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BUG: KCSAN: data-race in hrtimer_interrupt / print_cpu

write to 0xffff88813bd1dea0 of 8 bytes by interrupt on cpu 1:
 hrtimer_interrupt+0x1e2/0xa10 kernel/time/hrtimer.c:1637
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x6f/0x200 arch/x86/kernel/apic/apic.c:1102
 asm_call_irq_on_stack+0xf/0x20
 __run_sysvec_on_irqstack arch/x86/include/asm/irq_stack.h:37 [inline]
 run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:89 [inline]
 sysvec_apic_timer_interrupt+0x52/0x90 arch/x86/kernel/apic/apic.c:1096
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:628
 radix_tree_iter_tag_clear+0x1/0x150 lib/radix-tree.c:1059
 idr_alloc_u32 lib/idr.c:53 [inline]
 idr_alloc_cyclic+0x1cf/0x2c0 lib/idr.c:125
 __kernfs_new_node+0xbb/0x350 fs/kernfs/dir.c:632
 kernfs_new_node+0x5b/0xd0 fs/kernfs/dir.c:688
 __kernfs_create_file+0x45/0x180 fs/kernfs/file.c:1002
 sysfs_add_file_mode_ns+0x1c1/0x250 fs/sysfs/file.c:306
 create_files fs/sysfs/group.c:64 [inline]
 internal_create_group+0x2e4/0x850 fs/sysfs/group.c:149
 internal_create_groups fs/sysfs/group.c:189 [inline]
 sysfs_create_groups+0x3d/0xf0 fs/sysfs/group.c:215
 create_dir lib/kobject.c:100 [inline]
 kobject_add_internal+0x565/0x820 lib/kobject.c:255
 kobject_add_varg lib/kobject.c:390 [inline]
 kobject_init_and_add+0x14e/0x200 lib/kobject.c:473
 rx_queue_add_kobject net/core/net-sysfs.c:969 [inline]
 net_rx_queue_update_kobjects+0xf5/0x2e0 net/core/net-sysfs.c:1020
 register_queue_kobjects net/core/net-sysfs.c:1695 [inline]
 netdev_register_kobject+0x17e/0x230 net/core/net-sysfs.c:1943
 register_netdevice+0xbcf/0x1060 net/core/dev.c:10046
 register_netdev+0x37/0x50 net/core/dev.c:10177
 loopback_net_init+0x52/0xf0 drivers/net/loopback.c:216
 ops_init+0x1e7/0x230 net/core/net_namespace.c:152
 setup_net+0x12b/0x640 net/core/net_namespace.c:342
 copy_net_ns+0x2a9/0x450 net/core/net_namespace.c:483
 create_new_namespaces+0x231/0x560 kernel/nsproxy.c:110
 copy_namespaces+0x116/0x160 kernel/nsproxy.c:178
 copy_process+0x12ad/0x2da0 kernel/fork.c:2102
 kernel_clone+0x14b/0x680 kernel/fork.c:2464
 __do_sys_clone kernel/fork.c:2581 [inline]
 __se_sys_clone kernel/fork.c:2565 [inline]
 __x64_sys_clone+0xc8/0xf0 kernel/fork.c:2565
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88813bd1dea0 of 8 bytes by task 10380 on cpu 0:
 print_cpu+0x32e/0x690 kernel/time/timer_list.c:133
 timer_list_show+0x114/0x180 kernel/time/timer_list.c:283
 seq_read_iter+0x2d8/0x8e0 fs/seq_file.c:227
 proc_reg_read_iter+0xfc/0x170 fs/proc/inode.c:310
 call_read_iter include/linux/fs.h:1895 [inline]
 generic_file_splice_read+0x22a/0x310 fs/splice.c:311
 do_splice_to fs/splice.c:788 [inline]
 splice_direct_to_actor+0x2aa/0x650 fs/splice.c:867
 do_splice_direct+0xf5/0x170 fs/splice.c:976
 do_sendfile+0x5db/0xca0 fs/read_write.c:1257
 __do_sys_sendfile64 fs/read_write.c:1318 [inline]
 __se_sys_sendfile64 fs/read_write.c:1304 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1304
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10380 Comm: syz-executor.0 Not tainted 5.11.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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