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BUG: KCSAN: data-race in ktime_get_real_seconds / timekeeping_advance

write to 0xffffffff86041b08 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_restore arch/x86/include/asm/paravirt.h:756 [inline]
 console_unlock+0x8fa/0xb80 kernel/printk/printk.c:2481
 vprintk_emit+0x38f/0x4e0 kernel/printk/printk.c:1996
 vprintk_default+0x31/0x50 kernel/printk/printk.c:2023
 vprintk_func+0x85/0x140 kernel/printk/printk_safe.c:386
 printk+0x69/0x91 kernel/printk/printk.c:2056
 fscache_print_cookie+0xd6/0x110 fs/fscache/cookie.c:40
 fscache_hash_cookie+0x724/0x850 fs/fscache/cookie.c:223
 __fscache_acquire_cookie fs/fscache/cookie.c:298 [inline]
 __fscache_acquire_cookie+0x17b/0x470 fs/fscache/cookie.c:249
 fscache_acquire_cookie include/linux/fscache.h:334 [inline]
 nfs_fscache_get_client_cookie+0x16c/0x230 fs/nfs/fscache.c:81
 nfs_alloc_client+0x2c2/0x300 fs/nfs/client.c:183
 nfs_get_client+0x39c/0x8d0 fs/nfs/client.c:427
 nfs_init_server+0x1c0/0x790 fs/nfs/client.c:675
 nfs_create_server+0xcc/0x3d0 fs/nfs/client.c:962
 nfs_try_mount+0xa0/0x560 fs/nfs/super.c:1904
 nfs_fs_mount+0x7cb/0x1580 fs/nfs/super.c:2766
 legacy_get_tree+0x7e/0xf0 fs/fs_context.c:647
 vfs_get_tree+0x56/0x1a0 fs/super.c:1545
 do_new_mount fs/namespace.c:2823 [inline]
 do_mount+0x1049/0x1560 fs/namespace.c:3143
 ksys_mount+0xe8/0x160 fs/namespace.c:3352
 __do_sys_mount fs/namespace.c:3366 [inline]
 __se_sys_mount fs/namespace.c:3363 [inline]
 __x64_sys_mount+0x70/0x90 fs/namespace.c:3363
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffffffff86041b78 of 8 bytes by task 14925 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_symlink+0x30e/0x970 fs/ext4/namei.c:3262
 vfs_symlink fs/namei.c:4119 [inline]
 vfs_symlink+0x218/0x310 fs/namei.c:4105
 do_symlinkat+0x1a5/0x1e0 fs/namei.c:4146
 __do_sys_symlink fs/namei.c:4165 [inline]
 __se_sys_symlink fs/namei.c:4163 [inline]
 __x64_sys_symlink+0x3f/0x50 fs/namei.c:4163
 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: 14925 Comm: syz-executor.0 Not tainted 5.4.0-rc6+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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