Commit-ID: e10cd8fe8ddfd28a172d2be57ae0e90c7f752e6a Gitweb: https://git.kernel.org/tip/e10cd8fe8ddfd28a172d2be57ae0e90c7f752e6a Author: Josh Poimboeuf <jpoim...@redhat.com> AuthorDate: Wed, 17 Jul 2019 20:36:48 -0500 Committer: Thomas Gleixner <t...@linutronix.de> CommitDate: Thu, 18 Jul 2019 21:01:07 +0200
objtool: Refactor function alias logic - Add an alias check in validate_functions(). With this change, aliases no longer need uaccess_safe set. - Add an alias check in decode_instructions(). With this change, the "if (!insn->func)" check is no longer needed. - Don't create aliases for zero-length functions, as it can have unexpected results. The next patch will spit out a warning for zero-length functions anyway. Signed-off-by: Josh Poimboeuf <jpoim...@redhat.com> Signed-off-by: Thomas Gleixner <t...@linutronix.de> Tested-by: Nick Desaulniers <ndesaulni...@google.com> Acked-by: Peter Zijlstra (Intel) <pet...@infradead.org> Link: https://lkml.kernel.org/r/26a99c31426540f19c9a58b9e10727c385a147bc.1563413318.git.jpoim...@redhat.com --- tools/objtool/check.c | 16 +++++++++------- tools/objtool/elf.c | 2 +- 2 files changed, 10 insertions(+), 8 deletions(-) diff --git a/tools/objtool/check.c b/tools/objtool/check.c index d8a1ce80fded..3f8664b0e3f9 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -276,7 +276,7 @@ static int decode_instructions(struct objtool_file *file) } list_for_each_entry(func, &sec->symbol_list, list) { - if (func->type != STT_FUNC) + if (func->type != STT_FUNC || func->alias != func) continue; if (!find_insn(file, sec, func->offset)) { @@ -286,8 +286,7 @@ static int decode_instructions(struct objtool_file *file) } func_for_each_insn(file, func, insn) - if (!insn->func) - insn->func = func; + insn->func = func; } } @@ -508,7 +507,7 @@ static void add_uaccess_safe(struct objtool_file *file) if (!func) continue; - func->alias->uaccess_safe = true; + func->uaccess_safe = true; } } @@ -1887,7 +1886,7 @@ static bool insn_state_match(struct instruction *insn, struct insn_state *state) static inline bool func_uaccess_safe(struct symbol *func) { if (func) - return func->alias->uaccess_safe; + return func->uaccess_safe; return false; } @@ -2355,14 +2354,17 @@ static int validate_functions(struct objtool_file *file) for_each_sec(file, sec) { list_for_each_entry(func, &sec->symbol_list, list) { - if (func->type != STT_FUNC || func->pfunc != func) + if (func->type != STT_FUNC) + continue; + + if (func->pfunc != func || func->alias != func) continue; insn = find_insn(file, sec, func->offset); if (!insn || insn->ignore || insn->visited) continue; - state.uaccess = func->alias->uaccess_safe; + state.uaccess = func->uaccess_safe; ret = validate_branch(file, func, insn, state); if (ret && backtrace) diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c index e18698262837..9194732a673d 100644 --- a/tools/objtool/elf.c +++ b/tools/objtool/elf.c @@ -278,7 +278,7 @@ static int read_symbols(struct elf *elf) } if (sym->offset == s->offset) { - if (sym->len == s->len && alias == sym) + if (sym->len && sym->len == s->len && alias == sym) alias = s; if (sym->len >= s->len) {
