[PATCH v6 01/29] objtool: Make validate_call() recognize indirect calls to pv_ops[]
From: Valentin Schneider <vschneid@redhat.com>
Date: 2025-10-10 15:41:14
Also in:
linux-arch, linux-arm-kernel, linux-mm, linux-riscv, lkml, loongarch, rcu
Subsystem:
objtool, the rest · Maintainers:
Josh Poimboeuf, Peter Zijlstra, Linus Torvalds
call_dest_name() does not get passed the file pointer of validate_call(),
which means its invocation of insn_reloc() will always return NULL. Make it
take a file pointer.
While at it, make sure call_dest_name() uses arch_dest_reloc_offset(),
otherwise it gets the pv_ops[] offset wrong.
Fabricating an intentional warning shows the change; previously:
vmlinux.o: warning: objtool: __flush_tlb_all_noinstr+0x4: call to {dynamic}() leaves .noinstr.text section
now:
vmlinux.o: warning: objtool: __flush_tlb_all_noinstr+0x4: call to pv_ops[1]() leaves .noinstr.text section
Signed-off-by: Valentin Schneider <vschneid@redhat.com>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
---
tools/objtool/check.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index d14f20ef1db13..5f574ab163cb2 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c@@ -3323,7 +3323,7 @@ static inline bool func_uaccess_safe(struct symbol *func) return false; } -static inline const char *call_dest_name(struct instruction *insn) +static inline const char *call_dest_name(struct objtool_file *file, struct instruction *insn) { static char pvname[19]; struct reloc *reloc;
@@ -3332,9 +3332,9 @@ static inline const char *call_dest_name(struct instruction *insn) if (insn_call_dest(insn)) return insn_call_dest(insn)->name; - reloc = insn_reloc(NULL, insn); + reloc = insn_reloc(file, insn); if (reloc && !strcmp(reloc->sym->name, "pv_ops")) { - idx = (reloc_addend(reloc) / sizeof(void *)); + idx = (arch_dest_reloc_offset(reloc_addend(reloc)) / sizeof(void *)); snprintf(pvname, sizeof(pvname), "pv_ops[%d]", idx); return pvname; }
@@ -3413,17 +3413,19 @@ static int validate_call(struct objtool_file *file, { if (state->noinstr && state->instr <= 0 && !noinstr_call_dest(file, insn, insn_call_dest(insn))) { - WARN_INSN(insn, "call to %s() leaves .noinstr.text section", call_dest_name(insn)); + WARN_INSN(insn, "call to %s() leaves .noinstr.text section", call_dest_name(file, insn)); return 1; } if (state->uaccess && !func_uaccess_safe(insn_call_dest(insn))) { - WARN_INSN(insn, "call to %s() with UACCESS enabled", call_dest_name(insn)); + WARN_INSN(insn, "call to %s() with UACCESS enabled", + call_dest_name(file, insn)); return 1; } if (state->df) { - WARN_INSN(insn, "call to %s() with DF set", call_dest_name(insn)); + WARN_INSN(insn, "call to %s() with DF set", + call_dest_name(file, insn)); return 1; }
--
2.51.0