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diff --git a/arch/arm64/kvm/hyp/nvhe/host.S b/arch/arm64/kvm/hyp/nvhe/host.S
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020 - Google Inc
+ * Author: Andrew Scull <ascull@google.com>
+ */
+
+#include <linux/linkage.h>
+
+#include <asm/assembler.h>
+#include <asm/kvm_asm.h>
+#include <asm/kvm_mmu.h>
+
+ .text
+
+SYM_FUNC_START(__host_exit)
+ stp x0, x1, [sp, #-16]!
+
+ get_host_ctxt x0, x1
+
+ /* Store the host regs x2 and x3 */
+ stp x2, x3, [x0, #CPU_XREG_OFFSET(2)]
+
+ /* Retrieve the host regs x0-x1 from the stack */
+ ldp x2, x3, [sp], #16 // x0, x1
+
+ /* Store the host regs x0-x1 and x4-x17 */
+ stp x2, x3, [x0, #CPU_XREG_OFFSET(0)]
+ stp x4, x5, [x0, #CPU_XREG_OFFSET(4)]
+ stp x6, x7, [x0, #CPU_XREG_OFFSET(6)]
+ stp x8, x9, [x0, #CPU_XREG_OFFSET(8)]
+ stp x10, x11, [x0, #CPU_XREG_OFFSET(10)]
+ stp x12, x13, [x0, #CPU_XREG_OFFSET(12)]
+ stp x14, x15, [x0, #CPU_XREG_OFFSET(14)]
+ stp x16, x17, [x0, #CPU_XREG_OFFSET(16)]
+
+ /* Store the host regs x18-x29, lr */
+ save_callee_saved_regs x0
+
+ /* Save the host context pointer in x29 across the function call */
+ mov x29, x0
+ bl handle_trap
+
+ /* Restore host regs x0-x17 */
+ ldp x0, x1, [x29, #CPU_XREG_OFFSET(0)]
+ ldp x2, x3, [x29, #CPU_XREG_OFFSET(2)]
+ ldp x4, x5, [x29, #CPU_XREG_OFFSET(4)]
+ ldp x6, x7, [x29, #CPU_XREG_OFFSET(6)]
+
+ /* x0-7 are use for panic arguments */
+__host_enter_for_panic:
+ ldp x8, x9, [x29, #CPU_XREG_OFFSET(8)]
+ ldp x10, x11, [x29, #CPU_XREG_OFFSET(10)]
+ ldp x12, x13, [x29, #CPU_XREG_OFFSET(12)]
+ ldp x14, x15, [x29, #CPU_XREG_OFFSET(14)]
+ ldp x16, x17, [x29, #CPU_XREG_OFFSET(16)]
+
+ /* Restore host regs x18-x29, lr */
+ restore_callee_saved_regs x29
+
+ /* Do not touch any register after this! */
+__host_enter_without_restoring:
+ eret
+ sb
+SYM_FUNC_END(__host_exit)
+
+/*
+ * void __noreturn __hyp_do_panic(struct kvm_cpu_context *host_ctxt, u64 spsr,
+ * u64 elr, u64 par);
+ */
+SYM_FUNC_START(__hyp_do_panic)
+ mov x29, x0
+
+ /* Load the format string into x0 and arguments into x1-7 */
+ ldr x0, =__hyp_panic_string
+
+ mov x6, x3
+ get_vcpu_ptr x7, x3
+
+ mrs x3, esr_el2
+ mrs x4, far_el2
+ mrs x5, hpfar_el2
+
+ /* Prepare and exit to the host's panic funciton. */
+ mov lr, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT |\
+ PSR_MODE_EL1h)
+ msr spsr_el2, lr
+ ldr lr, =panic
+ msr elr_el2, lr
+
+ /* Enter the host, conditionally restoring the host context. */
+ cbz x29, __host_enter_without_restoring
+ b __host_enter_for_panic
+SYM_FUNC_END(__hyp_do_panic)
+
+.macro host_el1_sync_vect
+ .align 7
+.L__vect_start\@:
+ stp x0, x1, [sp, #-16]!
+ mrs x0, esr_el2
+ ubfx x0, x0, #ESR_ELx_EC_SHIFT, #ESR_ELx_EC_WIDTH
+ cmp x0, #ESR_ELx_EC_HVC64
+ ldp x0, x1, [sp], #16
+ b.ne __host_exit
+
+ /* Check for a stub HVC call */
+ cmp x0, #HVC_STUB_HCALL_NR
+ b.hs __host_exit
+
+ /*
+ * Compute the idmap address of __kvm_handle_stub_hvc and
+ * jump there. Since we use kimage_voffset, do not use the
+ * HYP VA for __kvm_handle_stub_hvc, but the kernel VA instead
+ * (by loading it from the constant pool).
+ *
+ * Preserve x0-x4, which may contain stub parameters.
+ */
+ ldr x5, =__kvm_handle_stub_hvc
+ ldr_l x6, kimage_voffset
+
+ /* x5 = __pa(x5) */
+ sub x5, x5, x6
+ br x5
+.L__vect_end\@:
+.if ((.L__vect_end\@ - .L__vect_start\@) > 0x80)
+ .error "host_el1_sync_vect larger than vector entry"
+.endif
+.endm
+
+.macro invalid_host_el2_vect
+ .align 7
+ /* If a guest is loaded, panic out of it. */
+ stp x0, x1, [sp, #-16]!
+ get_loaded_vcpu x0, x1
+ cbnz x0, __guest_exit_panic
+ add sp, sp, #16
+
+ /*
+ * The panic may not be clean if the exception is taken before the host
+ * context has been saved by __host_exit or after the hyp context has
+ * been partially clobbered by __host_enter.
+ */
+ b hyp_panic
+.endm
+
+.macro invalid_host_el1_vect
+ .align 7
+ mov x0, xzr /* host_ctxt = NULL */
+ mrs x1, spsr_el2
+ mrs x2, elr_el2
+ mrs x3, par_el1
+ b __hyp_do_panic
+.endm
+
+/*
+ * The host vector does not use an ESB instruction in order to avoid consuming
+ * SErrors that should only be consumed by the host. Guest entry is deferred by
+ * __guest_enter if there are any pending asynchronous exceptions so hyp will
+ * always return to the host without having consumerd host SErrors.
+ *
+ * CONFIG_KVM_INDIRECT_VECTORS is not applied to the host vectors because the
+ * host knows about the EL2 vectors already, and there is no point in hiding
+ * them.
+ */
+ .align 11
+SYM_CODE_START(__kvm_hyp_host_vector)
+ invalid_host_el2_vect // Synchronous EL2t
+ invalid_host_el2_vect // IRQ EL2t
+ invalid_host_el2_vect // FIQ EL2t
+ invalid_host_el2_vect // Error EL2t
+
+ invalid_host_el2_vect // Synchronous EL2h
+ invalid_host_el2_vect // IRQ EL2h
+ invalid_host_el2_vect // FIQ EL2h
+ invalid_host_el2_vect // Error EL2h
+
+ host_el1_sync_vect // Synchronous 64-bit EL1
+ invalid_host_el1_vect // IRQ 64-bit EL1
+ invalid_host_el1_vect // FIQ 64-bit EL1
+ invalid_host_el1_vect // Error 64-bit EL1
+
+ invalid_host_el1_vect // Synchronous 32-bit EL1
+ invalid_host_el1_vect // IRQ 32-bit EL1
+ invalid_host_el1_vect // FIQ 32-bit EL1
+ invalid_host_el1_vect // Error 32-bit EL1
+SYM_CODE_END(__kvm_hyp_host_vector)