#ifndef __ARM64_HYP_IMAGE_H__
#define __ARM64_HYP_IMAGE_H__
+#define __HYP_CONCAT(a, b) a ## b
+#define HYP_CONCAT(a, b) __HYP_CONCAT(a, b)
+
/*
* KVM nVHE code has its own symbol namespace prefixed with __kvm_nvhe_,
* to separate it from the kernel proper.
*/
#define HYP_SECTION_NAME(NAME) .hyp##NAME
+/* Symbol defined at the beginning of each hyp section. */
+#define HYP_SECTION_SYMBOL_NAME(NAME) \
+ HYP_CONCAT(__hyp_section_, HYP_SECTION_NAME(NAME))
+
+/*
+ * Helper to generate linker script statements starting a hyp section.
+ *
+ * A symbol with a well-known name is defined at the first byte. This
+ * is used as a base for hyp relocations (see gen-hyprel.c). It must
+ * be defined inside the section so the linker of `vmlinux` cannot
+ * separate it from the section data.
+ */
+#define BEGIN_HYP_SECTION(NAME) \
+ HYP_SECTION_NAME(NAME) : { \
+ HYP_SECTION_SYMBOL_NAME(NAME) = .;
+
+/* Helper to generate linker script statements ending a hyp section. */
+#define END_HYP_SECTION \
+ }
+
/* Defines an ELF hyp section from input section @NAME and its subsections. */
-#define HYP_SECTION(NAME) \
- HYP_SECTION_NAME(NAME) : { *(NAME NAME##.*) }
+#define HYP_SECTION(NAME) \
+ BEGIN_HYP_SECTION(NAME) \
+ *(NAME NAME##.*) \
+ END_HYP_SECTION
/*
* Defines a linker script alias of a kernel-proper symbol referenced by
extern u32 __kvm_get_mdcr_el2(void);
-/*
- * Obtain the PC-relative address of a kernel symbol
- * s: symbol
- *
- * The goal of this macro is to return a symbol's address based on a
- * PC-relative computation, as opposed to a loading the VA from a
- * constant pool or something similar. This works well for HYP, as an
- * absolute VA is guaranteed to be wrong. Only use this if trying to
- * obtain the address of a symbol (i.e. not something you obtained by
- * following a pointer).
- */
-#define hyp_symbol_addr(s) \
- ({ \
- typeof(s) *addr; \
- asm("adrp %0, %1\n" \
- "add %0, %0, :lo12:%1\n" \
- : "=r" (addr) : "S" (&s)); \
- addr; \
- })
-
#define __KVM_EXTABLE(from, to) \
" .pushsection __kvm_ex_table, \"a\"\n" \
" .align 3\n" \
.endm
/*
- * Convert a kernel image address to a PA
- * reg: kernel address to be converted in place
+ * Convert a hypervisor VA to a PA
+ * reg: hypervisor address to be converted in place
* tmp: temporary register
- *
- * The actual code generation takes place in kvm_get_kimage_voffset, and
- * the instructions below are only there to reserve the space and
- * perform the register allocation (kvm_get_kimage_voffset uses the
- * specific registers encoded in the instructions).
*/
-.macro kimg_pa reg, tmp
-alternative_cb kvm_get_kimage_voffset
- movz \tmp, #0
- movk \tmp, #0, lsl #16
- movk \tmp, #0, lsl #32
- movk \tmp, #0, lsl #48
-alternative_cb_end
-
- /* reg = __pa(reg) */
- sub \reg, \reg, \tmp
+.macro hyp_pa reg, tmp
+ ldr_l \tmp, hyp_physvirt_offset
+ add \reg, \reg, \tmp
.endm
/*
- * Convert a kernel image address to a hyp VA
- * reg: kernel address to be converted in place
+ * Convert a hypervisor VA to a kernel image address
+ * reg: hypervisor address to be converted in place
* tmp: temporary register
*
* The actual code generation takes place in kvm_get_kimage_voffset, and
* the instructions below are only there to reserve the space and
- * perform the register allocation (kvm_update_kimg_phys_offset uses the
+ * perform the register allocation (kvm_get_kimage_voffset uses the
* specific registers encoded in the instructions).
*/
-.macro kimg_hyp_va reg, tmp
-alternative_cb kvm_update_kimg_phys_offset
+.macro hyp_kimg_va reg, tmp
+ /* Convert hyp VA -> PA. */
+ hyp_pa \reg, \tmp
+
+ /* Load kimage_voffset. */
+alternative_cb kvm_get_kimage_voffset
movz \tmp, #0
movk \tmp, #0, lsl #16
movk \tmp, #0, lsl #32
movk \tmp, #0, lsl #48
alternative_cb_end
- sub \reg, \reg, \tmp
- mov_q \tmp, PAGE_OFFSET
- orr \reg, \reg, \tmp
- kern_hyp_va \reg
+ /* Convert PA -> kimg VA. */
+ add \reg, \reg, \tmp
.endm
#else
void kvm_update_va_mask(struct alt_instr *alt,
__le32 *origptr, __le32 *updptr, int nr_inst);
void kvm_compute_layout(void);
+void kvm_apply_hyp_relocations(void);
static __always_inline unsigned long __kern_hyp_va(unsigned long v)
{
#define kern_hyp_va(v) ((typeof(v))(__kern_hyp_va((unsigned long)(v))))
-static __always_inline unsigned long __kimg_hyp_va(unsigned long v)
-{
- unsigned long offset;
-
- asm volatile(ALTERNATIVE_CB("movz %0, #0\n"
- "movk %0, #0, lsl #16\n"
- "movk %0, #0, lsl #32\n"
- "movk %0, #0, lsl #48\n",
- kvm_update_kimg_phys_offset)
- : "=r" (offset));
-
- return __kern_hyp_va((v - offset) | PAGE_OFFSET);
-}
-
-#define kimg_fn_hyp_va(v) ((typeof(*v))(__kimg_hyp_va((unsigned long)(v))))
-
-#define kimg_fn_ptr(x) (typeof(x) **)(x)
-
/*
* We currently support using a VM-specified IPA size. For backward
* compatibility, the default IPA size is fixed to 40bits.
extern char __hibernate_exit_text_start[], __hibernate_exit_text_end[];
extern char __hyp_idmap_text_start[], __hyp_idmap_text_end[];
extern char __hyp_text_start[], __hyp_text_end[];
-extern char __hyp_data_ro_after_init_start[], __hyp_data_ro_after_init_end[];
+extern char __hyp_rodata_start[], __hyp_rodata_end[];
+extern char __hyp_reloc_begin[], __hyp_reloc_end[];
extern char __idmap_text_start[], __idmap_text_end[];
extern char __initdata_begin[], __initdata_end[];
extern char __inittext_begin[], __inittext_end[];
/* Alternative callbacks for init-time patching of nVHE hyp code. */
KVM_NVHE_ALIAS(kvm_patch_vector_branch);
KVM_NVHE_ALIAS(kvm_update_va_mask);
-KVM_NVHE_ALIAS(kvm_update_kimg_phys_offset);
KVM_NVHE_ALIAS(kvm_get_kimage_voffset);
/* Global kernel state accessed by nVHE hyp code. */
"CPU: CPUs started in inconsistent modes");
else
pr_info("CPU: All CPU(s) started at EL1\n");
- if (IS_ENABLED(CONFIG_KVM) && !is_kernel_in_hyp_mode())
+ if (IS_ENABLED(CONFIG_KVM) && !is_kernel_in_hyp_mode()) {
kvm_compute_layout();
+ kvm_apply_hyp_relocations();
+ }
}
void __init smp_cpus_done(unsigned int max_cpus)
__stop___kvm_ex_table = .;
#define HYPERVISOR_DATA_SECTIONS \
- HYP_SECTION_NAME(.data..ro_after_init) : { \
- __hyp_data_ro_after_init_start = .; \
+ HYP_SECTION_NAME(.rodata) : { \
+ __hyp_rodata_start = .; \
*(HYP_SECTION_NAME(.data..ro_after_init)) \
- __hyp_data_ro_after_init_end = .; \
+ *(HYP_SECTION_NAME(.rodata)) \
+ __hyp_rodata_end = .; \
}
#define HYPERVISOR_PERCPU_SECTION \
HYP_SECTION_NAME(.data..percpu) : { \
*(HYP_SECTION_NAME(.data..percpu)) \
}
+
+#define HYPERVISOR_RELOC_SECTION \
+ .hyp.reloc : ALIGN(4) { \
+ __hyp_reloc_begin = .; \
+ *(.hyp.reloc) \
+ __hyp_reloc_end = .; \
+ }
+
#else /* CONFIG_KVM */
#define HYPERVISOR_EXTABLE
#define HYPERVISOR_DATA_SECTIONS
#define HYPERVISOR_PERCPU_SECTION
+#define HYPERVISOR_RELOC_SECTION
#endif
#define HYPERVISOR_TEXT \
PERCPU_SECTION(L1_CACHE_BYTES)
HYPERVISOR_PERCPU_SECTION
+ HYPERVISOR_RELOC_SECTION
+
.rela.dyn : ALIGN(8) {
*(.rela .rela*)
}
goto out_err;
}
- err = create_hyp_mappings(kvm_ksym_ref(__hyp_data_ro_after_init_start),
- kvm_ksym_ref(__hyp_data_ro_after_init_end),
- PAGE_HYP_RO);
+ err = create_hyp_mappings(kvm_ksym_ref(__hyp_rodata_start),
+ kvm_ksym_ref(__hyp_rodata_end), PAGE_HYP_RO);
if (err) {
- kvm_err("Cannot map .hyp.data..ro_after_init section\n");
+ kvm_err("Cannot map .hyp.rodata section\n");
goto out_err;
}
struct exception_table_entry *entry, *end;
unsigned long elr_el2 = read_sysreg(elr_el2);
- entry = hyp_symbol_addr(__start___kvm_ex_table);
- end = hyp_symbol_addr(__stop___kvm_ex_table);
+ entry = &__start___kvm_ex_table;
+ end = &__stop___kvm_ex_table;
while (entry < end) {
addr = (unsigned long)&entry->insn + entry->insn;
# SPDX-License-Identifier: GPL-2.0-only
+gen-hyprel
hyp.lds
+hyp-reloc.S
asflags-y := -D__KVM_NVHE_HYPERVISOR__
ccflags-y := -D__KVM_NVHE_HYPERVISOR__
+hostprogs := gen-hyprel
+
obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o \
hyp-main.o hyp-smp.o psci-relay.o
obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \
hyp-obj := $(patsubst %.o,%.nvhe.o,$(obj-y))
obj-y := kvm_nvhe.o
-extra-y := $(hyp-obj) kvm_nvhe.tmp.o hyp.lds
+extra-y := $(hyp-obj) kvm_nvhe.tmp.o kvm_nvhe.rel.o hyp.lds hyp-reloc.S hyp-reloc.o
# 1) Compile all source files to `.nvhe.o` object files. The file extension
# avoids file name clashes for files shared with VHE.
$(obj)/kvm_nvhe.tmp.o: $(obj)/hyp.lds $(addprefix $(obj)/,$(hyp-obj)) FORCE
$(call if_changed,ld)
-# 4) Produce the final 'kvm_nvhe.o', ready to be linked into 'vmlinux'.
+# 4) Generate list of hyp code/data positions that need to be relocated at
+# runtime. Because the hypervisor is part of the kernel binary, relocations
+# produce a kernel VA. We enumerate relocations targeting hyp at build time
+# and convert the kernel VAs at those positions to hyp VAs.
+$(obj)/hyp-reloc.S: $(obj)/kvm_nvhe.tmp.o $(obj)/gen-hyprel
+ $(call if_changed,hyprel)
+
+# 5) Compile hyp-reloc.S and link it into the existing partially linked object.
+# The object file now contains a section with pointers to hyp positions that
+# will contain kernel VAs at runtime. These pointers have relocations on them
+# so that they get updated as the hyp object is linked into `vmlinux`.
+LDFLAGS_kvm_nvhe.rel.o := -r
+$(obj)/kvm_nvhe.rel.o: $(obj)/kvm_nvhe.tmp.o $(obj)/hyp-reloc.o FORCE
+ $(call if_changed,ld)
+
+# 6) Produce the final 'kvm_nvhe.o', ready to be linked into 'vmlinux'.
# Prefixes names of ELF symbols with '__kvm_nvhe_'.
-$(obj)/kvm_nvhe.o: $(obj)/kvm_nvhe.tmp.o FORCE
+$(obj)/kvm_nvhe.o: $(obj)/kvm_nvhe.rel.o FORCE
$(call if_changed,hypcopy)
+# The HYPREL command calls `gen-hyprel` to generate an assembly file with
+# a list of relocations targeting hyp code/data.
+quiet_cmd_hyprel = HYPREL $@
+ cmd_hyprel = $(obj)/gen-hyprel $< > $@
+
# The HYPCOPY command uses `objcopy` to prefix all ELF symbol names
# to avoid clashes with VHE code/data.
quiet_cmd_hypcopy = HYPCOPY $@
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 - Google LLC
+ * Author: David Brazdil <dbrazdil@google.com>
+ *
+ * Generates relocation information used by the kernel to convert
+ * absolute addresses in hyp data from kernel VAs to hyp VAs.
+ *
+ * This is necessary because hyp code is linked into the same binary
+ * as the kernel but executes under different memory mappings.
+ * If the compiler used absolute addressing, those addresses need to
+ * be converted before they are used by hyp code.
+ *
+ * The input of this program is the relocatable ELF object containing
+ * all hyp code/data, not yet linked into vmlinux. Hyp section names
+ * should have been prefixed with `.hyp` at this point.
+ *
+ * The output (printed to stdout) is an assembly file containing
+ * an array of 32-bit integers and static relocations that instruct
+ * the linker of `vmlinux` to populate the array entries with offsets
+ * to positions in the kernel binary containing VAs used by hyp code.
+ *
+ * Note that dynamic relocations could be used for the same purpose.
+ * However, those are only generated if CONFIG_RELOCATABLE=y.
+ */
+
+#include <elf.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#define HYP_SECTION_PREFIX ".hyp"
+#define HYP_RELOC_SECTION ".hyp.reloc"
+#define HYP_SECTION_SYMBOL_PREFIX "__hyp_section_"
+
+/*
+ * AArch64 relocation type constants.
+ * Included in case these are not defined in the host toolchain.
+ */
+#ifndef R_AARCH64_ABS64
+#define R_AARCH64_ABS64 257
+#endif
+#ifndef R_AARCH64_LD_PREL_LO19
+#define R_AARCH64_LD_PREL_LO19 273
+#endif
+#ifndef R_AARCH64_ADR_PREL_LO21
+#define R_AARCH64_ADR_PREL_LO21 274
+#endif
+#ifndef R_AARCH64_ADR_PREL_PG_HI21
+#define R_AARCH64_ADR_PREL_PG_HI21 275
+#endif
+#ifndef R_AARCH64_ADR_PREL_PG_HI21_NC
+#define R_AARCH64_ADR_PREL_PG_HI21_NC 276
+#endif
+#ifndef R_AARCH64_ADD_ABS_LO12_NC
+#define R_AARCH64_ADD_ABS_LO12_NC 277
+#endif
+#ifndef R_AARCH64_LDST8_ABS_LO12_NC
+#define R_AARCH64_LDST8_ABS_LO12_NC 278
+#endif
+#ifndef R_AARCH64_TSTBR14
+#define R_AARCH64_TSTBR14 279
+#endif
+#ifndef R_AARCH64_CONDBR19
+#define R_AARCH64_CONDBR19 280
+#endif
+#ifndef R_AARCH64_JUMP26
+#define R_AARCH64_JUMP26 282
+#endif
+#ifndef R_AARCH64_CALL26
+#define R_AARCH64_CALL26 283
+#endif
+#ifndef R_AARCH64_LDST16_ABS_LO12_NC
+#define R_AARCH64_LDST16_ABS_LO12_NC 284
+#endif
+#ifndef R_AARCH64_LDST32_ABS_LO12_NC
+#define R_AARCH64_LDST32_ABS_LO12_NC 285
+#endif
+#ifndef R_AARCH64_LDST64_ABS_LO12_NC
+#define R_AARCH64_LDST64_ABS_LO12_NC 286
+#endif
+#ifndef R_AARCH64_MOVW_PREL_G0
+#define R_AARCH64_MOVW_PREL_G0 287
+#endif
+#ifndef R_AARCH64_MOVW_PREL_G0_NC
+#define R_AARCH64_MOVW_PREL_G0_NC 288
+#endif
+#ifndef R_AARCH64_MOVW_PREL_G1
+#define R_AARCH64_MOVW_PREL_G1 289
+#endif
+#ifndef R_AARCH64_MOVW_PREL_G1_NC
+#define R_AARCH64_MOVW_PREL_G1_NC 290
+#endif
+#ifndef R_AARCH64_MOVW_PREL_G2
+#define R_AARCH64_MOVW_PREL_G2 291
+#endif
+#ifndef R_AARCH64_MOVW_PREL_G2_NC
+#define R_AARCH64_MOVW_PREL_G2_NC 292
+#endif
+#ifndef R_AARCH64_MOVW_PREL_G3
+#define R_AARCH64_MOVW_PREL_G3 293
+#endif
+#ifndef R_AARCH64_LDST128_ABS_LO12_NC
+#define R_AARCH64_LDST128_ABS_LO12_NC 299
+#endif
+
+/* Global state of the processed ELF. */
+static struct {
+ const char *path;
+ char *begin;
+ size_t size;
+ Elf64_Ehdr *ehdr;
+ Elf64_Shdr *sh_table;
+ const char *sh_string;
+} elf;
+
+#define fatal_error(fmt, ...) \
+ ({ \
+ fprintf(stderr, "error: %s: " fmt "\n", \
+ elf.path, ## __VA_ARGS__); \
+ exit(EXIT_FAILURE); \
+ __builtin_unreachable(); \
+ })
+
+#define fatal_perror(msg) \
+ ({ \
+ fprintf(stderr, "error: %s: " msg ": %s\n", \
+ elf.path, strerror(errno)); \
+ exit(EXIT_FAILURE); \
+ __builtin_unreachable(); \
+ })
+
+#define assert_op(lhs, rhs, fmt, op) \
+ ({ \
+ typeof(lhs) _lhs = (lhs); \
+ typeof(rhs) _rhs = (rhs); \
+ \
+ if (!(_lhs op _rhs)) { \
+ fatal_error("assertion " #lhs " " #op " " #rhs \
+ " failed (lhs=" fmt ", rhs=" fmt \
+ ", line=%d)", _lhs, _rhs, __LINE__); \
+ } \
+ })
+
+#define assert_eq(lhs, rhs, fmt) assert_op(lhs, rhs, fmt, ==)
+#define assert_ne(lhs, rhs, fmt) assert_op(lhs, rhs, fmt, !=)
+#define assert_lt(lhs, rhs, fmt) assert_op(lhs, rhs, fmt, <)
+#define assert_ge(lhs, rhs, fmt) assert_op(lhs, rhs, fmt, >=)
+
+/*
+ * Return a pointer of a given type at a given offset from
+ * the beginning of the ELF file.
+ */
+#define elf_ptr(type, off) ((type *)(elf.begin + (off)))
+
+/* Iterate over all sections in the ELF. */
+#define for_each_section(var) \
+ for (var = elf.sh_table; var < elf.sh_table + elf.ehdr->e_shnum; ++var)
+
+/* Iterate over all Elf64_Rela relocations in a given section. */
+#define for_each_rela(shdr, var) \
+ for (var = elf_ptr(Elf64_Rela, shdr->sh_offset); \
+ var < elf_ptr(Elf64_Rela, shdr->sh_offset + shdr->sh_size); var++)
+
+/* True if a string starts with a given prefix. */
+static inline bool starts_with(const char *str, const char *prefix)
+{
+ return memcmp(str, prefix, strlen(prefix)) == 0;
+}
+
+/* Returns a string containing the name of a given section. */
+static inline const char *section_name(Elf64_Shdr *shdr)
+{
+ return elf.sh_string + shdr->sh_name;
+}
+
+/* Returns a pointer to the first byte of section data. */
+static inline const char *section_begin(Elf64_Shdr *shdr)
+{
+ return elf_ptr(char, shdr->sh_offset);
+}
+
+/* Find a section by its offset from the beginning of the file. */
+static inline Elf64_Shdr *section_by_off(Elf64_Off off)
+{
+ assert_ne(off, 0UL, "%lu");
+ return elf_ptr(Elf64_Shdr, off);
+}
+
+/* Find a section by its index. */
+static inline Elf64_Shdr *section_by_idx(uint16_t idx)
+{
+ assert_ne(idx, SHN_UNDEF, "%u");
+ return &elf.sh_table[idx];
+}
+
+/*
+ * Memory-map the given ELF file, perform sanity checks, and
+ * populate global state.
+ */
+static void init_elf(const char *path)
+{
+ int fd, ret;
+ struct stat stat;
+
+ /* Store path in the global struct for error printing. */
+ elf.path = path;
+
+ /* Open the ELF file. */
+ fd = open(path, O_RDONLY);
+ if (fd < 0)
+ fatal_perror("Could not open ELF file");
+
+ /* Get status of ELF file to obtain its size. */
+ ret = fstat(fd, &stat);
+ if (ret < 0) {
+ close(fd);
+ fatal_perror("Could not get status of ELF file");
+ }
+
+ /* mmap() the entire ELF file read-only at an arbitrary address. */
+ elf.begin = mmap(0, stat.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+ if (elf.begin == MAP_FAILED) {
+ close(fd);
+ fatal_perror("Could not mmap ELF file");
+ }
+
+ /* mmap() was successful, close the FD. */
+ close(fd);
+
+ /* Get pointer to the ELF header. */
+ assert_ge(stat.st_size, sizeof(*elf.ehdr), "%lu");
+ elf.ehdr = elf_ptr(Elf64_Ehdr, 0);
+
+ /* Check the ELF magic. */
+ assert_eq(elf.ehdr->e_ident[EI_MAG0], ELFMAG0, "0x%x");
+ assert_eq(elf.ehdr->e_ident[EI_MAG1], ELFMAG1, "0x%x");
+ assert_eq(elf.ehdr->e_ident[EI_MAG2], ELFMAG2, "0x%x");
+ assert_eq(elf.ehdr->e_ident[EI_MAG3], ELFMAG3, "0x%x");
+
+ /* Sanity check that this is an ELF64 relocatable object for AArch64. */
+ assert_eq(elf.ehdr->e_ident[EI_CLASS], ELFCLASS64, "%u");
+ assert_eq(elf.ehdr->e_ident[EI_DATA], ELFDATA2LSB, "%u");
+ assert_eq(elf.ehdr->e_type, ET_REL, "%u");
+ assert_eq(elf.ehdr->e_machine, EM_AARCH64, "%u");
+
+ /* Populate fields of the global struct. */
+ elf.sh_table = section_by_off(elf.ehdr->e_shoff);
+ elf.sh_string = section_begin(section_by_idx(elf.ehdr->e_shstrndx));
+}
+
+/* Print the prologue of the output ASM file. */
+static void emit_prologue(void)
+{
+ printf(".data\n"
+ ".pushsection " HYP_RELOC_SECTION ", \"a\"\n");
+}
+
+/* Print ASM statements needed as a prologue to a processed hyp section. */
+static void emit_section_prologue(const char *sh_orig_name)
+{
+ /* Declare the hyp section symbol. */
+ printf(".global %s%s\n", HYP_SECTION_SYMBOL_PREFIX, sh_orig_name);
+}
+
+/*
+ * Print ASM statements to create a hyp relocation entry for a given
+ * R_AARCH64_ABS64 relocation.
+ *
+ * The linker of vmlinux will populate the position given by `rela` with
+ * an absolute 64-bit kernel VA. If the kernel is relocatable, it will
+ * also generate a dynamic relocation entry so that the kernel can shift
+ * the address at runtime for KASLR.
+ *
+ * Emit a 32-bit offset from the current address to the position given
+ * by `rela`. This way the kernel can iterate over all kernel VAs used
+ * by hyp at runtime and convert them to hyp VAs. However, that offset
+ * will not be known until linking of `vmlinux`, so emit a PREL32
+ * relocation referencing a symbol that the hyp linker script put at
+ * the beginning of the relocated section + the offset from `rela`.
+ */
+static void emit_rela_abs64(Elf64_Rela *rela, const char *sh_orig_name)
+{
+ /* Offset of this reloc from the beginning of HYP_RELOC_SECTION. */
+ static size_t reloc_offset;
+
+ /* Create storage for the 32-bit offset. */
+ printf(".word 0\n");
+
+ /*
+ * Create a PREL32 relocation which instructs the linker of `vmlinux`
+ * to insert offset to position <base> + <offset>, where <base> is
+ * a symbol at the beginning of the relocated section, and <offset>
+ * is `rela->r_offset`.
+ */
+ printf(".reloc %lu, R_AARCH64_PREL32, %s%s + 0x%lx\n",
+ reloc_offset, HYP_SECTION_SYMBOL_PREFIX, sh_orig_name,
+ rela->r_offset);
+
+ reloc_offset += 4;
+}
+
+/* Print the epilogue of the output ASM file. */
+static void emit_epilogue(void)
+{
+ printf(".popsection\n");
+}
+
+/*
+ * Iterate over all RELA relocations in a given section and emit
+ * hyp relocation data for all absolute addresses in hyp code/data.
+ *
+ * Static relocations that generate PC-relative-addressing are ignored.
+ * Failure is reported for unexpected relocation types.
+ */
+static void emit_rela_section(Elf64_Shdr *sh_rela)
+{
+ Elf64_Shdr *sh_orig = &elf.sh_table[sh_rela->sh_info];
+ const char *sh_orig_name = section_name(sh_orig);
+ Elf64_Rela *rela;
+
+ /* Skip all non-hyp sections. */
+ if (!starts_with(sh_orig_name, HYP_SECTION_PREFIX))
+ return;
+
+ emit_section_prologue(sh_orig_name);
+
+ for_each_rela(sh_rela, rela) {
+ uint32_t type = (uint32_t)rela->r_info;
+
+ /* Check that rela points inside the relocated section. */
+ assert_lt(rela->r_offset, sh_orig->sh_size, "0x%lx");
+
+ switch (type) {
+ /*
+ * Data relocations to generate absolute addressing.
+ * Emit a hyp relocation.
+ */
+ case R_AARCH64_ABS64:
+ emit_rela_abs64(rela, sh_orig_name);
+ break;
+ /* Allow relocations to generate PC-relative addressing. */
+ case R_AARCH64_LD_PREL_LO19:
+ case R_AARCH64_ADR_PREL_LO21:
+ case R_AARCH64_ADR_PREL_PG_HI21:
+ case R_AARCH64_ADR_PREL_PG_HI21_NC:
+ case R_AARCH64_ADD_ABS_LO12_NC:
+ case R_AARCH64_LDST8_ABS_LO12_NC:
+ case R_AARCH64_LDST16_ABS_LO12_NC:
+ case R_AARCH64_LDST32_ABS_LO12_NC:
+ case R_AARCH64_LDST64_ABS_LO12_NC:
+ case R_AARCH64_LDST128_ABS_LO12_NC:
+ break;
+ /* Allow relative relocations for control-flow instructions. */
+ case R_AARCH64_TSTBR14:
+ case R_AARCH64_CONDBR19:
+ case R_AARCH64_JUMP26:
+ case R_AARCH64_CALL26:
+ break;
+ /* Allow group relocations to create PC-relative offset inline. */
+ case R_AARCH64_MOVW_PREL_G0:
+ case R_AARCH64_MOVW_PREL_G0_NC:
+ case R_AARCH64_MOVW_PREL_G1:
+ case R_AARCH64_MOVW_PREL_G1_NC:
+ case R_AARCH64_MOVW_PREL_G2:
+ case R_AARCH64_MOVW_PREL_G2_NC:
+ case R_AARCH64_MOVW_PREL_G3:
+ break;
+ default:
+ fatal_error("Unexpected RELA type %u", type);
+ }
+ }
+}
+
+/* Iterate over all sections and emit hyp relocation data for RELA sections. */
+static void emit_all_relocs(void)
+{
+ Elf64_Shdr *shdr;
+
+ for_each_section(shdr) {
+ switch (shdr->sh_type) {
+ case SHT_REL:
+ fatal_error("Unexpected SHT_REL section \"%s\"",
+ section_name(shdr));
+ case SHT_RELA:
+ emit_rela_section(shdr);
+ break;
+ }
+ }
+}
+
+int main(int argc, const char **argv)
+{
+ if (argc != 2) {
+ fprintf(stderr, "Usage: %s <elf_input>\n", argv[0]);
+ return EXIT_FAILURE;
+ }
+
+ init_elf(argv[1]);
+
+ emit_prologue();
+ emit_all_relocs();
+ emit_epilogue();
+
+ return EXIT_SUCCESS;
+}
* void __noreturn __hyp_do_panic(bool restore_host, u64 spsr, u64 elr, u64 par);
*/
SYM_FUNC_START(__hyp_do_panic)
- /* Load the format arguments into x1-7 */
- 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
+ hyp_kimg_va lr, x6
msr elr_el2, lr
- /*
- * Set the panic format string and enter the host, conditionally
- * restoring the host context.
- */
+ /* Set the panic format string. Use the, now free, LR as scratch. */
+ ldr lr, =__hyp_panic_string
+ hyp_kimg_va lr, x6
+
+ /* Load the format arguments into x1-7. */
+ mov x6, x3
+ get_vcpu_ptr x7, x3
+ mrs x3, esr_el2
+ mrs x4, far_el2
+ mrs x5, hpfar_el2
+
+ /* Enter the host, conditionally restoring the host context. */
cmp x0, xzr
- ldr x0, =__hyp_panic_string
+ mov x0, lr
b.eq __host_enter_without_restoring
b __host_enter_for_panic
SYM_FUNC_END(__hyp_do_panic)
* Preserve x0-x4, which may contain stub parameters.
*/
ldr x5, =__kvm_handle_stub_hvc
- kimg_pa x5, x6
+ hyp_pa x5, x6
br x5
.L__vect_end\@:
.if ((.L__vect_end\@ - .L__vect_start\@) > 0x80)
#include <asm/virt.h>
.text
- .pushsection .hyp.idmap.text, "ax"
+ .pushsection .idmap.text, "ax"
.align 11
/* Set the host vector */
ldr x0, =__kvm_hyp_host_vector
- kimg_hyp_va x0, x1
msr vbar_el2, x0
ret
/* Leave idmap. */
mov x0, x29
ldr x1, =kvm_host_psci_cpu_entry
- kimg_hyp_va x1, x2
br x1
SYM_CODE_END(__kvm_hyp_init_cpu)
typedef void (*hcall_t)(struct kvm_cpu_context *);
-#define HANDLE_FUNC(x) [__KVM_HOST_SMCCC_FUNC_##x] = kimg_fn_ptr(handle_##x)
+#define HANDLE_FUNC(x) [__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x
-static const hcall_t *host_hcall[] = {
+static const hcall_t host_hcall[] = {
HANDLE_FUNC(__kvm_vcpu_run),
HANDLE_FUNC(__kvm_flush_vm_context),
HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa),
static void handle_host_hcall(struct kvm_cpu_context *host_ctxt)
{
DECLARE_REG(unsigned long, id, host_ctxt, 0);
- const hcall_t *kfn;
hcall_t hfn;
id -= KVM_HOST_SMCCC_ID(0);
if (unlikely(id >= ARRAY_SIZE(host_hcall)))
goto inval;
- kfn = host_hcall[id];
- if (unlikely(!kfn))
+ hfn = host_hcall[id];
+ if (unlikely(!hfn))
goto inval;
cpu_reg(host_ctxt, 0) = SMCCC_RET_SUCCESS;
-
- hfn = kimg_fn_hyp_va(kfn);
hfn(host_ctxt);
return;
if (cpu >= ARRAY_SIZE(kvm_arm_hyp_percpu_base))
hyp_panic();
- cpu_base_array = (unsigned long *)hyp_symbol_addr(kvm_arm_hyp_percpu_base);
+ cpu_base_array = (unsigned long *)&kvm_arm_hyp_percpu_base;
this_cpu_base = kern_hyp_va(cpu_base_array[cpu]);
- elf_base = (unsigned long)hyp_symbol_addr(__per_cpu_start);
+ elf_base = (unsigned long)&__per_cpu_start;
return this_cpu_base - elf_base;
}
#include <asm/memory.h>
SECTIONS {
+ HYP_SECTION(.idmap.text)
HYP_SECTION(.text)
+ HYP_SECTION(.data..ro_after_init)
+ HYP_SECTION(.rodata)
+
/*
* .hyp..data..percpu needs to be page aligned to maintain the same
* alignment for when linking into vmlinux.
*/
. = ALIGN(PAGE_SIZE);
- HYP_SECTION_NAME(.data..percpu) : {
+ BEGIN_HYP_SECTION(.data..percpu)
PERCPU_INPUT(L1_CACHE_BYTES)
- }
- HYP_SECTION(.data..ro_after_init)
+ END_HYP_SECTION
}
if (cpu_id == INVALID_CPU_ID)
return PSCI_RET_INVALID_PARAMS;
- boot_args = per_cpu_ptr(hyp_symbol_addr(cpu_on_args), cpu_id);
- init_params = per_cpu_ptr(hyp_symbol_addr(kvm_init_params), cpu_id);
+ boot_args = per_cpu_ptr(&cpu_on_args, cpu_id);
+ init_params = per_cpu_ptr(&kvm_init_params, cpu_id);
/* Check if the target CPU is already being booted. */
if (!try_acquire_boot_args(boot_args))
wmb();
ret = psci_call(func_id, mpidr,
- __hyp_pa(hyp_symbol_addr(kvm_hyp_cpu_entry)),
+ __hyp_pa(&kvm_hyp_cpu_entry),
__hyp_pa(init_params));
/* If successful, the lock will be released by the target CPU. */
struct psci_boot_args *boot_args;
struct kvm_nvhe_init_params *init_params;
- boot_args = this_cpu_ptr(hyp_symbol_addr(suspend_args));
- init_params = this_cpu_ptr(hyp_symbol_addr(kvm_init_params));
+ boot_args = this_cpu_ptr(&suspend_args);
+ init_params = this_cpu_ptr(&kvm_init_params);
/*
* No need to acquire a lock before writing to boot_args because a core
* point if it is a deep sleep state.
*/
return psci_call(func_id, power_state,
- __hyp_pa(hyp_symbol_addr(kvm_hyp_cpu_resume)),
+ __hyp_pa(&kvm_hyp_cpu_resume),
__hyp_pa(init_params));
}
struct psci_boot_args *boot_args;
struct kvm_nvhe_init_params *init_params;
- boot_args = this_cpu_ptr(hyp_symbol_addr(suspend_args));
- init_params = this_cpu_ptr(hyp_symbol_addr(kvm_init_params));
+ boot_args = this_cpu_ptr(&suspend_args);
+ init_params = this_cpu_ptr(&kvm_init_params);
/*
* No need to acquire a lock before writing to boot_args because a core
/* Will only return on error. */
return psci_call(func_id,
- __hyp_pa(hyp_symbol_addr(kvm_hyp_cpu_resume)),
+ __hyp_pa(&kvm_hyp_cpu_resume),
__hyp_pa(init_params), 0);
}
struct psci_boot_args *boot_args;
struct kvm_cpu_context *host_ctxt;
- host_ctxt = &this_cpu_ptr(hyp_symbol_addr(kvm_host_data))->host_ctxt;
+ host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt;
if (is_cpu_on)
- boot_args = this_cpu_ptr(hyp_symbol_addr(cpu_on_args));
+ boot_args = this_cpu_ptr(&cpu_on_args);
else
- boot_args = this_cpu_ptr(hyp_symbol_addr(suspend_args));
+ boot_args = this_cpu_ptr(&suspend_args);
cpu_reg(host_ctxt, 0) = boot_args->r0;
write_sysreg_el2(boot_args->pc, SYS_ELR);
}
rd = kvm_vcpu_dabt_get_rd(vcpu);
- addr = hyp_symbol_addr(kvm_vgic_global_state)->vcpu_hyp_va;
+ addr = kvm_vgic_global_state.vcpu_hyp_va;
addr += fault_ipa - vgic->vgic_cpu_base;
if (kvm_vcpu_dabt_iswrite(vcpu)) {
init_hyp_physvirt_offset();
}
+/*
+ * The .hyp.reloc ELF section contains a list of kimg positions that
+ * contains kimg VAs but will be accessed only in hyp execution context.
+ * Convert them to hyp VAs. See gen-hyprel.c for more details.
+ */
+__init void kvm_apply_hyp_relocations(void)
+{
+ int32_t *rel;
+ int32_t *begin = (int32_t *)__hyp_reloc_begin;
+ int32_t *end = (int32_t *)__hyp_reloc_end;
+
+ for (rel = begin; rel < end; ++rel) {
+ uintptr_t *ptr, kimg_va;
+
+ /*
+ * Each entry contains a 32-bit relative offset from itself
+ * to a kimg VA position.
+ */
+ ptr = (uintptr_t *)lm_alias((char *)rel + *rel);
+
+ /* Read the kimg VA value at the relocation address. */
+ kimg_va = *ptr;
+
+ /* Convert to hyp VA and store back to the relocation address. */
+ *ptr = __early_kern_hyp_va((uintptr_t)lm_alias(kimg_va));
+ }
+}
+
static u32 compute_instruction(int n, u32 rd, u32 rn)
{
u32 insn = AARCH64_BREAK_FAULT;
*updptr++ = cpu_to_le32(insn);
}
-void kvm_update_kimg_phys_offset(struct alt_instr *alt,
- __le32 *origptr, __le32 *updptr, int nr_inst)
-{
- generate_mov_q(kimage_voffset + PHYS_OFFSET, origptr, updptr, nr_inst);
-}
-
void kvm_get_kimage_voffset(struct alt_instr *alt,
__le32 *origptr, __le32 *updptr, int nr_inst)
{
projects / linux-2.6-microblaze.git / commitdiff