On Sat, May 7, 2022 at 9:29 AM Jason Gunthorpe <jgg@xxxxxxxxxx> wrote:
>
> On Sat, May 07, 2022 at 08:29:31AM +0800, Yanjun Zhu wrote:
>
> > > If I try to run the SRP test 002 with the soft-RoCE driver, the
> > > following appears:
> > >
> > > [ 749.901966] ================================
> > > [ 749.903638] WARNING: inconsistent lock state
> > > [ 749.905376] 5.18.0-rc5-dbg+ #1 Not tainted
> > > [ 749.907039] --------------------------------
> > > [ 749.908699] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
> > > [ 749.910646] ksoftirqd/5/40 [HC0[0]:SC1[1]:HE0:SE0] takes:
> > > [ 749.912499] ffff88818244d350 (&xa->xa_lock#14){+.?.}-{2:2}, at:
> > > rxe_pool_get_index+0x73/0x170 [rdma_rxe]
> > > [ 749.914691] {SOFTIRQ-ON-W} state was registered at:
> > > [ 749.916648] __lock_acquire+0x45b/0xce0
> > > [ 749.918599] lock_acquire+0x18a/0x450
> > > [ 749.920480] _raw_spin_lock+0x34/0x50
> > > [ 749.922580] __rxe_add_to_pool+0xcc/0x140 [rdma_rxe]
> > > [ 749.924583] rxe_alloc_pd+0x2d/0x40 [rdma_rxe]
> > > [ 749.926394] __ib_alloc_pd+0xa3/0x270 [ib_core]
> > > [ 749.928579] ib_mad_port_open+0x44a/0x790 [ib_core]
> > > [ 749.930640] ib_mad_init_device+0x8e/0x110 [ib_core]
> > > [ 749.932495] add_client_context+0x26a/0x330 [ib_core]
> > > [ 749.934302] enable_device_and_get+0x169/0x2b0 [ib_core]
> > > [ 749.936217] ib_register_device+0x26f/0x330 [ib_core]
> > > [ 749.938020] rxe_register_device+0x1b4/0x1d0 [rdma_rxe]
> > > [ 749.939794] rxe_add+0x8c/0xc0 [rdma_rxe]
> > > [ 749.941552] rxe_net_add+0x5b/0x90 [rdma_rxe]
> > > [ 749.943356] rxe_newlink+0x71/0x80 [rdma_rxe]
> > > [ 749.945182] nldev_newlink+0x21e/0x370 [ib_core]
> > > [ 749.946917] rdma_nl_rcv_msg+0x200/0x410 [ib_core]
> > > [ 749.948657] rdma_nl_rcv+0x140/0x220 [ib_core]
> > > [ 749.950373] netlink_unicast+0x307/0x460
> > > [ 749.952063] netlink_sendmsg+0x422/0x750
> > > [ 749.953672] __sys_sendto+0x1c2/0x250
> > > [ 749.955281] __x64_sys_sendto+0x7f/0x90
> > > [ 749.956849] do_syscall_64+0x35/0x80
> > > [ 749.958353] entry_SYSCALL_64_after_hwframe+0x44/0xae
> > > [ 749.959942] irq event stamp: 1411849
> > > [ 749.961517] hardirqs last enabled at (1411848): [<ffffffff810cdb28>]
> > > __local_bh_enable_ip+0x88/0xf0
> > > [ 749.963338] hardirqs last disabled at (1411849): [<ffffffff81ebf24d>]
> > > _raw_spin_lock_irqsave+0x5d/0x60
> > > [ 749.965214] softirqs last enabled at (1411838): [<ffffffff82200467>]
> > > __do_softirq+0x467/0x6e1
> > > [ 749.967027] softirqs last disabled at (1411843): [<ffffffff810cd947>]
> > > run_ksoftirqd+0x37/0x60
> > To this, Please use this patch series
> > news://nntp.lore.kernel.org:119/20220422194416.983549-1-yanjun.zhu@xxxxxxxxx
>
> No, that is the wrong fix for this. This is mismatched lock modes with
> the lookup path in the BH, the fix is to consistently use BH locking
> with the xarray everwhere or to use RCU. I'm expecting to go with
> Bob's RCU patch.
I delved into the above calltrace. It is the same with the problem in
the link https://www.spinics.net/lists/linux-rdma/msg109875.html
So IMHO, the fix in this link
https://patchwork.kernel.org/project/linux-rdma/patch/20220422194416.983549-1-yanjun.zhu@xxxxxxxxx/
should fix this problem.
And if we want to use BH, it is very possible that the problem in the
link https://patchwork.kernel.org/project/linux-rdma/patch/20220210073655.42281-4-guoqing.jiang@xxxxxxxxx/
will occur.
And to the RCU patch series in the link
https://patchwork.kernel.org/project/linux-rdma/patch/20220421014042.26985-2-rpearsonhpe@xxxxxxxxx/
I also delved into this patch series. And I found that an atomic
problem will occur if we apply RCU patches onto V5.18-rc5.
And because of the atomic problem, I can not verify that this RCU
patches can fix this problem currently.
Zhu Yanjun
>
> We still need a proper patch for the AH problem.
>
> Jason
