From: Peter Zijlstra <peterz@infradead.org>
To: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Kumar Kartikeya Dwivedi <memxor@gmail.com>,
X86 ML <x86@kernel.org>,
joao@overdrivepizza.com, hjl.tools@gmail.com,
Josh Poimboeuf <jpoimboe@redhat.com>,
Andrew Cooper <andrew.cooper3@citrix.com>,
LKML <linux-kernel@vger.kernel.org>,
Nick Desaulniers <ndesaulniers@google.com>,
Kees Cook <keescook@chromium.org>,
Sami Tolvanen <samitolvanen@google.com>,
Mark Rutland <mark.rutland@arm.com>,
alyssa.milburn@intel.com, Miroslav Benes <mbenes@suse.cz>,
Steven Rostedt <rostedt@goodmis.org>,
Masami Hiramatsu <mhiramat@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
Andrii Nakryiko <andrii@kernel.org>, bpf <bpf@vger.kernel.org>,
masahiroy@kernel.org
Subject: Re: [PATCH v4 00/45] x86: Kernel IBT
Date: Mon, 14 Mar 2022 15:59:05 +0100 [thread overview]
Message-ID: <Yi9YOdn5Nbq9BBwd@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20220313085214.GK28057@worktop.programming.kicks-ass.net>
On Sun, Mar 13, 2022 at 09:52:14AM +0100, Peter Zijlstra wrote:
> On Sat, Mar 12, 2022 at 05:33:39PM -0800, Alexei Starovoitov wrote:
> > During the build with gcc 8.5 I see:
> >
> > arch/x86/crypto/crc32c-intel.o: warning: objtool: file already has
> > .ibt_endbr_seal, skipping
> > arch/x86/crypto/crc32c-intel.o: warning: objtool: file already has
> > .orc_unwind section, skipping
> > LD [M] crypto/async_tx/async_xor.ko
> > LD [M] crypto/authenc.ko
> > make[3]: *** [../scripts/Makefile.modfinal:61:
> > arch/x86/crypto/crc32c-intel.ko] Error 255
> > make[3]: *** Waiting for unfinished jobs....
> >
> > but make clean cures it.
> > I suspect it's some missing makefile dependency.
>
> Yes, I recently ran into it; I've been trying to kick Makefile into
> submission but have not had success yet. Will try again on Monday.
>
> Problem appears to be that it will re-link .ko even though .o hasn't
> changed, resulting in duplicate objtool runs. I've been trying to have
> makefile generate .o.objtool empty file to serve as dependency marker to
> avoid doing second objtool run, but like said, no luck yet.
Masahiro-san, I'm trying the below, but afaict it's not working because
the rule for the .o file itself:
$(multi-obj-m): FORCE
$(call if_changed,link_multi-m)
will in fact update the timestamp of the .o file, even if if_changed
nops out the cmd. Concequently all rules that try to use if_changed with
this .o file as a dependency will find it newer and run anyway.
remake -x output of a fs/f2fs/ module (re)build:
Prerequisite 'FORCE' of target 'fs/f2fs/f2fs.o' does not exist.
Must remake target 'fs/f2fs/f2fs.o'.
../scripts/Makefile.build:454: target 'fs/f2fs/f2fs.o' does not exist
##>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
:
##<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
Successfully remade target file 'fs/f2fs/f2fs.o'.
Prerequisite 'fs/f2fs/f2fs.o' is newer than target 'fs/f2fs/f2fs.mod'.
Prerequisite 'FORCE' of target 'fs/f2fs/f2fs.mod' does not exist.
Must remake target 'fs/f2fs/f2fs.mod'.
../scripts/Makefile.build:281: update target 'fs/f2fs/f2fs.mod' due to: fs/f2fs/f2fs.o
##>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
set -e; { echo fs/f2fs/dir.o fs/f2fs/file.o fs/f2fs/inode.o fs/f2fs/namei.o fs/f2fs/hash.o fs/f2fs/super.o fs/f2fs/inline.o fs/f2fs/checkpoint.o fs/f2fs/gc.o fs/f2fs/data.o fs/f2fs/node.o fs/f2fs/segment.o fs/f2fs/recovery.o fs/f2fs/shrinker.o fs/f2fs/extent_cache.o fs/f2fs/sysfs.o fs/f2fs/debug.o fs/f2fs/xattr.o fs/f2fs/acl.o fs/f2fs/iostat.o; echo; } > fs/f2fs/f2fs.mod; printf '%s\n' 'cmd_fs/f2fs/f2fs.mod := { echo fs/f2fs/dir.o fs/f2fs/file.o fs/f2fs/inode.o fs/f2fs/namei.o fs/f2fs/hash.o fs/f2fs/super.o fs/f2fs/inline.o fs/f2fs/checkpoint.o fs/f2fs/gc.o fs/f2fs/data.o fs/f2fs/node.o fs/f2fs/segment.o fs/f2fs/recovery.o fs/f2fs/shrinker.o fs/f2fs/extent_cache.o fs/f2fs/sysfs.o fs/f2fs/debug.o fs/f2fs/xattr.o fs/f2fs/acl.o fs/f2fs/iostat.o; echo; } > fs/f2fs/f2fs.mod' > fs/f2fs/.f2fs.mod.cmd
##<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
Successfully remade target file 'fs/f2fs/f2fs.mod'.
Prerequisite 'fs/f2fs/f2fs.o' is newer than target 'fs/f2fs/f2fs.objtool'.
Prerequisite 'FORCE' of target 'fs/f2fs/f2fs.objtool' does not exist.
Must remake target 'fs/f2fs/f2fs.objtool'.
../scripts/Makefile.build:287: update target 'fs/f2fs/f2fs.objtool' due to: fs/f2fs/f2fs.o
##>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
set -e; { echo fs/f2fs/f2fs.o ; ./tools/objtool/objtool orc generate --module --lto --ibt --no-fp --uaccess fs/f2fs/f2fs.o ; } > fs/f2fs/f2fs.objtool; printf '%s\n' 'cmd_fs/f2fs/f2fs.objtool := { echo fs/f2fs/f2fs.o ; ./tools/objtool/objtool orc generate --module --lto --ibt --no-fp --uaccess fs/f2fs/f2fs.o ; } > fs/f2fs/f2fs.objtool' > fs/f2fs/.f2fs.objtool.cmd
##<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
fs/f2fs/f2fs.o: warning: objtool: file already has .static_call_sites section, skipping
fs/f2fs/f2fs.o: warning: objtool: file already has .ibt_endbr_seal, skipping
fs/f2fs/f2fs.o: warning: objtool: file already has .orc_unwind section, skipping
../scripts/Makefile.build:286: *** [fs/f2fs/f2fs.objtool] error 255
Where we can see that we don't re-generate f2fs.o (empty command), but
then we do re-generate f2fs.mod because f2fs.o is newer and the same
happens for the new f2fs.objtool.
Help?
---
Index: linux-2.6/scripts/Makefile.build
===================================================================
--- linux-2.6.orig/scripts/Makefile.build
+++ linux-2.6/scripts/Makefile.build
@@ -92,6 +92,10 @@ ifdef CONFIG_LTO_CLANG
targets-for-modules += $(patsubst %.o, %.lto.o, $(filter %.o, $(obj-m)))
endif
+ifdef CONFIG_X86_KERNEL_IBT
+targets-for-modules += $(patsubst %.o, %.objtool, $(filter %.o, $(obj-m)))
+endif
+
ifdef need-modorder
targets-for-modules += $(obj)/modules.order
endif
@@ -276,6 +280,12 @@ cmd_mod = { \
$(obj)/%.mod: $(obj)/%$(mod-prelink-ext).o FORCE
$(call if_changed,mod)
+cmd_objtool_mod = \
+ { echo $< $(cmd_objtool) ; } > $@
+
+$(obj)/%.objtool: $(obj)/%$(mod-prelink-ext).o FORCE
+ $(call if_changed,objtool_mod)
+
quiet_cmd_cc_lst_c = MKLST $@
cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
$(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
Index: linux-2.6/scripts/Makefile.lib
===================================================================
--- linux-2.6.orig/scripts/Makefile.lib
+++ linux-2.6/scripts/Makefile.lib
@@ -552,9 +552,8 @@ objtool_args = \
$(if $(CONFIG_FTRACE_MCOUNT_USE_OBJTOOL), --mcount) \
$(if $(CONFIG_SLS), --sls)
-cmd_objtool = $(if $(objtool-enabled), ; $(objtool) $(objtool_args) $@)
-cmd_objtool_mod = $(if $(objtool-enabled), $(objtool) $(objtool_args) $(@:.ko=.o) ; )
-cmd_gen_objtooldep = $(if $(objtool-enabled), { echo ; echo '$@: $$(wildcard $(objtool))' ; } >> $(dot-target).cmd)
+cmd_objtool = $(if $(objtool-enabled), ; $(objtool) $(objtool_args) $(@:.objtool=.o))
+cmd_gen_objtooldep = $(if $(objtool-enabled), { echo ; echo '$(@:.objtool=.o): $$(wildcard $(objtool))' ; } >> $(dot-target).cmd)
endif # CONFIG_STACK_VALIDATION
@@ -575,8 +574,8 @@ $(obj)/%.o: objtool-enabled :=
# instead run objtool on the module as a whole, right before
# the final link pass with the linker script.
-%.ko: objtool-enabled = y
-%.ko: part-of-module := y
+$(obj)/%.objtool: objtool-enabled = y
+$(obj)/%.objtool: part-of-module := y
else
Index: linux-2.6/scripts/Makefile.modfinal
===================================================================
--- linux-2.6.orig/scripts/Makefile.modfinal
+++ linux-2.6/scripts/Makefile.modfinal
@@ -32,7 +32,6 @@ ARCH_POSTLINK := $(wildcard $(srctree)/a
quiet_cmd_ld_ko_o = LD [M] $@
cmd_ld_ko_o += \
- $(cmd_objtool_mod) \
$(LD) -r $(KBUILD_LDFLAGS) \
$(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE) \
-T scripts/module.lds -o $@ $(filter %.o, $^); \
next prev parent reply other threads:[~2022-03-14 14:59 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20220308153011.021123062@infradead.org>
2022-03-08 20:00 ` [PATCH v4 00/45] x86: Kernel IBT Alexei Starovoitov
2022-03-08 22:01 ` Peter Zijlstra
2022-03-08 22:32 ` Peter Zijlstra
2022-03-09 1:02 ` Peter Zijlstra
2022-03-09 19:09 ` Alexei Starovoitov
2022-03-10 9:35 ` Peter Zijlstra
2022-03-10 13:47 ` Peter Zijlstra
2022-03-10 14:37 ` Steven Rostedt
2022-03-11 15:23 ` Peter Zijlstra
2022-03-10 16:29 ` Peter Zijlstra
2022-03-11 10:40 ` Peter Zijlstra
2022-03-11 17:09 ` Alexei Starovoitov
2022-03-12 15:44 ` Peter Zijlstra
2022-03-13 1:33 ` Alexei Starovoitov
2022-03-13 8:52 ` Peter Zijlstra
2022-03-14 14:59 ` Peter Zijlstra [this message]
2022-03-15 8:15 ` Peter Zijlstra
2022-03-15 16:28 ` Masahiro Yamada
2022-03-17 19:44 ` Peter Zijlstra
2022-03-18 2:07 ` David Laight
2022-03-17 18:15 ` Masahiro Yamada
2022-03-17 19:52 ` Peter Zijlstra
2022-03-15 16:26 ` Masahiro Yamada
2022-03-17 19:36 ` Peter Zijlstra
2022-03-14 15:33 ` Peter Zijlstra
2022-03-14 20:44 ` Kumar Kartikeya Dwivedi
2022-03-15 9:00 ` Peter Zijlstra
2022-03-15 10:05 ` Kumar Kartikeya Dwivedi
2022-03-15 10:07 ` Peter Zijlstra
2022-03-15 10:39 ` Peter Zijlstra
2022-03-16 9:35 ` Peter Zijlstra
2022-03-16 11:12 ` Kumar Kartikeya Dwivedi
2022-03-15 18:26 ` Alexei Starovoitov
2022-03-17 20:27 ` Peter Zijlstra
2022-03-10 0:30 ` Nick Desaulniers
2022-03-10 9:05 ` Peter Zijlstra
2022-03-10 9:22 ` David Laight
2022-03-10 10:16 ` Peter Zijlstra
2022-03-10 20:49 ` Nick Desaulniers
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