This warning isn't a real issue since adapter->num_queues can't be zero. Anyway, I'll use the adapter's syncp in V2 to avoid this warning.
On 11/20/2016 12:09 PM, kbuild test robot wrote: > Hi Netanel, > > [auto build test WARNING on net/master] > > url: > https://github.com/0day-ci/linux/commits/Netanel-Belgazal/Update-ENA-driver-to-version-1-1-2/20161120-165649 > config: i386-randconfig-x009-201647 (attached as .config) > compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901 > reproduce: > # save the attached .config to linux build tree > make ARCH=i386 > > Note: it may well be a FALSE warning. FWIW you are at least aware of it now. > http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings > > All warnings (new ones prefixed by >>): > > Cyclomatic Complexity 2 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_napi_enable_all > Cyclomatic Complexity 1 include/linux/dma-mapping.h:dma_map_single_attrs > Cyclomatic Complexity 1 include/linux/dynamic_queue_limits.h:dql_queued > Cyclomatic Complexity 3 include/linux/netdevice.h:netdev_tx_sent_queue > Cyclomatic Complexity 1 include/linux/netdevice.h:dev_kfree_skb_any > Cyclomatic Complexity 1 include/linux/netdevice.h:netdev_tx_reset_queue > Cyclomatic Complexity 6 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_free_tx_bufs > Cyclomatic Complexity 2 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_free_all_tx_bufs > Cyclomatic Complexity 3 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_free_rx_page > Cyclomatic Complexity 3 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_free_rx_bufs > Cyclomatic Complexity 2 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_free_all_rx_bufs > Cyclomatic Complexity 2 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_down > Cyclomatic Complexity 4 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_close > Cyclomatic Complexity 3 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_update_on_link_change > Cyclomatic Complexity 2 include/linux/netdevice.h:napi_schedule_irqoff > Cyclomatic Complexity 1 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_intr_msix_io > Cyclomatic Complexity 4 include/linux/cpumask.h:cpumask_check > Cyclomatic Complexity 1 include/linux/cpumask.h:cpumask_set_cpu > Cyclomatic Complexity 2 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_setup_io_intr > Cyclomatic Complexity 1 include/linux/interrupt.h:request_irq > Cyclomatic Complexity 9 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_request_io_irq > Cyclomatic Complexity 5 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_request_mgmnt_irq > Cyclomatic Complexity 8 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_setup_tx_resources > Cyclomatic Complexity 5 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_setup_all_tx_resources > Cyclomatic Complexity 5 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_setup_rx_resources > Cyclomatic Complexity 5 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_setup_all_rx_resources > Cyclomatic Complexity 5 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_create_io_tx_queue > Cyclomatic Complexity 4 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_create_all_io_tx_queues > Cyclomatic Complexity 5 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_create_io_rx_queue > Cyclomatic Complexity 4 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_create_all_io_rx_queues > Cyclomatic Complexity 2 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_init_napi > Cyclomatic Complexity 4 > drivers/net/ethernet/amazon/ena/ena_eth_com.h:ena_com_update_dev_comp_head > Cyclomatic Complexity 2 > drivers/net/ethernet/amazon/ena/ena_eth_com.h:ena_com_write_sq_doorbell > Cyclomatic Complexity 4 include/linux/netdevice.h:netdev_tx_completed_queue > Cyclomatic Complexity 14 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_clean_tx_irq > Cyclomatic Complexity 2 include/linux/netdevice.h:netif_tx_unlock > Cyclomatic Complexity 1 include/linux/skbuff.h:__netdev_alloc_skb_ip_align > Cyclomatic Complexity 1 include/linux/skbuff.h:netdev_alloc_skb_ip_align > Cyclomatic Complexity 16 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_rx_skb > Cyclomatic Complexity 1 include/linux/gfp.h:__alloc_pages > Cyclomatic Complexity 1 include/linux/gfp.h:__alloc_pages_node > Cyclomatic Complexity 2 include/linux/gfp.h:alloc_pages_node > Cyclomatic Complexity 6 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_alloc_rx_page > Cyclomatic Complexity 8 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_refill_rx_bufs > Cyclomatic Complexity 11 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_clean_rx_irq > Cyclomatic Complexity 4 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_refill_all_rx_bufs > Cyclomatic Complexity 5 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_update_ring_numa_node > Cyclomatic Complexity 8 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_change_mtu > Cyclomatic Complexity 2 include/linux/netdevice.h:napi_schedule > Cyclomatic Complexity 1 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_device_io_resume > Cyclomatic Complexity 1 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_device_io_suspend > Cyclomatic Complexity 2 > include/linux/seqlock.h:seqcount_lockdep_reader_access > Cyclomatic Complexity 1 include/linux/seqlock.h:read_seqcount_begin > Cyclomatic Complexity 1 > include/linux/u64_stats_sync.h:__u64_stats_fetch_begin > Cyclomatic Complexity 1 > include/linux/u64_stats_sync.h:u64_stats_fetch_begin_irq > Cyclomatic Complexity 6 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_get_stats64 > Cyclomatic Complexity 6 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_notification > Cyclomatic Complexity 2 include/linux/skbuff.h:__skb_linearize > Cyclomatic Complexity 2 include/linux/skbuff.h:skb_linearize > Cyclomatic Complexity 5 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_check_and_linearize_skb > Cyclomatic Complexity 3 include/linux/skbuff.h:sw_tx_timestamp > Cyclomatic Complexity 1 include/linux/skbuff.h:skb_tx_timestamp > Cyclomatic Complexity 22 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_start_xmit > Cyclomatic Complexity 1 arch/x86/include/asm/io.h:ioremap > Cyclomatic Complexity 4 include/linux/dma-mapping.h:dma_set_mask > Cyclomatic Complexity 1 include/linux/pci-dma-compat.h:pci_set_dma_mask > Cyclomatic Complexity 2 include/linux/dma-mapping.h:dma_set_coherent_mask > Cyclomatic Complexity 1 > include/linux/pci-dma-compat.h:pci_set_consistent_dma_mask > Cyclomatic Complexity 4 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_config_host_info > Cyclomatic Complexity 12 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_device_init > Cyclomatic Complexity 4 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_calc_io_queue_num > Cyclomatic Complexity 69 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_calc_queue_size > Cyclomatic Complexity 1 include/linux/etherdevice.h:eth_random_addr > Cyclomatic Complexity 1 include/linux/etherdevice.h:eth_hw_addr_random > Cyclomatic Complexity 2 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_set_conf_feat_params > Cyclomatic Complexity 2 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_init_io_rings > Cyclomatic Complexity 1 include/linux/cpu_rmap.h:alloc_irq_cpu_rmap > Cyclomatic Complexity 4 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_init_rx_cpu_rmap > Cyclomatic Complexity 14 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_enable_msix > Cyclomatic Complexity 2 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_intr_msix_mgmnt > Cyclomatic Complexity 1 include/linux/cpumask.h:cpumask_first > Cyclomatic Complexity 1 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_setup_mgmnt_intr > Cyclomatic Complexity 3 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_enable_msix_and_set_admin_interrupts > Cyclomatic Complexity 6 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_rss_init_default > Cyclomatic Complexity 7 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_rss_configure > Cyclomatic Complexity 3 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_up_complete > Cyclomatic Complexity 9 drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_up > Cyclomatic Complexity 7 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_fw_reset_device > Cyclomatic Complexity 6 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_open > Cyclomatic Complexity 8 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_config_debug_area > Cyclomatic Complexity 21 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_probe > Cyclomatic Complexity 2 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_init > Cyclomatic Complexity 1 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_adjust_intr_moderation > Cyclomatic Complexity 4 > drivers/net/ethernet/amazon/ena/ena_netdev.c:ena_io_poll > In file included from include/linux/linkage.h:4:0, > from include/linux/kernel.h:6, > from include/linux/cpumask.h:9, > from include/linux/cpu_rmap.h:13, > from drivers/net/ethernet/amazon/ena/ena_netdev.c:36: > drivers/net/ethernet/amazon/ena/ena_netdev.c: In function > 'ena_get_stats64': >>> include/linux/compiler.h:231:26: warning: 'rx_ring' may be used >>> uninitialized in this function [-Wmaybe-uninitialized] > case 4: *(__u32 *)res = *(volatile __u32 *)p; break; \ > ^ > drivers/net/ethernet/amazon/ena/ena_netdev.c:2188:19: note: 'rx_ring' was > declared here > struct ena_ring *rx_ring, *tx_ring; > ^~~~~~~ > > vim +/rx_ring +231 include/linux/compiler.h > > fe8c8a12 Cesar Eduardo Barros 2013-11-25 215 #ifndef OPTIMIZER_HIDE_VAR > fe8c8a12 Cesar Eduardo Barros 2013-11-25 216 #define > OPTIMIZER_HIDE_VAR(var) barrier() > fe8c8a12 Cesar Eduardo Barros 2013-11-25 217 #endif > fe8c8a12 Cesar Eduardo Barros 2013-11-25 218 > 6f33d587 Rusty Russell 2012-11-22 219 /* Not-quite-unique ID. */ > 6f33d587 Rusty Russell 2012-11-22 220 #ifndef __UNIQUE_ID > 6f33d587 Rusty Russell 2012-11-22 221 # define __UNIQUE_ID(prefix) > __PASTE(__PASTE(__UNIQUE_ID_, prefix), __LINE__) > 6f33d587 Rusty Russell 2012-11-22 222 #endif > 6f33d587 Rusty Russell 2012-11-22 223 > 230fa253 Christian Borntraeger 2014-11-25 224 #include <uapi/linux/types.h> > 230fa253 Christian Borntraeger 2014-11-25 225 > d976441f Andrey Ryabinin 2015-10-19 226 #define __READ_ONCE_SIZE > \ > d976441f Andrey Ryabinin 2015-10-19 227 ({ > \ > d976441f Andrey Ryabinin 2015-10-19 228 switch (size) { > \ > d976441f Andrey Ryabinin 2015-10-19 229 case 1: *(__u8 *)res = > *(volatile __u8 *)p; break; \ > d976441f Andrey Ryabinin 2015-10-19 230 case 2: *(__u16 *)res = > *(volatile __u16 *)p; break; \ > d976441f Andrey Ryabinin 2015-10-19 @231 case 4: *(__u32 *)res = > *(volatile __u32 *)p; break; \ > d976441f Andrey Ryabinin 2015-10-19 232 case 8: *(__u64 *)res = > *(volatile __u64 *)p; break; \ > d976441f Andrey Ryabinin 2015-10-19 233 default: > \ > d976441f Andrey Ryabinin 2015-10-19 234 barrier(); > \ > d976441f Andrey Ryabinin 2015-10-19 235 > __builtin_memcpy((void *)res, (const void *)p, size); \ > d976441f Andrey Ryabinin 2015-10-19 236 barrier(); > \ > d976441f Andrey Ryabinin 2015-10-19 237 } > \ > d976441f Andrey Ryabinin 2015-10-19 238 }) > d976441f Andrey Ryabinin 2015-10-19 239 > > :::::: The code at line 231 was first introduced by commit > :::::: d976441f44bc5d48635d081d277aa76556ffbf8b compiler, atomics, kasan: > Provide READ_ONCE_NOCHECK() > > :::::: TO: Andrey Ryabinin <aryabi...@virtuozzo.com> > :::::: CC: Ingo Molnar <mi...@kernel.org> > > --- > 0-DAY kernel test infrastructure Open Source Technology Center > https://lists.01.org/pipermail/kbuild-all Intel Corporation
