linux-stable/arch/arm64/kernel/image-vars.h
James Morse e9ee186bb7 KVM: arm64: Add kvm_extable for vaxorcism code
KVM has a one instruction window where it will allow an SError exception
to be consumed by the hypervisor without treating it as a hypervisor bug.
This is used to consume asynchronous external abort that were caused by
the guest.

As we are about to add another location that survives unexpected exceptions,
generalise this code to make it behave like the host's extable.

KVM's version has to be mapped to EL2 to be accessible on nVHE systems.

The SError vaxorcism code is a one instruction window, so has two entries
in the extable. Because the KVM code is copied for VHE and nVHE, we end up
with four entries, half of which correspond with code that isn't mapped.

Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-08-28 15:23:42 +01:00

112 lines
3.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Linker script variables to be set after section resolution, as
* ld.lld does not like variables assigned before SECTIONS is processed.
*/
#ifndef __ARM64_KERNEL_IMAGE_VARS_H
#define __ARM64_KERNEL_IMAGE_VARS_H
#ifndef LINKER_SCRIPT
#error This file should only be included in vmlinux.lds.S
#endif
#ifdef CONFIG_EFI
__efistub_kernel_size = _edata - _text;
__efistub_primary_entry_offset = primary_entry - _text;
/*
* The EFI stub has its own symbol namespace prefixed by __efistub_, to
* isolate it from the kernel proper. The following symbols are legally
* accessed by the stub, so provide some aliases to make them accessible.
* Only include data symbols here, or text symbols of functions that are
* guaranteed to be safe when executed at another offset than they were
* linked at. The routines below are all implemented in assembler in a
* position independent manner
*/
__efistub_memcmp = __pi_memcmp;
__efistub_memchr = __pi_memchr;
__efistub_memcpy = __pi_memcpy;
__efistub_memmove = __pi_memmove;
__efistub_memset = __pi_memset;
__efistub_strlen = __pi_strlen;
__efistub_strnlen = __pi_strnlen;
__efistub_strcmp = __pi_strcmp;
__efistub_strncmp = __pi_strncmp;
__efistub_strrchr = __pi_strrchr;
__efistub___clean_dcache_area_poc = __pi___clean_dcache_area_poc;
#ifdef CONFIG_KASAN
__efistub___memcpy = __pi_memcpy;
__efistub___memmove = __pi_memmove;
__efistub___memset = __pi_memset;
#endif
__efistub__text = _text;
__efistub__end = _end;
__efistub__edata = _edata;
__efistub_screen_info = screen_info;
__efistub__ctype = _ctype;
#endif
#ifdef CONFIG_KVM
/*
* KVM nVHE code has its own symbol namespace prefixed with __kvm_nvhe_, to
* separate it from the kernel proper. The following symbols are legally
* accessed by it, therefore provide aliases to make them linkable.
* Do not include symbols which may not be safely accessed under hypervisor
* memory mappings.
*/
#define KVM_NVHE_ALIAS(sym) __kvm_nvhe_##sym = sym;
/* Alternative callbacks for init-time patching of nVHE hyp code. */
KVM_NVHE_ALIAS(arm64_enable_wa2_handling);
KVM_NVHE_ALIAS(kvm_patch_vector_branch);
KVM_NVHE_ALIAS(kvm_update_va_mask);
/* Global kernel state accessed by nVHE hyp code. */
KVM_NVHE_ALIAS(arm64_ssbd_callback_required);
KVM_NVHE_ALIAS(kvm_host_data);
KVM_NVHE_ALIAS(kvm_vgic_global_state);
/* Kernel constant needed to compute idmap addresses. */
KVM_NVHE_ALIAS(kimage_voffset);
/* Kernel symbols used to call panic() from nVHE hyp code (via ERET). */
KVM_NVHE_ALIAS(__hyp_panic_string);
KVM_NVHE_ALIAS(panic);
/* Vectors installed by hyp-init on reset HVC. */
KVM_NVHE_ALIAS(__hyp_stub_vectors);
/* IDMAP TCR_EL1.T0SZ as computed by the EL1 init code */
KVM_NVHE_ALIAS(idmap_t0sz);
/* Kernel symbol used by icache_is_vpipt(). */
KVM_NVHE_ALIAS(__icache_flags);
/* Kernel symbols needed for cpus_have_final/const_caps checks. */
KVM_NVHE_ALIAS(arm64_const_caps_ready);
KVM_NVHE_ALIAS(cpu_hwcap_keys);
KVM_NVHE_ALIAS(cpu_hwcaps);
/* Static keys which are set if a vGIC trap should be handled in hyp. */
KVM_NVHE_ALIAS(vgic_v2_cpuif_trap);
KVM_NVHE_ALIAS(vgic_v3_cpuif_trap);
/* Static key checked in pmr_sync(). */
#ifdef CONFIG_ARM64_PSEUDO_NMI
KVM_NVHE_ALIAS(gic_pmr_sync);
#endif
/* EL2 exception handling */
KVM_NVHE_ALIAS(__start___kvm_ex_table);
KVM_NVHE_ALIAS(__stop___kvm_ex_table);
#endif /* CONFIG_KVM */
#endif /* __ARM64_KERNEL_IMAGE_VARS_H */