================================================================== BUG: KCSAN: data-race in pollwake / pollwake write to 0xffffc9000159f9e0 of 4 bytes by task 3323 on cpu 1: __pollwake fs/select.c:195 [inline] pollwake+0xb6/0x100 fs/select.c:215 __wake_up_common kernel/sched/wait.c:89 [inline] __wake_up_common_lock kernel/sched/wait.c:106 [inline] __wake_up_sync_key+0x52/0x80 kernel/sched/wait.c:173 anon_pipe_write+0x8ba/0xaa0 fs/pipe.c:594 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x4a0/0x8e0 fs/read_write.c:686 ksys_write+0xda/0x1a0 fs/read_write.c:738 __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __x64_sys_write+0x40/0x50 fs/read_write.c:746 x64_sys_call+0x2cdd/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f write to 0xffffc9000159f9e0 of 4 bytes by interrupt on cpu 0: __pollwake fs/select.c:195 [inline] pollwake+0xb6/0x100 fs/select.c:215 __wake_up_common kernel/sched/wait.c:89 [inline] __wake_up_common_lock kernel/sched/wait.c:106 [inline] __wake_up_sync_key+0x52/0x80 kernel/sched/wait.c:173 sock_def_readable+0x70/0x190 net/core/sock.c:3583 tcp_data_ready+0x1ae/0x290 net/ipv4/tcp_input.c:5246 tcp_data_queue+0x15b0/0x3270 net/ipv4/tcp_input.c:5336 tcp_rcv_established+0xa0f/0xef0 net/ipv4/tcp_input.c:6308 tcp_v4_do_rcv+0x672/0x740 net/ipv4/tcp_ipv4.c:1925 tcp_v4_rcv+0x1bd7/0x1f60 net/ipv4/tcp_ipv4.c:2363 ip_protocol_deliver_rcu+0x397/0x780 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x184/0x220 net/ipv4/ip_input.c:233 NF_HOOK include/linux/netfilter.h:317 [inline] ip_local_deliver+0xe8/0x1c0 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:469 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:578 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:627 [inline] ip_sublist_rcv+0x56b/0x650 net/ipv4/ip_input.c:635 ip_list_rcv+0x261/0x290 net/ipv4/ip_input.c:669 __netif_receive_skb_list_ptype net/core/dev.c:6020 [inline] __netif_receive_skb_list_core+0x4dc/0x500 net/core/dev.c:6067 __netif_receive_skb_list net/core/dev.c:6119 [inline] netif_receive_skb_list_internal+0x487/0x600 net/core/dev.c:6210 gro_normal_list include/net/gro.h:532 [inline] napi_complete_done+0x1a3/0x410 net/core/dev.c:6580 virtqueue_napi_complete drivers/net/virtio_net.c:737 [inline] virtnet_poll+0x189f/0x1d10 drivers/net/virtio_net.c:3053 __napi_poll+0x63/0x3a0 net/core/dev.c:7414 napi_poll net/core/dev.c:7478 [inline] net_rx_action+0x391/0x830 net/core/dev.c:7605 handle_softirqs+0xb7/0x290 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0x3a/0xc0 kernel/softirq.c:680 common_interrupt+0x83/0x90 arch/x86/kernel/irq.c:285 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:95 [inline] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x3c/0x60 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] unlock_page_lruvec_irqrestore include/linux/memcontrol.h:1506 [inline] folio_batch_move_lru+0x1e5/0x230 mm/swap.c:174 __folio_batch_add_and_move mm/swap.c:196 [inline] folio_add_lru+0x14a/0x1f0 mm/swap.c:505 shmem_alloc_and_add_folio mm/shmem.c:1949 [inline] shmem_get_folio_gfp+0x7ab/0xd60 mm/shmem.c:2532 shmem_get_folio mm/shmem.c:2638 [inline] shmem_write_begin+0xa8/0x190 mm/shmem.c:3288 generic_perform_write+0x181/0x490 mm/filemap.c:4112 shmem_file_write_iter+0xc5/0xf0 mm/shmem.c:3463 __kernel_write_iter+0x256/0x4c0 fs/read_write.c:619 dump_emit_page fs/coredump.c:1112 [inline] dump_user_range+0x407/0x8c0 fs/coredump.c:1186 elf_core_dump+0x1dc2/0x1f80 fs/binfmt_elf.c:2075 do_coredump+0x1dfd/0x27b0 fs/coredump.c:950 get_signal+0xd85/0xf70 kernel/signal.c:3019 arch_do_signal_or_restart+0x96/0x480 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] irqentry_exit_to_user_mode+0x5e/0xa0 kernel/entry/common.c:184 irqentry_exit+0x12/0x50 kernel/entry/common.c:287 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 value changed: 0x00000000 -> 0x00000001 Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 23308 Comm: syz.3.9657 Tainted: G W 6.15.0-syzkaller-11173-g546b1c9e93c2 #0 PREEMPT(voluntary) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 ==================================================================