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-rw-r--r--tools/objtool/arch.h2
-rw-r--r--tools/objtool/arch/x86/decode.c20
-rw-r--r--tools/objtool/cfi.h2
-rw-r--r--tools/objtool/check.c154
-rw-r--r--tools/objtool/check.h2
-rw-r--r--tools/objtool/orc_gen.c15
6 files changed, 160 insertions, 35 deletions
diff --git a/tools/objtool/arch.h b/tools/objtool/arch.h
index 8918de4f8189..35e3f94413eb 100644
--- a/tools/objtool/arch.h
+++ b/tools/objtool/arch.h
@@ -84,7 +84,7 @@ unsigned long arch_dest_reloc_offset(int addend);
const char *arch_nop_insn(int len);
-int arch_decode_hint_reg(struct instruction *insn, u8 sp_reg);
+int arch_decode_hint_reg(u8 sp_reg, int *base);
bool arch_is_retpoline(struct symbol *sym);
diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index 99b47720dce9..5005a4811157 100644
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -706,34 +706,32 @@ int arch_rewrite_retpolines(struct objtool_file *file)
return 0;
}
-int arch_decode_hint_reg(struct instruction *insn, u8 sp_reg)
+int arch_decode_hint_reg(u8 sp_reg, int *base)
{
- struct cfi_reg *cfa = &insn->cfi.cfa;
-
switch (sp_reg) {
case ORC_REG_UNDEFINED:
- cfa->base = CFI_UNDEFINED;
+ *base = CFI_UNDEFINED;
break;
case ORC_REG_SP:
- cfa->base = CFI_SP;
+ *base = CFI_SP;
break;
case ORC_REG_BP:
- cfa->base = CFI_BP;
+ *base = CFI_BP;
break;
case ORC_REG_SP_INDIRECT:
- cfa->base = CFI_SP_INDIRECT;
+ *base = CFI_SP_INDIRECT;
break;
case ORC_REG_R10:
- cfa->base = CFI_R10;
+ *base = CFI_R10;
break;
case ORC_REG_R13:
- cfa->base = CFI_R13;
+ *base = CFI_R13;
break;
case ORC_REG_DI:
- cfa->base = CFI_DI;
+ *base = CFI_DI;
break;
case ORC_REG_DX:
- cfa->base = CFI_DX;
+ *base = CFI_DX;
break;
default:
return -1;
diff --git a/tools/objtool/cfi.h b/tools/objtool/cfi.h
index c7c59c6a44ee..f579802d7ec2 100644
--- a/tools/objtool/cfi.h
+++ b/tools/objtool/cfi.h
@@ -7,6 +7,7 @@
#define _OBJTOOL_CFI_H
#include "cfi_regs.h"
+#include <linux/list.h>
#define CFI_UNDEFINED -1
#define CFI_CFA -2
@@ -24,6 +25,7 @@ struct cfi_init_state {
};
struct cfi_state {
+ struct hlist_node hash; /* must be first, cficmp() */
struct cfi_reg regs[CFI_NUM_REGS];
struct cfi_reg vals[CFI_NUM_REGS];
struct cfi_reg cfa;
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index eb180c78f440..b6c56c7bb837 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 "builtin.h"
#include "cfi.h"
@@ -25,7 +26,11 @@ 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)
@@ -265,6 +270,78 @@ 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(void)
+{
+ cfi_bits = vmlinux ? ELF_HASH_BITS - 3 : 13;
+ 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 +352,6 @@ 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) {
@@ -301,7 +377,6 @@ 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;
@@ -1077,7 +1152,6 @@ 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;
@@ -1454,10 +1528,11 @@ 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");
@@ -1495,19 +1570,24 @@ 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 = hint->sp_offset;
- insn->cfi.type = hint->type;
- insn->cfi.end = hint->end;
+ cfi.cfa.offset = hint->sp_offset;
+ cfi.type = hint->type;
+ cfi.end = hint->end;
+
+ insn->cfi = cfi_hash_find_or_add(&cfi);
}
return 0;
@@ -2283,13 +2363,18 @@ 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;
@@ -2335,9 +2420,14 @@ static int handle_insn_ops(struct instruction *insn, struct insn_state *state)
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",
@@ -2522,7 +2612,7 @@ 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;
@@ -2551,15 +2641,25 @@ 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;
@@ -2709,6 +2809,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func,
return 1;
}
+ prev_insn = insn;
insn = next_insn;
}
@@ -2964,10 +3065,20 @@ 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())
+ 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))
@@ -3011,6 +3122,13 @@ int check(struct objtool_file *file)
goto out;
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
diff --git a/tools/objtool/check.h b/tools/objtool/check.h
index ca3259eebac8..508f712deba1 100644
--- a/tools/objtool/check.h
+++ b/tools/objtool/check.h
@@ -59,7 +59,7 @@ struct instruction {
struct list_head alts;
struct symbol *func;
struct list_head stack_ops;
- struct cfi_state cfi;
+ struct cfi_state *cfi;
};
static inline bool is_static_jump(struct instruction *insn)
diff --git a/tools/objtool/orc_gen.c b/tools/objtool/orc_gen.c
index 671f3b296c1a..812b33ed9f65 100644
--- a/tools/objtool/orc_gen.c
+++ b/tools/objtool/orc_gen.c
@@ -12,13 +12,19 @@
#include "check.h"
#include "warn.h"
-static int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi)
+static int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi,
+ struct instruction *insn)
{
- struct instruction *insn = container_of(cfi, struct instruction, cfi);
struct cfi_reg *bp = &cfi->regs[CFI_BP];
memset(orc, 0, sizeof(*orc));
+ if (!cfi) {
+ orc->end = 0;
+ orc->sp_reg = ORC_REG_UNDEFINED;
+ return 0;
+ }
+
orc->end = cfi->end;
if (cfi->cfa.base == CFI_UNDEFINED) {
@@ -159,7 +165,7 @@ int orc_create(struct objtool_file *file)
int i;
if (!alt_group) {
- if (init_orc_entry(&orc, &insn->cfi))
+ if (init_orc_entry(&orc, insn->cfi, insn))
return -1;
if (!memcmp(&prev_orc, &orc, sizeof(orc)))
continue;
@@ -183,7 +189,8 @@ int orc_create(struct objtool_file *file)
struct cfi_state *cfi = alt_group->cfi[i];
if (!cfi)
continue;
- if (init_orc_entry(&orc, cfi))
+ /* errors are reported on the original insn */
+ if (init_orc_entry(&orc, cfi, insn))
return -1;
if (!memcmp(&prev_orc, &orc, sizeof(orc)))
continue;