Hi Bixuan, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on sparc-next/master] [also build test WARNING on net-next/master net/master linus/master v5.8-rc5 next-20200716] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Bixuan-Cui/net-neterion-vxge-reduce-stack-usage-in-VXGE_COMPLETE_VPATH_TX/20200716-173219 base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next.git master config: s390-allyesconfig (attached as .config) compiler: s390-linux-gcc (GCC) 9.3.0 reproduce (this is a W=1 build): 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 COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=s390 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): 91 | #define this_cpu_add_8(pcp, val) arch_this_cpu_add(pcp, val, "laag", "agsi", long) | ^~~~~~~~~~~~~~~~~ include/linux/percpu-defs.h:380:11: note: in expansion of macro 'this_cpu_add_8' 380 | case 8: stem##8(variable, __VA_ARGS__);break; \ | ^~~~ include/linux/percpu-defs.h:509:33: note: in expansion of macro '__pcpu_size_call' 509 | #define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, pcp, val) | ^~~~~~~~~~~~~~~~ include/linux/percpu-defs.h:519:33: note: in expansion of macro 'this_cpu_add' 519 | #define this_cpu_sub(pcp, val) this_cpu_add(pcp, -(typeof(pcp))(val)) | ^~~~~~~~~~~~ include/linux/percpu-defs.h:521:28: note: in expansion of macro 'this_cpu_sub' 521 | #define this_cpu_dec(pcp) this_cpu_sub(pcp, 1) | ^~~~~~~~~~~~ include/net/sch_generic.h:872:2: note: in expansion of macro 'this_cpu_dec' 872 | this_cpu_dec(sch->cpu_qstats->qlen); | ^~~~~~~~~~~~ include/net/sch_generic.h: In function 'qdisc_qstats_cpu_requeues_inc': arch/s390/include/asm/percpu.h:74:21: warning: comparison is always true due to limited range of data type [-Wtype-limits] 74 | ((szcast)val__ > -129) && ((szcast)val__ < 128)) { \ | ^ arch/s390/include/asm/percpu.h:91:34: note: in expansion of macro 'arch_this_cpu_add' 91 | #define this_cpu_add_8(pcp, val) arch_this_cpu_add(pcp, val, "laag", "agsi", long) | ^~~~~~~~~~~~~~~~~ include/linux/percpu-defs.h:380:11: note: in expansion of macro 'this_cpu_add_8' 380 | case 8: stem##8(variable, __VA_ARGS__);break; \ | ^~~~ include/linux/percpu-defs.h:509:33: note: in expansion of macro '__pcpu_size_call' 509 | #define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, pcp, val) | ^~~~~~~~~~~~~~~~ include/linux/percpu-defs.h:520:28: note: in expansion of macro 'this_cpu_add' 520 | #define this_cpu_inc(pcp) this_cpu_add(pcp, 1) | ^~~~~~~~~~~~ include/net/sch_generic.h:877:2: note: in expansion of macro 'this_cpu_inc' 877 | this_cpu_inc(sch->cpu_qstats->requeues); | ^~~~~~~~~~~~ include/net/sch_generic.h: In function 'qdisc_qstats_cpu_drop': arch/s390/include/asm/percpu.h:74:21: warning: comparison is always true due to limited range of data type [-Wtype-limits] 74 | ((szcast)val__ > -129) && ((szcast)val__ < 128)) { \ | ^ arch/s390/include/asm/percpu.h:91:34: note: in expansion of macro 'arch_this_cpu_add' 91 | #define this_cpu_add_8(pcp, val) arch_this_cpu_add(pcp, val, "laag", "agsi", long) | ^~~~~~~~~~~~~~~~~ include/linux/percpu-defs.h:380:11: note: in expansion of macro 'this_cpu_add_8' 380 | case 8: stem##8(variable, __VA_ARGS__);break; \ | ^~~~ include/linux/percpu-defs.h:509:33: note: in expansion of macro '__pcpu_size_call' 509 | #define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, pcp, val) | ^~~~~~~~~~~~~~~~ include/linux/percpu-defs.h:520:28: note: in expansion of macro 'this_cpu_add' 520 | #define this_cpu_inc(pcp) this_cpu_add(pcp, 1) | ^~~~~~~~~~~~ include/net/sch_generic.h:902:2: note: in expansion of macro 'this_cpu_inc' 902 | this_cpu_inc(sch->cpu_qstats->drops); | ^~~~~~~~~~~~ include/net/sch_generic.h: In function 'qdisc_update_stats_at_enqueue': arch/s390/include/asm/percpu.h:74:21: warning: comparison is always true due to limited range of data type [-Wtype-limits] 74 | ((szcast)val__ > -129) && ((szcast)val__ < 128)) { \ | ^ arch/s390/include/asm/percpu.h:91:34: note: in expansion of macro 'arch_this_cpu_add' 91 | #define this_cpu_add_8(pcp, val) arch_this_cpu_add(pcp, val, "laag", "agsi", long) | ^~~~~~~~~~~~~~~~~ include/linux/percpu-defs.h:380:11: note: in expansion of macro 'this_cpu_add_8' 380 | case 8: stem##8(variable, __VA_ARGS__);break; \ | ^~~~ include/linux/percpu-defs.h:509:33: note: in expansion of macro '__pcpu_size_call' 509 | #define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, pcp, val) | ^~~~~~~~~~~~~~~~ include/net/sch_generic.h:1101:3: note: in expansion of macro 'this_cpu_add' 1101 | this_cpu_add(sch->cpu_qstats->backlog, pkt_len); | ^~~~~~~~~~~~ include/net/sch_generic.h: In function 'mini_qdisc_qstats_cpu_drop': arch/s390/include/asm/percpu.h:74:21: warning: comparison is always true due to limited range of data type [-Wtype-limits] 74 | ((szcast)val__ > -129) && ((szcast)val__ < 128)) { \ | ^ arch/s390/include/asm/percpu.h:91:34: note: in expansion of macro 'arch_this_cpu_add' 91 | #define this_cpu_add_8(pcp, val) arch_this_cpu_add(pcp, val, "laag", "agsi", long) | ^~~~~~~~~~~~~~~~~ include/linux/percpu-defs.h:380:11: note: in expansion of macro 'this_cpu_add_8' 380 | case 8: stem##8(variable, __VA_ARGS__);break; \ | ^~~~ include/linux/percpu-defs.h:509:33: note: in expansion of macro '__pcpu_size_call' 509 | #define this_cpu_add(pcp, val) __pcpu_size_call(this_cpu_add_, pcp, val) | ^~~~~~~~~~~~~~~~ include/linux/percpu-defs.h:520:28: note: in expansion of macro 'this_cpu_add' 520 | #define this_cpu_inc(pcp) this_cpu_add(pcp, 1) | ^~~~~~~~~~~~ include/net/sch_generic.h:1270:2: note: in expansion of macro 'this_cpu_inc' 1270 | this_cpu_inc(miniq->cpu_qstats->drops); | ^~~~~~~~~~~~ drivers/net/ethernet/neterion/vxge/vxge-main.c: In function 'VXGE_COMPLETE_VPATH_TX': drivers/net/ethernet/neterion/vxge/vxge-main.c:103:19: error: conflicting types for 'completed' 103 | struct sk_buff **completed; | ^~~~~~~~~ drivers/net/ethernet/neterion/vxge/vxge-main.c:102:18: note: previous declaration of 'completed' was here 102 | struct sk_buff *completed[NR_SKB_COMPLETED]; | ^~~~~~~~~ drivers/net/ethernet/neterion/vxge/vxge-main.c:126:2: error: implicit declaration of function 'free' [-Werror=implicit-function-declaration] 126 | free(completed); | ^~~~ >> drivers/net/ethernet/neterion/vxge/vxge-main.c:126:2: warning: incompatible implicit declaration of built-in function 'free' drivers/net/ethernet/neterion/vxge/vxge-main.c:60:1: note: include '' or provide a declaration of 'free' 59 | #include "vxge-main.h" +++ |+#include 60 | #include "vxge-reg.h" cc1: some warnings being treated as errors vim +/free +126 drivers/net/ethernet/neterion/vxge/vxge-main.c 96 97 static inline void VXGE_COMPLETE_VPATH_TX(struct vxge_fifo *fifo) 98 { 99 struct sk_buff **skb_ptr = NULL; 100 struct sk_buff **temp; 101 #define NR_SKB_COMPLETED 128 102 struct sk_buff *completed[NR_SKB_COMPLETED]; 103 struct sk_buff **completed; 104 int more; 105 106 completed = kcalloc(NR_SKB_COMPLETED, sizeof(*completed), 107 GFP_KERNEL); 108 if (!completed) 109 return; 110 111 do { 112 more = 0; 113 skb_ptr = completed; 114 115 if (__netif_tx_trylock(fifo->txq)) { 116 vxge_hw_vpath_poll_tx(fifo->handle, &skb_ptr, 117 NR_SKB_COMPLETED, &more); 118 __netif_tx_unlock(fifo->txq); 119 } 120 121 /* free SKBs */ 122 for (temp = completed; temp != skb_ptr; temp++) 123 dev_consume_skb_irq(*temp); 124 } while (more); 125 > 126 free(completed); 127 } 128 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org