syzbot

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BUG: KCSAN: data-race in __dev_change_flags / is_upper_ndev_bond_master_filter

write to 0xffff88803be2f0c0 of 4 bytes by task 27440 on cpu 1:
 __dev_change_flags+0xa1/0x3f0 net/core/dev.c:8660
 rtnl_configure_link+0xc2/0x150 net/core/rtnetlink.c:3125
 __rtnl_newlink net/core/rtnetlink.c:3451 [inline]
 rtnl_newlink+0xec5/0x1310 net/core/rtnetlink.c:3491
 rtnetlink_rcv_msg+0x728/0x7c0 net/core/rtnetlink.c:5553
 netlink_rcv_skb+0x13e/0x240 net/netlink/af_netlink.c:2502
 rtnetlink_rcv+0x18/0x20 net/core/rtnetlink.c:5571
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x5fc/0x6c0 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0x6f8/0x7c0 net/netlink/af_netlink.c:1927
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg net/socket.c:674 [inline]
 ____sys_sendmsg+0x360/0x4d0 net/socket.c:2350
 ___sys_sendmsg net/socket.c:2404 [inline]
 __sys_sendmsg+0x1ed/0x270 net/socket.c:2433
 __do_sys_sendmsg net/socket.c:2442 [inline]
 __se_sys_sendmsg net/socket.c:2440 [inline]
 __x64_sys_sendmsg+0x42/0x50 net/socket.c:2440
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88803be2f0c0 of 4 bytes by task 24 on cpu 0:
 netif_is_bond_master include/linux/netdevice.h:4978 [inline]
 is_upper_ndev_bond_master_filter+0x27/0xb0 drivers/infiniband/core/roce_gid_mgmt.c:274
 ib_enum_roce_netdev+0x292/0x310 drivers/infiniband/core/device.c:2301
 ib_enum_all_roce_netdevs+0x94/0x100 drivers/infiniband/core/device.c:2330
 netdevice_event_work_handler+0xf8/0x200 drivers/infiniband/core/roce_gid_mgmt.c:626
 process_one_work+0x3e1/0x950 kernel/workqueue.c:2275
 worker_thread+0x616/0xa70 kernel/workqueue.c:2421
 kthread+0x20b/0x230 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 24 Comm: kworker/u4:1 Tainted: G        W         5.12.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: gid-cache-wq netdevice_event_work_handler
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