On Sun, Apr 26, 2020 at 06:43:13AM -0700, syzbot wrote: > Hello, > > syzbot found the following crash on: > > HEAD commit: b9663b7c net: stmmac: Enable SERDES power up/down sequence > git tree: net > console output: https://syzkaller.appspot.com/x/log.txt?x=166bf717e00000 > kernel config: https://syzkaller.appspot.com/x/.config?x=5d351a1019ed81a2 > dashboard link: https://syzkaller.appspot.com/bug?extid=4088ed905e4ae2b0e13b > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > > Unfortunately, I don't have any reproducer for this crash yet. > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+4088ed905e4ae2b0e13b@xxxxxxxxxxxxxxxxxxxxxxxxx > > rdma_rxe: ignoring netdev event = 10 for netdevsim0 > infiniband yz2: set down > WARNING: CPU: 0 PID: 22753 at drivers/infiniband/core/device.c:1565 ib_unregister_device_queued+0x122/0x160 drivers/infiniband/core/device.c:1565 The only thing I can think of for this is that ib_register_driver() is racing with __ib_unregister_device() and took the special error unwind. I suspect this is not a bug, but over complexity triggering a pre-condition WARN_ON.. Maybe the solution is to swap the dealloc_driver = NULL for some other flag. Jason
