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BUG: KCSAN: data-race in ktime_get_real_seconds / timekeeping_advance

write to 0xffffffff8603bb08 of 280 bytes by interrupt on cpu 0:
 timekeeping_advance+0x88e/0xd80 include/linux/string.h:378
 update_wall_time+0x19/0x20 kernel/time/timekeeping.c:2137
 tick_do_update_jiffies64+0x1a4/0x250 kernel/time/tick-sched.c:94
 tick_sched_do_timer+0xd4/0xe0 kernel/time/tick-sched.c:138
 tick_sched_timer+0x43/0xe0 kernel/time/tick-sched.c:1292
 __run_hrtimer kernel/time/hrtimer.c:1514 [inline]
 __hrtimer_run_queues+0x274/0x5f0 kernel/time/hrtimer.c:1576
 hrtimer_interrupt+0x22a/0x480 kernel/time/hrtimer.c:1638
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0xdc/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
 arch_local_irq_enable arch/x86/include/asm/paravirt.h:766 [inline]
 bh_lru_install fs/buffer.c:1247 [inline]
 __find_get_block fs/buffer.c:1298 [inline]
 __find_get_block+0x68c/0x760 fs/buffer.c:1290
 sb_find_get_block include/linux/buffer_head.h:338 [inline]
 recently_deleted fs/ext4/ialloc.c:682 [inline]
 find_inode_bit.isra.0+0x161/0x300 fs/ext4/ialloc.c:722
 __ext4_new_inode+0xd10/0x2ec0 fs/ext4/ialloc.c:914
 ext4_mkdir+0x289/0x820 fs/ext4/namei.c:2763
 vfs_mkdir+0x283/0x390 fs/namei.c:3807
 do_mkdirat+0x1ac/0x1f0 fs/namei.c:3830
 __do_sys_mkdir fs/namei.c:3846 [inline]
 __se_sys_mkdir fs/namei.c:3844 [inline]
 __x64_sys_mkdir+0x40/0x50 fs/namei.c:3844
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffffffff8603bb78 of 8 bytes by task 12902 on cpu 1:
 ktime_get_real_seconds+0x20/0x40 kernel/time/timekeeping.c:127
 recently_deleted fs/ext4/ialloc.c:699 [inline]
 find_inode_bit.isra.0+0x1e2/0x300 fs/ext4/ialloc.c:722
 __ext4_new_inode+0xd10/0x2ec0 fs/ext4/ialloc.c:914
 ext4_mkdir+0x289/0x820 fs/ext4/namei.c:2763
 vfs_mkdir+0x283/0x390 fs/namei.c:3807
 do_mkdirat+0x1ac/0x1f0 fs/namei.c:3830
 __do_sys_mkdir fs/namei.c:3846 [inline]
 __se_sys_mkdir fs/namei.c:3844 [inline]
 __x64_sys_mkdir+0x40/0x50 fs/namei.c:3844
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 12902 Comm: syz-executor.2 Not tainted 5.4.0-rc7+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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