Subject: Re: [PATCH net 1/2] net/sched: taprio: fix picos_per_byte miscalculation

From: kbuild test robot <[email-masked]>
Date: Fri, 15 Mar 2019 00:08:52 +0800

Hi Leandro,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on net/master]

url:    https://github.com/0day-ci/linux/commits/Leandro-Dorileo/net-sched-taprio-fix-picos_per_byte-miscalculation/20190314-231519
config: riscv-allyesconfig (attached as .config)
compiler: riscv64-linux-gcc (GCC) 8.1.0
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=8.1.0 make.cross ARCH=riscv 

All warnings (new ones prefixed by >>):

   In file included from include/linux/printk.h:7,
                    from include/linux/kernel.h:14,
                    from include/asm-generic/bug.h:18,
                    from arch/riscv/include/asm/bug.h:75,
                    from include/linux/bug.h:5,
                    from include/linux/mmdebug.h:5,
                    from include/linux/gfp.h:5,
                    from include/linux/slab.h:15,
                    from net/sched/sch_taprio.c:10:
   net/sched/sch_taprio.c: In function 'taprio_set_picos_per_byte':
>> include/linux/kern_levels.h:5:18: warning: format '%llu' expects argument of type 'long long unsigned int', but argument 3 has type 'long int' [-Wformat=]
    #define KERN_SOH "\001"  /* ASCII Start Of Header */
                     ^~~~~~
   include/linux/kern_levels.h:14:19: note: in expansion of macro 'KERN_SOH'
    #define KERN_INFO KERN_SOH "6" /* informational */
                      ^~~~~~~~
   include/linux/printk.h:310:9: note: in expansion of macro 'KERN_INFO'
     printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
            ^~~~~~~~~
   net/sched/sch_taprio.c:600:2: note: in expansion of macro 'pr_info'
     pr_info("taprio: set %s's picos_per_byte to: %llu, linkspeed: %d\n",
     ^~~~~~~
   net/sched/sch_taprio.c:600:50: note: format string is defined here
     pr_info("taprio: set %s's picos_per_byte to: %llu, linkspeed: %d\n",
                                                  ~~~^
                                                  %lu
--
   In file included from include/linux/printk.h:7,
                    from include/linux/kernel.h:14,
                    from include/asm-generic/bug.h:18,
                    from arch/riscv/include/asm/bug.h:75,
                    from include/linux/bug.h:5,
                    from include/linux/mmdebug.h:5,
                    from include/linux/gfp.h:5,
                    from include/linux/slab.h:15,
                    from net//sched/sch_taprio.c:10:
   net//sched/sch_taprio.c: In function 'taprio_set_picos_per_byte':
>> include/linux/kern_levels.h:5:18: warning: format '%llu' expects argument of type 'long long unsigned int', but argument 3 has type 'long int' [-Wformat=]
    #define KERN_SOH "\001"  /* ASCII Start Of Header */
                     ^~~~~~
   include/linux/kern_levels.h:14:19: note: in expansion of macro 'KERN_SOH'
    #define KERN_INFO KERN_SOH "6" /* informational */
                      ^~~~~~~~
   include/linux/printk.h:310:9: note: in expansion of macro 'KERN_INFO'
     printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
            ^~~~~~~~~
   net//sched/sch_taprio.c:600:2: note: in expansion of macro 'pr_info'
     pr_info("taprio: set %s's picos_per_byte to: %llu, linkspeed: %d\n",
     ^~~~~~~
   net//sched/sch_taprio.c:600:50: note: format string is defined here
     pr_info("taprio: set %s's picos_per_byte to: %llu, linkspeed: %d\n",
                                                  ~~~^
                                                  %lu

vim +5 include/linux/kern_levels.h

314ba352 Joe Perches 2012-07-30  4  
04d2c8c8 Joe Perches 2012-07-30 @5  #define KERN_SOH	"\001"		/* ASCII Start Of Header */
04d2c8c8 Joe Perches 2012-07-30  6  #define KERN_SOH_ASCII	'\001'
04d2c8c8 Joe Perches 2012-07-30  7  

:::::: The code at line 5 was first introduced by commit
:::::: 04d2c8c83d0e3ac5f78aeede51babb3236200112 printk: convert the format for KERN_<LEVEL> to a 2 byte pattern

:::::: TO: Joe Perches <[email-masked]>
:::::: CC: Linus Torvalds <[email-masked]>

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation