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BUG: KCSAN: data-race in ktime_get_real_seconds / timekeeping_advance

write to 0xffffffff88ae90c8 of 280 bytes by interrupt on cpu 1:
 timekeeping_advance+0x88e/0xd80 include/linux/string.h:381
 update_wall_time+0x15/0x20 kernel/time/timekeeping.c:2136
 tick_do_update_jiffies64+0x1e5/0x2a0 kernel/time/tick-sched.c:101
 tick_sched_do_timer+0xc7/0xd0 kernel/time/tick-sched.c:147
 tick_sched_timer+0x3f/0xd0 kernel/time/tick-sched.c:1313
 __run_hrtimer kernel/time/hrtimer.c:1520 [inline]
 __hrtimer_run_queues+0x271/0x600 kernel/time/hrtimer.c:1584
 hrtimer_interrupt+0x226/0x490 kernel/time/hrtimer.c:1646
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1113 [inline]
 smp_apic_timer_interrupt+0xd8/0x270 arch/x86/kernel/apic/apic.c:1138
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 get_current arch/x86/include/asm/current.h:15 [inline]
 get_ctx kernel/kcsan/core.c:193 [inline]
 check_access kernel/kcsan/core.c:579 [inline]
 __tsan_unaligned_write4+0xaa/0x110 kernel/kcsan/core.c:769
 rcu_preempt_depth_set kernel/rcu/tree_plugin.h:365 [inline]
 __rcu_read_unlock kernel/rcu/tree_plugin.h:402 [inline]
 __rcu_read_unlock+0xe8/0x390 kernel/rcu/tree_plugin.h:389
 rcu_read_unlock include/linux/rcupdate.h:654 [inline]
 __unlock_page_memcg+0x3e/0xb0 mm/memcontrol.c:2043
 unlock_page_memcg+0x20/0x30 mm/memcontrol.c:2052
 page_remove_file_rmap mm/rmap.c:1269 [inline]
 page_remove_rmap+0x36f/0x7a0 mm/rmap.c:1326
 zap_pte_range mm/memory.c:1092 [inline]
 zap_pmd_range mm/memory.c:1196 [inline]
 zap_pud_range mm/memory.c:1225 [inline]
 zap_p4d_range mm/memory.c:1246 [inline]
 unmap_page_range+0xb23/0x1c50 mm/memory.c:1267
 unmap_single_vma+0x13c/0x1f0 mm/memory.c:1312
 unmap_vmas+0xe2/0x1b0 mm/memory.c:1344
 exit_mmap+0x13e/0x2f0 mm/mmap.c:3150
 __mmput kernel/fork.c:1085 [inline]
 mmput+0xe2/0x260 kernel/fork.c:1106
 exit_mm kernel/exit.c:479 [inline]
 do_exit+0x644/0x11e0 kernel/exit.c:782
 do_group_exit+0xae/0x1a0 kernel/exit.c:893
 get_signal+0x2a7/0x1290 kernel/signal.c:2739
 do_signal+0x2b/0x840 arch/x86/kernel/signal.c:784
 exit_to_usermode_loop+0x24a/0x2c0 arch/x86/entry/common.c:161
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
 do_syscall_64+0x38b/0x3b0 arch/x86/entry/common.c:305
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffffffff88ae9138 of 8 bytes by task 9375 on cpu 0:
 ktime_get_real_seconds+0x1d/0x30 kernel/time/timekeeping.c:127
 recently_deleted fs/ext4/ialloc.c:699 [inline]
 find_inode_bit.isra.0+0x1e7/0x330 fs/ext4/ialloc.c:724
 __ext4_new_inode+0xd7b/0x3020 fs/ext4/ialloc.c:927
 ext4_mkdir+0x271/0x850 fs/ext4/namei.c:2790
 vfs_mkdir+0x281/0x3b0 fs/namei.c:3625
 do_mkdirat+0x1b5/0x200 fs/namei.c:3648
 __do_sys_mkdir fs/namei.c:3664 [inline]
 __se_sys_mkdir fs/namei.c:3662 [inline]
 __x64_sys_mkdir+0x3d/0x50 fs/namei.c:3662
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 9375 Comm: syz-executor.4 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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