Hi, Leon, Chuck It is still broken even with the hotfix(https://patchwork.kernel.org/patch/11387567/) for 5.4.21. the call stack is almost the same. Feb 20 23:49:53 T630 kernel: Call Trace: Feb 20 23:49:53 T630 kernel: port_pkey_list_insert+0x30/0x1a0 [ib_core] Feb 20 23:49:53 T630 kernel: ? kmem_cache_alloc_trace+0x219/0x230 Feb 20 23:49:53 T630 kernel: ib_security_modify_qp+0x244/0x3b0 [ib_core] Feb 20 23:49:53 T630 kernel: _ib_modify_qp+0x1c0/0x3c0 [ib_core] Feb 20 23:49:53 T630 kernel: ? dma_pool_free+0x24/0xc0 Feb 20 23:49:53 T630 kernel: ipoib_init_qp+0x77/0x190 [ib_ipoib] Feb 20 23:49:53 T630 kernel: ? __mlx4_ib_query_pkey+0xe7/0x110 [mlx4_ib] Feb 20 23:49:53 T630 kernel: ? ib_find_pkey+0x98/0xe0 [ib_core] Feb 20 23:49:53 T630 kernel: ipoib_ib_dev_open_default+0x1a/0x180 [ib_ipoib] Feb 20 23:49:53 T630 kernel: ipoib_ib_dev_open+0x66/0xa0 [ib_ipoib] Feb 20 23:49:53 T630 kernel: ipoib_open+0x44/0x110 [ib_ipoib] Feb 20 23:49:53 T630 kernel: __dev_open+0xcd/0x160 Feb 20 23:49:53 T630 kernel: __dev_change_flags+0x1ad/0x220 Feb 20 23:49:53 T630 kernel: ? __dev_notify_flags+0x95/0xf0 Feb 20 23:49:53 T630 kernel: dev_change_flags+0x21/0x60 Feb 20 23:49:53 T630 kernel: do_setlink+0x320/0xf00 Feb 20 23:49:53 T630 kernel: ? __nla_validate_parse+0x51/0x840 Feb 20 23:49:53 T630 kernel: ? xas_load+0x8/0x80 Feb 20 23:49:53 T630 kernel: ? __update_load_avg_cfs_rq+0x1d5/0x2c0 Feb 20 23:49:53 T630 kernel: ? cpumask_next+0x17/0x20 Feb 20 23:49:53 T630 kernel: ? __snmp6_fill_stats64.isra.56+0x6b/0x110 Feb 20 23:49:53 T630 kernel: ? __nla_validate_parse+0x51/0x840 Feb 20 23:49:53 T630 kernel: __rtnl_newlink+0x53d/0x890 Feb 20 23:49:53 T630 kernel: ? __nla_reserve+0x38/0x50 Feb 20 23:49:53 T630 kernel: ? __nla_put+0xc/0x20 Feb 20 23:49:53 T630 kernel: ? __nla_reserve+0x38/0x50 Feb 20 23:49:53 T630 kernel: ? __nla_put+0xc/0x20 Feb 20 23:49:53 T630 kernel: ? nla_put+0x2f/0x40 Feb 20 23:49:53 T630 kernel: ? __nla_reserve+0x38/0x50 Feb 20 23:49:53 T630 kernel: ? __nla_put+0xc/0x20 Feb 20 23:49:53 T630 kernel: ? nla_put+0x2f/0x40 Feb 20 23:49:53 T630 kernel: ? rt6_fill_node+0x2d4/0x850 Feb 20 23:49:53 T630 kernel: ? _cond_resched+0x15/0x30 Feb 20 23:49:53 T630 kernel: ? kmem_cache_alloc_trace+0x1c9/0x230 Feb 20 23:49:53 T630 kernel: rtnl_newlink+0x43/0x60 Feb 20 23:49:53 T630 kernel: rtnetlink_rcv_msg+0x2b1/0x360 Feb 20 23:49:53 T630 kernel: ? __kmalloc_node_track_caller+0x241/0x300 Feb 20 23:49:53 T630 kernel: ? _cond_resched+0x15/0x30 Feb 20 23:49:53 T630 kernel: ? rtnl_calcit.isra.32+0x110/0x110 Feb 20 23:49:53 T630 kernel: netlink_rcv_skb+0x49/0x110 Feb 20 23:49:53 T630 kernel: netlink_unicast+0x191/0x220 Feb 20 23:49:53 T630 kernel: netlink_sendmsg+0x21d/0x3f0 Feb 20 23:49:53 T630 kernel: sock_sendmsg+0x5b/0x60 Feb 20 23:49:53 T630 kernel: ____sys_sendmsg+0x1eb/0x260 Feb 20 23:49:53 T630 kernel: ? copy_msghdr_from_user+0xdb/0x160 Feb 20 23:49:53 T630 kernel: ___sys_sendmsg+0x7c/0xc0 Feb 20 23:49:53 T630 kernel: ? do_filp_open+0xa7/0x100 Feb 20 23:49:53 T630 kernel: ? netdev_run_todo+0x5e/0x290 Feb 20 23:49:53 T630 kernel: ? list_lru_add+0xb7/0x1d0 Feb 20 23:49:53 T630 kernel: __sys_sendmsg+0x57/0xa0 Feb 20 23:49:53 T630 kernel: do_syscall_64+0x5b/0x180 Feb 20 23:49:53 T630 kernel: entry_SYSCALL_64_after_hwframe+0x44/0xa9 This card have 2 port, and port 1 is set as InfiniBand, port 2 is set as Ethernet. # ibstat CA 'mlx4_0' CA type: MT4099 Number of ports: 2 Firmware version: 2.42.5000 Hardware version: 1 Node GUID: 0xe41d2d03007b4080 System image GUID: 0xe41d2d03007b4083 Port 1: State: Down Physical state: Polling Rate: 10 Base lid: 0 LMC: 0 SM lid: 0 Capability mask: 0x02594868 Port GUID: 0xe41d2d03007b4081 Link layer: InfiniBand Port 2: State: Down Physical state: Disabled Rate: 40 Base lid: 0 LMC: 0 SM lid: 0 Capability mask: 0x00010000 Port GUID: 0xe61d2dfffe7b4082 Link layer: Ethernet Best Regards 王玉贵 2020/02/21 > On Thu, Feb 20, 2020 at 08:57:29AM -0500, Chuck Lever wrote: > > Hello! > > > > Thanks for your bug report. > > > > > > > On Feb 19, 2020, at 10:22 PM, Wang Yugui <wangyugui@xxxxxxxxxxxx> wrote: > > > > > > Hi, chuck.lever > > > > > > a bug(BUG: kernel NULL pointer dereference) of ib or mlx happened in 5.4.21 but not in 5.4.20. > > > > > > maybe some releationship to xprtrdma-fix-dma-scatter-gather-list-mapping-imbalance.patch > > > > I don't see an obvious connection to fix-dma-scatter-gather-list-mapping-imbalance. > > The backtrace below is through IPoIB code paths. Those have nothing to do with > > NFS/RDMA, which is the only ULP code that is changed by my commit. > > > > > > > maybe the info is useful. > > > > I'm copying linux-rdma for a bigger set of eyeballs. > > > > My knee-jerk recommendation is that if you have a reliable reproducer, try "git bisect" > > between .20 and .21 to nail down a specific commit where the BUG starts to occur. > > No need to bisect, it is me who broke. > The fix is already accepted, but not yet merged. > https://patchwork.kernel.org/patch/11387567/ > > Thanks -------------------------------------- 北京京垓科技有限公司 王玉贵 wangyugui@xxxxxxxxxxxx 电话：+86-136-71123776
