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Diffstat (limited to 'arch/arm64/kernel/hyp-stub.S')
| -rw-r--r-- | arch/arm64/kernel/hyp-stub.S | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S new file mode 100644 index 000000000..160f5881a --- /dev/null +++ b/arch/arm64/kernel/hyp-stub.S @@ -0,0 +1,120 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Hypervisor stub + * + * Copyright (C) 2012 ARM Ltd. + * Author: Marc Zyngier <marc.zyngier@arm.com> + */ + +#include <linux/init.h> +#include <linux/linkage.h> +#include <linux/irqchip/arm-gic-v3.h> + +#include <asm/assembler.h> +#include <asm/kvm_arm.h> +#include <asm/kvm_asm.h> +#include <asm/ptrace.h> +#include <asm/virt.h> + + .text + .pushsection .hyp.text, "ax" + + .align 11 + +SYM_CODE_START(__hyp_stub_vectors) + ventry el2_sync_invalid // Synchronous EL2t + ventry el2_irq_invalid // IRQ EL2t + ventry el2_fiq_invalid // FIQ EL2t + ventry el2_error_invalid // Error EL2t + + ventry el2_sync_invalid // Synchronous EL2h + ventry el2_irq_invalid // IRQ EL2h + ventry el2_fiq_invalid // FIQ EL2h + ventry el2_error_invalid // Error EL2h + + ventry el1_sync // Synchronous 64-bit EL1 + ventry el1_irq_invalid // IRQ 64-bit EL1 + ventry el1_fiq_invalid // FIQ 64-bit EL1 + ventry el1_error_invalid // Error 64-bit EL1 + + ventry el1_sync_invalid // Synchronous 32-bit EL1 + ventry el1_irq_invalid // IRQ 32-bit EL1 + ventry el1_fiq_invalid // FIQ 32-bit EL1 + ventry el1_error_invalid // Error 32-bit EL1 +SYM_CODE_END(__hyp_stub_vectors) + + .align 11 + +SYM_CODE_START_LOCAL(el1_sync) + cmp x0, #HVC_SET_VECTORS + b.ne 2f + msr vbar_el2, x1 + b 9f + +2: cmp x0, #HVC_SOFT_RESTART + b.ne 3f + mov x0, x2 + mov x2, x4 + mov x4, x1 + mov x1, x3 + br x4 // no return + +3: cmp x0, #HVC_RESET_VECTORS + beq 9f // Nothing to reset! + + /* Someone called kvm_call_hyp() against the hyp-stub... */ + mov_q x0, HVC_STUB_ERR + eret + +9: mov x0, xzr + eret +SYM_CODE_END(el1_sync) + +.macro invalid_vector label +SYM_CODE_START_LOCAL(\label) + b \label +SYM_CODE_END(\label) +.endm + + invalid_vector el2_sync_invalid + invalid_vector el2_irq_invalid + invalid_vector el2_fiq_invalid + invalid_vector el2_error_invalid + invalid_vector el1_sync_invalid + invalid_vector el1_irq_invalid + invalid_vector el1_fiq_invalid + invalid_vector el1_error_invalid + +/* + * __hyp_set_vectors: Call this after boot to set the initial hypervisor + * vectors as part of hypervisor installation. On an SMP system, this should + * be called on each CPU. + * + * x0 must be the physical address of the new vector table, and must be + * 2KB aligned. + * + * Before calling this, you must check that the stub hypervisor is installed + * everywhere, by waiting for any secondary CPUs to be brought up and then + * checking that is_hyp_mode_available() is true. + * + * If not, there is a pre-existing hypervisor, some CPUs failed to boot, or + * something else went wrong... in such cases, trying to install a new + * hypervisor is unlikely to work as desired. + * + * When you call into your shiny new hypervisor, sp_el2 will contain junk, + * so you will need to set that to something sensible at the new hypervisor's + * initialisation entry point. + */ + +SYM_FUNC_START(__hyp_set_vectors) + mov x1, x0 + mov x0, #HVC_SET_VECTORS + hvc #0 + ret +SYM_FUNC_END(__hyp_set_vectors) + +SYM_FUNC_START(__hyp_reset_vectors) + mov x0, #HVC_RESET_VECTORS + hvc #0 + ret +SYM_FUNC_END(__hyp_reset_vectors) |