summaryrefslogtreecommitdiffstats
path: root/tools/objtool
diff options
context:
space:
mode:
Diffstat (limited to 'tools/objtool')
-rw-r--r--tools/objtool/Documentation/objtool.txt19
-rw-r--r--tools/objtool/arch/x86/decode.c8
-rw-r--r--tools/objtool/arch/x86/special.c23
-rw-r--r--tools/objtool/builtin-check.c4
-rw-r--r--tools/objtool/noreturns.h4
-rw-r--r--tools/objtool/special.c16
6 files changed, 63 insertions, 11 deletions
diff --git a/tools/objtool/Documentation/objtool.txt b/tools/objtool/Documentation/objtool.txt
index fe39c2a8ef0d..7c3ee959b63c 100644
--- a/tools/objtool/Documentation/objtool.txt
+++ b/tools/objtool/Documentation/objtool.txt
@@ -284,6 +284,25 @@ the objtool maintainers.
Otherwise the stack frame may not get created before the call.
+ objtool can help with pinpointing the exact function where it happens:
+
+ $ OBJTOOL_ARGS="--verbose" make arch/x86/kvm/
+
+ arch/x86/kvm/kvm.o: warning: objtool: .altinstr_replacement+0xc5: call without frame pointer save/setup
+ arch/x86/kvm/kvm.o: warning: objtool: em_loop.part.0+0x29: (alt)
+ arch/x86/kvm/kvm.o: warning: objtool: em_loop.part.0+0x0: <=== (sym)
+ LD [M] arch/x86/kvm/kvm-intel.o
+ 0000 0000000000028220 <em_loop.part.0>:
+ 0000 28220: 0f b6 47 61 movzbl 0x61(%rdi),%eax
+ 0004 28224: 3c e2 cmp $0xe2,%al
+ 0006 28226: 74 2c je 28254 <em_loop.part.0+0x34>
+ 0008 28228: 48 8b 57 10 mov 0x10(%rdi),%rdx
+ 000c 2822c: 83 f0 05 xor $0x5,%eax
+ 000f 2822f: 48 c1 e0 04 shl $0x4,%rax
+ 0013 28233: 25 f0 00 00 00 and $0xf0,%eax
+ 0018 28238: 81 e2 d5 08 00 00 and $0x8d5,%edx
+ 001e 2823e: 80 ce 02 or $0x2,%dh
+ ...
2. file.o: warning: objtool: .text+0x53: unreachable instruction
diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c
index 3a1d80a7878d..ed6bff0e01dc 100644
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -125,8 +125,14 @@ bool arch_pc_relative_reloc(struct reloc *reloc)
#define is_RIP() ((modrm_rm & 7) == CFI_BP && modrm_mod == 0)
#define have_SIB() ((modrm_rm & 7) == CFI_SP && mod_is_mem())
+/*
+ * Check the ModRM register. If there is a SIB byte then check with
+ * the SIB base register. But if the SIB base is 5 (i.e. CFI_BP) and
+ * ModRM mod is 0 then there is no base register.
+ */
#define rm_is(reg) (have_SIB() ? \
- sib_base == (reg) && sib_index == CFI_SP : \
+ sib_base == (reg) && sib_index == CFI_SP && \
+ (sib_base != CFI_BP || modrm_mod != 0) : \
modrm_rm == (reg))
#define rm_is_mem(reg) (mod_is_mem() && !is_RIP() && rm_is(reg))
diff --git a/tools/objtool/arch/x86/special.c b/tools/objtool/arch/x86/special.c
index 4134d27c696b..4ea0f9815fda 100644
--- a/tools/objtool/arch/x86/special.c
+++ b/tools/objtool/arch/x86/special.c
@@ -9,6 +9,29 @@
void arch_handle_alternative(unsigned short feature, struct special_alt *alt)
{
+ static struct special_alt *group, *prev;
+
+ /*
+ * Recompute orig_len for nested ALTERNATIVE()s.
+ */
+ if (group && group->orig_sec == alt->orig_sec &&
+ group->orig_off == alt->orig_off) {
+
+ struct special_alt *iter = group;
+ for (;;) {
+ unsigned int len = max(iter->orig_len, alt->orig_len);
+ iter->orig_len = alt->orig_len = len;
+
+ if (iter == prev)
+ break;
+
+ iter = list_next_entry(iter, list);
+ }
+
+ } else group = alt;
+
+ prev = alt;
+
switch (feature) {
case X86_FEATURE_SMAP:
/*
diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c
index 5e21cfb7661d..387d56a7f5fb 100644
--- a/tools/objtool/builtin-check.c
+++ b/tools/objtool/builtin-check.c
@@ -144,7 +144,7 @@ static bool opts_valid(void)
opts.static_call ||
opts.uaccess) {
if (opts.dump_orc) {
- ERROR("--dump can't be combined with other options");
+ ERROR("--dump can't be combined with other actions");
return false;
}
@@ -159,7 +159,7 @@ static bool opts_valid(void)
if (opts.dump_orc)
return true;
- ERROR("At least one command required");
+ ERROR("At least one action required");
return false;
}
diff --git a/tools/objtool/noreturns.h b/tools/objtool/noreturns.h
index 7ebf29c91184..1e8141ef1b15 100644
--- a/tools/objtool/noreturns.h
+++ b/tools/objtool/noreturns.h
@@ -7,12 +7,16 @@
* Yes, this is unfortunate. A better solution is in the works.
*/
NORETURN(__fortify_panic)
+NORETURN(__ia32_sys_exit)
+NORETURN(__ia32_sys_exit_group)
NORETURN(__kunit_abort)
NORETURN(__module_put_and_kthread_exit)
NORETURN(__reiserfs_panic)
NORETURN(__stack_chk_fail)
NORETURN(__tdx_hypercall_failed)
NORETURN(__ubsan_handle_builtin_unreachable)
+NORETURN(__x64_sys_exit)
+NORETURN(__x64_sys_exit_group)
NORETURN(arch_cpu_idle_dead)
NORETURN(bch2_trans_in_restart_error)
NORETURN(bch2_trans_restart_error)
diff --git a/tools/objtool/special.c b/tools/objtool/special.c
index 91b1950f5bd8..097a69db82a0 100644
--- a/tools/objtool/special.c
+++ b/tools/objtool/special.c
@@ -84,6 +84,14 @@ static int get_alt_entry(struct elf *elf, const struct special_entry *entry,
entry->new_len);
}
+ orig_reloc = find_reloc_by_dest(elf, sec, offset + entry->orig);
+ if (!orig_reloc) {
+ WARN_FUNC("can't find orig reloc", sec, offset + entry->orig);
+ return -1;
+ }
+
+ reloc_to_sec_off(orig_reloc, &alt->orig_sec, &alt->orig_off);
+
if (entry->feature) {
unsigned short feature;
@@ -94,14 +102,6 @@ static int get_alt_entry(struct elf *elf, const struct special_entry *entry,
arch_handle_alternative(feature, alt);
}
- orig_reloc = find_reloc_by_dest(elf, sec, offset + entry->orig);
- if (!orig_reloc) {
- WARN_FUNC("can't find orig reloc", sec, offset + entry->orig);
- return -1;
- }
-
- reloc_to_sec_off(orig_reloc, &alt->orig_sec, &alt->orig_off);
-
if (!entry->group || alt->new_len) {
new_reloc = find_reloc_by_dest(elf, sec, offset + entry->new);
if (!new_reloc) {