syzbot

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BUG: KCSAN: data-race in __dev_open / is_ndev_for_default_gid_filter

write to 0xffff8880403eb228 of 4 bytes by task 24102 on cpu 1:
 __dev_open+0x2c9/0x3a0 net/core/dev.c:1535
 dev_open+0x54/0x190 net/core/dev.c:1564
 bond_enslave+0xa3e/0x2d00 drivers/net/bonding/bond_main.c:1752
 do_set_master net/core/rtnetlink.c:2519 [inline]
 do_setlink+0x87d/0x2260 net/core/rtnetlink.c:2715
 __rtnl_newlink net/core/rtnetlink.c:3376 [inline]
 rtnl_newlink+0xe4e/0x12e0 net/core/rtnetlink.c:3491
 rtnetlink_rcv_msg+0x729/0x7c0 net/core/rtnetlink.c:5553
 netlink_rcv_skb+0x13e/0x240 net/netlink/af_netlink.c:2494
 rtnetlink_rcv+0x18/0x20 net/core/rtnetlink.c:5571
 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
 netlink_unicast+0x5fc/0x6c0 net/netlink/af_netlink.c:1330
 netlink_sendmsg+0x6f8/0x7c0 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 __sys_sendto+0x2a8/0x370 net/socket.c:1975
 __do_sys_sendto net/socket.c:1987 [inline]
 __se_sys_sendto net/socket.c:1983 [inline]
 __x64_sys_sendto+0x74/0x90 net/socket.c:1983
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8880403eb228 of 4 bytes by task 11199 on cpu 0:
 netif_is_bond_master include/linux/netdevice.h:4929 [inline]
 is_ndev_for_default_gid_filter+0x33/0x130 drivers/infiniband/core/roce_gid_mgmt.c:219
 ib_enum_roce_netdev+0x292/0x310 drivers/infiniband/core/device.c:2287
 ib_enum_all_roce_netdevs+0x94/0x100 drivers/infiniband/core/device.c:2316
 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:296

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 11199 Comm: kworker/u4:6 Not tainted 5.11.0-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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