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-rw-r--r--tools/objtool/check.c664
1 files changed, 504 insertions, 160 deletions
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index e5947fbb9e7a..add39902166d 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -5,6 +5,7 @@
#include <string.h>
#include <stdlib.h>
+#include <sys/mman.h>
#include <arch/elf.h>
#include <objtool/builtin.h>
@@ -26,7 +27,11 @@ struct alternative {
bool skip_orig;
};
-struct cfi_init_state initial_func_cfi;
+static unsigned long nr_cfi, nr_cfi_reused, nr_cfi_cache;
+
+static struct cfi_init_state initial_func_cfi;
+static struct cfi_state init_cfi;
+static struct cfi_state func_cfi;
struct instruction *find_insn(struct objtool_file *file,
struct section *sec, unsigned long offset)
@@ -173,6 +178,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func,
"rewind_stack_do_exit",
"kunit_try_catch_throw",
"xen_start_kernel",
+ "cpu_bringup_and_idle",
};
if (!func)
@@ -265,6 +271,78 @@ static void init_insn_state(struct insn_state *state, struct section *sec)
state->noinstr = sec->noinstr;
}
+static struct cfi_state *cfi_alloc(void)
+{
+ struct cfi_state *cfi = calloc(sizeof(struct cfi_state), 1);
+ if (!cfi) {
+ WARN("calloc failed");
+ exit(1);
+ }
+ nr_cfi++;
+ return cfi;
+}
+
+static int cfi_bits;
+static struct hlist_head *cfi_hash;
+
+static inline bool cficmp(struct cfi_state *cfi1, struct cfi_state *cfi2)
+{
+ return memcmp((void *)cfi1 + sizeof(cfi1->hash),
+ (void *)cfi2 + sizeof(cfi2->hash),
+ sizeof(struct cfi_state) - sizeof(struct hlist_node));
+}
+
+static inline u32 cfi_key(struct cfi_state *cfi)
+{
+ return jhash((void *)cfi + sizeof(cfi->hash),
+ sizeof(*cfi) - sizeof(cfi->hash), 0);
+}
+
+static struct cfi_state *cfi_hash_find_or_add(struct cfi_state *cfi)
+{
+ struct hlist_head *head = &cfi_hash[hash_min(cfi_key(cfi), cfi_bits)];
+ struct cfi_state *obj;
+
+ hlist_for_each_entry(obj, head, hash) {
+ if (!cficmp(cfi, obj)) {
+ nr_cfi_cache++;
+ return obj;
+ }
+ }
+
+ obj = cfi_alloc();
+ *obj = *cfi;
+ hlist_add_head(&obj->hash, head);
+
+ return obj;
+}
+
+static void cfi_hash_add(struct cfi_state *cfi)
+{
+ struct hlist_head *head = &cfi_hash[hash_min(cfi_key(cfi), cfi_bits)];
+
+ hlist_add_head(&cfi->hash, head);
+}
+
+static void *cfi_hash_alloc(unsigned long size)
+{
+ cfi_bits = max(10, ilog2(size));
+ cfi_hash = mmap(NULL, sizeof(struct hlist_head) << cfi_bits,
+ PROT_READ|PROT_WRITE,
+ MAP_PRIVATE|MAP_ANON, -1, 0);
+ if (cfi_hash == (void *)-1L) {
+ WARN("mmap fail cfi_hash");
+ cfi_hash = NULL;
+ } else if (stats) {
+ printf("cfi_bits: %d\n", cfi_bits);
+ }
+
+ return cfi_hash;
+}
+
+static unsigned long nr_insns;
+static unsigned long nr_insns_visited;
+
/*
* Call the arch-specific instruction decoder for all the instructions and add
* them to the global instruction list.
@@ -275,7 +353,6 @@ static int decode_instructions(struct objtool_file *file)
struct symbol *func;
unsigned long offset;
struct instruction *insn;
- unsigned long nr_insns = 0;
int ret;
for_each_sec(file, sec) {
@@ -292,7 +369,7 @@ static int decode_instructions(struct objtool_file *file)
!strcmp(sec->name, ".entry.text"))
sec->noinstr = true;
- for (offset = 0; offset < sec->len; offset += insn->len) {
+ for (offset = 0; offset < sec->sh.sh_size; offset += insn->len) {
insn = malloc(sizeof(*insn));
if (!insn) {
WARN("malloc failed");
@@ -301,13 +378,12 @@ static int decode_instructions(struct objtool_file *file)
memset(insn, 0, sizeof(*insn));
INIT_LIST_HEAD(&insn->alts);
INIT_LIST_HEAD(&insn->stack_ops);
- init_cfi_state(&insn->cfi);
insn->sec = sec;
insn->offset = offset;
- ret = arch_decode_instruction(file->elf, sec, offset,
- sec->len - offset,
+ ret = arch_decode_instruction(file, sec, offset,
+ sec->sh.sh_size - offset,
&insn->len, &insn->type,
&insn->immediate,
&insn->stack_ops);
@@ -344,14 +420,90 @@ err:
return ret;
}
+/*
+ * Read the pv_ops[] .data table to find the static initialized values.
+ */
+static int add_pv_ops(struct objtool_file *file, const char *symname)
+{
+ struct symbol *sym, *func;
+ unsigned long off, end;
+ struct reloc *rel;
+ int idx;
+
+ sym = find_symbol_by_name(file->elf, symname);
+ if (!sym)
+ return 0;
+
+ off = sym->offset;
+ end = off + sym->len;
+ for (;;) {
+ rel = find_reloc_by_dest_range(file->elf, sym->sec, off, end - off);
+ if (!rel)
+ break;
+
+ func = rel->sym;
+ if (func->type == STT_SECTION)
+ func = find_symbol_by_offset(rel->sym->sec, rel->addend);
+
+ idx = (rel->offset - sym->offset) / sizeof(unsigned long);
+
+ objtool_pv_add(file, idx, func);
+
+ off = rel->offset + 1;
+ if (off > end)
+ break;
+ }
+
+ return 0;
+}
+
+/*
+ * Allocate and initialize file->pv_ops[].
+ */
+static int init_pv_ops(struct objtool_file *file)
+{
+ static const char *pv_ops_tables[] = {
+ "pv_ops",
+ "xen_cpu_ops",
+ "xen_irq_ops",
+ "xen_mmu_ops",
+ NULL,
+ };
+ const char *pv_ops;
+ struct symbol *sym;
+ int idx, nr;
+
+ if (!noinstr)
+ return 0;
+
+ file->pv_ops = NULL;
+
+ sym = find_symbol_by_name(file->elf, "pv_ops");
+ if (!sym)
+ return 0;
+
+ nr = sym->len / sizeof(unsigned long);
+ file->pv_ops = calloc(sizeof(struct pv_state), nr);
+ if (!file->pv_ops)
+ return -1;
+
+ for (idx = 0; idx < nr; idx++)
+ INIT_LIST_HEAD(&file->pv_ops[idx].targets);
+
+ for (idx = 0; (pv_ops = pv_ops_tables[idx]); idx++)
+ add_pv_ops(file, pv_ops);
+
+ return 0;
+}
+
static struct instruction *find_last_insn(struct objtool_file *file,
struct section *sec)
{
struct instruction *insn = NULL;
unsigned int offset;
- unsigned int end = (sec->len > 10) ? sec->len - 10 : 0;
+ unsigned int end = (sec->sh.sh_size > 10) ? sec->sh.sh_size - 10 : 0;
- for (offset = sec->len - 1; offset >= end && !insn; offset--)
+ for (offset = sec->sh.sh_size - 1; offset >= end && !insn; offset--)
insn = find_insn(file, sec, offset);
return insn;
@@ -389,7 +541,7 @@ static int add_dead_ends(struct objtool_file *file)
insn = find_insn(file, reloc->sym->sec, reloc->addend);
if (insn)
insn = list_prev_entry(insn, list);
- else if (reloc->addend == reloc->sym->sec->len) {
+ else if (reloc->addend == reloc->sym->sec->sh.sh_size) {
insn = find_last_insn(file, reloc->sym->sec);
if (!insn) {
WARN("can't find unreachable insn at %s+0x%x",
@@ -424,7 +576,7 @@ reachable:
insn = find_insn(file, reloc->sym->sec, reloc->addend);
if (insn)
insn = list_prev_entry(insn, list);
- else if (reloc->addend == reloc->sym->sec->len) {
+ else if (reloc->addend == reloc->sym->sec->sh.sh_size) {
insn = find_last_insn(file, reloc->sym->sec);
if (!insn) {
WARN("can't find reachable insn at %s+0x%x",
@@ -531,6 +683,52 @@ static int create_static_call_sections(struct objtool_file *file)
return 0;
}
+static int create_retpoline_sites_sections(struct objtool_file *file)
+{
+ struct instruction *insn;
+ struct section *sec;
+ int idx;
+
+ sec = find_section_by_name(file->elf, ".retpoline_sites");
+ if (sec) {
+ WARN("file already has .retpoline_sites, skipping");
+ return 0;
+ }
+
+ idx = 0;
+ list_for_each_entry(insn, &file->retpoline_call_list, call_node)
+ idx++;
+
+ if (!idx)
+ return 0;
+
+ sec = elf_create_section(file->elf, ".retpoline_sites", 0,
+ sizeof(int), idx);
+ if (!sec) {
+ WARN("elf_create_section: .retpoline_sites");
+ return -1;
+ }
+
+ idx = 0;
+ list_for_each_entry(insn, &file->retpoline_call_list, call_node) {
+
+ int *site = (int *)sec->data->d_buf + idx;
+ *site = 0;
+
+ if (elf_add_reloc_to_insn(file->elf, sec,
+ idx * sizeof(int),
+ R_X86_64_PC32,
+ insn->sec, insn->offset)) {
+ WARN("elf_add_reloc_to_insn: .retpoline_sites");
+ return -1;
+ }
+
+ idx++;
+ }
+
+ return 0;
+}
+
static int create_mcount_loc_sections(struct objtool_file *file)
{
struct section *sec;
@@ -549,7 +747,7 @@ static int create_mcount_loc_sections(struct objtool_file *file)
return 0;
idx = 0;
- list_for_each_entry(insn, &file->mcount_loc_list, mcount_loc_node)
+ list_for_each_entry(insn, &file->mcount_loc_list, call_node)
idx++;
sec = elf_create_section(file->elf, "__mcount_loc", 0, sizeof(unsigned long), idx);
@@ -557,7 +755,7 @@ static int create_mcount_loc_sections(struct objtool_file *file)
return -1;
idx = 0;
- list_for_each_entry(insn, &file->mcount_loc_list, mcount_loc_node) {
+ list_for_each_entry(insn, &file->mcount_loc_list, call_node) {
loc = (unsigned long *)sec->data->d_buf + idx;
memset(loc, 0, sizeof(unsigned long));
@@ -817,6 +1015,9 @@ static struct reloc *insn_reloc(struct objtool_file *file, struct instruction *i
return NULL;
if (!insn->reloc) {
+ if (!file)
+ return NULL;
+
insn->reloc = find_reloc_by_dest_range(file->elf, insn->sec,
insn->offset, insn->len);
if (!insn->reloc) {
@@ -828,6 +1029,136 @@ static struct reloc *insn_reloc(struct objtool_file *file, struct instruction *i
return insn->reloc;
}
+static void remove_insn_ops(struct instruction *insn)
+{
+ struct stack_op *op, *tmp;
+
+ list_for_each_entry_safe(op, tmp, &insn->stack_ops, list) {
+ list_del(&op->list);
+ free(op);
+ }
+}
+
+static void annotate_call_site(struct objtool_file *file,
+ struct instruction *insn, bool sibling)
+{
+ struct reloc *reloc = insn_reloc(file, insn);
+ struct symbol *sym = insn->call_dest;
+
+ if (!sym)
+ sym = reloc->sym;
+
+ /*
+ * Alternative replacement code is just template code which is
+ * sometimes copied to the original instruction. For now, don't
+ * annotate it. (In the future we might consider annotating the
+ * original instruction if/when it ever makes sense to do so.)
+ */
+ if (!strcmp(insn->sec->name, ".altinstr_replacement"))
+ return;
+
+ if (sym->static_call_tramp) {
+ list_add_tail(&insn->call_node, &file->static_call_list);
+ return;
+ }
+
+ if (sym->retpoline_thunk) {
+ list_add_tail(&insn->call_node, &file->retpoline_call_list);
+ return;
+ }
+
+ /*
+ * Many compilers cannot disable KCOV with a function attribute
+ * so they need a little help, NOP out any KCOV calls from noinstr
+ * text.
+ */
+ if (insn->sec->noinstr && sym->kcov) {
+ if (reloc) {
+ reloc->type = R_NONE;
+ elf_write_reloc(file->elf, reloc);
+ }
+
+ elf_write_insn(file->elf, insn->sec,
+ insn->offset, insn->len,
+ sibling ? arch_ret_insn(insn->len)
+ : arch_nop_insn(insn->len));
+
+ insn->type = sibling ? INSN_RETURN : INSN_NOP;
+ return;
+ }
+
+ if (mcount && sym->fentry) {
+ if (sibling)
+ WARN_FUNC("Tail call to __fentry__ !?!?", insn->sec, insn->offset);
+
+ if (reloc) {
+ reloc->type = R_NONE;
+ elf_write_reloc(file->elf, reloc);
+ }
+
+ elf_write_insn(file->elf, insn->sec,
+ insn->offset, insn->len,
+ arch_nop_insn(insn->len));
+
+ insn->type = INSN_NOP;
+
+ list_add_tail(&insn->call_node, &file->mcount_loc_list);
+ return;
+ }
+}
+
+static void add_call_dest(struct objtool_file *file, struct instruction *insn,
+ struct symbol *dest, bool sibling)
+{
+ insn->call_dest = dest;
+ if (!dest)
+ return;
+
+ /*
+ * Whatever stack impact regular CALLs have, should be undone
+ * by the RETURN of the called function.
+ *
+ * Annotated intra-function calls retain the stack_ops but
+ * are converted to JUMP, see read_intra_function_calls().
+ */
+ remove_insn_ops(insn);
+
+ annotate_call_site(file, insn, sibling);
+}
+
+static void add_retpoline_call(struct objtool_file *file, struct instruction *insn)
+{
+ /*
+ * Retpoline calls/jumps are really dynamic calls/jumps in disguise,
+ * so convert them accordingly.
+ */
+ switch (insn->type) {
+ case INSN_CALL:
+ insn->type = INSN_CALL_DYNAMIC;
+ break;
+ case INSN_JUMP_UNCONDITIONAL:
+ insn->type = INSN_JUMP_DYNAMIC;
+ break;
+ case INSN_JUMP_CONDITIONAL:
+ insn->type = INSN_JUMP_DYNAMIC_CONDITIONAL;
+ break;
+ default:
+ return;
+ }
+
+ insn->retpoline_safe = true;
+
+ /*
+ * Whatever stack impact regular CALLs have, should be undone
+ * by the RETURN of the called function.
+ *
+ * Annotated intra-function calls retain the stack_ops but
+ * are converted to JUMP, see read_intra_function_calls().
+ */
+ remove_insn_ops(insn);
+
+ annotate_call_site(file, insn, false);
+}
/*
* Find the destination instructions for all jumps.
*/
@@ -849,28 +1180,12 @@ static int add_jump_destinations(struct objtool_file *file)
} else if (reloc->sym->type == STT_SECTION) {
dest_sec = reloc->sym->sec;
dest_off = arch_dest_reloc_offset(reloc->addend);
- } else if (arch_is_retpoline(reloc->sym)) {
- /*
- * Retpoline jumps are really dynamic jumps in
- * disguise, so convert them accordingly.
- */
- if (insn->type == INSN_JUMP_UNCONDITIONAL)
- insn->type = INSN_JUMP_DYNAMIC;
- else
- insn->type = INSN_JUMP_DYNAMIC_CONDITIONAL;
-
- list_add_tail(&insn->call_node,
- &file->retpoline_call_list);
-
- insn->retpoline_safe = true;
+ } else if (reloc->sym->retpoline_thunk) {
+ add_retpoline_call(file, insn);
continue;
} else if (insn->func) {
/* internal or external sibling call (with reloc) */
- insn->call_dest = reloc->sym;
- if (insn->call_dest->static_call_tramp) {
- list_add_tail(&insn->call_node,
- &file->static_call_list);
- }
+ add_call_dest(file, insn, reloc->sym, true);
continue;
} else if (reloc->sym->sec->idx) {
dest_sec = reloc->sym->sec;
@@ -926,13 +1241,8 @@ static int add_jump_destinations(struct objtool_file *file)
} else if (insn->jump_dest->func->pfunc != insn->func->pfunc &&
insn->jump_dest->offset == insn->jump_dest->func->offset) {
-
/* internal sibling call (without reloc) */
- insn->call_dest = insn->jump_dest->func;
- if (insn->call_dest->static_call_tramp) {
- list_add_tail(&insn->call_node,
- &file->static_call_list);
- }
+ add_call_dest(file, insn, insn->jump_dest->func, true);
}
}
}
@@ -940,16 +1250,6 @@ static int add_jump_destinations(struct objtool_file *file)
return 0;
}
-static void remove_insn_ops(struct instruction *insn)
-{
- struct stack_op *op, *tmp;
-
- list_for_each_entry_safe(op, tmp, &insn->stack_ops, list) {
- list_del(&op->list);
- free(op);
- }
-}
-
static struct symbol *find_call_destination(struct section *sec, unsigned long offset)
{
struct symbol *call_dest;
@@ -968,6 +1268,7 @@ static int add_call_destinations(struct objtool_file *file)
{
struct instruction *insn;
unsigned long dest_off;
+ struct symbol *dest;
struct reloc *reloc;
for_each_insn(file, insn) {
@@ -977,7 +1278,9 @@ static int add_call_destinations(struct objtool_file *file)
reloc = insn_reloc(file, insn);
if (!reloc) {
dest_off = arch_jump_destination(insn);
- insn->call_dest = find_call_destination(insn->sec, dest_off);
+ dest = find_call_destination(insn->sec, dest_off);
+
+ add_call_dest(file, insn, dest, false);
if (insn->ignore)
continue;
@@ -995,9 +1298,8 @@ static int add_call_destinations(struct objtool_file *file)
} else if (reloc->sym->type == STT_SECTION) {
dest_off = arch_dest_reloc_offset(reloc->addend);
- insn->call_dest = find_call_destination(reloc->sym->sec,
- dest_off);
- if (!insn->call_dest) {
+ dest = find_call_destination(reloc->sym->sec, dest_off);
+ if (!dest) {
WARN_FUNC("can't find call dest symbol at %s+0x%lx",
insn->sec, insn->offset,
reloc->sym->sec->name,
@@ -1005,70 +1307,13 @@ static int add_call_destinations(struct objtool_file *file)
return -1;
}
- } else if (arch_is_retpoline(reloc->sym)) {
- /*
- * Retpoline calls are really dynamic calls in
- * disguise, so convert them accordingly.
- */
- insn->type = INSN_CALL_DYNAMIC;
- insn->retpoline_safe = true;
+ add_call_dest(file, insn, dest, false);
- list_add_tail(&insn->call_node,
- &file->retpoline_call_list);
-
- remove_insn_ops(insn);
- continue;
+ } else if (reloc->sym->retpoline_thunk) {
+ add_retpoline_call(file, insn);
} else
- insn->call_dest = reloc->sym;
-
- if (insn->call_dest && insn->call_dest->static_call_tramp) {
- list_add_tail(&insn->call_node,
- &file->static_call_list);
- }
-
- /*
- * Many compilers cannot disable KCOV with a function attribute
- * so they need a little help, NOP out any KCOV calls from noinstr
- * text.
- */
- if (insn->sec->noinstr &&
- !strncmp(insn->call_dest->name, "__sanitizer_cov_", 16)) {
- if (reloc) {
- reloc->type = R_NONE;
- elf_write_reloc(file->elf, reloc);
- }
-
- elf_write_insn(file->elf, insn->sec,
- insn->offset, insn->len,
- arch_nop_insn(insn->len));
- insn->type = INSN_NOP;
- }
-
- if (mcount && !strcmp(insn->call_dest->name, "__fentry__")) {
- if (reloc) {
- reloc->type = R_NONE;
- elf_write_reloc(file->elf, reloc);
- }
-
- elf_write_insn(file->elf, insn->sec,
- insn->offset, insn->len,
- arch_nop_insn(insn->len));
-
- insn->type = INSN_NOP;
-
- list_add_tail(&insn->mcount_loc_node,
- &file->mcount_loc_list);
- }
-
- /*
- * Whatever stack impact regular CALLs have, should be undone
- * by the RETURN of the called function.
- *
- * Annotated intra-function calls retain the stack_ops but
- * are converted to JUMP, see read_intra_function_calls().
- */
- remove_insn_ops(insn);
+ add_call_dest(file, insn, reloc->sym, false);
}
return 0;
@@ -1136,7 +1381,6 @@ static int handle_group_alt(struct objtool_file *file,
memset(nop, 0, sizeof(*nop));
INIT_LIST_HEAD(&nop->alts);
INIT_LIST_HEAD(&nop->stack_ops);
- init_cfi_state(&nop->cfi);
nop->sec = special_alt->new_sec;
nop->offset = special_alt->new_off + special_alt->new_len;
@@ -1545,10 +1789,11 @@ static void set_func_state(struct cfi_state *state)
static int read_unwind_hints(struct objtool_file *file)
{
+ struct cfi_state cfi = init_cfi;
struct section *sec, *relocsec;
- struct reloc *reloc;
struct unwind_hint *hint;
struct instruction *insn;
+ struct reloc *reloc;
int i;
sec = find_section_by_name(file->elf, ".discard.unwind_hints");
@@ -1561,14 +1806,14 @@ static int read_unwind_hints(struct objtool_file *file)
return -1;
}
- if (sec->len % sizeof(struct unwind_hint)) {
+ if (sec->sh.sh_size % sizeof(struct unwind_hint)) {
WARN("struct unwind_hint size mismatch");
return -1;
}
file->hints = true;
- for (i = 0; i < sec->len / sizeof(struct unwind_hint); i++) {
+ for (i = 0; i < sec->sh.sh_size / sizeof(struct unwind_hint); i++) {
hint = (struct unwind_hint *)sec->data->d_buf + i;
reloc = find_reloc_by_dest(file->elf, sec, i * sizeof(*hint));
@@ -1586,19 +1831,24 @@ static int read_unwind_hints(struct objtool_file *file)
insn->hint = true;
if (hint->type == UNWIND_HINT_TYPE_FUNC) {
- set_func_state(&insn->cfi);
+ insn->cfi = &func_cfi;
continue;
}
- if (arch_decode_hint_reg(insn, hint->sp_reg)) {
+ if (insn->cfi)
+ cfi = *(insn->cfi);
+
+ if (arch_decode_hint_reg(hint->sp_reg, &cfi.cfa.base)) {
WARN_FUNC("unsupported unwind_hint sp base reg %d",
insn->sec, insn->offset, hint->sp_reg);
return -1;
}
- insn->cfi.cfa.offset = bswap_if_needed(hint->sp_offset);
- insn->cfi.type = hint->type;
- insn->cfi.end = hint->end;
+ cfi.cfa.offset = bswap_if_needed(hint->sp_offset);
+ cfi.type = hint->type;
+ cfi.end = hint->end;
+
+ insn->cfi = cfi_hash_find_or_add(&cfi);
}
return 0;
@@ -1737,17 +1987,28 @@ static int read_intra_function_calls(struct objtool_file *file)
return 0;
}
-static int read_static_call_tramps(struct objtool_file *file)
+static int classify_symbols(struct objtool_file *file)
{
struct section *sec;
struct symbol *func;
for_each_sec(file, sec) {
list_for_each_entry(func, &sec->symbol_list, list) {
- if (func->bind == STB_GLOBAL &&
- !strncmp(func->name, STATIC_CALL_TRAMP_PREFIX_STR,
+ if (func->bind != STB_GLOBAL)
+ continue;
+
+ if (!strncmp(func->name, STATIC_CALL_TRAMP_PREFIX_STR,
strlen(STATIC_CALL_TRAMP_PREFIX_STR)))
func->static_call_tramp = true;
+
+ if (arch_is_retpoline(func))
+ func->retpoline_thunk = true;
+
+ if (!strcmp(func->name, "__fentry__"))
+ func->fentry = true;
+
+ if (!strncmp(func->name, "__sanitizer_cov_", 16))
+ func->kcov = true;
}
}
@@ -1780,17 +2041,16 @@ static void mark_rodata(struct objtool_file *file)
file->rodata = found;
}
-__weak int arch_rewrite_retpolines(struct objtool_file *file)
-{
- return 0;
-}
-
static int decode_sections(struct objtool_file *file)
{
int ret;
mark_rodata(file);
+ ret = init_pv_ops(file);
+ if (ret)
+ return ret;
+
ret = decode_instructions(file);
if (ret)
return ret;
@@ -1809,7 +2069,7 @@ static int decode_sections(struct objtool_file *file)
/*
* Must be before add_{jump_call}_destination.
*/
- ret = read_static_call_tramps(file);
+ ret = classify_symbols(file);
if (ret)
return ret;
@@ -1853,23 +2113,14 @@ static int decode_sections(struct objtool_file *file)
if (ret)
return ret;
- /*
- * Must be after add_special_section_alts(), since this will emit
- * alternatives. Must be after add_{jump,call}_destination(), since
- * those create the call insn lists.
- */
- ret = arch_rewrite_retpolines(file);
- if (ret)
- return ret;
-
return 0;
}
static bool is_fentry_call(struct instruction *insn)
{
- if (insn->type == INSN_CALL && insn->call_dest &&
- insn->call_dest->type == STT_NOTYPE &&
- !strcmp(insn->call_dest->name, "__fentry__"))
+ if (insn->type == INSN_CALL &&
+ insn->call_dest &&
+ insn->call_dest->fentry)
return true;
return false;
@@ -2452,13 +2703,18 @@ static int propagate_alt_cfi(struct objtool_file *file, struct instruction *insn
if (!insn->alt_group)
return 0;
+ if (!insn->cfi) {
+ WARN("CFI missing");
+ return -1;
+ }
+
alt_cfi = insn->alt_group->cfi;
group_off = insn->offset - insn->alt_group->first_insn->offset;
if (!alt_cfi[group_off]) {
- alt_cfi[group_off] = &insn->cfi;
+ alt_cfi[group_off] = insn->cfi;
} else {
- if (memcmp(alt_cfi[group_off], &insn->cfi, sizeof(struct cfi_state))) {
+ if (cficmp(alt_cfi[group_off], insn->cfi)) {
WARN_FUNC("stack layout conflict in alternatives",
insn->sec, insn->offset);
return -1;
@@ -2509,9 +2765,14 @@ static int handle_insn_ops(struct instruction *insn,
static bool insn_cfi_match(struct instruction *insn, struct cfi_state *cfi2)
{
- struct cfi_state *cfi1 = &insn->cfi;
+ struct cfi_state *cfi1 = insn->cfi;
int i;
+ if (!cfi1) {
+ WARN("CFI missing");
+ return false;
+ }
+
if (memcmp(&cfi1->cfa, &cfi2->cfa, sizeof(cfi1->cfa))) {
WARN_FUNC("stack state mismatch: cfa1=%d%+d cfa2=%d%+d",
@@ -2562,20 +2823,64 @@ static inline bool func_uaccess_safe(struct symbol *func)
static inline const char *call_dest_name(struct instruction *insn)
{
+ static char pvname[16];
+ struct reloc *rel;
+ int idx;
+
if (insn->call_dest)
return insn->call_dest->name;
+ rel = insn_reloc(NULL, insn);
+ if (rel && !strcmp(rel->sym->name, "pv_ops")) {
+ idx = (rel->addend / sizeof(void *));
+ snprintf(pvname, sizeof(pvname), "pv_ops[%d]", idx);
+ return pvname;
+ }
+
return "{dynamic}";
}
-static inline bool noinstr_call_dest(struct symbol *func)
+static bool pv_call_dest(struct objtool_file *file, struct instruction *insn)
+{
+ struct symbol *target;
+ struct reloc *rel;
+ int idx;
+
+ rel = insn_reloc(file, insn);
+ if (!rel || strcmp(rel->sym->name, "pv_ops"))
+ return false;
+
+ idx = (arch_dest_reloc_offset(rel->addend) / sizeof(void *));
+
+ if (file->pv_ops[idx].clean)
+ return true;
+
+ file->pv_ops[idx].clean = true;
+
+ list_for_each_entry(target, &file->pv_ops[idx].targets, pv_target) {
+ if (!target->sec->noinstr) {
+ WARN("pv_ops[%d]: %s", idx, target->name);
+ file->pv_ops[idx].clean = false;
+ }
+ }
+
+ return file->pv_ops[idx].clean;
+}
+
+static inline bool noinstr_call_dest(struct objtool_file *file,
+ struct instruction *insn,
+ struct symbol *func)
{
/*
* We can't deal with indirect function calls at present;
* assume they're instrumented.
*/
- if (!func)
+ if (!func) {
+ if (file->pv_ops)
+ return pv_call_dest(file, insn);
+
return false;
+ }
/*
* If the symbol is from a noinstr section; we good.
@@ -2594,10 +2899,12 @@ static inline bool noinstr_call_dest(struct symbol *func)
return false;
}
-static int validate_call(struct instruction *insn, struct insn_state *state)
+static int validate_call(struct objtool_file *file,
+ struct instruction *insn,
+ struct insn_state *state)
{
if (state->noinstr && state->instr <= 0 &&
- !noinstr_call_dest(insn->call_dest)) {
+ !noinstr_call_dest(file, insn, insn->call_dest)) {
WARN_FUNC("call to %s() leaves .noinstr.text section",
insn->sec, insn->offset, call_dest_name(insn));
return 1;
@@ -2618,7 +2925,9 @@ static int validate_call(struct instruction *insn, struct insn_state *state)
return 0;
}
-static int validate_sibling_call(struct instruction *insn, struct insn_state *state)
+static int validate_sibling_call(struct objtool_file *file,
+ struct instruction *insn,
+ struct insn_state *state)
{
if (has_modified_stack_frame(insn, state)) {
WARN_FUNC("sibling call from callable instruction with modified stack frame",
@@ -2626,7 +2935,7 @@ static int validate_sibling_call(struct instruction *insn, struct insn_state *st
return 1;
}
- return validate_call(insn, state);
+ return validate_call(file, insn, state);
}
static int validate_return(struct symbol *func, struct instruction *insn, struct insn_state *state)
@@ -2696,7 +3005,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
struct instruction *insn, struct insn_state state)
{
struct alternative *alt;
- struct instruction *next_insn;
+ struct instruction *next_insn, *prev_insn = NULL;
struct section *sec;
u8 visited;
int ret;
@@ -2725,15 +3034,25 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
if (insn->visited & visited)
return 0;
+ } else {
+ nr_insns_visited++;
}
if (state.noinstr)
state.instr += insn->instr;
- if (insn->hint)
- state.cfi = insn->cfi;
- else
- insn->cfi = state.cfi;
+ if (insn->hint) {
+ state.cfi = *insn->cfi;
+ } else {
+ /* XXX track if we actually changed state.cfi */
+
+ if (prev_insn && !cficmp(prev_insn->cfi, &state.cfi)) {
+ insn->cfi = prev_insn->cfi;
+ nr_cfi_reused++;
+ } else {
+ insn->cfi = cfi_hash_find_or_add(&state.cfi);
+ }
+ }
insn->visited |= visited;
@@ -2769,7 +3088,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
case INSN_CALL:
case INSN_CALL_DYNAMIC:
- ret = validate_call(insn, &state);
+ ret = validate_call(file, insn, &state);
if (ret)
return ret;
@@ -2788,7 +3107,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
case INSN_JUMP_CONDITIONAL:
case INSN_JUMP_UNCONDITIONAL:
if (is_sibling_call(insn)) {
- ret = validate_sibling_call(insn, &state);
+ ret = validate_sibling_call(file, insn, &state);
if (ret)
return ret;
@@ -2810,7 +3129,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
case INSN_JUMP_DYNAMIC:
case INSN_JUMP_DYNAMIC_CONDITIONAL:
if (is_sibling_call(insn)) {
- ret = validate_sibling_call(insn, &state);
+ ret = validate_sibling_call(file, insn, &state);
if (ret)
return ret;
}
@@ -2883,6 +3202,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
return 1;
}
+ prev_insn = insn;
insn = next_insn;
}
@@ -2909,7 +3229,7 @@ static int validate_unwind_hints(struct objtool_file *file, struct section *sec)
}
while (&insn->list != &file->insn_list && (!sec || insn->sec == sec)) {
- if (insn->hint && !insn->visited) {
+ if (insn->hint && !insn->visited && !insn->ignore) {
ret = validate_branch(file, insn->func, insn, state);
if (ret && backtrace)
BT_FUNC("<=== (hint)", insn);
@@ -3138,10 +3458,20 @@ int check(struct objtool_file *file)
int ret, warnings = 0;
arch_initial_func_cfi_state(&initial_func_cfi);
+ init_cfi_state(&init_cfi);
+ init_cfi_state(&func_cfi);
+ set_func_state(&func_cfi);
+
+ if (!cfi_hash_alloc(1UL << (file->elf->symbol_bits - 3)))
+ goto out;
+
+ cfi_hash_add(&init_cfi);
+ cfi_hash_add(&func_cfi);
ret = decode_sections(file);
if (ret < 0)
goto out;
+
warnings += ret;
if (list_empty(&file->insn_list))
@@ -3185,6 +3515,13 @@ int check(struct objtool_file *file)
goto out;
warnings += ret;
+ if (retpoline) {
+ ret = create_retpoline_sites_sections(file);
+ if (ret < 0)
+ goto out;
+ warnings += ret;
+ }
+
if (mcount) {
ret = create_mcount_loc_sections(file);
if (ret < 0)
@@ -3192,6 +3529,13 @@ int check(struct objtool_file *file)
warnings += ret;
}
+ if (stats) {
+ printf("nr_insns_visited: %ld\n", nr_insns_visited);
+ printf("nr_cfi: %ld\n", nr_cfi);
+ printf("nr_cfi_reused: %ld\n", nr_cfi_reused);
+ printf("nr_cfi_cache: %ld\n", nr_cfi_cache);
+ }
+
out:
/*
* For now, don't fail the kernel build on fatal warnings. These