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BUG: KCSAN: data-race in blk_stat_add / enqueue_timer

read to 0xffff888129c2f418 of 8 bytes by interrupt on cpu 1:
 blk_stat_is_active block/blk-stat.h:131 [inline]
 blk_stat_add+0x103/0x2c0 block/blk-stat.c:66
 __blk_mq_end_request+0x22d/0x270 block/blk-mq.c:527
 scsi_end_request+0x1dd/0x360 drivers/scsi/scsi_lib.c:610
 scsi_io_completion+0x11d/0xc80 drivers/scsi/scsi_lib.c:960
 scsi_finish_command+0x283/0x380 drivers/scsi/scsi.c:228
 scsi_softirq_done+0x259/0x280 drivers/scsi/scsi_lib.c:1476
 blk_done_softirq+0x1eb/0x250 block/blk-softirq.c:37
 __do_softirq+0x115/0x33f kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0xbb/0xe0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 do_IRQ+0x81/0x130 arch/x86/kernel/irq.c:263
 ret_from_intr+0x0/0x21
 __tsan_read8+0x0/0x100 kernel/kcsan/core.c:588
 exit_mmap+0x166/0x300 mm/mmap.c:3142
 __mmput kernel/fork.c:1082 [inline]
 mmput+0xea/0x280 kernel/fork.c:1103
 exit_mm kernel/exit.c:485 [inline]
 do_exit+0x4ac/0x18c0 kernel/exit.c:784
 do_group_exit+0xb4/0x1c0 kernel/exit.c:895
 get_signal+0x2a2/0x1320 kernel/signal.c:2734
 do_signal+0x2f/0x6c0 arch/x86/kernel/signal.c:815
 exit_to_usermode_loop+0x250/0x2c0 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:278 [inline]
 do_syscall_64+0x384/0x3a0 arch/x86/entry/common.c:304
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff888129c2f418 of 8 bytes by task 7975 on cpu 0:
 hlist_add_head include/linux/list.h:787 [inline]
 enqueue_timer+0x6c/0x210 kernel/time/timer.c:540
 __mod_timer kernel/time/timer.c:1050 [inline]
 mod_timer+0x4b3/0x7a0 kernel/time/timer.c:1100
 sk_reset_timer+0x2d/0xd0 net/core/sock.c:2840
 inet_csk_reset_xmit_timer include/net/inet_connection_sock.h:234 [inline]
 tcp_reset_xmit_timer include/net/tcp.h:1296 [inline]
 tcp_schedule_loss_probe net/ipv4/tcp_output.c:2520 [inline]
 tcp_schedule_loss_probe+0x2ef/0x390 net/ipv4/tcp_output.c:2476
 tcp_write_xmit+0xe8f/0x3190 net/ipv4/tcp_output.c:2468
 __tcp_push_pending_frames+0x7b/0x1d0 net/ipv4/tcp_output.c:2617
 tcp_push+0x1f7/0x3e0 net/ipv4/tcp.c:726
 tcp_sendmsg_locked+0x1d71/0x2040 net/ipv4/tcp.c:1405
 tcp_sendmsg+0x39/0x60 net/ipv4/tcp.c:1436
 inet_sendmsg+0x6d/0x90 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg+0x9f/0xc0 net/socket.c:659
 sock_write_iter+0x16b/0x210 net/socket.c:991
 call_write_iter include/linux/fs.h:1902 [inline]
 new_sync_write+0x388/0x4a0 fs/read_write.c:483
 __vfs_write+0xb1/0xc0 fs/read_write.c:496
 vfs_write fs/read_write.c:558 [inline]
 vfs_write+0x18a/0x390 fs/read_write.c:542
 ksys_write+0x17b/0x1b0 fs/read_write.c:611
 __do_sys_write fs/read_write.c:623 [inline]
 __se_sys_write fs/read_write.c:620 [inline]
 __x64_sys_write+0x4c/0x60 fs/read_write.c:620
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7975 Comm: syz-fuzzer Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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