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BUG: KCSAN: data-race in pollwake / pollwake

write to 0xffffc9000144fa00 of 4 bytes by interrupt 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+0x4f/0x80 kernel/sched/wait.c:173
 sock_def_readable+0x70/0x190 net/core/sock.c:3533
 tcp_data_ready+0x1ab/0x290 net/ipv4/tcp_input.c:5250
 tcp_data_queue+0x156c/0x3080 net/ipv4/tcp_input.c:5340
 tcp_rcv_established+0x90a/0xea0 net/ipv4/tcp_input.c:6312
 tcp_v4_do_rcv+0x672/0x740 net/ipv4/tcp_ipv4.c:1925
 tcp_v4_rcv+0x1bcf/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:314 [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:5930 [inline]
 __netif_receive_skb_list_core+0x4dc/0x500 net/core/dev.c:5977
 __netif_receive_skb_list net/core/dev.c:6029 [inline]
 netif_receive_skb_list_internal+0x487/0x600 net/core/dev.c:6120
 gro_normal_list include/net/gro.h:532 [inline]
 napi_complete_done+0x1a3/0x410 net/core/dev.c:6490
 virtqueue_napi_complete drivers/net/virtio_net.c:737 [inline]
 virtnet_poll+0x18bf/0x1d00 drivers/net/virtio_net.c:3053
 __napi_poll+0x63/0x3a0 net/core/dev.c:7324
 napi_poll net/core/dev.c:7388 [inline]
 net_rx_action+0x38e/0x7b0 net/core/dev.c:7510
 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_irq include/linux/spinlock_api_smp.h:160 [inline]
 _raw_spin_unlock_irq+0x2f/0x50 kernel/locking/spinlock.c:202
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 tag_pages_for_writeback+0x101/0x290 mm/page-writeback.c:2398
 ext4_do_writepages+0x695/0x2270 fs/ext4/inode.c:2675
 ext4_writepages+0x176/0x300 fs/ext4/inode.c:2829
 do_writepages+0x1d2/0x480 mm/page-writeback.c:2656
 __writeback_single_inode+0x80/0x7c0 fs/fs-writeback.c:1680
 writeback_sb_inodes+0x480/0xa20 fs/fs-writeback.c:1976
 wb_writeback+0x252/0x5c0 fs/fs-writeback.c:2156
 wb_do_writeback fs/fs-writeback.c:2303 [inline]
 wb_workfn+0x194/0x910 fs/fs-writeback.c:2343
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0x4cb/0x9d0 kernel/workqueue.c:3319
 worker_thread+0x582/0x770 kernel/workqueue.c:3400
 kthread+0x486/0x510 kernel/kthread.c:464
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

write to 0xffffc9000144fa00 of 4 bytes by task 4746 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+0x4f/0x80 kernel/sched/wait.c:173
 anon_pipe_write+0x8ba/0xaa0 fs/pipe.c:595
 new_sync_write fs/read_write.c:591 [inline]
 vfs_write+0x49d/0x8d0 fs/read_write.c:684
 ksys_write+0xda/0x1a0 fs/read_write.c:736
 __do_sys_write fs/read_write.c:747 [inline]
 __se_sys_write fs/read_write.c:744 [inline]
 __x64_sys_write+0x40/0x50 fs/read_write.c:744
 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+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 4746 Comm: syz-executor Not tainted 6.15.0-rc4-syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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