From patchwork Mon Dec 4 09:37:09 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Zijlstra X-Patchwork-Id: 13478012 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="TsMsM4Rq" Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DB1F1119; Mon, 4 Dec 2023 01:39:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-Id:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=Jgweoy9v1ry+vJ+0xQvkdC/DCJR/HfQjV7GgwvonHBA=; b=TsMsM4RqmJ30Dxhaj7X6J4Zvnb S1vBqgDpLm/YetggJX/GKdtsZdMYIARCMQTuL89qct50tzNboez/lYKD5uO3NX2mOvnewAo+12F+P tZpcUqtnC7SQLklE7qJe72Y8wk4/wE6R/PWxK4aqk2QFRyxHDiqe4E773IZn/gqrE8ORLRFNzEPj6 LkyyKx7xzYzviXyYUkY6Xqo7NKc5tMTdkXO77Kgg2wlwR7I1pCrTfGT4ipektuCH7g26epOtf7N3y nNMKzkx8qfvtDKIsTMjFgAz4cUYY0bLyefv++/U3k+9SjN3c/ua7Nrll5njDV0bXDXarSA0nB3JGR R0S+ckng==; Received: from j130084.upc-j.chello.nl ([24.132.130.84] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1rA5QZ-000X0Z-5i; Mon, 04 Dec 2023 09:39:47 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 0) id A486B300AA5; Mon, 4 Dec 2023 10:39:45 +0100 (CET) Message-Id: <20231204093732.097671022@infradead.org> User-Agent: quilt/0.65 Date: Mon, 04 Dec 2023 10:37:09 +0100 From: Peter Zijlstra To: Sean Christopherson , Paolo Bonzini , Josh Poimboeuf , Thomas Gleixner Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, x86@kernel.org, kvm@vger.kernel.org Subject: [PATCH 07/11] objtool: Convert ANNOTATE_INTRA_FUNCTION_CALLS to ANNOTATE References: <20231204093702.989848513@infradead.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Signed-off-by: Peter Zijlstra (Intel) --- include/linux/objtool.h | 16 ++---- include/linux/objtool_types.h | 1 tools/include/linux/objtool_types.h | 1 tools/objtool/check.c | 96 ++++++++++++++---------------------- 4 files changed, 47 insertions(+), 67 deletions(-) --- a/include/linux/objtool.h +++ b/include/linux/objtool.h @@ -66,16 +66,6 @@ #else /* __ASSEMBLY__ */ /* - * This macro indicates that the following intra-function call is valid. - * Any non-annotated intra-function call will cause objtool to issue a warning. - */ -#define ANNOTATE_INTRA_FUNCTION_CALL \ - 999: \ - .pushsection .discard.intra_function_calls; \ - .long 999b; \ - .popsection; - -/* * In asm, there are two kinds of code: normal C-type callable functions and * the rest. The normal callable functions can be called by other code, and * don't do anything unusual with the stack. Such normal callable functions @@ -152,6 +142,12 @@ #define ANNOTATE_NOENDBR ANNOTATE type=ANNOTYPE_NOENDBR +/* + * This macro indicates that the following intra-function call is valid. + * Any non-annotated intra-function call will cause objtool to issue a warning. + */ +#define ANNOTATE_INTRA_FUNCTION_CALL ANNOTATE type=ANNOTYPE_INTRA_FUNCTION_CALLS + #endif /* __ASSEMBLY__ */ #else /* !CONFIG_OBJTOOL */ --- a/include/linux/objtool_types.h +++ b/include/linux/objtool_types.h @@ -63,5 +63,6 @@ struct unwind_hint { #define ANNOTYPE_INSTR_END 4 #define ANNOTYPE_UNRET_BEGIN 5 #define ANNOTYPE_IGNORE_ALTS 6 +#define ANNOTYPE_INTRA_FUNCTION_CALLS 7 #endif /* _LINUX_OBJTOOL_TYPES_H */ --- a/tools/include/linux/objtool_types.h +++ b/tools/include/linux/objtool_types.h @@ -63,5 +63,6 @@ struct unwind_hint { #define ANNOTYPE_INSTR_END 4 #define ANNOTYPE_UNRET_BEGIN 5 #define ANNOTYPE_IGNORE_ALTS 6 +#define ANNOTYPE_INTRA_FUNCTION_CALLS 7 #endif /* _LINUX_OBJTOOL_TYPES_H */ --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -2274,7 +2274,8 @@ static int read_unwind_hints(struct objt return 0; } -static int read_annotate(struct objtool_file *file, int (*func)(int type, struct instruction *insn)) +static int read_annotate(struct objtool_file *file, + int (*func)(struct objtool_file *file, int type, struct instruction *insn)) { struct section *rsec, *sec; struct instruction *insn; @@ -2299,7 +2300,7 @@ static int read_annotate(struct objtool_ type = *(u32 *)(sec->data->d_buf + (reloc_idx(reloc) * sec->sh.sh_entsize) + 4); - ret = func(type, insn); + ret = func(file, type, insn); if (ret < 0) return ret; } @@ -2307,7 +2308,7 @@ static int read_annotate(struct objtool_ return 0; } -static int __annotate_ignore_alts(int type, struct instruction *insn) +static int __annotate_ignore_alts(struct objtool_file *file, int type, struct instruction *insn) { if (type != ANNOTYPE_IGNORE_ALTS) return 0; @@ -2316,7 +2317,7 @@ static int __annotate_ignore_alts(int ty return 0; } -static int __annotate_noendbr(int type, struct instruction *insn) +static int __annotate_noendbr(struct objtool_file *file, int type, struct instruction *insn) { if (type != ANNOTYPE_NOENDBR) return 0; @@ -2325,7 +2326,37 @@ static int __annotate_noendbr(int type, return 0; } -static int __annotate_retpoline_safe(int type, struct instruction *insn) +static int __annotate_ifc(struct objtool_file *file, int type, struct instruction *insn) +{ + unsigned long dest_off; + + if (type != ANNOTYPE_INTRA_FUNCTION_CALLS) + return 0; + + if (insn->type != INSN_CALL) { + WARN_INSN(insn, "intra_function_call not a direct call"); + return -1; + } + + /* + * Treat intra-function CALLs as JMPs, but with a stack_op. + * See add_call_destinations(), which strips stack_ops from + * normal CALLs. + */ + insn->type = INSN_JUMP_UNCONDITIONAL; + + dest_off = arch_jump_destination(insn); + insn->jump_dest = find_insn(file, insn->sec, dest_off); + if (!insn->jump_dest) { + WARN_INSN(insn, "can't find call dest at %s+0x%lx", + insn->sec->name, dest_off); + return -1; + } + + return 0; +} + +static int __annotate_retpoline_safe(struct objtool_file *file, int type, struct instruction *insn) { if (type != ANNOTYPE_RETPOLINE_SAFE) return 0; @@ -2342,7 +2373,7 @@ static int __annotate_retpoline_safe(int return 0; } -static int __annotate_instr(int type, struct instruction *insn) +static int __annotate_instr(struct objtool_file *file, int type, struct instruction *insn) { switch (type) { case ANNOTYPE_INSTR_BEGIN: @@ -2360,7 +2391,7 @@ static int __annotate_instr(int type, st return 0; } -static int __annotate_unret(int type, struct instruction *insn) +static int __annotate_unret(struct objtool_file *file, int type, struct instruction *insn) { if (type != ANNOTYPE_UNRET_BEGIN) return 0; @@ -2370,55 +2401,6 @@ static int __annotate_unret(int type, st } -static int read_intra_function_calls(struct objtool_file *file) -{ - struct instruction *insn; - struct section *rsec; - struct reloc *reloc; - - rsec = find_section_by_name(file->elf, ".rela.discard.intra_function_calls"); - if (!rsec) - return 0; - - for_each_reloc(rsec, reloc) { - unsigned long dest_off; - - if (reloc->sym->type != STT_SECTION) { - WARN("unexpected relocation symbol type in %s", - rsec->name); - return -1; - } - - insn = find_insn(file, reloc->sym->sec, reloc_addend(reloc)); - if (!insn) { - WARN("bad .discard.intra_function_call entry"); - return -1; - } - - if (insn->type != INSN_CALL) { - WARN_INSN(insn, "intra_function_call not a direct call"); - return -1; - } - - /* - * Treat intra-function CALLs as JMPs, but with a stack_op. - * See add_call_destinations(), which strips stack_ops from - * normal CALLs. - */ - insn->type = INSN_JUMP_UNCONDITIONAL; - - dest_off = arch_jump_destination(insn); - insn->jump_dest = find_insn(file, insn->sec, dest_off); - if (!insn->jump_dest) { - WARN_INSN(insn, "can't find call dest at %s+0x%lx", - insn->sec->name, dest_off); - return -1; - } - } - - return 0; -} - /* * Return true if name matches an instrumentation function, where calls to that * function from noinstr code can safely be removed, but compilers won't do so. @@ -2554,7 +2536,7 @@ static int decode_sections(struct objtoo * Must be before add_call_destination(); it changes INSN_CALL to * INSN_JUMP. */ - ret = read_intra_function_calls(file); + ret = read_annotate(file, __annotate_ifc); if (ret) return ret;