linux.git/tools/objtool/trace.c, branch v7.2-rc1

objtool: Add insn_sym() helper

2026-05-05T04:16:06+00:00

Alternative replacement instructions awkwardly have insn->sym set to the
function they get patched to rather than the symbol (or rather lack
thereof) they belong to in the file.

This makes it difficult to know where a given instruction actually
lives.

Add a new insn_sym() helper which preserves the existing semantic of
insn->sym.  Rename insn->sym to insn->_sym, which contains the actual
ELF binary symbol (or NULL, for alternative replacements) an instruction
lives in.

The private insn->_sym value will be needed for a subsequent patch.

Acked-by: Song Liu 
Signed-off-by: Josh Poimboeuf

objtool: Improve tracing of alternative instructions

2025-11-21T14:30:11+00:00

When tracing function validation, improve the reporting of
alternative instruction by more clearly showing the different
alternatives beginning and end.

Signed-off-by: Alexandre Chartre 
Signed-off-by: Peter Zijlstra (Intel) 
Acked-by: Josh Poimboeuf 
Link: https://patch.msgid.link/20251121095340.464045-16-alexandre.chartre@oracle.com

objtool: Improve register reporting during function validation

2025-11-21T14:30:10+00:00

When tracing function validation, instruction state changes can
report changes involving registers. These registers are reported
with the name "r" (e.g. "r3"). Print the CPU specific register
name instead of a generic name (e.g. print "rbx" instead of "r3"
on x86).

Signed-off-by: Alexandre Chartre 
Signed-off-by: Peter Zijlstra (Intel) 
Acked-by: Josh Poimboeuf 
Link: https://patch.msgid.link/20251121095340.464045-13-alexandre.chartre@oracle.com

objtool: Trace instruction state changes during function validation

2025-11-21T14:30:10+00:00

During function validation, objtool maintains a per-instruction state,
in particular to track call frame information. When tracing validation,
print any instruction state changes.

Signed-off-by: Alexandre Chartre 
Signed-off-by: Peter Zijlstra (Intel) 
Acked-by: Josh Poimboeuf 
Link: https://patch.msgid.link/20251121095340.464045-12-alexandre.chartre@oracle.com

objtool: Add option to trace function validation

2025-11-21T14:30:09+00:00

Add an option to trace and have information during the validation
of specified functions. Functions are specified with the --trace
option which can be a single function name (e.g. --trace foo to
trace the function with the name "foo"), or a shell wildcard
pattern (e.g. --trace foo* to trace all functions with a name
starting with "foo").

Signed-off-by: Alexandre Chartre 
Signed-off-by: Peter Zijlstra (Intel) 
Acked-by: Josh Poimboeuf 
Link: https://patch.msgid.link/20251121095340.464045-11-alexandre.chartre@oracle.com