From: Josh Poimboeuf <jpoimboe@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Sami Tolvanen <samitolvanen@google.com>,
Jann Horn <jannh@google.com>,
the arch/x86 maintainers <x86@kernel.org>,
Masahiro Yamada <masahiroy@kernel.org>,
Steven Rostedt <rostedt@goodmis.org>,
Will Deacon <will@kernel.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
"Paul E. McKenney" <paulmck@kernel.org>,
Kees Cook <keescook@chromium.org>,
Nick Desaulniers <ndesaulniers@google.com>,
clang-built-linux <clang-built-linux@googlegroups.com>,
Kernel Hardening <kernel-hardening@lists.openwall.com>,
linux-arch <linux-arch@vger.kernel.org>,
Linux ARM <linux-arm-kernel@lists.infradead.org>,
linux-kbuild <linux-kbuild@vger.kernel.org>,
kernel list <linux-kernel@vger.kernel.org>,
linux-pci@vger.kernel.org
Subject: Re: [PATCH v6 22/25] x86/asm: annotate indirect jumps
Date: Wed, 21 Oct 2020 16:27:47 -0500 [thread overview]
Message-ID: <20201021212747.ofk74lugt4hhjdzg@treble> (raw)
In-Reply-To: <20201021093213.GV2651@hirez.programming.kicks-ass.net>
On Wed, Oct 21, 2020 at 11:32:13AM +0200, Peter Zijlstra wrote:
> On Wed, Oct 21, 2020 at 10:56:06AM +0200, Peter Zijlstra wrote:
>
> > I do not see these in particular, although I do see a lot of:
> >
> > "sibling call from callable instruction with modified stack frame"
>
> defconfig-build/vmlinux.o: warning: objtool: msr_write()+0x10a: sibling call from callable instruction with modified stack frame
> defconfig-build/vmlinux.o: warning: objtool: msr_write()+0x99: (branch)
> defconfig-build/vmlinux.o: warning: objtool: msr_write()+0x3e: (branch)
> defconfig-build/vmlinux.o: warning: objtool: msr_write()+0x0: <=== (sym)
>
> $ nm defconfig-build/vmlinux.o | grep msr_write
> 0000000000043250 t msr_write
> 00000000004289c0 T msr_write
> 0000000000003056 t msr_write.cold
>
> Below 'fixes' it. So this is also caused by duplicate symbols.
There's a new linker flag for renaming duplicates:
https://sourceware.org/bugzilla/show_bug.cgi?id=26391
But I guess that doesn't help us now.
I don't have access to GCC 10 at the moment so I can't recreate it.
Does this fix it?
diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index 4e1d7460574b..aecdf25b2381 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -217,11 +217,14 @@ struct symbol *find_func_containing(struct section *sec, unsigned long offset)
return NULL;
}
+#define for_each_possible_sym(elf, name, sym) \
+ elf_hash_for_each_possible(elf->symbol_name_hash, sym, name_hash, str_hash(name))
+
struct symbol *find_symbol_by_name(const struct elf *elf, const char *name)
{
struct symbol *sym;
- elf_hash_for_each_possible(elf->symbol_name_hash, sym, name_hash, str_hash(name))
+ for_each_possible_sym(elf, name, sym)
if (!strcmp(sym->name, name))
return sym;
@@ -432,6 +435,8 @@ static int read_symbols(struct elf *elf)
list_for_each_entry(sym, &sec->symbol_list, list) {
char pname[MAX_NAME_LEN + 1];
size_t pnamelen;
+ struct symbol *psym;
+
if (sym->type != STT_FUNC)
continue;
@@ -454,8 +459,14 @@ static int read_symbols(struct elf *elf)
strncpy(pname, sym->name, pnamelen);
pname[pnamelen] = '\0';
- pfunc = find_symbol_by_name(elf, pname);
-
+ pfunc = NULL;
+ for_each_possible_sym(elf, pname, psym) {
+ if ((!psym->cfunc || psym->cfunc == psym) &&
+ !strcmp(psym->name, pname)) {
+ pfunc = psym;
+ break;
+ }
+ }
if (!pfunc) {
WARN("%s(): can't find parent function",
sym->name);
next prev parent reply other threads:[~2020-10-21 21:28 UTC|newest]
Thread overview: 73+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-13 0:31 [PATCH v6 00/25] Add support for Clang LTO Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 01/25] kbuild: preprocess module linker script Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 02/25] objtool: Add a pass for generating __mcount_loc Sami Tolvanen
2020-10-14 16:50 ` Ingo Molnar
2020-10-14 18:21 ` Peter Zijlstra
2020-10-15 20:10 ` Josh Poimboeuf
2020-10-13 0:31 ` [PATCH v6 03/25] objtool: Don't autodetect vmlinux.o Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 04/25] tracing: move function tracer options to Kconfig Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 05/25] tracing: add support for objtool mcount Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 06/25] x86, build: use " Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 07/25] treewide: remove DISABLE_LTO Sami Tolvanen
2020-10-14 22:43 ` Kees Cook
2020-10-17 1:46 ` Masahiro Yamada
2020-10-13 0:31 ` [PATCH v6 08/25] kbuild: add support for Clang LTO Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 09/25] kbuild: lto: fix module versioning Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 10/25] objtool: Split noinstr validation from --vmlinux Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 11/25] kbuild: lto: postpone objtool Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 12/25] kbuild: lto: limit inlining Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 13/25] kbuild: lto: merge module sections Sami Tolvanen
2020-10-14 22:49 ` Kees Cook
2020-10-20 16:42 ` Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 14/25] kbuild: lto: remove duplicate dependencies from .mod files Sami Tolvanen
2020-10-14 22:50 ` Kees Cook
2020-12-03 17:59 ` Masahiro Yamada
2020-12-03 18:47 ` Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 15/25] init: lto: ensure initcall ordering Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 16/25] init: lto: fix PREL32 relocations Sami Tolvanen
2020-10-14 22:53 ` Kees Cook
2020-10-15 0:12 ` Jann Horn
2020-10-13 0:31 ` [PATCH v6 17/25] PCI: Fix PREL32 relocations for LTO Sami Tolvanen
2020-10-14 22:58 ` Kees Cook
2020-10-13 0:31 ` [PATCH v6 18/25] modpost: lto: strip .lto from module names Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 19/25] scripts/mod: disable LTO for empty.c Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 20/25] efi/libstub: disable LTO Sami Tolvanen
2020-10-13 0:31 ` [PATCH v6 21/25] drivers/misc/lkdtm: disable LTO for rodata.o Sami Tolvanen
2020-10-13 0:32 ` [PATCH v6 22/25] x86/asm: annotate indirect jumps Sami Tolvanen
2020-10-14 22:46 ` Kees Cook
2020-10-14 23:23 ` Jann Horn
2020-10-15 10:22 ` Peter Zijlstra
2020-10-15 20:39 ` Josh Poimboeuf
2020-10-20 16:45 ` Sami Tolvanen
2020-10-20 18:52 ` Josh Poimboeuf
2020-10-20 19:24 ` Sami Tolvanen
2020-10-21 8:56 ` Peter Zijlstra
2020-10-21 9:08 ` Peter Zijlstra
2020-10-21 9:32 ` Peter Zijlstra
2020-10-21 21:27 ` Josh Poimboeuf [this message]
2020-10-22 7:25 ` Peter Zijlstra
2020-10-23 17:48 ` Sami Tolvanen
2020-10-23 18:04 ` Nick Desaulniers
2020-10-21 15:01 ` Sami Tolvanen
2020-10-22 0:22 ` Sami Tolvanen
2020-10-23 17:36 ` Sami Tolvanen
2020-11-09 23:11 ` Sami Tolvanen
2020-11-10 2:29 ` Josh Poimboeuf
2020-11-10 3:18 ` Nick Desaulniers
2020-11-10 4:48 ` Sami Tolvanen
2020-11-10 16:11 ` Josh Poimboeuf
2020-11-10 17:46 ` Josh Poimboeuf
2020-11-10 18:59 ` Sami Tolvanen
2020-11-13 19:54 ` Josh Poimboeuf
2020-11-13 20:24 ` Sami Tolvanen
2020-11-13 20:52 ` Josh Poimboeuf
2020-11-13 22:34 ` Josh Poimboeuf
2020-11-13 22:54 ` Sami Tolvanen
2020-11-13 22:56 ` Josh Poimboeuf
2020-11-13 23:31 ` Sami Tolvanen
2020-11-14 0:49 ` Josh Poimboeuf
2020-10-21 9:51 ` Peter Zijlstra
2020-10-21 18:30 ` Josh Poimboeuf
2020-10-13 0:32 ` [PATCH v6 23/25] x86, vdso: disable LTO only for vDSO Sami Tolvanen
2020-10-13 0:32 ` [PATCH v6 24/25] x86, cpu: disable LTO for cpu.c Sami Tolvanen
2020-10-13 0:32 ` [PATCH v6 25/25] x86, build: allow LTO_CLANG and THINLTO to be selected Sami Tolvanen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20201021212747.ofk74lugt4hhjdzg@treble \
--to=jpoimboe@redhat.com \
--cc=clang-built-linux@googlegroups.com \
--cc=gregkh@linuxfoundation.org \
--cc=jannh@google.com \
--cc=keescook@chromium.org \
--cc=kernel-hardening@lists.openwall.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kbuild@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=masahiroy@kernel.org \
--cc=ndesaulniers@google.com \
--cc=paulmck@kernel.org \
--cc=peterz@infradead.org \
--cc=rostedt@goodmis.org \
--cc=samitolvanen@google.com \
--cc=will@kernel.org \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).