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-rw-r--r--arch/x86/include/asm/jump_label.h79
-rw-r--r--arch/x86/kernel/jump_label.c81
-rw-r--r--arch/x86/realmode/Makefile1
-rw-r--r--include/linux/compiler.h22
-rw-r--r--include/linux/instrumentation.h20
-rw-r--r--include/linux/jump_label.h16
-rw-r--r--kernel/jump_label.c12
-rw-r--r--scripts/Makefile.build5
-rw-r--r--tools/objtool/arch/x86/decode.c2
-rw-r--r--tools/objtool/arch/x86/include/arch/special.h1
-rw-r--r--tools/objtool/check.c38
-rw-r--r--tools/objtool/elf.c110
-rw-r--r--tools/objtool/include/objtool/elf.h18
-rw-r--r--tools/objtool/include/objtool/objtool.h3
-rw-r--r--tools/objtool/include/objtool/special.h1
-rw-r--r--tools/objtool/special.c14
16 files changed, 268 insertions, 155 deletions
diff --git a/arch/x86/include/asm/jump_label.h b/arch/x86/include/asm/jump_label.h
index 610a05374c02..0449b125d27f 100644
--- a/arch/x86/include/asm/jump_label.h
+++ b/arch/x86/include/asm/jump_label.h
@@ -4,8 +4,6 @@
#define HAVE_JUMP_LABEL_BATCH
-#define JUMP_LABEL_NOP_SIZE 5
-
#include <asm/asm.h>
#include <asm/nops.h>
@@ -14,15 +12,35 @@
#include <linux/stringify.h>
#include <linux/types.h>
+#define JUMP_TABLE_ENTRY \
+ ".pushsection __jump_table, \"aw\" \n\t" \
+ _ASM_ALIGN "\n\t" \
+ ".long 1b - . \n\t" \
+ ".long %l[l_yes] - . \n\t" \
+ _ASM_PTR "%c0 + %c1 - .\n\t" \
+ ".popsection \n\t"
+
+#ifdef CONFIG_STACK_VALIDATION
+
+static __always_inline bool arch_static_branch(struct static_key *key, bool branch)
+{
+ asm_volatile_goto("1:"
+ "jmp %l[l_yes] # objtool NOPs this \n\t"
+ JUMP_TABLE_ENTRY
+ : : "i" (key), "i" (2 | branch) : : l_yes);
+
+ return false;
+l_yes:
+ return true;
+}
+
+#else
+
static __always_inline bool arch_static_branch(struct static_key * const key, const bool branch)
{
asm_volatile_goto("1:"
".byte " __stringify(BYTES_NOP5) "\n\t"
- ".pushsection __jump_table, \"aw\" \n\t"
- _ASM_ALIGN "\n\t"
- ".long 1b - ., %l[l_yes] - . \n\t"
- _ASM_PTR "%c0 + %c1 - .\n\t"
- ".popsection \n\t"
+ JUMP_TABLE_ENTRY
: : "i" (key), "i" (branch) : : l_yes);
return false;
@@ -30,16 +48,13 @@ l_yes:
return true;
}
+#endif /* STACK_VALIDATION */
+
static __always_inline bool arch_static_branch_jump(struct static_key * const key, const bool branch)
{
asm_volatile_goto("1:"
- ".byte 0xe9\n\t .long %l[l_yes] - 2f\n\t"
- "2:\n\t"
- ".pushsection __jump_table, \"aw\" \n\t"
- _ASM_ALIGN "\n\t"
- ".long 1b - ., %l[l_yes] - . \n\t"
- _ASM_PTR "%c0 + %c1 - .\n\t"
- ".popsection \n\t"
+ "jmp %l[l_yes]\n\t"
+ JUMP_TABLE_ENTRY
: : "i" (key), "i" (branch) : : l_yes);
return false;
@@ -47,41 +62,7 @@ l_yes:
return true;
}
-#else /* __ASSEMBLY__ */
-
-.macro STATIC_JUMP_IF_TRUE target, key, def
-.Lstatic_jump_\@:
- .if \def
- /* Equivalent to "jmp.d32 \target" */
- .byte 0xe9
- .long \target - .Lstatic_jump_after_\@
-.Lstatic_jump_after_\@:
- .else
- .byte BYTES_NOP5
- .endif
- .pushsection __jump_table, "aw"
- _ASM_ALIGN
- .long .Lstatic_jump_\@ - ., \target - .
- _ASM_PTR \key - .
- .popsection
-.endm
-
-.macro STATIC_JUMP_IF_FALSE target, key, def
-.Lstatic_jump_\@:
- .if \def
- .byte BYTES_NOP5
- .else
- /* Equivalent to "jmp.d32 \target" */
- .byte 0xe9
- .long \target - .Lstatic_jump_after_\@
-.Lstatic_jump_after_\@:
- .endif
- .pushsection __jump_table, "aw"
- _ASM_ALIGN
- .long .Lstatic_jump_\@ - ., \target - .
- _ASM_PTR \key + 1 - .
- .popsection
-.endm
+extern int arch_jump_entry_size(struct jump_entry *entry);
#endif /* __ASSEMBLY__ */
diff --git a/arch/x86/kernel/jump_label.c b/arch/x86/kernel/jump_label.c
index 6a2eb62c85e6..674906fad43b 100644
--- a/arch/x86/kernel/jump_label.c
+++ b/arch/x86/kernel/jump_label.c
@@ -15,50 +15,75 @@
#include <asm/kprobes.h>
#include <asm/alternative.h>
#include <asm/text-patching.h>
+#include <asm/insn.h>
-static void bug_at(const void *ip, int line)
+int arch_jump_entry_size(struct jump_entry *entry)
{
- /*
- * The location is not an op that we were expecting.
- * Something went wrong. Crash the box, as something could be
- * corrupting the kernel.
- */
- pr_crit("jump_label: Fatal kernel bug, unexpected op at %pS [%p] (%5ph) %d\n", ip, ip, ip, line);
- BUG();
+ struct insn insn = {};
+
+ insn_decode_kernel(&insn, (void *)jump_entry_code(entry));
+ BUG_ON(insn.length != 2 && insn.length != 5);
+
+ return insn.length;
}
-static const void *
-__jump_label_set_jump_code(struct jump_entry *entry, enum jump_label_type type)
+struct jump_label_patch {
+ const void *code;
+ int size;
+};
+
+static struct jump_label_patch
+__jump_label_patch(struct jump_entry *entry, enum jump_label_type type)
{
- const void *expect, *code;
+ const void *expect, *code, *nop;
const void *addr, *dest;
- int line;
+ int size;
addr = (void *)jump_entry_code(entry);
dest = (void *)jump_entry_target(entry);
- code = text_gen_insn(JMP32_INSN_OPCODE, addr, dest);
+ size = arch_jump_entry_size(entry);
+ switch (size) {
+ case JMP8_INSN_SIZE:
+ code = text_gen_insn(JMP8_INSN_OPCODE, addr, dest);
+ nop = x86_nops[size];
+ break;
- if (type == JUMP_LABEL_JMP) {
- expect = x86_nops[5]; line = __LINE__;
- } else {
- expect = code; line = __LINE__;
+ case JMP32_INSN_SIZE:
+ code = text_gen_insn(JMP32_INSN_OPCODE, addr, dest);
+ nop = x86_nops[size];
+ break;
+
+ default: BUG();
}
- if (memcmp(addr, expect, JUMP_LABEL_NOP_SIZE))
- bug_at(addr, line);
+ if (type == JUMP_LABEL_JMP)
+ expect = nop;
+ else
+ expect = code;
+
+ if (memcmp(addr, expect, size)) {
+ /*
+ * The location is not an op that we were expecting.
+ * Something went wrong. Crash the box, as something could be
+ * corrupting the kernel.
+ */
+ pr_crit("jump_label: Fatal kernel bug, unexpected op at %pS [%p] (%5ph != %5ph)) size:%d type:%d\n",
+ addr, addr, addr, expect, size, type);
+ BUG();
+ }
if (type == JUMP_LABEL_NOP)
- code = x86_nops[5];
+ code = nop;
- return code;
+ return (struct jump_label_patch){.code = code, .size = size};
}
static inline void __jump_label_transform(struct jump_entry *entry,
enum jump_label_type type,
int init)
{
- const void *opcode = __jump_label_set_jump_code(entry, type);
+ const struct jump_label_patch jlp = __jump_label_patch(entry, type);
/*
* As long as only a single processor is running and the code is still
@@ -72,12 +97,11 @@ static inline void __jump_label_transform(struct jump_entry *entry,
* always nop being the 'currently valid' instruction
*/
if (init || system_state == SYSTEM_BOOTING) {
- text_poke_early((void *)jump_entry_code(entry), opcode,
- JUMP_LABEL_NOP_SIZE);
+ text_poke_early((void *)jump_entry_code(entry), jlp.code, jlp.size);
return;
}
- text_poke_bp((void *)jump_entry_code(entry), opcode, JUMP_LABEL_NOP_SIZE, NULL);
+ text_poke_bp((void *)jump_entry_code(entry), jlp.code, jlp.size, NULL);
}
static void __ref jump_label_transform(struct jump_entry *entry,
@@ -98,7 +122,7 @@ void arch_jump_label_transform(struct jump_entry *entry,
bool arch_jump_label_transform_queue(struct jump_entry *entry,
enum jump_label_type type)
{
- const void *opcode;
+ struct jump_label_patch jlp;
if (system_state == SYSTEM_BOOTING) {
/*
@@ -109,9 +133,8 @@ bool arch_jump_label_transform_queue(struct jump_entry *entry,
}
mutex_lock(&text_mutex);
- opcode = __jump_label_set_jump_code(entry, type);
- text_poke_queue((void *)jump_entry_code(entry),
- opcode, JUMP_LABEL_NOP_SIZE, NULL);
+ jlp = __jump_label_patch(entry, type);
+ text_poke_queue((void *)jump_entry_code(entry), jlp.code, jlp.size, NULL);
mutex_unlock(&text_mutex);
return true;
}
diff --git a/arch/x86/realmode/Makefile b/arch/x86/realmode/Makefile
index 6b1f3a4eeb44..a0b491ae2de8 100644
--- a/arch/x86/realmode/Makefile
+++ b/arch/x86/realmode/Makefile
@@ -10,7 +10,6 @@
# Sanitizer runtimes are unavailable and cannot be linked here.
KASAN_SANITIZE := n
KCSAN_SANITIZE := n
-OBJECT_FILES_NON_STANDARD := y
subdir- := rm
diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index df5b405e6305..77047904cf70 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -115,18 +115,24 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val,
* The __COUNTER__ based labels are a hack to make each instance of the macros
* unique, to convince GCC not to merge duplicate inline asm statements.
*/
-#define annotate_reachable() ({ \
- asm volatile("%c0:\n\t" \
+#define __stringify_label(n) #n
+
+#define __annotate_reachable(c) ({ \
+ asm volatile(__stringify_label(c) ":\n\t" \
".pushsection .discard.reachable\n\t" \
- ".long %c0b - .\n\t" \
- ".popsection\n\t" : : "i" (__COUNTER__)); \
+ ".long " __stringify_label(c) "b - .\n\t" \
+ ".popsection\n\t"); \
})
-#define annotate_unreachable() ({ \
- asm volatile("%c0:\n\t" \
+#define annotate_reachable() __annotate_reachable(__COUNTER__)
+
+#define __annotate_unreachable(c) ({ \
+ asm volatile(__stringify_label(c) ":\n\t" \
".pushsection .discard.unreachable\n\t" \
- ".long %c0b - .\n\t" \
- ".popsection\n\t" : : "i" (__COUNTER__)); \
+ ".long " __stringify_label(c) "b - .\n\t" \
+ ".popsection\n\t"); \
})
+#define annotate_unreachable() __annotate_unreachable(__COUNTER__)
+
#define ASM_UNREACHABLE \
"999:\n\t" \
".pushsection .discard.unreachable\n\t" \
diff --git a/include/linux/instrumentation.h b/include/linux/instrumentation.h
index 93e2ad67fc10..fa2cd8c63dcc 100644
--- a/include/linux/instrumentation.h
+++ b/include/linux/instrumentation.h
@@ -4,13 +4,16 @@
#if defined(CONFIG_DEBUG_ENTRY) && defined(CONFIG_STACK_VALIDATION)
+#include <linux/stringify.h>
+
/* Begin/end of an instrumentation safe region */
-#define instrumentation_begin() ({ \
- asm volatile("%c0: nop\n\t" \
+#define __instrumentation_begin(c) ({ \
+ asm volatile(__stringify(c) ": nop\n\t" \
".pushsection .discard.instr_begin\n\t" \
- ".long %c0b - .\n\t" \
- ".popsection\n\t" : : "i" (__COUNTER__)); \
+ ".long " __stringify(c) "b - .\n\t" \
+ ".popsection\n\t"); \
})
+#define instrumentation_begin() __instrumentation_begin(__COUNTER__)
/*
* Because instrumentation_{begin,end}() can nest, objtool validation considers
@@ -43,12 +46,13 @@
* To avoid this, have _end() be a NOP instruction, this ensures it will be
* part of the condition block and does not escape.
*/
-#define instrumentation_end() ({ \
- asm volatile("%c0: nop\n\t" \
+#define __instrumentation_end(c) ({ \
+ asm volatile(__stringify(c) ": nop\n\t" \
".pushsection .discard.instr_end\n\t" \
- ".long %c0b - .\n\t" \
- ".popsection\n\t" : : "i" (__COUNTER__)); \
+ ".long " __stringify(c) "b - .\n\t" \
+ ".popsection\n\t"); \
})
+#define instrumentation_end() __instrumentation_end(__COUNTER__)
#else
# define instrumentation_begin() do { } while(0)
# define instrumentation_end() do { } while(0)
diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h
index 05f5554d860f..48b9b2a82767 100644
--- a/include/linux/jump_label.h
+++ b/include/linux/jump_label.h
@@ -171,9 +171,21 @@ static inline bool jump_entry_is_init(const struct jump_entry *entry)
return (unsigned long)entry->key & 2UL;
}
-static inline void jump_entry_set_init(struct jump_entry *entry)
+static inline void jump_entry_set_init(struct jump_entry *entry, bool set)
{
- entry->key |= 2;
+ if (set)
+ entry->key |= 2;
+ else
+ entry->key &= ~2;
+}
+
+static inline int jump_entry_size(struct jump_entry *entry)
+{
+#ifdef JUMP_LABEL_NOP_SIZE
+ return JUMP_LABEL_NOP_SIZE;
+#else
+ return arch_jump_entry_size(entry);
+#endif
}
#endif
diff --git a/kernel/jump_label.c b/kernel/jump_label.c
index ba39fbb1f8e7..bdb0681bece8 100644
--- a/kernel/jump_label.c
+++ b/kernel/jump_label.c
@@ -309,7 +309,7 @@ EXPORT_SYMBOL_GPL(jump_label_rate_limit);
static int addr_conflict(struct jump_entry *entry, void *start, void *end)
{
if (jump_entry_code(entry) <= (unsigned long)end &&
- jump_entry_code(entry) + JUMP_LABEL_NOP_SIZE > (unsigned long)start)
+ jump_entry_code(entry) + jump_entry_size(entry) > (unsigned long)start)
return 1;
return 0;
@@ -483,13 +483,14 @@ void __init jump_label_init(void)
for (iter = iter_start; iter < iter_stop; iter++) {
struct static_key *iterk;
+ bool in_init;
/* rewrite NOPs */
if (jump_label_type(iter) == JUMP_LABEL_NOP)
arch_jump_label_transform_static(iter, JUMP_LABEL_NOP);
- if (init_section_contains((void *)jump_entry_code(iter), 1))
- jump_entry_set_init(iter);
+ in_init = init_section_contains((void *)jump_entry_code(iter), 1);
+ jump_entry_set_init(iter, in_init);
iterk = jump_entry_key(iter);
if (iterk == key)
@@ -634,9 +635,10 @@ static int jump_label_add_module(struct module *mod)
for (iter = iter_start; iter < iter_stop; iter++) {
struct static_key *iterk;
+ bool in_init;
- if (within_module_init(jump_entry_code(iter), mod))
- jump_entry_set_init(iter);
+ in_init = within_module_init(jump_entry_code(iter), mod);
+ jump_entry_set_init(iter, in_init);
iterk = jump_entry_key(iter);
if (iterk == key)
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 949f723efe53..34d257653fb4 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -268,7 +268,8 @@ define rule_as_o_S
endef
# Built-in and composite module parts
-$(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_dep) FORCE
+.SECONDEXPANSION:
+$(obj)/%.o: $(src)/%.c $(recordmcount_source) $$(objtool_dep) FORCE
$(call if_changed_rule,cc_o_c)
$(call cmd,force_checksrc)
@@ -349,7 +350,7 @@ cmd_modversions_S = \
fi
endif
-$(obj)/%.o: $(src)/%.S $(objtool_dep) FORCE
+$(obj)/%.o: $(src)/%.S $$(objtool_dep) FORCE
$(call if_changed_rule,as_o_S)
targets += $(filter-out $(subdir-builtin), $(real-obj-y))
diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index 523aa4157f80..bc821056aba9 100644
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -684,7 +684,7 @@ static int elf_add_alternative(struct elf *elf,
sec = find_section_by_name(elf, ".altinstructions");
if (!sec) {
sec = elf_create_section(elf, ".altinstructions",
- SHF_WRITE, size, 0);
+ SHF_ALLOC, size, 0);
if (!sec) {
WARN_ELF("elf_create_section");
diff --git a/tools/objtool/arch/x86/include/arch/special.h b/tools/objtool/arch/x86/include/arch/special.h
index 14271cca0c74..f2918f789a0a 100644
--- a/tools/objtool/arch/x86/include/arch/special.h
+++ b/tools/objtool/arch/x86/include/arch/special.h
@@ -9,6 +9,7 @@
#define JUMP_ENTRY_SIZE 16
#define JUMP_ORIG_OFFSET 0
#define JUMP_NEW_OFFSET 4
+#define JUMP_KEY_OFFSET 8
#define ALT_ENTRY_SIZE 12
#define ALT_ORIG_OFFSET 0
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 9ed1a4cd00dc..e5947fbb9e7a 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1225,15 +1225,41 @@ static int handle_jump_alt(struct objtool_file *file,
struct instruction *orig_insn,
struct instruction **new_insn)
{
- if (orig_insn->type == INSN_NOP)
- return 0;
+ if (orig_insn->type != INSN_JUMP_UNCONDITIONAL &&
+ orig_insn->type != INSN_NOP) {
- if (orig_insn->type != INSN_JUMP_UNCONDITIONAL) {
WARN_FUNC("unsupported instruction at jump label",
orig_insn->sec, orig_insn->offset);
return -1;
}
+ if (special_alt->key_addend & 2) {
+ struct reloc *reloc = insn_reloc(file, orig_insn);
+
+ if (reloc) {
+ reloc->type = R_NONE;
+ elf_write_reloc(file->elf, reloc);
+ }
+ elf_write_insn(file->elf, orig_insn->sec,
+ orig_insn->offset, orig_insn->len,
+ arch_nop_insn(orig_insn->len));
+ orig_insn->type = INSN_NOP;
+ }
+
+ if (orig_insn->type == INSN_NOP) {
+ if (orig_insn->len == 2)
+ file->jl_nop_short++;
+ else
+ file->jl_nop_long++;
+
+ return 0;
+ }
+
+ if (orig_insn->len == 2)
+ file->jl_short++;
+ else
+ file->jl_long++;
+
*new_insn = list_next_entry(orig_insn, list);
return 0;
}
@@ -1314,6 +1340,12 @@ static int add_special_section_alts(struct objtool_file *file)
free(special_alt);
}
+ if (stats) {
+ printf("jl\\\tNOP\tJMP\n");
+ printf("short:\t%ld\t%ld\n", file->jl_nop_short, file->jl_short);
+ printf("long:\t%ld\t%ld\n", file->jl_nop_long, file->jl_long);
+ }
+
out:
return ret;
}
diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index 41bca1d13d8e..8676c7598728 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -9,6 +9,7 @@
#include <sys/types.h>
#include <sys/stat.h>
+#include <sys/mman.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
@@ -27,21 +28,27 @@ static inline u32 str_hash(const char *str)
return jhash(str, strlen(str), 0);
}
-static inline int elf_hash_bits(void)
-{
- return vmlinux ? ELF_HASH_BITS : 16;
-}
+#define __elf_table(name) (elf->name##_hash)
+#define __elf_bits(name) (elf->name##_bits)
-#define elf_hash_add(hashtable, node, key) \
- hlist_add_head(node, &hashtable[hash_min(key, elf_hash_bits())])
+#define elf_hash_add(name, node, key) \
+ hlist_add_head(node, &__elf_table(name)[hash_min(key, __elf_bits(name))])
-static void elf_hash_init(struct hlist_head *table)
-{
- __hash_init(table, 1U << elf_hash_bits());
-}
+#define elf_hash_for_each_possible(name, obj, member, key) \
+ hlist_for_each_entry(obj, &__elf_table(name)[hash_min(key, __elf_bits(name))], member)
-#define elf_hash_for_each_possible(name, obj, member, key) \
- hlist_for_each_entry(obj, &name[hash_min(key, elf_hash_bits())], member)
+#define elf_alloc_hash(name, size) \
+({ \
+ __elf_bits(name) = max(10, ilog2(size)); \
+ __elf_table(name) = mmap(NULL, sizeof(struct hlist_head) << __elf_bits(name), \
+ PROT_READ|PROT_WRITE, \
+ MAP_PRIVATE|MAP_ANON, -1, 0); \
+ if (__elf_table(name) == (void *)-1L) { \
+ WARN("mmap fail " #name); \
+ __elf_table(name) = NULL; \
+ } \
+ __elf_table(name); \
+})
static bool symbol_to_offset(struct rb_node *a, const struct rb_node *b)
{
@@ -80,9 +87,10 @@ struct section *find_section_by_name(const struct elf *elf, const char *name)
{
struct section *sec;
- elf_hash_for_each_possible(elf->section_name_hash, sec, name_hash, str_hash(name))
+ elf_hash_for_each_possible(section_name, sec, name_hash, str_hash(name)) {
if (!strcmp(sec->name, name))
return sec;
+ }
return NULL;
}
@@ -92,9 +100,10 @@ static struct section *find_section_by_index(struct elf *elf,
{
struct section *sec;
- elf_hash_for_each_possible(elf->section_hash, sec, hash, idx)
+ elf_hash_for_each_possible(section, sec, hash, idx) {
if (sec->idx == idx)
return sec;
+ }
return NULL;
}
@@ -103,9 +112,10 @@ static struct symbol *find_symbol_by_index(struct elf *elf, unsigned int idx)
{
struct symbol *sym;
- elf_hash_for_each_possible(elf->symbol_hash, sym, hash, idx)
+ elf_hash_for_each_possible(symbol, sym, hash, idx) {
if (sym->idx == idx)
return sym;
+ }
return NULL;
}
@@ -170,9 +180,10 @@ struct symbol *find_symbol_by_name(const struct elf *elf, const char *name)
{
struct symbol *sym;
- elf_hash_for_each_possible(elf->symbol_name_hash, sym, name_hash, str_hash(name))
+ elf_hash_for_each_possible(symbol_name, sym, name_hash, str_hash(name)) {
if (!strcmp(sym->name, name))
return sym;
+ }
return NULL;
}
@@ -189,8 +200,8 @@ struct reloc *find_reloc_by_dest_range(const struct elf *elf, struct section *se
sec = sec->reloc;
for_offset_range(o, offset, offset + len) {
- elf_hash_for_each_possible(elf->reloc_hash, reloc, hash,
- sec_offset_hash(sec, o)) {
+ elf_hash_for_each_possible(reloc, reloc, hash,
+ sec_offset_hash(sec, o)) {
if (reloc->sec != sec)
continue;
@@ -228,6 +239,10 @@ static int read_sections(struct elf *elf)
return -1;
}
+ if (!elf_alloc_hash(section, sections_nr) ||
+ !elf_alloc_hash(section_name, sections_nr))
+ return -1;
+
for (i = 0; i < sections_nr; i++) {
sec = malloc(sizeof(*sec));
if (!sec) {
@@ -273,13 +288,18 @@ static int read_sections(struct elf *elf)
}
sec->len = sec->sh.sh_size;
+ if (sec->sh.sh_flags & SHF_EXECINSTR)
+ elf->text_size += sec->len;
+
list_add_tail(&sec->list, &elf->sections);
- elf_hash_add(elf->section_hash, &sec->hash, sec->idx);
- elf_hash_add(elf->section_name_hash, &sec->name_hash, str_hash(sec->name));
+ elf_hash_add(section, &sec->hash, sec->idx);
+ elf_hash_add(section_name, &sec->name_hash, str_hash(sec->name));
}
- if (stats)
+ if (stats) {
printf("nr_sections: %lu\n", (unsigned long)sections_nr);
+ printf("section_bits: %d\n", elf->section_bits);
+ }
/* sanity check, one more call to elf_nextscn() should return NULL */
if (elf_nextscn(elf->elf, s)) {
@@ -308,8 +328,8 @@ static void elf_add_symbol(struct elf *elf, struct symbol *sym)
else
entry = &sym->sec->symbol_list;
list_add(&sym->list, entry);
- elf_hash_add(elf->symbol_hash, &sym->hash, sym->idx);
- elf_hash_add(elf->symbol_name_hash, &sym->name_hash, str_hash(sym->name));
+ elf_hash_add(symbol, &sym->hash, sym->idx);
+ elf_hash_add(symbol_name, &sym->name_hash, str_hash(sym->name));
/*
* Don't store empty STT_NOTYPE symbols in the rbtree. They
@@ -329,19 +349,25 @@ static int read_symbols(struct elf *elf)
Elf32_Word shndx;
symtab = find_section_by_name(elf, ".symtab");
- if (!symtab) {
+ if (symtab) {
+ symtab_shndx = find_section_by_name(elf, ".symtab_shndx");
+ if (symtab_shndx)
+ shndx_data = symtab_shndx->data;
+
+ symbols_nr = symtab->sh.sh_size / symtab->sh.sh_entsize;
+ } else {
/*
* A missing symbol table is actually possible if it's an empty
- * .o file. This can happen for thunk_64.o.
+ * .o file. This can happen for thunk_64.o. Make sure to at
+ * least allocate the symbol hash tables so we can do symbol
+ * lookups without crashing.
*/
- return 0;
+ symbols_nr = 0;
}
- symtab_shndx = find_section_by_name(elf, ".symtab_shndx");
- if (symtab_shndx)
- shndx_data = symtab_shndx->data;
-
- symbols_nr = symtab->sh.sh_size / symtab->sh.sh_entsize;
+ if (!elf_alloc_hash(symbol, symbols_nr) ||
+ !elf_alloc_hash(symbol_name, symbols_nr))
+ return -1;
for (i = 0; i < symbols_nr; i++) {
sym = malloc(sizeof(*sym));
@@ -389,8 +415,10 @@ static int read_symbols(struct elf *elf)
elf_add_symbol(elf, sym);
}
- if (stats)
+ if (stats) {
printf("nr_symbols: %lu\n", (unsigned long)symbols_nr);
+ printf("symbol_bits: %d\n", elf->symbol_bits);
+ }
/* Create parent/child links for any cold subfunctions */
list_for_each_entry(sec, &elf->sections, list) {
@@ -479,7 +507,7 @@ int elf_add_reloc(struct elf *elf, struct section *sec, unsigned long offset,
reloc->addend = addend;
list_add_tail(&reloc->list, &sec->reloc->reloc_list);
- elf_hash_add(elf->reloc_hash, &reloc->hash, reloc_hash(reloc));
+ elf_hash_add(reloc, &reloc->hash, reloc_hash(reloc));
sec->reloc->changed = true;
@@ -556,6 +584,9 @@ static int read_relocs(struct elf *elf)
unsigned int symndx;
unsigned long nr_reloc, max_reloc = 0, tot_reloc = 0;
+ if (!elf_alloc_hash(reloc, elf->text_size / 16))
+ return -1;
+
list_for_each_entry(sec, &elf->sections, list) {
if ((sec->sh.sh_type != SHT_RELA) &&
(sec->sh.sh_type != SHT_REL))
@@ -600,7 +631,7 @@ static int read_relocs(struct elf *elf)
}
list_add_tail(&reloc->list, &sec->reloc_list);
- elf_hash_add(elf->reloc_hash, &reloc->hash, reloc_hash(reloc));
+ elf_hash_add(reloc, &reloc->hash, reloc_hash(reloc));
nr_reloc++;
}
@@ -611,6 +642,7 @@ static int read_relocs(struct elf *elf)
if (stats) {
printf("max_reloc: %lu\n", max_reloc);
printf("tot_reloc: %lu\n", tot_reloc);
+ printf("reloc_bits: %d\n", elf->reloc_bits);
}
return 0;
@@ -632,12 +664,6 @@ struct elf *elf_open_read(const char *name, int flags)
INIT_LIST_HEAD(&elf->sections);
- elf_hash_init(elf->symbol_hash);
- elf_hash_init(elf->symbol_name_hash);
- elf_hash_init(elf->section_hash);
- elf_hash_init(elf->section_name_hash);
- elf_hash_init(elf->reloc_hash);
-
elf->fd = open(name, flags);
if (elf->fd == -1) {
fprintf(stderr, "objtool: Can't open '%s': %s\n",
@@ -874,8 +900,8 @@ struct section *elf_create_section(struct elf *elf, const char *name,
return NULL;
list_add_tail(&sec->list, &elf->sections);
- elf_hash_add(elf->section_hash, &sec->hash, sec->idx);
- elf_hash_add(elf->section_name_hash, &sec->name_hash, str_hash(sec->name));
+ elf_hash_add(section, &sec->hash, sec->idx);
+ elf_hash_add(section_name, &sec->name_hash, str_hash(sec->name));
elf->changed = true;
diff --git a/tools/objtool/include/objtool/elf.h b/tools/objtool/include/objtool/elf.h
index 45e5ede363b0..e34395047530 100644
--- a/tools/objtool/include/objtool/elf.h
+++ b/tools/objtool/include/objtool/elf.h
@@ -83,12 +83,20 @@ struct elf {
int fd;
bool changed;
char *name;
+ unsigned int text_size;
struct list_head sections;
- DECLARE_HASHTABLE(symbol_hash, ELF_HASH_BITS);
- DECLARE_HASHTABLE(symbol_name_hash, ELF_HASH_BITS);
- DECLARE_HASHTABLE(section_hash, ELF_HASH_BITS);
- DECLARE_HASHTABLE(section_name_hash, ELF_HASH_BITS);
- DECLARE_HASHTABLE(reloc_hash, ELF_HASH_BITS);
+
+ int symbol_bits;
+ int symbol_name_bits;
+ int section_bits;
+ int section_name_bits;
+ int reloc_bits;
+
+ struct hlist_head *symbol_hash;
+ struct hlist_head *symbol_name_hash;
+ struct hlist_head *section_hash;
+ struct hlist_head *section_name_hash;
+ struct hlist_head *reloc_hash;
};
#define OFFSET_STRIDE_BITS 4
diff --git a/tools/objtool/include/objtool/objtool.h b/tools/objtool/include/objtool/objtool.h
index e4084afb2304..24fa83634de4 100644
--- a/tools/objtool/include/objtool/objtool.h
+++ b/tools/objtool/include/objtool/objtool.h
@@ -22,6 +22,9 @@ struct objtool_file {
struct list_head static_call_list;
struct list_head mcount_loc_list;
bool ignore_unreachables, c_file, hints, rodata;
+
+ unsigned long jl_short, jl_long;
+ unsigned long jl_nop_short, jl_nop_long;
};
struct objtool_file *objtool_open_read(const char *_objname);
diff --git a/tools/objtool/include/objtool/special.h b/tools/objtool/include/objtool/special.h
index 8a09f4e9d480..dc4721e19002 100644
--- a/tools/objtool/include/objtool/special.h
+++ b/tools/objtool/include/objtool/special.h
@@ -27,6 +27,7 @@ struct special_alt {
unsigned long new_off;
unsigned int orig_len, new_len; /* group only */
+ u8 key_addend;
};
int special_get_alts(struct elf *elf, struct list_head *alts);
diff --git a/tools/objtool/special.c b/tools/objtool/special.c
index 07b21cfabf5c..bc925cf19e2d 100644
--- a/tools/objtool/special.c
+++ b/tools/objtool/special.c
@@ -23,6 +23,7 @@ struct special_entry {
unsigned char size, orig, new;
unsigned char orig_len, new_len; /* group only */
unsigned char feature; /* ALTERNATIVE macro CPU feature */
+ unsigned char key; /* jump_label key */
};
struct special_entry entries[] = {
@@ -42,6 +43,7 @@ struct special_entry entries[] = {
.size = JUMP_ENTRY_SIZE,
.orig = JUMP_ORIG_OFFSET,
.new = JUMP_NEW_OFFSET,
+ .key = JUMP_KEY_OFFSET,
},
{
.sec = "__ex_table",
@@ -122,6 +124,18 @@ static int get_alt_entry(struct elf *elf, struct special_entry *entry,
alt->new_off -= 0x7ffffff0;
}
+ if (entry->key) {
+ struct reloc *key_reloc;
+
+ key_reloc = find_reloc_by_dest(elf, sec, offset + entry->key);
+ if (!key_reloc) {
+ WARN_FUNC("can't find key reloc",
+ sec, offset + entry->key);
+ return -1;
+ }
+ alt->key_addend = key_reloc->addend;
+ }
+
return 0;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-30 17:08:08 +0100