits where we move this operation to vcpu load/put. Signed-off-by: Christoffer Dall Reviewed-by: Marc Zyngier --- arch/arm/kvm/hyp/switch.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'arch/arm/kvm') diff --git a/arch/arm/kvm/hyp/switch.c b/arch/arm/kvm/hyp/switch.c index ebd2dd46adf7..330c9ce34ba5 100644 --- a/arch/arm/kvm/hyp/switch.c +++ b/arch/arm/kvm/hyp/switch.c @@ -174,7 +174,7 @@ int __hyp_text __kvm_vcpu_run(struct kvm_vcpu *vcpu) __activate_vm(vcpu); __vgic_restore_state(vcpu); - __timer_restore_state(vcpu); + __timer_enable_traps(vcpu); __sysreg_restore_state(guest_ctxt); __banked_restore_state(guest_ctxt); @@ -191,7 +191,8 @@ again: __banked_save_state(guest_ctxt); __sysreg_save_state(guest_ctxt); - __timer_save_state(vcpu); + __timer_disable_traps(vcpu); + __vgic_save_state(vcpu); __deactivate_traps(vcpu); @@ -237,7 +238,7 @@ void __hyp_text __noreturn __hyp_panic(int cause) vcpu = (struct kvm_vcpu *)read_sysreg(HTPIDR); host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context); - __timer_save_state(vcpu); + __timer_disable_traps(vcpu); __deactivate_traps(vcpu); __deactivate_vm(vcpu); __banked_restore_state(host_ctxt); -- cgit v1.2.1 From 74a64a981662ab34289b3c90f6f964aa38ec1d9f Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Sun, 29 Oct 2017 02:18:09 +0000 Subject: KVM: arm/arm64: Unify 32bit fault injection Both arm and arm64 implementations are capable of injecting faults, and yet have completely divergent implementations, leading to different bugs and reduced maintainability. Let's elect the arm64 version as the canonical one and move it into aarch32.c, which is common to both architectures. Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall --- arch/arm/kvm/emulate.c | 139 ------------------------------------------------- 1 file changed, 139 deletions(-) (limited to 'arch/arm/kvm') diff --git a/arch/arm/kvm/emulate.c b/arch/arm/kvm/emulate.c index 0064b86a2c87..cdff963f133a 100644 --- a/arch/arm/kvm/emulate.c +++ b/arch/arm/kvm/emulate.c @@ -165,145 +165,6 @@ unsigned long *vcpu_spsr(struct kvm_vcpu *vcpu) * Inject exceptions into the guest */ -static u32 exc_vector_base(struct kvm_vcpu *vcpu) -{ - u32 sctlr = vcpu_cp15(vcpu, c1_SCTLR); - u32 vbar = vcpu_cp15(vcpu, c12_VBAR); - - if (sctlr & SCTLR_V) - return 0xffff0000; - else /* always have security exceptions */ - return vbar; -} - -/* - * Switch to an exception mode, updating both CPSR and SPSR. Follow - * the logic described in AArch32.EnterMode() from the ARMv8 ARM. - */ -static void kvm_update_psr(struct kvm_vcpu *vcpu, unsigned long mode) -{ - unsigned long cpsr = *vcpu_cpsr(vcpu); - u32 sctlr = vcpu_cp15(vcpu, c1_SCTLR); - - *vcpu_cpsr(vcpu) = (cpsr & ~MODE_MASK) | mode; - - switch (mode) { - case FIQ_MODE: - *vcpu_cpsr(vcpu) |= PSR_F_BIT; - /* Fall through */ - case ABT_MODE: - case IRQ_MODE: - *vcpu_cpsr(vcpu) |= PSR_A_BIT; - /* Fall through */ - default: - *vcpu_cpsr(vcpu) |= PSR_I_BIT; - } - - *vcpu_cpsr(vcpu) &= ~(PSR_IT_MASK | PSR_J_BIT | PSR_E_BIT | PSR_T_BIT); - - if (sctlr & SCTLR_TE) - *vcpu_cpsr(vcpu) |= PSR_T_BIT; - if (sctlr & SCTLR_EE) - *vcpu_cpsr(vcpu) |= PSR_E_BIT; - - /* Note: These now point to the mode banked copies */ - *vcpu_spsr(vcpu) = cpsr; -} - -/** - * kvm_inject_undefined - inject an undefined exception into the guest - * @vcpu: The VCPU to receive the undefined exception - * - * It is assumed that this code is called from the VCPU thread and that the - * VCPU therefore is not currently executing guest code. - * - * Modelled after TakeUndefInstrException() pseudocode. - */ -void kvm_inject_undefined(struct kvm_vcpu *vcpu) -{ - unsigned long cpsr = *vcpu_cpsr(vcpu); - bool is_thumb = (cpsr & PSR_T_BIT); - u32 vect_offset = 4; - u32 return_offset = (is_thumb) ? 2 : 4; - - kvm_update_psr(vcpu, UND_MODE); - *vcpu_reg(vcpu, 14) = *vcpu_pc(vcpu) - return_offset; - - /* Branch to exception vector */ - *vcpu_pc(vcpu) = exc_vector_base(vcpu) + vect_offset; -} - -/* - * Modelled after TakeDataAbortException() and TakePrefetchAbortException - * pseudocode. - */ -static void inject_abt(struct kvm_vcpu *vcpu, bool is_pabt, unsigned long addr) -{ - unsigned long cpsr = *vcpu_cpsr(vcpu); - bool is_thumb = (cpsr & PSR_T_BIT); - u32 vect_offset; - u32 return_offset = (is_thumb) ? 4 : 0; - bool is_lpae; - - kvm_update_psr(vcpu, ABT_MODE); - *vcpu_reg(vcpu, 14) = *vcpu_pc(vcpu) + return_offset; - - if (is_pabt) - vect_offset = 12; - else - vect_offset = 16; - - /* Branch to exception vector */ - *vcpu_pc(vcpu) = exc_vector_base(vcpu) + vect_offset; - - if (is_pabt) { - /* Set IFAR and IFSR */ - vcpu_cp15(vcpu, c6_IFAR) = addr; - is_lpae = (vcpu_cp15(vcpu, c2_TTBCR) >> 31); - /* Always give debug fault for now - should give guest a clue */ - if (is_lpae) - vcpu_cp15(vcpu, c5_IFSR) = 1 << 9 | 0x22; - else - vcpu_cp15(vcpu, c5_IFSR) = 2; - } else { /* !iabt */ - /* Set DFAR and DFSR */ - vcpu_cp15(vcpu, c6_DFAR) = addr; - is_lpae = (vcpu_cp15(vcpu, c2_TTBCR) >> 31); - /* Always give debug fault for now - should give guest a clue */ - if (is_lpae) - vcpu_cp15(vcpu, c5_DFSR) = 1 << 9 | 0x22; - else - vcpu_cp15(vcpu, c5_DFSR) = 2; - } - -} - -/** - * kvm_inject_dabt - inject a data abort into the guest - * @vcpu: The VCPU to receive the undefined exception - * @addr: The address to report in the DFAR - * - * It is assumed that this code is called from the VCPU thread and that the - * VCPU therefore is not currently executing guest code. - */ -void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr) -{ - inject_abt(vcpu, false, addr); -} - -/** - * kvm_inject_pabt - inject a prefetch abort into the guest - * @vcpu: The VCPU to receive the undefined exception - * @addr: The address to report in the DFAR - * - * It is assumed that this code is called from the VCPU thread and that the - * VCPU therefore is not currently executing guest code. - */ -void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr) -{ - inject_abt(vcpu, true, addr); -} - /** * kvm_inject_vabt - inject an async abort / SError into the guest * @vcpu: The VCPU to receive the exception -- cgit v1.2.1