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BUG: KCSAN: data-race in _prb_read_valid / prb_reserve

write to 0xffffffff86efa2e8 of 88 bytes by interrupt on cpu 1:
 prb_reserve+0x6ec/0xad0 kernel/printk/printk_ringbuffer.c:1689
 vprintk_store+0x54e/0x910 kernel/printk/printk.c:2354
 vprintk_emit+0x1a4/0x580 kernel/printk/printk.c:2455
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2494
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2504
 lapbeth_xmit+0x1bd/0x1c0 drivers/net/wan/lapbether.c:-1
 __netdev_start_xmit include/linux/netdevice.h:5457 [inline]
 netdev_start_xmit include/linux/netdevice.h:5466 [inline]
 xmit_one net/core/dev.c:4068 [inline]
 dev_hard_start_xmit+0x10c/0x380 net/core/dev.c:4084
 __dev_queue_xmit+0xbfd/0x1ec0 net/core/dev.c:5088
 dev_queue_xmit include/linux/netdevice.h:3485 [inline]
 x25_send_frame+0xfe/0x130 net/x25/x25_dev.c:193
 x25_transmit_restart_request net/x25/x25_link.c:153 [inline]
 x25_link_control+0x2a9/0x500 net/x25/x25_link.c:102
 x25_receive_data net/x25/x25_dev.c:43 [inline]
 x25_lapb_receive_frame+0x2d6/0x770 net/x25/x25_dev.c:127
 __netif_receive_skb_one_core net/core/dev.c:6435 [inline]
 netif_receive_skb_core+0x122/0x130 net/core/dev.c:6460
 lapbeth_napi_poll+0x42/0x90 drivers/net/wan/lapbether.c:100
 __napi_poll+0x61/0x300 net/core/dev.c:7985
 napi_poll net/core/dev.c:8048 [inline]
 net_rx_action+0x30b/0x7e0 net/core/dev.c:8205
 handle_softirqs+0x109/0x310 kernel/softirq.c:669
 do_softirq+0x46/0x60 kernel/softirq.c:569
 desc_read kernel/printk/printk_ringbuffer.c:499 [inline]
 prb_first_seq kernel/printk/printk_ringbuffer.c:2012 [inline]
 _prb_read_valid+0x636/0x8f0 kernel/printk/printk_ringbuffer.c:2169