[PATCH 2/4] ORC: pull out module handling from x86/loongarch
Johannes Berg
johannes at sipsolutions.net
Thu Sep 24 05:35:51 PDT 2026
From: Johannes Berg <johannes.berg at intel.com>
The x86 and loongarch code for ORC unwinder are just
copied code, and I don't want to add another copy for
UML. Pull out the common module section handling into
the regular module code to reduce duplication.
I used the x86 version, but loongarch is identical
except for variable declaration order.
Signed-off-by: Johannes Berg <johannes.berg at intel.com>
---
MAINTAINERS | 2 +
arch/loongarch/include/asm/module.h | 7 --
arch/loongarch/include/asm/unwind.h | 2 -
arch/loongarch/kernel/module.c | 10 +--
arch/loongarch/kernel/unwind_orc.c | 128 +---------------------------
arch/x86/include/asm/module.h | 6 --
arch/x86/include/asm/unwind.h | 5 --
arch/x86/kernel/module.c | 10 ---
arch/x86/kernel/unwind_orc.c | 127 +--------------------------
include/linux/module.h | 7 ++
include/linux/moduleloader.h | 6 ++
include/linux/orc.h | 24 ++++++
kernel/module/main.c | 23 ++++-
lib/Makefile | 3 +
lib/orc.c | 119 ++++++++++++++++++++++++++
15 files changed, 186 insertions(+), 293 deletions(-)
create mode 100644 include/linux/orc.h
create mode 100644 lib/orc.c
diff --git a/MAINTAINERS b/MAINTAINERS
index cc3cae2e378b..f1911d21a2eb 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -29636,6 +29636,8 @@ F: arch/x86/include/asm/unwind*.h
F: arch/x86/kernel/dumpstack.c
F: arch/x86/kernel/stacktrace.c
F: arch/x86/kernel/unwind_*.c
+F: include/linux/orc.h
+F: lib/orc.c
X86 TRUST DOMAIN EXTENSIONS (TDX)
M: Kiryl Shutsemau <kas at kernel.org>
diff --git a/arch/loongarch/include/asm/module.h b/arch/loongarch/include/asm/module.h
index d56a968273de..cc421db73ed4 100644
--- a/arch/loongarch/include/asm/module.h
+++ b/arch/loongarch/include/asm/module.h
@@ -6,7 +6,6 @@
#define _ASM_MODULE_H
#include <asm/inst.h>
-#include <asm/orc_types.h>
#include <asm-generic/module.h>
#define RELA_STACK_DEPTH 16
@@ -22,12 +21,6 @@ struct mod_arch_specific {
struct mod_section plt;
struct mod_section plt_idx;
-#ifdef CONFIG_UNWINDER_ORC
- unsigned int num_orcs;
- int *orc_unwind_ip;
- struct orc_entry *orc_unwind;
-#endif
-
/* For CONFIG_DYNAMIC_FTRACE */
struct plt_entry *ftrace_trampolines;
};
diff --git a/arch/loongarch/include/asm/unwind.h b/arch/loongarch/include/asm/unwind.h
index 40a6763c5aec..7a5f1458373f 100644
--- a/arch/loongarch/include/asm/unwind.h
+++ b/arch/loongarch/include/asm/unwind.h
@@ -89,10 +89,8 @@ static __always_inline unsigned long __unwind_get_return_address(struct unwind_s
#ifdef CONFIG_UNWINDER_ORC
void unwind_init(void);
-void unwind_module_init(struct module *mod, void *orc_ip, size_t orc_ip_size, void *orc, size_t orc_size);
#else
static inline void unwind_init(void) {}
-static inline void unwind_module_init(struct module *mod, void *orc_ip, size_t orc_ip_size, void *orc, size_t orc_size) {}
#endif
#endif /* _ASM_UNWIND_H */
diff --git a/arch/loongarch/kernel/module.c b/arch/loongarch/kernel/module.c
index 7d4d571ee55e..21f7542003d4 100644
--- a/arch/loongarch/kernel/module.c
+++ b/arch/loongarch/kernel/module.c
@@ -20,7 +20,6 @@
#include <linux/kernel.h>
#include <asm/alternative.h>
#include <asm/inst.h>
-#include <asm/unwind.h>
/*
* reloc_rela_handler() - Apply a particular relocation to a module
@@ -607,15 +606,11 @@ int module_finalize(const Elf_Ehdr *hdr,
const Elf_Shdr *sechdrs, struct module *mod)
{
const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
- const Elf_Shdr *s, *alt = NULL, *orc = NULL, *orc_ip = NULL, *ftrace = NULL;
+ const Elf_Shdr *s, *alt = NULL, *ftrace = NULL;
for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
if (!strcmp(".altinstructions", secstrs + s->sh_name))
alt = s;
- if (!strcmp(".orc_unwind", secstrs + s->sh_name))
- orc = s;
- if (!strcmp(".orc_unwind_ip", secstrs + s->sh_name))
- orc_ip = s;
if (!strcmp(".ftrace_trampoline", secstrs + s->sh_name))
ftrace = s;
}
@@ -623,9 +618,6 @@ int module_finalize(const Elf_Ehdr *hdr,
if (alt)
apply_alternatives((void *)alt->sh_addr, (void *)alt->sh_addr + alt->sh_size);
- if (orc && orc_ip)
- unwind_module_init(mod, (void *)orc_ip->sh_addr, orc_ip->sh_size, (void *)orc->sh_addr, orc->sh_size);
-
if (ftrace)
module_init_ftrace_plt(hdr, ftrace, mod);
diff --git a/arch/loongarch/kernel/unwind_orc.c b/arch/loongarch/kernel/unwind_orc.c
index 9cfb5bb1991f..129f248836a7 100644
--- a/arch/loongarch/kernel/unwind_orc.c
+++ b/arch/loongarch/kernel/unwind_orc.c
@@ -2,7 +2,7 @@
#include <linux/export.h>
#include <linux/module.h>
#include <linux/objtool.h>
-#include <linux/sort.h>
+#include <linux/orc.h>
#include <asm/exception.h>
#include <asm/orc_header.h>
#include <asm/orc_lookup.h>
@@ -51,58 +51,6 @@ static struct orc_entry orc_null_entry = {
.type = ORC_TYPE_CALL
};
-static inline unsigned long orc_ip(const int *ip)
-{
- return (unsigned long)ip + *ip;
-}
-
-static struct orc_entry *__orc_find(int *ip_table, struct orc_entry *u_table,
- unsigned int num_entries, unsigned long ip)
-{
- int *first = ip_table;
- int *mid = first, *found = first;
- int *last = ip_table + num_entries - 1;
-
- if (!num_entries)
- return NULL;
-
- /*
- * Do a binary range search to find the rightmost duplicate of a given
- * starting address. Some entries are section terminators which are
- * "weak" entries for ensuring there are no gaps. They should be
- * ignored when they conflict with a real entry.
- */
- while (first <= last) {
- mid = first + ((last - first) / 2);
-
- if (orc_ip(mid) <= ip) {
- found = mid;
- first = mid + 1;
- } else
- last = mid - 1;
- }
-
- return u_table + (found - ip_table);
-}
-
-#ifdef CONFIG_MODULES
-static struct orc_entry *orc_module_find(unsigned long ip)
-{
- struct module *mod;
-
- mod = __module_address(ip);
- if (!mod || !mod->arch.orc_unwind || !mod->arch.orc_unwind_ip)
- return NULL;
-
- return __orc_find(mod->arch.orc_unwind_ip, mod->arch.orc_unwind, mod->arch.num_orcs, ip);
-}
-#else
-static struct orc_entry *orc_module_find(unsigned long ip)
-{
- return NULL;
-}
-#endif
-
#ifdef CONFIG_DYNAMIC_FTRACE
static struct orc_entry *orc_find(unsigned long ip);
@@ -194,80 +142,6 @@ static struct orc_entry *orc_find(unsigned long ip)
return orc_ftrace_find(ip);
}
-#ifdef CONFIG_MODULES
-
-static DEFINE_MUTEX(sort_mutex);
-static int *cur_orc_ip_table = __start_orc_unwind_ip;
-static struct orc_entry *cur_orc_table = __start_orc_unwind;
-
-static void orc_sort_swap(void *_a, void *_b, int size)
-{
- int delta = _b - _a;
- int *a = _a, *b = _b, tmp;
- struct orc_entry *orc_a, *orc_b;
-
- /* Swap the .orc_unwind_ip entries: */
- tmp = *a;
- *a = *b + delta;
- *b = tmp - delta;
-
- /* Swap the corresponding .orc_unwind entries: */
- orc_a = cur_orc_table + (a - cur_orc_ip_table);
- orc_b = cur_orc_table + (b - cur_orc_ip_table);
- swap(*orc_a, *orc_b);
-}
-
-static int orc_sort_cmp(const void *_a, const void *_b)
-{
- const int *a = _a, *b = _b;
- unsigned long a_val = orc_ip(a);
- unsigned long b_val = orc_ip(b);
- struct orc_entry *orc_a;
-
- if (a_val > b_val)
- return 1;
- if (a_val < b_val)
- return -1;
-
- /*
- * The "weak" section terminator entries need to always be first
- * to ensure the lookup code skips them in favor of real entries.
- * These terminator entries exist to handle any gaps created by
- * whitelisted .o files which didn't get objtool generation.
- */
- orc_a = cur_orc_table + (a - cur_orc_ip_table);
-
- return orc_a->type == ORC_TYPE_UNDEFINED ? -1 : 1;
-}
-
-void unwind_module_init(struct module *mod, void *_orc_ip, size_t orc_ip_size,
- void *_orc, size_t orc_size)
-{
- int *orc_ip = _orc_ip;
- struct orc_entry *orc = _orc;
- unsigned int num_entries = orc_ip_size / sizeof(int);
-
- WARN_ON_ONCE(orc_ip_size % sizeof(int) != 0 ||
- orc_size % sizeof(*orc) != 0 ||
- num_entries != orc_size / sizeof(*orc));
-
- /*
- * The 'cur_orc_*' globals allow the orc_sort_swap() callback to
- * associate an .orc_unwind_ip table entry with its corresponding
- * .orc_unwind entry so they can both be swapped.
- */
- mutex_lock(&sort_mutex);
- cur_orc_ip_table = orc_ip;
- cur_orc_table = orc;
- sort(orc_ip, num_entries, sizeof(int), orc_sort_cmp, orc_sort_swap);
- mutex_unlock(&sort_mutex);
-
- mod->arch.orc_unwind_ip = orc_ip;
- mod->arch.orc_unwind = orc;
- mod->arch.num_orcs = num_entries;
-}
-#endif
-
void __init unwind_init(void)
{
int i;
diff --git a/arch/x86/include/asm/module.h b/arch/x86/include/asm/module.h
index 3c2de4ce3b10..6717e85e8605 100644
--- a/arch/x86/include/asm/module.h
+++ b/arch/x86/include/asm/module.h
@@ -3,7 +3,6 @@
#define _ASM_X86_MODULE_H
#include <asm-generic/module.h>
-#include <asm/orc_types.h>
struct its_array {
#ifdef CONFIG_MITIGATION_ITS
@@ -13,11 +12,6 @@ struct its_array {
};
struct mod_arch_specific {
-#ifdef CONFIG_UNWINDER_ORC
- unsigned int num_orcs;
- int *orc_unwind_ip;
- struct orc_entry *orc_unwind;
-#endif
struct its_array its_pages;
};
diff --git a/arch/x86/include/asm/unwind.h b/arch/x86/include/asm/unwind.h
index 7cede4dc21f0..71af8246c69e 100644
--- a/arch/x86/include/asm/unwind.h
+++ b/arch/x86/include/asm/unwind.h
@@ -94,13 +94,8 @@ static inline struct pt_regs *unwind_get_entry_regs(struct unwind_state *state,
#ifdef CONFIG_UNWINDER_ORC
void unwind_init(void);
-void unwind_module_init(struct module *mod, void *orc_ip, size_t orc_ip_size,
- void *orc, size_t orc_size);
#else
static inline void unwind_init(void) {}
-static inline
-void unwind_module_init(struct module *mod, void *orc_ip, size_t orc_ip_size,
- void *orc, size_t orc_size) {}
#endif
static inline
diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c
index 33080ad889b7..cf59f9f42d0b 100644
--- a/arch/x86/kernel/module.c
+++ b/arch/x86/kernel/module.c
@@ -23,7 +23,6 @@
#include <asm/text-patching.h>
#include <asm/page.h>
#include <asm/setup.h>
-#include <asm/unwind.h>
#if 0
#define DEBUGP(fmt, ...) \
@@ -228,7 +227,6 @@ int module_finalize(const Elf_Ehdr *hdr,
struct module *me)
{
const Elf_Shdr *s, *alt = NULL,
- *orc = NULL, *orc_ip = NULL,
*retpolines = NULL, *returns = NULL, *ibt_endbr = NULL,
*calls = NULL, *cfi = NULL;
char *secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
@@ -236,10 +234,6 @@ int module_finalize(const Elf_Ehdr *hdr,
for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
if (!strcmp(".altinstructions", secstrings + s->sh_name))
alt = s;
- if (!strcmp(".orc_unwind", secstrings + s->sh_name))
- orc = s;
- if (!strcmp(".orc_unwind_ip", secstrings + s->sh_name))
- orc_ip = s;
if (!strcmp(".retpoline_sites", secstrings + s->sh_name))
retpolines = s;
if (!strcmp(".return_sites", secstrings + s->sh_name))
@@ -299,10 +293,6 @@ int module_finalize(const Elf_Ehdr *hdr,
apply_seal_endbr(iseg, iseg + ibt_endbr->sh_size);
}
- if (orc && orc_ip)
- unwind_module_init(me, (void *)orc_ip->sh_addr, orc_ip->sh_size,
- (void *)orc->sh_addr, orc->sh_size);
-
return 0;
}
diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c
index 6407bc9256bf..6ea1ea28e9df 100644
--- a/arch/x86/kernel/unwind_orc.c
+++ b/arch/x86/kernel/unwind_orc.c
@@ -1,7 +1,7 @@
// SPDX-License-Identifier: GPL-2.0-only
#include <linux/objtool.h>
#include <linux/module.h>
-#include <linux/sort.h>
+#include <linux/orc.h>
#include <linux/bpf.h>
#include <asm/ptrace.h>
#include <asm/stacktrace.h>
@@ -76,58 +76,6 @@ static void unwind_dump(struct unwind_state *state)
}
}
-static inline unsigned long orc_ip(const int *ip)
-{
- return (unsigned long)ip + *ip;
-}
-
-static struct orc_entry *__orc_find(int *ip_table, struct orc_entry *u_table,
- unsigned int num_entries, unsigned long ip)
-{
- int *first = ip_table;
- int *last = ip_table + num_entries - 1;
- int *mid, *found = first;
-
- if (!num_entries)
- return NULL;
-
- /*
- * Do a binary range search to find the rightmost duplicate of a given
- * starting address. Some entries are section terminators which are
- * "weak" entries for ensuring there are no gaps. They should be
- * ignored when they conflict with a real entry.
- */
- while (first <= last) {
- mid = first + ((last - first) / 2);
-
- if (orc_ip(mid) <= ip) {
- found = mid;
- first = mid + 1;
- } else
- last = mid - 1;
- }
-
- return u_table + (found - ip_table);
-}
-
-#ifdef CONFIG_MODULES
-static struct orc_entry *orc_module_find(unsigned long ip)
-{
- struct module *mod;
-
- mod = __module_address(ip);
- if (!mod || !mod->arch.orc_unwind || !mod->arch.orc_unwind_ip)
- return NULL;
- return __orc_find(mod->arch.orc_unwind_ip, mod->arch.orc_unwind,
- mod->arch.num_orcs, ip);
-}
-#else
-static struct orc_entry *orc_module_find(unsigned long ip)
-{
- return NULL;
-}
-#endif
-
#ifdef CONFIG_DYNAMIC_FTRACE
static struct orc_entry *orc_find(unsigned long ip);
@@ -257,79 +205,6 @@ static struct orc_entry *orc_find(unsigned long ip)
return orc_ftrace_find(ip);
}
-#ifdef CONFIG_MODULES
-
-static DEFINE_MUTEX(sort_mutex);
-static int *cur_orc_ip_table = __start_orc_unwind_ip;
-static struct orc_entry *cur_orc_table = __start_orc_unwind;
-
-static void orc_sort_swap(void *_a, void *_b, int size)
-{
- struct orc_entry *orc_a, *orc_b;
- int *a = _a, *b = _b, tmp;
- int delta = _b - _a;
-
- /* Swap the .orc_unwind_ip entries: */
- tmp = *a;
- *a = *b + delta;
- *b = tmp - delta;
-
- /* Swap the corresponding .orc_unwind entries: */
- orc_a = cur_orc_table + (a - cur_orc_ip_table);
- orc_b = cur_orc_table + (b - cur_orc_ip_table);
- swap(*orc_a, *orc_b);
-}
-
-static int orc_sort_cmp(const void *_a, const void *_b)
-{
- struct orc_entry *orc_a;
- const int *a = _a, *b = _b;
- unsigned long a_val = orc_ip(a);
- unsigned long b_val = orc_ip(b);
-
- if (a_val > b_val)
- return 1;
- if (a_val < b_val)
- return -1;
-
- /*
- * The "weak" section terminator entries need to always be first
- * to ensure the lookup code skips them in favor of real entries.
- * These terminator entries exist to handle any gaps created by
- * whitelisted .o files which didn't get objtool generation.
- */
- orc_a = cur_orc_table + (a - cur_orc_ip_table);
- return orc_a->type == ORC_TYPE_UNDEFINED ? -1 : 1;
-}
-
-void unwind_module_init(struct module *mod, void *_orc_ip, size_t orc_ip_size,
- void *_orc, size_t orc_size)
-{
- int *orc_ip = _orc_ip;
- struct orc_entry *orc = _orc;
- unsigned int num_entries = orc_ip_size / sizeof(int);
-
- WARN_ON_ONCE(orc_ip_size % sizeof(int) != 0 ||
- orc_size % sizeof(*orc) != 0 ||
- num_entries != orc_size / sizeof(*orc));
-
- /*
- * The 'cur_orc_*' globals allow the orc_sort_swap() callback to
- * associate an .orc_unwind_ip table entry with its corresponding
- * .orc_unwind entry so they can both be swapped.
- */
- mutex_lock(&sort_mutex);
- cur_orc_ip_table = orc_ip;
- cur_orc_table = orc;
- sort(orc_ip, num_entries, sizeof(int), orc_sort_cmp, orc_sort_swap);
- mutex_unlock(&sort_mutex);
-
- mod->arch.orc_unwind_ip = orc_ip;
- mod->arch.orc_unwind = orc;
- mod->arch.num_orcs = num_entries;
-}
-#endif
-
void __init unwind_init(void)
{
size_t orc_ip_size = (void *)__stop_orc_unwind_ip - (void *)__start_orc_unwind_ip;
diff --git a/include/linux/module.h b/include/linux/module.h
index 96cc98568eea..089b34c83eb0 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -42,6 +42,7 @@ struct modversion_info {
struct module;
struct exception_table_entry;
+struct orc_entry;
struct module_kobject {
struct kobject kobj;
@@ -465,6 +466,12 @@ struct module {
struct bug_entry *bug_table;
#endif
+#ifdef CONFIG_UNWINDER_ORC
+ unsigned int num_orcs;
+ int *orc_unwind_ip;
+ struct orc_entry *orc_unwind;
+#endif
+
#ifdef CONFIG_KALLSYMS
/* Protected by RCU and/or module_mutex: use rcu_dereference() */
struct mod_kallsyms __rcu *kallsyms;
diff --git a/include/linux/moduleloader.h b/include/linux/moduleloader.h
index e395461d59e5..893ca5717383 100644
--- a/include/linux/moduleloader.h
+++ b/include/linux/moduleloader.h
@@ -108,6 +108,12 @@ int module_finalize(const Elf_Ehdr *hdr,
const Elf_Shdr *sechdrs,
struct module *mod);
+#ifdef CONFIG_UNWINDER_ORC
+/* Sort the module's ORC tables and make them available to the unwinder. */
+void unwind_module_init(struct module *mod, void *orc_ip, size_t orc_ip_size,
+ void *orc, size_t orc_size);
+#endif
+
#ifdef CONFIG_MODULES
void flush_module_init_free_work(void);
#else
diff --git a/include/linux/orc.h b/include/linux/orc.h
new file mode 100644
index 000000000000..c2e84cf85132
--- /dev/null
+++ b/include/linux/orc.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_ORC_H
+#define _LINUX_ORC_H
+
+#include <asm/orc_types.h>
+
+static inline unsigned long orc_ip(const int *ip)
+{
+ return (unsigned long)ip + *ip;
+}
+
+struct orc_entry *__orc_find(int *ip_table, struct orc_entry *u_table,
+ unsigned int num_entries, unsigned long ip);
+
+#ifdef CONFIG_MODULES
+struct orc_entry *orc_module_find(unsigned long ip);
+#else
+static inline struct orc_entry *orc_module_find(unsigned long ip)
+{
+ return NULL;
+}
+#endif
+
+#endif /* _LINUX_ORC_H */
diff --git a/kernel/module/main.c b/kernel/module/main.c
index d0e1e0bd2ad0..d0cbaa2a5d0c 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -3015,8 +3015,24 @@ int __weak module_finalize(const Elf_Ehdr *hdr,
return 0;
}
+static void module_unwind_init(struct module *mod, const struct load_info *info)
+{
+#ifdef CONFIG_UNWINDER_ORC
+ unsigned int orc = find_sec(info, ".orc_unwind");
+ unsigned int orc_ip = find_sec(info, ".orc_unwind_ip");
+
+ if (orc && orc_ip)
+ unwind_module_init(mod, (void *)info->sechdrs[orc_ip].sh_addr,
+ info->sechdrs[orc_ip].sh_size,
+ (void *)info->sechdrs[orc].sh_addr,
+ info->sechdrs[orc].sh_size);
+#endif
+}
+
static int post_relocation(struct module *mod, const struct load_info *info)
{
+ int err;
+
/* Sort exception table now relocations are done. */
sort_extable(mod->extable, mod->extable + mod->num_exentries);
@@ -3028,7 +3044,12 @@ static int post_relocation(struct module *mod, const struct load_info *info)
add_kallsyms(mod, info);
/* Arch-specific module finalizing. */
- return module_finalize(info->hdr, info->sechdrs, mod);
+ err = module_finalize(info->hdr, info->sechdrs, mod);
+ if (err)
+ return err;
+
+ module_unwind_init(mod, info);
+ return 0;
}
/* Call module constructors. */
diff --git a/lib/Makefile b/lib/Makefile
index dfab958327c5..1ccd88ca9e7b 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -255,6 +255,9 @@ KASAN_SANITIZE_stackdepot.o := n
KMSAN_SANITIZE_stackdepot.o := n
KCOV_INSTRUMENT_stackdepot.o := n
+obj-$(CONFIG_UNWINDER_ORC) += orc.o
+KCOV_INSTRUMENT_orc.o := n
+
obj-$(CONFIG_REF_TRACKER) += ref_tracker.o
libfdt_files = fdt.o fdt_ro.o fdt_wip.o fdt_rw.o fdt_sw.o fdt_strerror.o \
diff --git a/lib/orc.c b/lib/orc.c
new file mode 100644
index 000000000000..980bd563b2cd
--- /dev/null
+++ b/lib/orc.c
@@ -0,0 +1,119 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/module.h>
+#include <linux/moduleloader.h>
+#include <linux/mutex.h>
+#include <linux/orc.h>
+#include <linux/sort.h>
+
+struct orc_entry *__orc_find(int *ip_table, struct orc_entry *u_table,
+ unsigned int num_entries, unsigned long ip)
+{
+ int *first = ip_table;
+ int *last = ip_table + num_entries - 1;
+ int *mid, *found = first;
+
+ if (!num_entries)
+ return NULL;
+
+ /*
+ * Do a binary range search to find the rightmost duplicate of a given
+ * starting address. Some entries are section terminators which are
+ * "weak" entries for ensuring there are no gaps. They should be
+ * ignored when they conflict with a real entry.
+ */
+ while (first <= last) {
+ mid = first + ((last - first) / 2);
+
+ if (orc_ip(mid) <= ip) {
+ found = mid;
+ first = mid + 1;
+ } else {
+ last = mid - 1;
+ }
+ }
+
+ return u_table + (found - ip_table);
+}
+
+#ifdef CONFIG_MODULES
+struct orc_entry *orc_module_find(unsigned long ip)
+{
+ struct module *mod;
+
+ mod = __module_address(ip);
+ if (!mod || !mod->orc_unwind || !mod->orc_unwind_ip)
+ return NULL;
+ return __orc_find(mod->orc_unwind_ip, mod->orc_unwind,
+ mod->num_orcs, ip);
+}
+
+static DEFINE_MUTEX(sort_mutex);
+static int *cur_orc_ip_table;
+static struct orc_entry *cur_orc_table;
+
+static void orc_sort_swap(void *_a, void *_b, int size)
+{
+ struct orc_entry *orc_a, *orc_b;
+ int *a = _a, *b = _b, tmp;
+ int delta = _b - _a;
+
+ /* Swap the .orc_unwind_ip entries: */
+ tmp = *a;
+ *a = *b + delta;
+ *b = tmp - delta;
+
+ /* Swap the corresponding .orc_unwind entries: */
+ orc_a = cur_orc_table + (a - cur_orc_ip_table);
+ orc_b = cur_orc_table + (b - cur_orc_ip_table);
+ swap(*orc_a, *orc_b);
+}
+
+static int orc_sort_cmp(const void *_a, const void *_b)
+{
+ struct orc_entry *orc_a;
+ const int *a = _a, *b = _b;
+ unsigned long a_val = orc_ip(a);
+ unsigned long b_val = orc_ip(b);
+
+ if (a_val > b_val)
+ return 1;
+ if (a_val < b_val)
+ return -1;
+
+ /*
+ * The "weak" section terminator entries need to always be first
+ * to ensure the lookup code skips them in favor of real entries.
+ * These terminator entries exist to handle any gaps created by
+ * whitelisted .o files which didn't get objtool generation.
+ */
+ orc_a = cur_orc_table + (a - cur_orc_ip_table);
+ return orc_a->type == ORC_TYPE_UNDEFINED ? -1 : 1;
+}
+
+void unwind_module_init(struct module *mod, void *_orc_ip, size_t orc_ip_size,
+ void *_orc, size_t orc_size)
+{
+ int *orc_ip = _orc_ip;
+ struct orc_entry *orc = _orc;
+ unsigned int num_entries = orc_ip_size / sizeof(int);
+
+ WARN_ON_ONCE(orc_ip_size % sizeof(int) != 0 ||
+ orc_size % sizeof(*orc) != 0 ||
+ num_entries != orc_size / sizeof(*orc));
+
+ /*
+ * The 'cur_orc_*' globals allow the orc_sort_swap() callback to
+ * associate an .orc_unwind_ip table entry with its corresponding
+ * .orc_unwind entry so they can both be swapped.
+ */
+ mutex_lock(&sort_mutex);
+ cur_orc_ip_table = orc_ip;
+ cur_orc_table = orc;
+ sort(orc_ip, num_entries, sizeof(int), orc_sort_cmp, orc_sort_swap);
+ mutex_unlock(&sort_mutex);
+
+ mod->orc_unwind_ip = orc_ip;
+ mod->orc_unwind = orc;
+ mod->num_orcs = num_entries;
+}
+#endif
--
2.55.0
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