nvme-tcp: kernel NULL pointer dereference, address: 0000000000000034

[Daniel Wagner]

On Tue, Mar 21, 2023 at 01:10:51PM +0200, Sagi Grimberg wrote:
> Can you verify that you never see a bio-less requests is being polled?

As far I can tell this is not happening anymore. I could trigger just by
doing a

   nvme connect-all -P 2

I've added my annotation again and don't see the combination of

  hxct type = 2 && bio == 0

anymore:

[  503.353236] nvme nvme1: creating 12 I/O queues.
[  503.366038] nvme nvme1: mapped 2/8/2 default/read/poll queues.
[  503.370816] nvme nvme1: q ffff888106944580 rq ffff888140090000 bio ffff88810d1c5e00
[  503.372115] rq ffff888140090000 mq_hctx ffff888104e87000 type 0 bio ffff88810d1c5e00
[  503.372977] nvme nvme1: q ffff888106944580 rq ffff888121820000 bio ffff88810d1c4800
[  503.375439] rq ffff888121820000 mq_hctx ffff888104e80800 type 0 bio ffff88810d1c4800
[  503.376712] nvme nvme1: q ffff888106944580 rq ffff888128790000 bio ffff8881ec613100
[  503.379097] rq ffff888128790000 mq_hctx ffff888104e82000 type 1 bio ffff8881ec613100
[  503.380127] nvme nvme1: q ffff888106944580 rq ffff888129870000 bio ffff8881243c6c00
[  503.382560] rq ffff888129870000 mq_hctx ffff888104e84000 type 1 bio ffff8881243c6c00
[  503.383833] nvme nvme1: q ffff888106944580 rq ffff888105910000 bio ffff8881243c7d00
[  503.383889] rq ffff888105910000 mq_hctx ffff888104e82800 type 1 bio ffff8881243c7d00
[  503.386522] nvme nvme1: q ffff888106944580 rq ffff888104350000 bio ffff8881243c6600
[  503.389771] rq ffff888104350000 mq_hctx ffff888104e83800 type 1 bio ffff8881243c6600
[  503.390783] nvme nvme1: q ffff888106944580 rq ffff888107610000 bio ffff8881243c7c00
[  503.393617] rq ffff888107610000 mq_hctx ffff888104e86000 type 1 bio ffff8881243c7c00
[  503.394612] nvme nvme1: q ffff888106944580 rq ffff888104280000 bio ffff8881243c6200
[  503.397470] rq ffff888104280000 mq_hctx ffff888104e81800 type 1 bio ffff8881243c6200
[  503.398530] nvme nvme1: q ffff888106944580 rq ffff888113e30000 bio ffff8881243c7000
[  503.401462] rq ffff888113e30000 mq_hctx ffff888104e84800 type 1 bio ffff8881243c7000
[  503.402353] nvme nvme1: q ffff888106944580 rq ffff888128940000 bio ffff8881243c7800
[  503.405161] rq ffff888128940000 mq_hctx ffff888104e86800 type 1 bio ffff8881243c7800
[  503.406433] nvme nvme1: q ffff888106944580 rq ffff8881070c0000 bio ffff8881243c7200
[  503.409353] rq ffff8881070c0000 mq_hctx ffff888104e85800 type 2 bio ffff8881243c7200
[  503.410438] nvme nvme1: q ffff888106944580 rq ffff888112210000 bio ffff8881243c7700
[  503.413271] rq ffff888112210000 mq_hctx ffff888104e87800 type 2 bio ffff8881243c7700
[  503.414505] nvme nvme1: q ffff888106e84e30 rq ffff888105fc1400 bio 0000000000000000
[  503.417447] rq ffff888105fc1400 mq_hctx ffff8881417c4800 type 0 bio 0000000000000000
[  503.418401] nvme nvme1: q ffff888106e84e30 rq ffff888105fc1000 bio ffff888111242000
[  503.418410] nvme nvme1: new ctrl: NQN "nqn.io-1", addr 10.161.60.136:4420