syzbot

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BUG: KCSAN: data-race in __run_hrtimer kernel/time/hrtimer.c:1416 [inline] and hrtimer_active+0x84/0x1a0
BUG: KCSAN: data-race in __hrtimer_run_queues+0x176/0x600 kernel/time/hrtimer.c:1451 and hrtimer_active+0x84/0x1a0

read to 0xffff88812be1d818 of 8 bytes by task 7 on cpu 1:
 hrtimer_active+0x84/0x1a0 kernel/time/hrtimer.c:1321
 hrtimer_try_to_cancel+0x3c/0x260 kernel/time/hrtimer.c:1135
 hrtimer_cancel+0x29/0x50 kernel/time/hrtimer.c:1161
 napi_disable+0x9c/0xb0 net/core/dev.c:6300
 gro_cells_destroy net/core/gro_cells.c:101 [inline]
 gro_cells_destroy+0xb9/0x1e0 net/core/gro_cells.c:92
 ip6_dev_free+0x22/0x50 net/ipv6/ip6_tunnel.c:249
 netdev_run_todo+0x3eb/0x570 net/core/dev.c:8989
 rtnl_unlock+0x17/0x20 net/core/rtnetlink.c:112
 ip6_tnl_exit_batch_net+0x218/0x240 net/ipv6/ip6_tunnel.c:2268
 ops_exit_list.isra.0+0xa2/0xc0 net/core/net_namespace.c:175
 cleanup_net+0x3f6/0x6a0 net/core/net_namespace.c:594
 process_one_work+0x3d4/0x890 kernel/workqueue.c:2269
 worker_thread+0xa0/0x800 kernel/workqueue.c:2415
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253

write to 0xffff88812be1d818 of 8 bytes by interrupt on cpu 0:
 __run_hrtimer kernel/time/hrtimer.c:1416 [inline]
 __hrtimer_run_queues+0x176/0x600 kernel/time/hrtimer.c:1451
 hrtimer_interrupt+0x22a/0x480 kernel/time/hrtimer.c:1509
 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
 is_enabled kernel/kcsan/core.c:204 [inline]
 __kcsan_check_watchpoint+0x22/0x180 kernel/kcsan/core.c:319
 __lru_cache_add+0x5a/0x1d0 mm/swap.c:401
 lru_cache_add+0x1f/0x30 mm/swap.c:441
 add_to_page_cache_lru+0x188/0x2d0 mm/filemap.c:950
 pagecache_get_page+0x25a/0x700 mm/filemap.c:1679
 grab_cache_page_write_begin+0x5d/0x90 mm/filemap.c:3277
 mext_page_double_lock fs/ext4/move_extent.c:146 [inline]
 move_extent_per_page fs/ext4/move_extent.c:303 [inline]
 ext4_move_extents+0xfd6/0x1de0 fs/ext4/move_extent.c:673
 ext4_ioctl+0x22ae/0x29b0 fs/ext4/ioctl.c:924
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0x991/0xc60 fs/ioctl.c:696

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7896 Comm: syz-executor.2 Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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