KCSAN: data-race in del_nbp / is_eth_port_of_netdev_filter (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 32f741b0 Merge tag 'powerpc-5.10-5' of git://git.kernel.or..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11659aef500000
kernel config: https://syzkaller.appspot.com/x/.config?x=c949fed53798f819
dashboard link: https://syzkaller.appspot.com/bug?extid=4e1dec525802c20dc53d
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project.git 913f6005669cfb590c99865a90bc51ed0983d09d)
CC: [bri...@lists.linux-foundation.org da...@davemloft.net ku...@kernel.org linux-...@vger.kernel.org net...@vger.kernel.org nik...@nvidia.com ro...@nvidia.com]

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4e1dec...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in del_nbp / is_eth_port_of_netdev_filter

read-write to 0xffff88810dc7322c of 4 bytes by task 13613 on cpu 0:
del_nbp+0x723/0x7a0 net/bridge/br_if.c:354
br_dev_delete+0x57/0xe0 net/bridge/br_if.c:375
default_device_exit_batch+0x1ae/0x3d0 net/core/dev.c:11100
ops_exit_list net/core/net_namespace.c:190 [inline]
cleanup_net+0x4cc/0x8a0 net/core/net_namespace.c:604
process_one_work+0x3e1/0x950 kernel/workqueue.c:2272
worker_thread+0x635/0xb90 kernel/workqueue.c:2418
kthread+0x1fd/0x220 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

read to 0xffff88810dc7322c of 4 bytes by task 320 on cpu 1:
is_vlan_dev include/linux/if_vlan.h:74 [inline]
rdma_vlan_dev_real_dev include/rdma/ib_addr.h:266 [inline]
is_eth_port_of_netdev_filter+0x29/0x1a0 drivers/infiniband/core/roce_gid_mgmt.c:157
ib_enum_roce_netdev+0x292/0x310 drivers/infiniband/core/device.c:2263
ib_enum_all_roce_netdevs+0x94/0x100 drivers/infiniband/core/device.c:2292
netdevice_event_work_handler+0xf8/0x200 drivers/infiniband/core/roce_gid_mgmt.c:626
process_one_work+0x3e1/0x950 kernel/workqueue.c:2272
worker_thread+0x635/0xb90 kernel/workqueue.c:2418
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: 320 Comm: kworker/u4:3 Not tainted 5.10.0-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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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.