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linux/arch/arm64/kvm/hyp/switch.c

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arm64: KVM: Implement the core world switch Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-21 09:57:10 +01:00
/*
* Copyright (C) 2015 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
arm64: KVM: Move most of the fault decoding to C The fault decoding process (including computing the IPA in the case of a permission fault) would be much better done in C code, as we have a reasonable infrastructure to deal with the VHE/non-VHE differences. Let's move the whole thing to C, including the workaround for erratum 834220, and just patch the odd ESR_EL2 access remaining in hyp-entry.S. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-10-28 15:06:47 +00:00
#include <linux/types.h>
arm64: KVM: VHE: Implement VHE activate/deactivate_traps Running the kernel in HYP mode requires the HCR_E2H bit to be set at all times, and the HCR_TGE bit to be set when running as a host (and cleared when running as a guest). At the same time, the vector must be set to the current role of the kernel (either host or hypervisor), and a couple of system registers differ between VHE and non-VHE. We implement these by using another set of alternate functions that get dynamically patched. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-01-29 15:47:55 +00:00
#include <asm/kvm_asm.h>
arm64: KVM: Move kvm/hyp/hyp.h to include/asm/kvm_hyp.h In order to be able to move code outside of kvm/hyp, we need to make the global hyp.h file accessible from a standard location. include/asm/kvm_hyp.h seems good enough. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-01-28 13:44:07 +00:00
#include <asm/kvm_hyp.h>
arm64: KVM: Implement the core world switch Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-21 09:57:10 +01:00
arm64: KVM: VHE: Make __fpsimd_enabled VHE aware As non-VHE and VHE have different ways to express the trapping of FPSIMD registers to EL2, make __fpsimd_enabled a patchable predicate and provide a VHE implementation. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-10-28 14:15:45 +00:00
static bool __hyp_text __fpsimd_enabled_nvhe(void)
{
return !(read_sysreg(cptr_el2) & CPTR_EL2_TFP);
}
static bool __hyp_text __fpsimd_enabled_vhe(void)
{
return !!(read_sysreg(cpacr_el1) & CPACR_EL1_FPEN);
}
static hyp_alternate_select(__fpsimd_is_enabled,
__fpsimd_enabled_nvhe, __fpsimd_enabled_vhe,
ARM64_HAS_VIRT_HOST_EXTN);
bool __hyp_text __fpsimd_enabled(void)
{
return __fpsimd_is_enabled()();
}
arm64: KVM: VHE: Implement VHE activate/deactivate_traps Running the kernel in HYP mode requires the HCR_E2H bit to be set at all times, and the HCR_TGE bit to be set when running as a host (and cleared when running as a guest). At the same time, the vector must be set to the current role of the kernel (either host or hypervisor), and a couple of system registers differ between VHE and non-VHE. We implement these by using another set of alternate functions that get dynamically patched. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-01-29 15:47:55 +00:00
static void __hyp_text __activate_traps_vhe(void)
{
u64 val;
val = read_sysreg(cpacr_el1);
val |= CPACR_EL1_TTA;
val &= ~CPACR_EL1_FPEN;
write_sysreg(val, cpacr_el1);
write_sysreg(__kvm_hyp_vector, vbar_el1);
}
static void __hyp_text __activate_traps_nvhe(void)
{
u64 val;
val = CPTR_EL2_DEFAULT;
val |= CPTR_EL2_TTA | CPTR_EL2_TFP;
write_sysreg(val, cptr_el2);
}
static hyp_alternate_select(__activate_traps_arch,
__activate_traps_nvhe, __activate_traps_vhe,
ARM64_HAS_VIRT_HOST_EXTN);
arm64: KVM: Implement the core world switch Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-21 09:57:10 +01:00
static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu)
{
u64 val;
/*
* We are about to set CPTR_EL2.TFP to trap all floating point
* register accesses to EL2, however, the ARM ARM clearly states that
* traps are only taken to EL2 if the operation would not otherwise
* trap to EL1. Therefore, always make sure that for 32-bit guests,
* we set FPEXC.EN to prevent traps to EL1, when setting the TFP bit.
*/
val = vcpu->arch.hcr_el2;
if (!(val & HCR_RW)) {
write_sysreg(1 << 30, fpexc32_el2);
isb();
}
write_sysreg(val, hcr_el2);
/* Trap on AArch32 cp15 c15 accesses (EL1 or EL0) */
write_sysreg(1 << 15, hstr_el2);
arm64: KVM: Add access handler for PMUSERENR register This register resets as unknown in 64bit mode while it resets as zero in 32bit mode. Here we choose to reset it as zero for consistency. PMUSERENR_EL0 holds some bits which decide whether PMU registers can be accessed from EL0. Add some check helpers to handle the access from EL0. When these bits are zero, only reading PMUSERENR will trap to EL2 and writing PMUSERENR or reading/writing other PMU registers will trap to EL1 other than EL2 when HCR.TGE==0. To current KVM configuration (HCR.TGE==0) there is no way to get these traps. Here we write 0xf to physical PMUSERENR register on VM entry, so that it will trap PMU access from EL0 to EL2. Within the register access handler we check the real value of guest PMUSERENR register to decide whether this access is allowed. If not allowed, return false to inject UND to guest. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-09-08 15:15:56 +08:00
/* Make sure we trap PMU access from EL0 to EL2 */
write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0);
arm64: KVM: VHE: Implement VHE activate/deactivate_traps Running the kernel in HYP mode requires the HCR_E2H bit to be set at all times, and the HCR_TGE bit to be set when running as a host (and cleared when running as a guest). At the same time, the vector must be set to the current role of the kernel (either host or hypervisor), and a couple of system registers differ between VHE and non-VHE. We implement these by using another set of alternate functions that get dynamically patched. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-01-29 15:47:55 +00:00
write_sysreg(vcpu->arch.mdcr_el2, mdcr_el2);
__activate_traps_arch()();
}
arm64: KVM: Obey RES0/1 reserved bits when setting CPTR_EL2 Some bits in CPTR are defined as RES1 in the architecture. Setting these bits to zero may unintentionally enable future architecture extensions, allowing guests to use them without supervision by the host. This would be bad: for forwards compatibility, this patch makes sure the affected bits are always written with 1, not 0. This patch only addresses CPTR_EL2. Initialisation of other system registers may still need review. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-01-19 16:20:18 +00:00
arm64: KVM: VHE: Implement VHE activate/deactivate_traps Running the kernel in HYP mode requires the HCR_E2H bit to be set at all times, and the HCR_TGE bit to be set when running as a host (and cleared when running as a guest). At the same time, the vector must be set to the current role of the kernel (either host or hypervisor), and a couple of system registers differ between VHE and non-VHE. We implement these by using another set of alternate functions that get dynamically patched. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-01-29 15:47:55 +00:00
static void __hyp_text __deactivate_traps_vhe(void)
{
extern char vectors[]; /* kernel exception vectors */
arm64: KVM: Obey RES0/1 reserved bits when setting CPTR_EL2 Some bits in CPTR are defined as RES1 in the architecture. Setting these bits to zero may unintentionally enable future architecture extensions, allowing guests to use them without supervision by the host. This would be bad: for forwards compatibility, this patch makes sure the affected bits are always written with 1, not 0. This patch only addresses CPTR_EL2. Initialisation of other system registers may still need review. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-01-19 16:20:18 +00:00
arm64: KVM: VHE: Implement VHE activate/deactivate_traps Running the kernel in HYP mode requires the HCR_E2H bit to be set at all times, and the HCR_TGE bit to be set when running as a host (and cleared when running as a guest). At the same time, the vector must be set to the current role of the kernel (either host or hypervisor), and a couple of system registers differ between VHE and non-VHE. We implement these by using another set of alternate functions that get dynamically patched. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-01-29 15:47:55 +00:00
write_sysreg(HCR_HOST_VHE_FLAGS, hcr_el2);
write_sysreg(CPACR_EL1_FPEN, cpacr_el1);
write_sysreg(vectors, vbar_el1);
arm64: KVM: Implement the core world switch Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-21 09:57:10 +01:00
}
arm64: KVM: VHE: Implement VHE activate/deactivate_traps Running the kernel in HYP mode requires the HCR_E2H bit to be set at all times, and the HCR_TGE bit to be set when running as a host (and cleared when running as a guest). At the same time, the vector must be set to the current role of the kernel (either host or hypervisor), and a couple of system registers differ between VHE and non-VHE. We implement these by using another set of alternate functions that get dynamically patched. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-01-29 15:47:55 +00:00
static void __hyp_text __deactivate_traps_nvhe(void)
arm64: KVM: Implement the core world switch Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-21 09:57:10 +01:00
{
write_sysreg(HCR_RW, hcr_el2);
arm64: KVM: VHE: Implement VHE activate/deactivate_traps Running the kernel in HYP mode requires the HCR_E2H bit to be set at all times, and the HCR_TGE bit to be set when running as a host (and cleared when running as a guest). At the same time, the vector must be set to the current role of the kernel (either host or hypervisor), and a couple of system registers differ between VHE and non-VHE. We implement these by using another set of alternate functions that get dynamically patched. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-01-29 15:47:55 +00:00
write_sysreg(CPTR_EL2_DEFAULT, cptr_el2);
}
static hyp_alternate_select(__deactivate_traps_arch,
__deactivate_traps_nvhe, __deactivate_traps_vhe,
ARM64_HAS_VIRT_HOST_EXTN);
static void __hyp_text __deactivate_traps(struct kvm_vcpu *vcpu)
{
__deactivate_traps_arch()();
arm64: KVM: Implement the core world switch Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-21 09:57:10 +01:00
write_sysreg(0, hstr_el2);
write_sysreg(read_sysreg(mdcr_el2) & MDCR_EL2_HPMN_MASK, mdcr_el2);
arm64: KVM: Add access handler for PMUSERENR register This register resets as unknown in 64bit mode while it resets as zero in 32bit mode. Here we choose to reset it as zero for consistency. PMUSERENR_EL0 holds some bits which decide whether PMU registers can be accessed from EL0. Add some check helpers to handle the access from EL0. When these bits are zero, only reading PMUSERENR will trap to EL2 and writing PMUSERENR or reading/writing other PMU registers will trap to EL1 other than EL2 when HCR.TGE==0. To current KVM configuration (HCR.TGE==0) there is no way to get these traps. Here we write 0xf to physical PMUSERENR register on VM entry, so that it will trap PMU access from EL0 to EL2. Within the register access handler we check the real value of guest PMUSERENR register to decide whether this access is allowed. If not allowed, return false to inject UND to guest. Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-09-08 15:15:56 +08:00
write_sysreg(0, pmuserenr_el0);
arm64: KVM: Implement the core world switch Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-21 09:57:10 +01:00
}
static void __hyp_text __activate_vm(struct kvm_vcpu *vcpu)
{
struct kvm *kvm = kern_hyp_va(vcpu->kvm);
write_sysreg(kvm->arch.vttbr, vttbr_el2);
}
static void __hyp_text __deactivate_vm(struct kvm_vcpu *vcpu)
{
write_sysreg(0, vttbr_el2);
}
static hyp_alternate_select(__vgic_call_save_state,
__vgic_v2_save_state, __vgic_v3_save_state,
ARM64_HAS_SYSREG_GIC_CPUIF);
static hyp_alternate_select(__vgic_call_restore_state,
__vgic_v2_restore_state, __vgic_v3_restore_state,
ARM64_HAS_SYSREG_GIC_CPUIF);
static void __hyp_text __vgic_save_state(struct kvm_vcpu *vcpu)
{
__vgic_call_save_state()(vcpu);
write_sysreg(read_sysreg(hcr_el2) & ~HCR_INT_OVERRIDE, hcr_el2);
}
static void __hyp_text __vgic_restore_state(struct kvm_vcpu *vcpu)
{
u64 val;
val = read_sysreg(hcr_el2);
val |= HCR_INT_OVERRIDE;
val |= vcpu->arch.irq_lines;
write_sysreg(val, hcr_el2);
__vgic_call_restore_state()(vcpu);
}
arm64: KVM: Move most of the fault decoding to C The fault decoding process (including computing the IPA in the case of a permission fault) would be much better done in C code, as we have a reasonable infrastructure to deal with the VHE/non-VHE differences. Let's move the whole thing to C, including the workaround for erratum 834220, and just patch the odd ESR_EL2 access remaining in hyp-entry.S. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-10-28 15:06:47 +00:00
static bool __hyp_text __true_value(void)
{
return true;
}
static bool __hyp_text __false_value(void)
{
return false;
}
static hyp_alternate_select(__check_arm_834220,
__false_value, __true_value,
ARM64_WORKAROUND_834220);
static bool __hyp_text __translate_far_to_hpfar(u64 far, u64 *hpfar)
{
u64 par, tmp;
/*
* Resolve the IPA the hard way using the guest VA.
*
* Stage-1 translation already validated the memory access
* rights. As such, we can use the EL1 translation regime, and
* don't have to distinguish between EL0 and EL1 access.
*
* We do need to save/restore PAR_EL1 though, as we haven't
* saved the guest context yet, and we may return early...
*/
par = read_sysreg(par_el1);
asm volatile("at s1e1r, %0" : : "r" (far));
isb();
tmp = read_sysreg(par_el1);
write_sysreg(par, par_el1);
if (unlikely(tmp & 1))
return false; /* Translation failed, back to guest */
/* Convert PAR to HPFAR format */
*hpfar = ((tmp >> 12) & ((1UL << 36) - 1)) << 4;
return true;
}
static bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu)
{
u64 esr = read_sysreg_el2(esr);
u8 ec = esr >> ESR_ELx_EC_SHIFT;
u64 hpfar, far;
vcpu->arch.fault.esr_el2 = esr;
if (ec != ESR_ELx_EC_DABT_LOW && ec != ESR_ELx_EC_IABT_LOW)
return true;
far = read_sysreg_el2(far);
/*
* The HPFAR can be invalid if the stage 2 fault did not
* happen during a stage 1 page table walk (the ESR_EL2.S1PTW
* bit is clear) and one of the two following cases are true:
* 1. The fault was due to a permission fault
* 2. The processor carries errata 834220
*
* Therefore, for all non S1PTW faults where we either have a
* permission fault or the errata workaround is enabled, we
* resolve the IPA using the AT instruction.
*/
if (!(esr & ESR_ELx_S1PTW) &&
(__check_arm_834220()() || (esr & ESR_ELx_FSC_TYPE) == FSC_PERM)) {
if (!__translate_far_to_hpfar(far, &hpfar))
return false;
} else {
hpfar = read_sysreg(hpfar_el2);
}
vcpu->arch.fault.far_el2 = far;
vcpu->arch.fault.hpfar_el2 = hpfar;
return true;
}
arm64: KVM: Remove weak attributes As we've now switched to the new world switch implementation, remove the weak attributes, as nobody is supposed to override it anymore. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-10-26 09:10:07 +00:00
static int __hyp_text __guest_run(struct kvm_vcpu *vcpu)
arm64: KVM: Implement the core world switch Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-21 09:57:10 +01:00
{
struct kvm_cpu_context *host_ctxt;
struct kvm_cpu_context *guest_ctxt;
arm64: KVM: Implement fpsimd save/restore Implement the fpsimd save restore, keeping the lazy part in assembler (as returning to C would be overkill). Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-26 08:34:09 +00:00
bool fp_enabled;
arm64: KVM: Implement the core world switch Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-21 09:57:10 +01:00
u64 exit_code;
vcpu = kern_hyp_va(vcpu);
write_sysreg(vcpu, tpidr_el2);
host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context);
guest_ctxt = &vcpu->arch.ctxt;
arm64: KVM: VHE: Differenciate host/guest sysreg save/restore With ARMv8, host and guest share the same system register file, making the save/restore procedure completely symetrical. With VHE, host and guest now have different requirements, as they use different sysregs. In order to prepare for this, add split sysreg save/restore functions for both host and guest. No functional changes yet. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-10-28 12:17:35 +00:00
__sysreg_save_host_state(host_ctxt);
arm64: KVM: Implement the core world switch Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-21 09:57:10 +01:00
__debug_cond_save_host_state(vcpu);
__activate_traps(vcpu);
__activate_vm(vcpu);
__vgic_restore_state(vcpu);
__timer_restore_state(vcpu);
/*
* We must restore the 32-bit state before the sysregs, thanks
* to Cortex-A57 erratum #852523.
*/
__sysreg32_restore_state(vcpu);
arm64: KVM: VHE: Differenciate host/guest sysreg save/restore With ARMv8, host and guest share the same system register file, making the save/restore procedure completely symetrical. With VHE, host and guest now have different requirements, as they use different sysregs. In order to prepare for this, add split sysreg save/restore functions for both host and guest. No functional changes yet. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-10-28 12:17:35 +00:00
__sysreg_restore_guest_state(guest_ctxt);
arm64: KVM: Implement the core world switch Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-21 09:57:10 +01:00
__debug_restore_state(vcpu, kern_hyp_va(vcpu->arch.debug_ptr), guest_ctxt);
/* Jump in the fire! */
arm64: KVM: Move most of the fault decoding to C The fault decoding process (including computing the IPA in the case of a permission fault) would be much better done in C code, as we have a reasonable infrastructure to deal with the VHE/non-VHE differences. Let's move the whole thing to C, including the workaround for erratum 834220, and just patch the odd ESR_EL2 access remaining in hyp-entry.S. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-10-28 15:06:47 +00:00
again:
arm64: KVM: Implement the core world switch Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-21 09:57:10 +01:00
exit_code = __guest_enter(vcpu, host_ctxt);
/* And we're baaack! */
arm64: KVM: Move most of the fault decoding to C The fault decoding process (including computing the IPA in the case of a permission fault) would be much better done in C code, as we have a reasonable infrastructure to deal with the VHE/non-VHE differences. Let's move the whole thing to C, including the workaround for erratum 834220, and just patch the odd ESR_EL2 access remaining in hyp-entry.S. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-10-28 15:06:47 +00:00
if (exit_code == ARM_EXCEPTION_TRAP && !__populate_fault_info(vcpu))
goto again;
arm64: KVM: Implement fpsimd save/restore Implement the fpsimd save restore, keeping the lazy part in assembler (as returning to C would be overkill). Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-26 08:34:09 +00:00
fp_enabled = __fpsimd_enabled();
arm64: KVM: VHE: Differenciate host/guest sysreg save/restore With ARMv8, host and guest share the same system register file, making the save/restore procedure completely symetrical. With VHE, host and guest now have different requirements, as they use different sysregs. In order to prepare for this, add split sysreg save/restore functions for both host and guest. No functional changes yet. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-10-28 12:17:35 +00:00
__sysreg_save_guest_state(guest_ctxt);
arm64: KVM: Implement the core world switch Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-21 09:57:10 +01:00
__sysreg32_save_state(vcpu);
__timer_save_state(vcpu);
__vgic_save_state(vcpu);
__deactivate_traps(vcpu);
__deactivate_vm(vcpu);
arm64: KVM: VHE: Differenciate host/guest sysreg save/restore With ARMv8, host and guest share the same system register file, making the save/restore procedure completely symetrical. With VHE, host and guest now have different requirements, as they use different sysregs. In order to prepare for this, add split sysreg save/restore functions for both host and guest. No functional changes yet. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-10-28 12:17:35 +00:00
__sysreg_restore_host_state(host_ctxt);
arm64: KVM: Implement the core world switch Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-21 09:57:10 +01:00
arm64: KVM: Implement fpsimd save/restore Implement the fpsimd save restore, keeping the lazy part in assembler (as returning to C would be overkill). Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-26 08:34:09 +00:00
if (fp_enabled) {
__fpsimd_save_state(&guest_ctxt->gp_regs.fp_regs);
__fpsimd_restore_state(&host_ctxt->gp_regs.fp_regs);
}
arm64: KVM: Implement the core world switch Implement the core of the world switch in C. Not everything is there yet, and there is nothing to re-enter the world switch either. But this already outlines the code structure well enough. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-21 09:57:10 +01:00
__debug_save_state(vcpu, kern_hyp_va(vcpu->arch.debug_ptr), guest_ctxt);
__debug_cond_restore_host_state(vcpu);
return exit_code;
}
arm64: KVM: Add panic handling Add the panic handler, together with the small bits of assembly code to call the kernel's panic implementation. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-25 15:21:52 +00:00
arm64: KVM: Remove weak attributes As we've now switched to the new world switch implementation, remove the weak attributes, as nobody is supposed to override it anymore. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-10-26 09:10:07 +00:00
__alias(__guest_run) int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
arm64: KVM: Add compatibility aliases So far, we've implemented the new world switch with a completely different namespace, so that we could have both implementation compiled in. Let's take things one step further by adding weak aliases that have the same names as the original implementation. The weak attributes allows the new implementation to be overriden by the old one, and everything still work. At a later point, we'll be able to simply drop the old code, and everything will hopefully keep working, thanks to the aliases we have just added. This also saves us repainting all the callers. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-25 13:58:00 +00:00
arm64: KVM: Add panic handling Add the panic handler, together with the small bits of assembly code to call the kernel's panic implementation. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-25 15:21:52 +00:00
static const char __hyp_panic_string[] = "HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n";
arm64: KVM: VHE: Add alternative panic handling As the kernel fully runs in HYP when VHE is enabled, we can directly branch to the kernel's panic() implementation, and not perform an exception return. Add the alternative code to deal with this. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-11-17 14:07:45 +00:00
static void __hyp_text __hyp_call_panic_nvhe(u64 spsr, u64 elr, u64 par)
arm64: KVM: Add panic handling Add the panic handler, together with the small bits of assembly code to call the kernel's panic implementation. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-25 15:21:52 +00:00
{
unsigned long str_va = (unsigned long)__hyp_panic_string;
arm64: KVM: VHE: Add alternative panic handling As the kernel fully runs in HYP when VHE is enabled, we can directly branch to the kernel's panic() implementation, and not perform an exception return. Add the alternative code to deal with this. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-11-17 14:07:45 +00:00
__hyp_do_panic(hyp_kern_va(str_va),
spsr, elr,
read_sysreg(esr_el2), read_sysreg_el2(far),
read_sysreg(hpfar_el2), par,
(void *)read_sysreg(tpidr_el2));
}
static void __hyp_text __hyp_call_panic_vhe(u64 spsr, u64 elr, u64 par)
{
panic(__hyp_panic_string,
spsr, elr,
read_sysreg_el2(esr), read_sysreg_el2(far),
read_sysreg(hpfar_el2), par,
(void *)read_sysreg(tpidr_el2));
}
static hyp_alternate_select(__hyp_call_panic,
__hyp_call_panic_nvhe, __hyp_call_panic_vhe,
ARM64_HAS_VIRT_HOST_EXTN);
void __hyp_text __noreturn __hyp_panic(void)
{
u64 spsr = read_sysreg_el2(spsr);
u64 elr = read_sysreg_el2(elr);
arm64: KVM: Add panic handling Add the panic handler, together with the small bits of assembly code to call the kernel's panic implementation. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-25 15:21:52 +00:00
u64 par = read_sysreg(par_el1);
if (read_sysreg(vttbr_el2)) {
struct kvm_vcpu *vcpu;
struct kvm_cpu_context *host_ctxt;
vcpu = (struct kvm_vcpu *)read_sysreg(tpidr_el2);
host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context);
__deactivate_traps(vcpu);
__deactivate_vm(vcpu);
arm64: KVM: VHE: Differenciate host/guest sysreg save/restore With ARMv8, host and guest share the same system register file, making the save/restore procedure completely symetrical. With VHE, host and guest now have different requirements, as they use different sysregs. In order to prepare for this, add split sysreg save/restore functions for both host and guest. No functional changes yet. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-10-28 12:17:35 +00:00
__sysreg_restore_host_state(host_ctxt);
arm64: KVM: Add panic handling Add the panic handler, together with the small bits of assembly code to call the kernel's panic implementation. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-25 15:21:52 +00:00
}
/* Call panic for real */
arm64: KVM: VHE: Add alternative panic handling As the kernel fully runs in HYP when VHE is enabled, we can directly branch to the kernel's panic() implementation, and not perform an exception return. Add the alternative code to deal with this. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-11-17 14:07:45 +00:00
__hyp_call_panic()(spsr, elr, par);
arm64: KVM: Add panic handling Add the panic handler, together with the small bits of assembly code to call the kernel's panic implementation. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-10-25 15:21:52 +00:00
unreachable();
}
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