summaryrefslogtreecommitdiffstats
path: root/arch/arm64/kernel/vdso
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/arm64/kernel/vdso
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--arch/arm64/kernel/vdso-wrap.S24
-rw-r--r--arch/arm64/kernel/vdso.c475
-rw-r--r--arch/arm64/kernel/vdso/.gitignore2
-rw-r--r--arch/arm64/kernel/vdso/Makefile92
-rwxr-xr-xarch/arm64/kernel/vdso/gen_vdso_offsets.sh16
-rw-r--r--arch/arm64/kernel/vdso/note.S23
-rw-r--r--arch/arm64/kernel/vdso/sigreturn.S80
-rw-r--r--arch/arm64/kernel/vdso/vdso.lds.S114
-rw-r--r--arch/arm64/kernel/vdso/vgettimeofday.c25
-rw-r--r--arch/arm64/kernel/vdso32-wrap.S19
-rw-r--r--arch/arm64/kernel/vdso32/.gitignore3
-rw-r--r--arch/arm64/kernel/vdso32/Makefile189
-rw-r--r--arch/arm64/kernel/vdso32/note.c15
-rw-r--r--arch/arm64/kernel/vdso32/vdso.lds.S92
-rw-r--r--arch/arm64/kernel/vdso32/vgettimeofday.c45
15 files changed, 1214 insertions, 0 deletions
diff --git a/arch/arm64/kernel/vdso-wrap.S b/arch/arm64/kernel/vdso-wrap.S
new file mode 100644
index 000000000..c4b1990bf
--- /dev/null
+++ b/arch/arm64/kernel/vdso-wrap.S
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2012 ARM Limited
+ *
+ * Author: Will Deacon <will.deacon@arm.com>
+ */
+
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <linux/const.h>
+#include <asm/assembler.h>
+#include <asm/page.h>
+
+ .globl vdso_start, vdso_end
+ .section .rodata
+ .balign PAGE_SIZE
+vdso_start:
+ .incbin "arch/arm64/kernel/vdso/vdso.so"
+ .balign PAGE_SIZE
+vdso_end:
+
+ .previous
+
+emit_aarch64_feature_1_and
diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c
new file mode 100644
index 000000000..6ebb8dea5
--- /dev/null
+++ b/arch/arm64/kernel/vdso.c
@@ -0,0 +1,475 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * VDSO implementations.
+ *
+ * Copyright (C) 2012 ARM Limited
+ *
+ * Author: Will Deacon <will.deacon@arm.com>
+ */
+
+#include <linux/cache.h>
+#include <linux/clocksource.h>
+#include <linux/elf.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/gfp.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/signal.h>
+#include <linux/slab.h>
+#include <linux/time_namespace.h>
+#include <linux/timekeeper_internal.h>
+#include <linux/vmalloc.h>
+#include <vdso/datapage.h>
+#include <vdso/helpers.h>
+#include <vdso/vsyscall.h>
+
+#include <asm/cacheflush.h>
+#include <asm/signal32.h>
+#include <asm/vdso.h>
+
+enum vdso_abi {
+ VDSO_ABI_AA64,
+ VDSO_ABI_AA32,
+};
+
+enum vvar_pages {
+ VVAR_DATA_PAGE_OFFSET,
+ VVAR_TIMENS_PAGE_OFFSET,
+ VVAR_NR_PAGES,
+};
+
+struct vdso_abi_info {
+ const char *name;
+ const char *vdso_code_start;
+ const char *vdso_code_end;
+ unsigned long vdso_pages;
+ /* Data Mapping */
+ struct vm_special_mapping *dm;
+ /* Code Mapping */
+ struct vm_special_mapping *cm;
+};
+
+static struct vdso_abi_info vdso_info[] __ro_after_init = {
+ [VDSO_ABI_AA64] = {
+ .name = "vdso",
+ .vdso_code_start = vdso_start,
+ .vdso_code_end = vdso_end,
+ },
+#ifdef CONFIG_COMPAT_VDSO
+ [VDSO_ABI_AA32] = {
+ .name = "vdso32",
+ .vdso_code_start = vdso32_start,
+ .vdso_code_end = vdso32_end,
+ },
+#endif /* CONFIG_COMPAT_VDSO */
+};
+
+/*
+ * The vDSO data page.
+ */
+static union {
+ struct vdso_data data[CS_BASES];
+ u8 page[PAGE_SIZE];
+} vdso_data_store __page_aligned_data;
+struct vdso_data *vdso_data = vdso_data_store.data;
+
+static int vdso_mremap(const struct vm_special_mapping *sm,
+ struct vm_area_struct *new_vma)
+{
+ current->mm->context.vdso = (void *)new_vma->vm_start;
+
+ return 0;
+}
+
+static int __init __vdso_init(enum vdso_abi abi)
+{
+ int i;
+ struct page **vdso_pagelist;
+ unsigned long pfn;
+
+ if (memcmp(vdso_info[abi].vdso_code_start, "\177ELF", 4)) {
+ pr_err("vDSO is not a valid ELF object!\n");
+ return -EINVAL;
+ }
+
+ vdso_info[abi].vdso_pages = (
+ vdso_info[abi].vdso_code_end -
+ vdso_info[abi].vdso_code_start) >>
+ PAGE_SHIFT;
+
+ vdso_pagelist = kcalloc(vdso_info[abi].vdso_pages,
+ sizeof(struct page *),
+ GFP_KERNEL);
+ if (vdso_pagelist == NULL)
+ return -ENOMEM;
+
+ /* Grab the vDSO code pages. */
+ pfn = sym_to_pfn(vdso_info[abi].vdso_code_start);
+
+ for (i = 0; i < vdso_info[abi].vdso_pages; i++)
+ vdso_pagelist[i] = pfn_to_page(pfn + i);
+
+ vdso_info[abi].cm->pages = vdso_pagelist;
+
+ return 0;
+}
+
+#ifdef CONFIG_TIME_NS
+struct vdso_data *arch_get_vdso_data(void *vvar_page)
+{
+ return (struct vdso_data *)(vvar_page);
+}
+
+/*
+ * The vvar mapping contains data for a specific time namespace, so when a task
+ * changes namespace we must unmap its vvar data for the old namespace.
+ * Subsequent faults will map in data for the new namespace.
+ *
+ * For more details see timens_setup_vdso_data().
+ */
+int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
+{
+ struct mm_struct *mm = task->mm;
+ struct vm_area_struct *vma;
+ VMA_ITERATOR(vmi, mm, 0);
+
+ mmap_read_lock(mm);
+
+ for_each_vma(vmi, vma) {
+ unsigned long size = vma->vm_end - vma->vm_start;
+
+ if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_AA64].dm))
+ zap_page_range(vma, vma->vm_start, size);
+#ifdef CONFIG_COMPAT_VDSO
+ if (vma_is_special_mapping(vma, vdso_info[VDSO_ABI_AA32].dm))
+ zap_page_range(vma, vma->vm_start, size);
+#endif
+ }
+
+ mmap_read_unlock(mm);
+ return 0;
+}
+
+static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
+{
+ if (likely(vma->vm_mm == current->mm))
+ return current->nsproxy->time_ns->vvar_page;
+
+ /*
+ * VM_PFNMAP | VM_IO protect .fault() handler from being called
+ * through interfaces like /proc/$pid/mem or
+ * process_vm_{readv,writev}() as long as there's no .access()
+ * in special_mapping_vmops.
+ * For more details check_vma_flags() and __access_remote_vm()
+ */
+ WARN(1, "vvar_page accessed remotely");
+
+ return NULL;
+}
+#else
+static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
+{
+ return NULL;
+}
+#endif
+
+static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,
+ struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ struct page *timens_page = find_timens_vvar_page(vma);
+ unsigned long pfn;
+
+ switch (vmf->pgoff) {
+ case VVAR_DATA_PAGE_OFFSET:
+ if (timens_page)
+ pfn = page_to_pfn(timens_page);
+ else
+ pfn = sym_to_pfn(vdso_data);
+ break;
+#ifdef CONFIG_TIME_NS
+ case VVAR_TIMENS_PAGE_OFFSET:
+ /*
+ * If a task belongs to a time namespace then a namespace
+ * specific VVAR is mapped with the VVAR_DATA_PAGE_OFFSET and
+ * the real VVAR page is mapped with the VVAR_TIMENS_PAGE_OFFSET
+ * offset.
+ * See also the comment near timens_setup_vdso_data().
+ */
+ if (!timens_page)
+ return VM_FAULT_SIGBUS;
+ pfn = sym_to_pfn(vdso_data);
+ break;
+#endif /* CONFIG_TIME_NS */
+ default:
+ return VM_FAULT_SIGBUS;
+ }
+
+ return vmf_insert_pfn(vma, vmf->address, pfn);
+}
+
+static int __setup_additional_pages(enum vdso_abi abi,
+ struct mm_struct *mm,
+ struct linux_binprm *bprm,
+ int uses_interp)
+{
+ unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
+ unsigned long gp_flags = 0;
+ void *ret;
+
+ BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES);
+
+ vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT;
+ /* Be sure to map the data page */
+ vdso_mapping_len = vdso_text_len + VVAR_NR_PAGES * PAGE_SIZE;
+
+ vdso_base = get_unmapped_area(NULL, 0, vdso_mapping_len, 0, 0);
+ if (IS_ERR_VALUE(vdso_base)) {
+ ret = ERR_PTR(vdso_base);
+ goto up_fail;
+ }
+
+ ret = _install_special_mapping(mm, vdso_base, VVAR_NR_PAGES * PAGE_SIZE,
+ VM_READ|VM_MAYREAD|VM_PFNMAP,
+ vdso_info[abi].dm);
+ if (IS_ERR(ret))
+ goto up_fail;
+
+ if (IS_ENABLED(CONFIG_ARM64_BTI_KERNEL) && system_supports_bti())
+ gp_flags = VM_ARM64_BTI;
+
+ vdso_base += VVAR_NR_PAGES * PAGE_SIZE;
+ mm->context.vdso = (void *)vdso_base;
+ ret = _install_special_mapping(mm, vdso_base, vdso_text_len,
+ VM_READ|VM_EXEC|gp_flags|
+ VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
+ vdso_info[abi].cm);
+ if (IS_ERR(ret))
+ goto up_fail;
+
+ return 0;
+
+up_fail:
+ mm->context.vdso = NULL;
+ return PTR_ERR(ret);
+}
+
+#ifdef CONFIG_COMPAT
+/*
+ * Create and map the vectors page for AArch32 tasks.
+ */
+enum aarch32_map {
+ AA32_MAP_VECTORS, /* kuser helpers */
+ AA32_MAP_SIGPAGE,
+ AA32_MAP_VVAR,
+ AA32_MAP_VDSO,
+};
+
+static struct page *aarch32_vectors_page __ro_after_init;
+static struct page *aarch32_sig_page __ro_after_init;
+
+static int aarch32_sigpage_mremap(const struct vm_special_mapping *sm,
+ struct vm_area_struct *new_vma)
+{
+ current->mm->context.sigpage = (void *)new_vma->vm_start;
+
+ return 0;
+}
+
+static struct vm_special_mapping aarch32_vdso_maps[] = {
+ [AA32_MAP_VECTORS] = {
+ .name = "[vectors]", /* ABI */
+ .pages = &aarch32_vectors_page,
+ },
+ [AA32_MAP_SIGPAGE] = {
+ .name = "[sigpage]", /* ABI */
+ .pages = &aarch32_sig_page,
+ .mremap = aarch32_sigpage_mremap,
+ },
+ [AA32_MAP_VVAR] = {
+ .name = "[vvar]",
+ .fault = vvar_fault,
+ },
+ [AA32_MAP_VDSO] = {
+ .name = "[vdso]",
+ .mremap = vdso_mremap,
+ },
+};
+
+static int aarch32_alloc_kuser_vdso_page(void)
+{
+ extern char __kuser_helper_start[], __kuser_helper_end[];
+ int kuser_sz = __kuser_helper_end - __kuser_helper_start;
+ unsigned long vdso_page;
+
+ if (!IS_ENABLED(CONFIG_KUSER_HELPERS))
+ return 0;
+
+ vdso_page = get_zeroed_page(GFP_KERNEL);
+ if (!vdso_page)
+ return -ENOMEM;
+
+ memcpy((void *)(vdso_page + 0x1000 - kuser_sz), __kuser_helper_start,
+ kuser_sz);
+ aarch32_vectors_page = virt_to_page((void *)vdso_page);
+ return 0;
+}
+
+#define COMPAT_SIGPAGE_POISON_WORD 0xe7fddef1
+static int aarch32_alloc_sigpage(void)
+{
+ extern char __aarch32_sigret_code_start[], __aarch32_sigret_code_end[];
+ int sigret_sz = __aarch32_sigret_code_end - __aarch32_sigret_code_start;
+ __le32 poison = cpu_to_le32(COMPAT_SIGPAGE_POISON_WORD);
+ void *sigpage;
+
+ sigpage = (void *)__get_free_page(GFP_KERNEL);
+ if (!sigpage)
+ return -ENOMEM;
+
+ memset32(sigpage, (__force u32)poison, PAGE_SIZE / sizeof(poison));
+ memcpy(sigpage, __aarch32_sigret_code_start, sigret_sz);
+ aarch32_sig_page = virt_to_page(sigpage);
+ return 0;
+}
+
+static int __init __aarch32_alloc_vdso_pages(void)
+{
+
+ if (!IS_ENABLED(CONFIG_COMPAT_VDSO))
+ return 0;
+
+ vdso_info[VDSO_ABI_AA32].dm = &aarch32_vdso_maps[AA32_MAP_VVAR];
+ vdso_info[VDSO_ABI_AA32].cm = &aarch32_vdso_maps[AA32_MAP_VDSO];
+
+ return __vdso_init(VDSO_ABI_AA32);
+}
+
+static int __init aarch32_alloc_vdso_pages(void)
+{
+ int ret;
+
+ ret = __aarch32_alloc_vdso_pages();
+ if (ret)
+ return ret;
+
+ ret = aarch32_alloc_sigpage();
+ if (ret)
+ return ret;
+
+ return aarch32_alloc_kuser_vdso_page();
+}
+arch_initcall(aarch32_alloc_vdso_pages);
+
+static int aarch32_kuser_helpers_setup(struct mm_struct *mm)
+{
+ void *ret;
+
+ if (!IS_ENABLED(CONFIG_KUSER_HELPERS))
+ return 0;
+
+ /*
+ * Avoid VM_MAYWRITE for compatibility with arch/arm/, where it's
+ * not safe to CoW the page containing the CPU exception vectors.
+ */
+ ret = _install_special_mapping(mm, AARCH32_VECTORS_BASE, PAGE_SIZE,
+ VM_READ | VM_EXEC |
+ VM_MAYREAD | VM_MAYEXEC,
+ &aarch32_vdso_maps[AA32_MAP_VECTORS]);
+
+ return PTR_ERR_OR_ZERO(ret);
+}
+
+static int aarch32_sigreturn_setup(struct mm_struct *mm)
+{
+ unsigned long addr;
+ void *ret;
+
+ addr = get_unmapped_area(NULL, 0, PAGE_SIZE, 0, 0);
+ if (IS_ERR_VALUE(addr)) {
+ ret = ERR_PTR(addr);
+ goto out;
+ }
+
+ /*
+ * VM_MAYWRITE is required to allow gdb to Copy-on-Write and
+ * set breakpoints.
+ */
+ ret = _install_special_mapping(mm, addr, PAGE_SIZE,
+ VM_READ | VM_EXEC | VM_MAYREAD |
+ VM_MAYWRITE | VM_MAYEXEC,
+ &aarch32_vdso_maps[AA32_MAP_SIGPAGE]);
+ if (IS_ERR(ret))
+ goto out;
+
+ mm->context.sigpage = (void *)addr;
+
+out:
+ return PTR_ERR_OR_ZERO(ret);
+}
+
+int aarch32_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
+{
+ struct mm_struct *mm = current->mm;
+ int ret;
+
+ if (mmap_write_lock_killable(mm))
+ return -EINTR;
+
+ ret = aarch32_kuser_helpers_setup(mm);
+ if (ret)
+ goto out;
+
+ if (IS_ENABLED(CONFIG_COMPAT_VDSO)) {
+ ret = __setup_additional_pages(VDSO_ABI_AA32, mm, bprm,
+ uses_interp);
+ if (ret)
+ goto out;
+ }
+
+ ret = aarch32_sigreturn_setup(mm);
+out:
+ mmap_write_unlock(mm);
+ return ret;
+}
+#endif /* CONFIG_COMPAT */
+
+enum aarch64_map {
+ AA64_MAP_VVAR,
+ AA64_MAP_VDSO,
+};
+
+static struct vm_special_mapping aarch64_vdso_maps[] __ro_after_init = {
+ [AA64_MAP_VVAR] = {
+ .name = "[vvar]",
+ .fault = vvar_fault,
+ },
+ [AA64_MAP_VDSO] = {
+ .name = "[vdso]",
+ .mremap = vdso_mremap,
+ },
+};
+
+static int __init vdso_init(void)
+{
+ vdso_info[VDSO_ABI_AA64].dm = &aarch64_vdso_maps[AA64_MAP_VVAR];
+ vdso_info[VDSO_ABI_AA64].cm = &aarch64_vdso_maps[AA64_MAP_VDSO];
+
+ return __vdso_init(VDSO_ABI_AA64);
+}
+arch_initcall(vdso_init);
+
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
+{
+ struct mm_struct *mm = current->mm;
+ int ret;
+
+ if (mmap_write_lock_killable(mm))
+ return -EINTR;
+
+ ret = __setup_additional_pages(VDSO_ABI_AA64, mm, bprm, uses_interp);
+ mmap_write_unlock(mm);
+
+ return ret;
+}
diff --git a/arch/arm64/kernel/vdso/.gitignore b/arch/arm64/kernel/vdso/.gitignore
new file mode 100644
index 000000000..652e31d82
--- /dev/null
+++ b/arch/arm64/kernel/vdso/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+vdso.lds
diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
new file mode 100644
index 000000000..619e2dc7e
--- /dev/null
+++ b/arch/arm64/kernel/vdso/Makefile
@@ -0,0 +1,92 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Building a vDSO image for AArch64.
+#
+# Author: Will Deacon <will.deacon@arm.com>
+# Heavily based on the vDSO Makefiles for other archs.
+#
+
+# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
+# the inclusion of generic Makefile.
+ARCH_REL_TYPE_ABS := R_AARCH64_JUMP_SLOT|R_AARCH64_GLOB_DAT|R_AARCH64_ABS64
+include $(srctree)/lib/vdso/Makefile
+
+obj-vdso := vgettimeofday.o note.o sigreturn.o
+
+# Build rules
+targets := $(obj-vdso) vdso.so vdso.so.dbg
+obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
+
+btildflags-$(CONFIG_ARM64_BTI_KERNEL) += -z force-bti
+
+# -Bsymbolic has been added for consistency with arm, the compat vDSO and
+# potential future proofing if we end up with internal calls to the exported
+# routines, as x86 does (see 6f121e548f83 ("x86, vdso: Reimplement vdso.so
+# preparation in build-time C")).
+ldflags-y := -shared -soname=linux-vdso.so.1 --hash-style=sysv \
+ -Bsymbolic --build-id=sha1 -n $(btildflags-y)
+
+ifdef CONFIG_LD_ORPHAN_WARN
+ ldflags-y += --orphan-handling=warn
+endif
+
+ldflags-y += -T
+
+ccflags-y := -fno-common -fno-builtin -fno-stack-protector -ffixed-x18
+ccflags-y += -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO
+
+# -Wmissing-prototypes and -Wmissing-declarations are removed from
+# the CFLAGS of vgettimeofday.c to make possible to build the
+# kernel with CONFIG_WERROR enabled.
+CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) \
+ $(RANDSTRUCT_CFLAGS) $(GCC_PLUGINS_CFLAGS) \
+ $(CC_FLAGS_LTO) $(CC_FLAGS_CFI) \
+ -Wmissing-prototypes -Wmissing-declarations
+KASAN_SANITIZE := n
+KCSAN_SANITIZE := n
+UBSAN_SANITIZE := n
+OBJECT_FILES_NON_STANDARD := y
+KCOV_INSTRUMENT := n
+
+CFLAGS_vgettimeofday.o = -O2 -mcmodel=tiny -fasynchronous-unwind-tables
+
+ifneq ($(c-gettimeofday-y),)
+ CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y)
+endif
+
+# Disable gcov profiling for VDSO code
+GCOV_PROFILE := n
+
+targets += vdso.lds
+CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
+
+# Link rule for the .so file, .lds has to be first
+$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE
+ $(call if_changed,vdsold_and_vdso_check)
+
+# Strip rule for the .so file
+$(obj)/%.so: OBJCOPYFLAGS := -S
+$(obj)/%.so: $(obj)/%.so.dbg FORCE
+ $(call if_changed,objcopy)
+
+# Generate VDSO offsets using helper script
+gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
+quiet_cmd_vdsosym = VDSOSYM $@
+ cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
+
+include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
+ $(call if_changed,vdsosym)
+
+# Actual build commands
+quiet_cmd_vdsold_and_vdso_check = LD $@
+ cmd_vdsold_and_vdso_check = $(cmd_ld); $(cmd_vdso_check)
+
+# Install commands for the unstripped file
+quiet_cmd_vdso_install = INSTALL $@
+ cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
+
+vdso.so: $(obj)/vdso.so.dbg
+ @mkdir -p $(MODLIB)/vdso
+ $(call cmd,vdso_install)
+
+vdso_install: vdso.so
diff --git a/arch/arm64/kernel/vdso/gen_vdso_offsets.sh b/arch/arm64/kernel/vdso/gen_vdso_offsets.sh
new file mode 100755
index 000000000..0387209d6
--- /dev/null
+++ b/arch/arm64/kernel/vdso/gen_vdso_offsets.sh
@@ -0,0 +1,16 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+#
+# Match symbols in the DSO that look like VDSO_*; produce a header file
+# of constant offsets into the shared object.
+#
+# Doing this inside the Makefile will break the $(filter-out) function,
+# causing Kbuild to rebuild the vdso-offsets header file every time.
+#
+# Author: Will Deacon <will.deacon@arm.com>
+#
+
+LC_ALL=C
+sed -n -e 's/^00*/0/' -e \
+'s/^\([0-9a-fA-F]*\) . VDSO_\([a-zA-Z0-9_]*\)$/\#define vdso_offset_\2 0x\1/p'
diff --git a/arch/arm64/kernel/vdso/note.S b/arch/arm64/kernel/vdso/note.S
new file mode 100644
index 000000000..3d4e82290
--- /dev/null
+++ b/arch/arm64/kernel/vdso/note.S
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2012 ARM Limited
+ *
+ * Author: Will Deacon <will.deacon@arm.com>
+ *
+ * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
+ * Here we can supply some information useful to userland.
+ */
+
+#include <linux/uts.h>
+#include <linux/version.h>
+#include <linux/elfnote.h>
+#include <linux/build-salt.h>
+#include <asm/assembler.h>
+
+ELFNOTE_START(Linux, 0, "a")
+ .long LINUX_VERSION_CODE
+ELFNOTE_END
+
+BUILD_SALT
+
+emit_aarch64_feature_1_and
diff --git a/arch/arm64/kernel/vdso/sigreturn.S b/arch/arm64/kernel/vdso/sigreturn.S
new file mode 100644
index 000000000..0e18729ab
--- /dev/null
+++ b/arch/arm64/kernel/vdso/sigreturn.S
@@ -0,0 +1,80 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Sigreturn trampoline for returning from a signal when the SA_RESTORER
+ * flag is not set. It serves primarily as a hall of shame for crappy
+ * unwinders and features an exciting but mysterious NOP instruction.
+ *
+ * It's also fragile as hell, so please think twice before changing anything
+ * in here.
+ *
+ * Copyright (C) 2012 ARM Limited
+ *
+ * Author: Will Deacon <will.deacon@arm.com>
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/unistd.h>
+
+ .text
+
+/*
+ * NOTE!!! You may notice that all of the .cfi directives in this file have
+ * been commented out. This is because they have been shown to trigger segfaults
+ * in libgcc when unwinding out of a SIGCANCEL handler to invoke pthread
+ * cleanup handlers during the thread cancellation dance. By omitting the
+ * directives, we trigger an arm64-specific fallback path in the unwinder which
+ * recognises the signal frame and restores many of the registers directly from
+ * the sigcontext. Re-enabling the cfi directives here therefore needs to be
+ * much more comprehensive to reduce the risk of further regressions.
+ */
+
+/* Ensure that the mysterious NOP can be associated with a function. */
+// .cfi_startproc
+
+/*
+ * .cfi_signal_frame causes the corresponding Frame Description Entry (FDE) in
+ * the .eh_frame section to be annotated as a signal frame. This allows DWARF
+ * unwinders (e.g. libstdc++) to implement _Unwind_GetIPInfo() and identify
+ * the next frame using the unmodified return address instead of subtracting 1,
+ * which may yield the wrong FDE.
+ */
+// .cfi_signal_frame
+
+/*
+ * Tell the unwinder where to locate the frame record linking back to the
+ * interrupted context. We don't provide unwind info for registers other than
+ * the frame pointer and the link register here; in practice, this is likely to
+ * be insufficient for unwinding in C/C++ based runtimes, especially without a
+ * means to restore the stack pointer. Thankfully, unwinders and debuggers
+ * already have baked-in strategies for attempting to unwind out of signals.
+ */
+// .cfi_def_cfa x29, 0
+// .cfi_offset x29, 0 * 8
+// .cfi_offset x30, 1 * 8
+
+/*
+ * This mysterious NOP is required for some unwinders (e.g. libc++) that
+ * unconditionally subtract one from the result of _Unwind_GetIP() in order to
+ * identify the calling function.
+ * Hack borrowed from arch/powerpc/kernel/vdso64/sigtramp.S.
+ */
+ nop // Mysterious NOP
+
+/*
+ * GDB, libgcc and libunwind rely on being able to identify the sigreturn
+ * instruction sequence to unwind from signal handlers. We cannot, therefore,
+ * use SYM_FUNC_START() here, as it will emit a BTI C instruction and break the
+ * unwinder. Thankfully, this function is only ever called from a RET and so
+ * omitting the landing pad is perfectly fine.
+ */
+SYM_CODE_START(__kernel_rt_sigreturn)
+// PLEASE DO NOT MODIFY
+ mov x8, #__NR_rt_sigreturn
+// PLEASE DO NOT MODIFY
+ svc #0
+// PLEASE DO NOT MODIFY
+// .cfi_endproc
+SYM_CODE_END(__kernel_rt_sigreturn)
+
+emit_aarch64_feature_1_and
diff --git a/arch/arm64/kernel/vdso/vdso.lds.S b/arch/arm64/kernel/vdso/vdso.lds.S
new file mode 100644
index 000000000..6028f1fe2
--- /dev/null
+++ b/arch/arm64/kernel/vdso/vdso.lds.S
@@ -0,0 +1,114 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * GNU linker script for the VDSO library.
+*
+ * Copyright (C) 2012 ARM Limited
+ *
+ * Author: Will Deacon <will.deacon@arm.com>
+ * Heavily based on the vDSO linker scripts for other archs.
+ */
+
+#include <linux/const.h>
+#include <asm/page.h>
+#include <asm/vdso.h>
+#include <asm-generic/vmlinux.lds.h>
+
+OUTPUT_FORMAT("elf64-littleaarch64", "elf64-bigaarch64", "elf64-littleaarch64")
+OUTPUT_ARCH(aarch64)
+
+SECTIONS
+{
+ PROVIDE(_vdso_data = . - __VVAR_PAGES * PAGE_SIZE);
+#ifdef CONFIG_TIME_NS
+ PROVIDE(_timens_data = _vdso_data + PAGE_SIZE);
+#endif
+ . = VDSO_LBASE + SIZEOF_HEADERS;
+
+ .hash : { *(.hash) } :text
+ .gnu.hash : { *(.gnu.hash) }
+ .dynsym : { *(.dynsym) }
+ .dynstr : { *(.dynstr) }
+ .gnu.version : { *(.gnu.version) }
+ .gnu.version_d : { *(.gnu.version_d) }
+ .gnu.version_r : { *(.gnu.version_r) }
+
+ /*
+ * Discard .note.gnu.property sections which are unused and have
+ * different alignment requirement from vDSO note sections.
+ */
+ /DISCARD/ : {
+ *(.note.GNU-stack .note.gnu.property)
+ }
+ .note : { *(.note.*) } :text :note
+
+ . = ALIGN(16);
+
+ .text : { *(.text*) } :text =0xd503201f
+ PROVIDE (__etext = .);
+ PROVIDE (_etext = .);
+ PROVIDE (etext = .);
+
+ . = ALIGN(4);
+ .altinstructions : {
+ __alt_instructions = .;
+ *(.altinstructions)
+ __alt_instructions_end = .;
+ }
+
+ .dynamic : { *(.dynamic) } :text :dynamic
+
+ .rela.dyn : ALIGN(8) { *(.rela .rela*) }
+
+ .rodata : {
+ *(.rodata*)
+ *(.got)
+ *(.got.plt)
+ *(.plt)
+ *(.plt.*)
+ *(.iplt)
+ *(.igot .igot.plt)
+ } :text
+
+ _end = .;
+ PROVIDE(end = .);
+
+ DWARF_DEBUG
+ ELF_DETAILS
+
+ /DISCARD/ : {
+ *(.data .data.* .gnu.linkonce.d.* .sdata*)
+ *(.bss .sbss .dynbss .dynsbss)
+ *(.eh_frame .eh_frame_hdr)
+ }
+}
+
+/*
+ * We must supply the ELF program headers explicitly to get just one
+ * PT_LOAD segment, and set the flags explicitly to make segments read-only.
+ */
+PHDRS
+{
+ text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */
+ dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
+ note PT_NOTE FLAGS(4); /* PF_R */
+}
+
+/*
+ * This controls what symbols we export from the DSO.
+ */
+VERSION
+{
+ LINUX_2.6.39 {
+ global:
+ __kernel_rt_sigreturn;
+ __kernel_gettimeofday;
+ __kernel_clock_gettime;
+ __kernel_clock_getres;
+ local: *;
+ };
+}
+
+/*
+ * Make the sigreturn code visible to the kernel.
+ */
+VDSO_sigtramp = __kernel_rt_sigreturn;
diff --git a/arch/arm64/kernel/vdso/vgettimeofday.c b/arch/arm64/kernel/vdso/vgettimeofday.c
new file mode 100644
index 000000000..4236cf34d
--- /dev/null
+++ b/arch/arm64/kernel/vdso/vgettimeofday.c
@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM64 userspace implementations of gettimeofday() and similar.
+ *
+ * Copyright (C) 2018 ARM Limited
+ *
+ */
+
+int __kernel_clock_gettime(clockid_t clock,
+ struct __kernel_timespec *ts)
+{
+ return __cvdso_clock_gettime(clock, ts);
+}
+
+int __kernel_gettimeofday(struct __kernel_old_timeval *tv,
+ struct timezone *tz)
+{
+ return __cvdso_gettimeofday(tv, tz);
+}
+
+int __kernel_clock_getres(clockid_t clock_id,
+ struct __kernel_timespec *res)
+{
+ return __cvdso_clock_getres(clock_id, res);
+}
diff --git a/arch/arm64/kernel/vdso32-wrap.S b/arch/arm64/kernel/vdso32-wrap.S
new file mode 100644
index 000000000..e72ac7bc4
--- /dev/null
+++ b/arch/arm64/kernel/vdso32-wrap.S
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2012 ARM Limited
+ */
+
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <linux/const.h>
+#include <asm/page.h>
+
+ .globl vdso32_start, vdso32_end
+ .section .rodata
+ .balign PAGE_SIZE
+vdso32_start:
+ .incbin "arch/arm64/kernel/vdso32/vdso.so"
+ .balign PAGE_SIZE
+vdso32_end:
+
+ .previous
diff --git a/arch/arm64/kernel/vdso32/.gitignore b/arch/arm64/kernel/vdso32/.gitignore
new file mode 100644
index 000000000..3542fa24e
--- /dev/null
+++ b/arch/arm64/kernel/vdso32/.gitignore
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0-only
+vdso.lds
+vdso.so.raw
diff --git a/arch/arm64/kernel/vdso32/Makefile b/arch/arm64/kernel/vdso32/Makefile
new file mode 100644
index 000000000..36c8f66ca
--- /dev/null
+++ b/arch/arm64/kernel/vdso32/Makefile
@@ -0,0 +1,189 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for vdso32
+#
+
+# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
+# the inclusion of generic Makefile.
+ARCH_REL_TYPE_ABS := R_ARM_JUMP_SLOT|R_ARM_GLOB_DAT|R_ARM_ABS32
+include $(srctree)/lib/vdso/Makefile
+
+# Same as cc-*option, but using CC_COMPAT instead of CC
+ifeq ($(CONFIG_CC_IS_CLANG), y)
+CC_COMPAT ?= $(CC)
+CC_COMPAT += --target=arm-linux-gnueabi
+else
+CC_COMPAT ?= $(CROSS_COMPILE_COMPAT)gcc
+endif
+
+ifeq ($(CONFIG_LD_IS_LLD), y)
+LD_COMPAT ?= $(LD)
+else
+LD_COMPAT ?= $(CROSS_COMPILE_COMPAT)ld
+endif
+
+cc32-option = $(call try-run,\
+ $(CC_COMPAT) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2))
+cc32-disable-warning = $(call try-run,\
+ $(CC_COMPAT) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
+
+# We cannot use the global flags to compile the vDSO files, the main reason
+# being that the 32-bit compiler may be older than the main (64-bit) compiler
+# and therefore may not understand flags set using $(cc-option ...). Besides,
+# arch-specific options should be taken from the arm Makefile instead of the
+# arm64 one.
+# As a result we set our own flags here.
+
+# KBUILD_CPPFLAGS and NOSTDINC_FLAGS from top-level Makefile
+VDSO_CPPFLAGS := -DBUILD_VDSO -D__KERNEL__ -nostdinc
+VDSO_CPPFLAGS += -isystem $(shell $(CC_COMPAT) -print-file-name=include 2>/dev/null)
+VDSO_CPPFLAGS += $(LINUXINCLUDE)
+
+# Common C and assembly flags
+# From top-level Makefile
+VDSO_CAFLAGS := $(VDSO_CPPFLAGS)
+VDSO_CAFLAGS += $(call cc32-option,-fno-PIE)
+ifdef CONFIG_DEBUG_INFO
+VDSO_CAFLAGS += -g
+endif
+
+# From arm Makefile
+VDSO_CAFLAGS += $(call cc32-option,-fno-dwarf2-cfi-asm)
+VDSO_CAFLAGS += -mabi=aapcs-linux -mfloat-abi=soft
+ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
+VDSO_CAFLAGS += -mbig-endian
+else
+VDSO_CAFLAGS += -mlittle-endian
+endif
+
+# From arm vDSO Makefile
+VDSO_CAFLAGS += -fPIC -fno-builtin -fno-stack-protector
+VDSO_CAFLAGS += -DDISABLE_BRANCH_PROFILING
+VDSO_CAFLAGS += -march=armv8-a
+
+VDSO_CFLAGS := $(VDSO_CAFLAGS)
+VDSO_CFLAGS += -DENABLE_COMPAT_VDSO=1
+# KBUILD_CFLAGS from top-level Makefile
+VDSO_CFLAGS += -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
+ -fno-strict-aliasing -fno-common \
+ -Werror-implicit-function-declaration \
+ -Wno-format-security \
+ -Wdeclaration-after-statement \
+ -std=gnu11
+VDSO_CFLAGS += -O2
+# Some useful compiler-dependent flags from top-level Makefile
+VDSO_CFLAGS += $(call cc32-option,-Wdeclaration-after-statement,)
+VDSO_CFLAGS += $(call cc32-option,-Wno-pointer-sign)
+VDSO_CFLAGS += -fno-strict-overflow
+VDSO_CFLAGS += $(call cc32-option,-Werror=strict-prototypes)
+VDSO_CFLAGS += -Werror=date-time
+VDSO_CFLAGS += $(call cc32-option,-Werror=incompatible-pointer-types)
+
+# The 32-bit compiler does not provide 128-bit integers, which are used in
+# some headers that are indirectly included from the vDSO code.
+# This hack makes the compiler happy and should trigger a warning/error if
+# variables of such type are referenced.
+VDSO_CFLAGS += -D__uint128_t='void*'
+# Silence some warnings coming from headers that operate on long's
+# (on GCC 4.8 or older, there is unfortunately no way to silence this warning)
+VDSO_CFLAGS += $(call cc32-disable-warning,shift-count-overflow)
+VDSO_CFLAGS += -Wno-int-to-pointer-cast
+
+# Compile as THUMB2 or ARM. Unwinding via frame-pointers in THUMB2 is
+# unreliable.
+ifeq ($(CONFIG_THUMB2_COMPAT_VDSO), y)
+VDSO_CFLAGS += -mthumb -fomit-frame-pointer
+else
+VDSO_CFLAGS += -marm
+endif
+
+VDSO_AFLAGS := $(VDSO_CAFLAGS)
+VDSO_AFLAGS += -D__ASSEMBLY__
+
+# From arm vDSO Makefile
+VDSO_LDFLAGS += -Bsymbolic --no-undefined -soname=linux-vdso.so.1
+VDSO_LDFLAGS += -z max-page-size=4096 -z common-page-size=4096
+VDSO_LDFLAGS += -shared --hash-style=sysv --build-id=sha1
+VDSO_LDFLAGS += --orphan-handling=warn
+
+
+# Borrow vdsomunge.c from the arm vDSO
+# We have to use a relative path because scripts/Makefile.host prefixes
+# $(hostprogs) with $(obj)
+munge := ../../../arm/vdso/vdsomunge
+hostprogs := $(munge)
+
+c-obj-vdso := note.o
+c-obj-vdso-gettimeofday := vgettimeofday.o
+
+ifneq ($(c-gettimeofday-y),)
+VDSO_CFLAGS_gettimeofday_o += -include $(c-gettimeofday-y)
+endif
+
+VDSO_CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os
+
+# Build rules
+targets := $(c-obj-vdso) $(c-obj-vdso-gettimeofday) $(asm-obj-vdso) vdso.so vdso.so.dbg vdso.so.raw
+c-obj-vdso := $(addprefix $(obj)/, $(c-obj-vdso))
+c-obj-vdso-gettimeofday := $(addprefix $(obj)/, $(c-obj-vdso-gettimeofday))
+asm-obj-vdso := $(addprefix $(obj)/, $(asm-obj-vdso))
+obj-vdso := $(c-obj-vdso) $(c-obj-vdso-gettimeofday) $(asm-obj-vdso)
+
+targets += vdso.lds
+CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
+
+include/generated/vdso32-offsets.h: $(obj)/vdso.so.dbg FORCE
+ $(call if_changed,vdsosym)
+
+# Strip rule for vdso.so
+$(obj)/vdso.so: OBJCOPYFLAGS := -S
+$(obj)/vdso.so: $(obj)/vdso.so.dbg FORCE
+ $(call if_changed,objcopy)
+
+$(obj)/vdso.so.dbg: $(obj)/vdso.so.raw $(obj)/$(munge) FORCE
+ $(call if_changed,vdsomunge)
+
+# Link rule for the .so file, .lds has to be first
+$(obj)/vdso.so.raw: $(src)/vdso.lds $(obj-vdso) FORCE
+ $(call if_changed,vdsold_and_vdso_check)
+
+# Compilation rules for the vDSO sources
+$(c-obj-vdso): %.o: %.c FORCE
+ $(call if_changed_dep,vdsocc)
+$(c-obj-vdso-gettimeofday): %.o: %.c FORCE
+ $(call if_changed_dep,vdsocc_gettimeofday)
+$(asm-obj-vdso): %.o: %.S FORCE
+ $(call if_changed_dep,vdsoas)
+
+# Actual build commands
+quiet_cmd_vdsold_and_vdso_check = LD32 $@
+ cmd_vdsold_and_vdso_check = $(cmd_vdsold); $(cmd_vdso_check)
+
+quiet_cmd_vdsold = LD32 $@
+ cmd_vdsold = $(LD_COMPAT) $(VDSO_LDFLAGS) \
+ -T $(filter %.lds,$^) $(filter %.o,$^) -o $@
+quiet_cmd_vdsocc = CC32 $@
+ cmd_vdsocc = $(CC_COMPAT) -Wp,-MD,$(depfile) $(VDSO_CFLAGS) -c -o $@ $<
+quiet_cmd_vdsocc_gettimeofday = CC32 $@
+ cmd_vdsocc_gettimeofday = $(CC_COMPAT) -Wp,-MD,$(depfile) $(VDSO_CFLAGS) $(VDSO_CFLAGS_gettimeofday_o) -c -o $@ $<
+quiet_cmd_vdsoas = AS32 $@
+ cmd_vdsoas = $(CC_COMPAT) -Wp,-MD,$(depfile) $(VDSO_AFLAGS) -c -o $@ $<
+
+quiet_cmd_vdsomunge = MUNGE $@
+ cmd_vdsomunge = $(obj)/$(munge) $< $@
+
+# Generate vDSO offsets using helper script (borrowed from the 64-bit vDSO)
+gen-vdsosym := $(srctree)/$(src)/../vdso/gen_vdso_offsets.sh
+quiet_cmd_vdsosym = VDSOSYM $@
+# The AArch64 nm should be able to read an AArch32 binary
+ cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
+
+# Install commands for the unstripped file
+quiet_cmd_vdso_install = INSTALL32 $@
+ cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/vdso32.so
+
+vdso.so: $(obj)/vdso.so.dbg
+ @mkdir -p $(MODLIB)/vdso
+ $(call cmd,vdso_install)
+
+vdso_install: vdso.so
diff --git a/arch/arm64/kernel/vdso32/note.c b/arch/arm64/kernel/vdso32/note.c
new file mode 100644
index 000000000..eff5bf9ef
--- /dev/null
+++ b/arch/arm64/kernel/vdso32/note.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2012-2018 ARM Limited
+ *
+ * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
+ * Here we can supply some information useful to userland.
+ */
+
+#include <linux/uts.h>
+#include <linux/version.h>
+#include <linux/elfnote.h>
+#include <linux/build-salt.h>
+
+ELFNOTE32("Linux", 0, LINUX_VERSION_CODE);
+BUILD_SALT;
diff --git a/arch/arm64/kernel/vdso32/vdso.lds.S b/arch/arm64/kernel/vdso32/vdso.lds.S
new file mode 100644
index 000000000..8d95d7d35
--- /dev/null
+++ b/arch/arm64/kernel/vdso32/vdso.lds.S
@@ -0,0 +1,92 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Adapted from arm64 version.
+ *
+ * GNU linker script for the VDSO library.
+ * Heavily based on the vDSO linker scripts for other archs.
+ *
+ * Copyright (C) 2012-2018 ARM Limited
+ */
+
+#include <linux/const.h>
+#include <asm/page.h>
+#include <asm/vdso.h>
+#include <asm-generic/vmlinux.lds.h>
+
+OUTPUT_FORMAT("elf32-littlearm", "elf32-bigarm", "elf32-littlearm")
+OUTPUT_ARCH(arm)
+
+SECTIONS
+{
+ PROVIDE_HIDDEN(_vdso_data = . - __VVAR_PAGES * PAGE_SIZE);
+#ifdef CONFIG_TIME_NS
+ PROVIDE_HIDDEN(_timens_data = _vdso_data + PAGE_SIZE);
+#endif
+ . = VDSO_LBASE + SIZEOF_HEADERS;
+
+ .hash : { *(.hash) } :text
+ .gnu.hash : { *(.gnu.hash) }
+ .dynsym : { *(.dynsym) }
+ .dynstr : { *(.dynstr) }
+ .gnu.version : { *(.gnu.version) }
+ .gnu.version_d : { *(.gnu.version_d) }
+ .gnu.version_r : { *(.gnu.version_r) }
+
+ .note : { *(.note.*) } :text :note
+
+ .dynamic : { *(.dynamic) } :text :dynamic
+
+ .rodata : {
+ *(.rodata*)
+ *(.got)
+ *(.got.plt)
+ *(.plt)
+ *(.rel.iplt)
+ *(.iplt)
+ *(.igot.plt)
+ } :text
+
+ .text : {
+ *(.text*)
+ *(.glue_7)
+ *(.glue_7t)
+ *(.vfp11_veneer)
+ *(.v4_bx)
+ } :text =0xe7f001f2
+
+ .rel.dyn : { *(.rel*) }
+
+ .ARM.exidx : { *(.ARM.exidx*) }
+ DWARF_DEBUG
+ ELF_DETAILS
+ .ARM.attributes 0 : { *(.ARM.attributes) }
+
+ /DISCARD/ : {
+ *(.note.GNU-stack)
+ *(.data .data.* .gnu.linkonce.d.* .sdata*)
+ *(.bss .sbss .dynbss .dynsbss)
+ }
+}
+
+/*
+ * We must supply the ELF program headers explicitly to get just one
+ * PT_LOAD segment, and set the flags explicitly to make segments read-only.
+ */
+PHDRS
+{
+ text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */
+ dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
+ note PT_NOTE FLAGS(4); /* PF_R */
+}
+
+VERSION
+{
+ LINUX_2.6 {
+ global:
+ __vdso_clock_gettime;
+ __vdso_gettimeofday;
+ __vdso_clock_getres;
+ __vdso_clock_gettime64;
+ local: *;
+ };
+}
diff --git a/arch/arm64/kernel/vdso32/vgettimeofday.c b/arch/arm64/kernel/vdso32/vgettimeofday.c
new file mode 100644
index 000000000..5acff29c5
--- /dev/null
+++ b/arch/arm64/kernel/vdso32/vgettimeofday.c
@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM64 compat userspace implementations of gettimeofday() and similar.
+ *
+ * Copyright (C) 2018 ARM Limited
+ *
+ */
+
+int __vdso_clock_gettime(clockid_t clock,
+ struct old_timespec32 *ts)
+{
+ return __cvdso_clock_gettime32(clock, ts);
+}
+
+int __vdso_clock_gettime64(clockid_t clock,
+ struct __kernel_timespec *ts)
+{
+ return __cvdso_clock_gettime(clock, ts);
+}
+
+int __vdso_gettimeofday(struct __kernel_old_timeval *tv,
+ struct timezone *tz)
+{
+ return __cvdso_gettimeofday(tv, tz);
+}
+
+int __vdso_clock_getres(clockid_t clock_id,
+ struct old_timespec32 *res)
+{
+ return __cvdso_clock_getres_time32(clock_id, res);
+}
+
+/* Avoid unresolved references emitted by GCC */
+
+void __aeabi_unwind_cpp_pr0(void)
+{
+}
+
+void __aeabi_unwind_cpp_pr1(void)
+{
+}
+
+void __aeabi_unwind_cpp_pr2(void)
+{
+}