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BUG: KCSAN: data-race in can_receive / can_receive

read-write to 0xffff88800f2c9518 of 8 bytes by interrupt on cpu 0:
 can_receive+0x192/0x1d0 net/can/af_can.c:673
 can_rcv+0x9e/0x170 net/can/af_can.c:696
 __netif_receive_skb_one_core net/core/dev.c:5323 [inline]
 __netif_receive_skb+0x8b/0x1b0 net/core/dev.c:5437
 process_backlog+0x23f/0x3d0 net/core/dev.c:6327
 napi_poll+0x181/0x630 net/core/dev.c:6805
 net_rx_action+0x17a/0x480 net/core/dev.c:6888
 __do_softirq+0x13c/0x2c3 kernel/softirq.c:343
 run_ksoftirqd+0x13/0x20 kernel/softirq.c:650
 smpboot_thread_fn+0x34f/0x520 kernel/smpboot.c:165
 kthread+0x1fd/0x220 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

read-write to 0xffff88800f2c9518 of 8 bytes by interrupt on cpu 1:
 can_receive+0x192/0x1d0 net/can/af_can.c:673
 can_rcv+0x9e/0x170 net/can/af_can.c:696
 __netif_receive_skb_one_core net/core/dev.c:5323 [inline]
 __netif_receive_skb+0x8b/0x1b0 net/core/dev.c:5437
 process_backlog+0x23f/0x3d0 net/core/dev.c:6327
 napi_poll+0x181/0x630 net/core/dev.c:6805
 net_rx_action+0x17a/0x480 net/core/dev.c:6888
 __do_softirq+0x13c/0x2c3 kernel/softirq.c:343
 asm_call_irq_on_stack+0xf/0x20
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0x32/0x40 arch/x86/kernel/irq_64.c:77
 do_softirq kernel/softirq.c:246 [inline]
 __local_bh_enable_ip+0xba/0xd0 kernel/softirq.c:196
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:176 [inline]
 _raw_spin_unlock_bh+0x33/0x40 kernel/locking/spinlock.c:207
 spin_unlock_bh include/linux/spinlock.h:399 [inline]
 batadv_nc_purge_paths+0x26f/0x2c0 net/batman-adv/network-coding.c:467
 batadv_nc_worker+0x163/0x9e0 net/batman-adv/network-coding.c:716
 process_one_work+0x3e1/0x950 kernel/workqueue.c:2275
 worker_thread+0x64a/0xaa0 kernel/workqueue.c:2421
 kthread+0x1fd/0x220 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8 Comm: kworker/u4:0 Not tainted 5.11.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
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