Re: [PATCH v3 1/2] modpost: rework and consolidate logging interface

From: Jessica Yu
Date: Mon Mar 09 2020 - 06:39:43 EST


+++ Masahiro Yamada [09/03/20 19:20 +0900]:
On Mon, Mar 9, 2020 at 6:59 PM Jessica Yu <jeyu@xxxxxxxxxx> wrote:

+++ Masahiro Yamada [09/03/20 09:40 +0900]:
>Hi Jessica,
>
>
>
>On Sat, Mar 7, 2020 at 1:02 AM Jessica Yu <jeyu@xxxxxxxxxx> wrote:
>>
>> Rework modpost's logging interface by consolidating merror(), warn(), and
>> fatal() to use a single function, modpost_log(). Introduce different
>> logging levels (WARN, ERROR, FATAL) as well. The purpose of this cleanup is
>> to reduce code duplication when deciding whether or not to warn or error
>> out based on a condition.
>>
>> Signed-off-by: Jessica Yu <jeyu@xxxxxxxxxx>
>> ---
>> v3:
>> - remove level variable from modpost_log and just call fprintf in each
>> case
>> - remove warn_unless and just call modpost_log() directly
>> - fix checkpatch error:
>> ERROR: space required before the open parenthesis '('
>> #102: FILE: scripts/mod/modpost.c:61:
>> + switch(loglevel) {
>>
>> scripts/mod/modpost.c | 68 ++++++++++++++++++++++-----------------------------
>> scripts/mod/modpost.h | 14 ++++++++---
>> 2 files changed, 40 insertions(+), 42 deletions(-)
>>
>> diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
>> index 7edfdb2f4497..a2329235a6db 100644
>> --- a/scripts/mod/modpost.c
>> +++ b/scripts/mod/modpost.c
>> @@ -51,41 +51,34 @@ enum export {
>>
>> #define MODULE_NAME_LEN (64 - sizeof(Elf_Addr))
>>
>> -#define PRINTF __attribute__ ((format (printf, 1, 2)))
>> +#define PRINTF __attribute__ ((format (printf, 2, 3)))
>>
>> -PRINTF void fatal(const char *fmt, ...)
>> +PRINTF void modpost_log(enum loglevel loglevel, const char *fmt, ...)
>> {
>
>
>This series looks good to me.
>
>I can queue it up to kbuild tree
>if there is no objection.
>
>
>I just noticed one nit.
>
>Now that modpost_log() is the only user of PRINTF,
>we can delete PRITNF, and directly add the attribute
>to modpost_log(), like this:
>
>
>void __attribute__((format(printf, 2, 3)))
>modpost_log(enum loglevel loglevel, const char *fmt, ...)
>{
> ...
>}
>
>
>If you agree, I can modify it when I apply it.

Yes, I agree with this change. Thank you!

One more thing, it's not immediately obvious to me why the first patch
would cause those kbuild warnings :-/ I'll see if I have any luck
reproducing them locally..



Hmm, this warning option is not so new.


At least, commit 7c0d35a339db6 (4 years ago)
fixed a similar one.

Ah, sorry, I mean the kbuild 0-day bot errors. I am just realizing
the 0-day bot emails are not CC'd to lkml. Here is the error I got
from the bot:

---

I love your patch! Yet something to improve:

[auto build test ERROR on linus/master]
[also build test ERROR on v5.6-rc4 next-20200306]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url: https://github.com/0day-ci/linux/commits/Jessica-Yu/modpost-rework-and-consolidate-logging-interface/20200307-052346
base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 30fe0d07fd7b27d41d9b31a224052cc4e910947a
config: sh-randconfig-a001-20200306 (attached as .config)
compiler: sh4-linux-gcc (GCC) 7.5.0
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
GCC_VERSION=7.5.0 make.cross ARCH=sh
If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <lkp@xxxxxxxxx>

All errors (new ones prefixed by >>):

ERROR: modpost: "adc_single" [arch/sh/boards/mach-hp6xx/hp6xx_apm.ko] undefined!

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx


I use GCC 7.4

If I apply your previous version,
I see build log like follows:




$ gcc --version
gcc (Ubuntu 7.4.0-1ubuntu1~18.04.1) 7.4.0
Copyright (C) 2017 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

masahiro@pug:~/ref/linux$ make defconfig all
HOSTCC scripts/kconfig/conf.o
HOSTCC scripts/kconfig/confdata.o
HOSTCC scripts/kconfig/expr.o
LEX scripts/kconfig/lexer.lex.c
YACC scripts/kconfig/parser.tab.[ch]
HOSTCC scripts/kconfig/lexer.lex.o
HOSTCC scripts/kconfig/parser.tab.o
HOSTCC scripts/kconfig/preprocess.o
HOSTCC scripts/kconfig/symbol.o
HOSTCC scripts/kconfig/util.o
HOSTLD scripts/kconfig/conf
*** Default configuration is based on 'x86_64_defconfig'
#
# configuration written to .config
#
SYSTBL arch/x86/include/generated/asm/syscalls_32.h
SYSHDR arch/x86/include/generated/asm/unistd_32_ia32.h
SYSHDR arch/x86/include/generated/asm/unistd_64_x32.h
SYSTBL arch/x86/include/generated/asm/syscalls_64.h
SYSHDR arch/x86/include/generated/uapi/asm/unistd_32.h
SYSHDR arch/x86/include/generated/uapi/asm/unistd_64.h
SYSHDR arch/x86/include/generated/uapi/asm/unistd_x32.h
HOSTCC arch/x86/tools/relocs_32.o
HOSTCC arch/x86/tools/relocs_64.o
HOSTCC arch/x86/tools/relocs_common.o
HOSTLD arch/x86/tools/relocs
HOSTCC scripts/selinux/genheaders/genheaders
HOSTCC scripts/selinux/mdp/mdp
HOSTCC scripts/kallsyms
HOSTCC scripts/sorttable
HOSTCC scripts/asn1_compiler
HOSTCC scripts/extract-cert
WRAP arch/x86/include/generated/uapi/asm/bpf_perf_event.h
WRAP arch/x86/include/generated/uapi/asm/errno.h
WRAP arch/x86/include/generated/uapi/asm/fcntl.h
WRAP arch/x86/include/generated/uapi/asm/ioctl.h
WRAP arch/x86/include/generated/uapi/asm/ioctls.h
WRAP arch/x86/include/generated/uapi/asm/ipcbuf.h
WRAP arch/x86/include/generated/uapi/asm/param.h
WRAP arch/x86/include/generated/uapi/asm/poll.h
WRAP arch/x86/include/generated/uapi/asm/resource.h
WRAP arch/x86/include/generated/uapi/asm/socket.h
WRAP arch/x86/include/generated/uapi/asm/sockios.h
WRAP arch/x86/include/generated/uapi/asm/termbits.h
WRAP arch/x86/include/generated/uapi/asm/termios.h
WRAP arch/x86/include/generated/uapi/asm/types.h
WRAP arch/x86/include/generated/asm/early_ioremap.h
WRAP arch/x86/include/generated/asm/export.h
WRAP arch/x86/include/generated/asm/mcs_spinlock.h
WRAP arch/x86/include/generated/asm/mm-arch-hooks.h
WRAP arch/x86/include/generated/asm/mmiowb.h
WRAP arch/x86/include/generated/asm/dma-contiguous.h
UPD include/config/kernel.release
UPD include/generated/uapi/linux/version.h
UPD include/generated/utsrelease.h
CC scripts/mod/empty.o
HOSTCC scripts/mod/mk_elfconfig
MKELF scripts/mod/elfconfig.h
HOSTCC scripts/mod/modpost.o
scripts/mod/modpost.c: In function âmodpost_logâ:
scripts/mod/modpost.c:75:2: warning: format not a string literal and
no format arguments [-Wformat-security]
fprintf(stderr, level);
^~~~~~~
CC scripts/mod/devicetable-offsets.s
UPD scripts/mod/devicetable-offsets.h
HOSTCC scripts/mod/file2alias.o
HOSTCC scripts/mod/sumversion.o
HOSTLD scripts/mod/modpost
CC kernel/bounds.s
UPD include/generated/bounds.h
UPD include/generated/timeconst.h
CC arch/x86/kernel/asm-offsets.s


--
Best Regards
Masahiro Yamada