kernel test robot <l...@intel.com> 于2020年9月10日周四 上午8:19写道：
>
> Greeting,
>
> FYI, we noticed the following commit (built with gcc-9):
>
> commit: db71a2f198fef53a9f710ad5ac475bbdb6aba840 ("[MPTCP][PATCH v2 net 1/2]
> mptcp: fix subflow's local_id issues")
> url:
> https://github.com/0day-ci/linux/commits/Geliang-Tang/mptcp-fix-subflow-s-local_id-remote_id-issues/20200908-105733
> base: https://git.kernel.org/cgit/linux/kernel/git/davem/net.git
> e1f469cd5866499ac40bfdca87411e1c525a10c7
>
> in testcase: kernel-selftests
> version: kernel-selftests-x86_64-e8e8f16e-1_20200807
> with following parameters:
>
> group: kselftests-mptcp
>
> test-description: The kernel contains a set of "self tests" under the
> tools/testing/selftests/ directory. These are intended to be small unit tests
> to exercise individual code paths in the kernel.
> test-url: https://www.kernel.org/doc/Documentation/kselftest.txt
>
>
> on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 8G
>
> caused below changes (please refer to attached dmesg/kmsg for entire
> log/backtrace):
>
>
> +----------------------------------------------------------------------------+------------+------------+
> |
> | e1f469cd58 | db71a2f198 |
> +----------------------------------------------------------------------------+------------+------------+
> | boot_successes
> | 15 | 8 |
> | boot_failures
> | 2 | 9 |
> | Kernel_panic-not_syncing:VFS:Unable_to_mount_root_fs_on_unknown-block(#,#)
> | 2 | |
> | WARNING:inconsistent_lock_state
> | 0 | 9 |
> | inconsistent{SOFTIRQ-ON-W}->{IN-SOFTIRQ-W}usage
> | 0 | 9 |
> | calltrace:asm_call_on_stack
> | 0 | 9 |
> | BUG:sleeping_function_called_from_invalid_context_at_mm/slab.h
> | 0 | 9 |
> +----------------------------------------------------------------------------+------------+------------+
>
>
> If you fix the issue, kindly add following tag
> Reported-by: kernel test robot <l...@intel.com>
>
>
> [ 257.607162] WARNING: inconsistent lock state
> [ 257.609399] 5.9.0-rc3-00371-gdb71a2f198fef #1 Not tainted
> [ 257.611927] --------------------------------
> [ 257.614273] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
> [ 257.617486] kworker/1:2/101 [HC0[0]:SC1[3]:HE1:SE0] takes:
> [ 257.620140] ffffffffae1aaa40 (fs_reclaim){+.?.}-{0:0}, at:
> fs_reclaim_acquire+0x5/0x40
> [ 257.623680] {SOFTIRQ-ON-W} state was registered at:
> [ 257.626250] lock_acquire+0xaf/0x380
> [ 257.628516] fs_reclaim_acquire+0x25/0x40
> [ 257.631071] __kmalloc_node+0x60/0x560
> [ 257.633350] alloc_cpumask_var_node+0x1b/0x40
> [ 257.635850] native_smp_prepare_cpus+0xad/0x292
> [ 257.638255] kernel_init_freeable+0x15a/0x2dd
> [ 257.640847] kernel_init+0xa/0x122
> [ 257.643277] ret_from_fork+0x22/0x30
> [ 257.645510] irq event stamp: 89762
> [ 257.647888] hardirqs last enabled at (89762): [<ffffffffacf08ef0>]
> process_backlog+0x1b0/0x260
> [ 257.651614] hardirqs last disabled at (89761): [<ffffffffacf08f75>]
> process_backlog+0x235/0x260
> [ 257.655368] softirqs last enabled at (89756): [<ffffffffacfb8598>]
> ip_finish_output2+0x258/0xa20
> [ 257.659186] softirqs last disabled at (89757): [<ffffffffad2010d2>]
> asm_call_on_stack+0x12/0x20
> [ 257.663053]
> [ 257.663053] other info that might help us debug this:
> [ 257.667675] Possible unsafe locking scenario:
> [ 257.667675]
> [ 257.672233] CPU0
> [ 257.674229] ----
> [ 257.676375] lock(fs_reclaim);
> [ 257.678563] <Interrupt>
> [ 257.680618] lock(fs_reclaim);
> [ 257.682673]
> [ 257.682673] *** DEADLOCK ***
> [ 257.682673]
> [ 257.687974] 8 locks held by kworker/1:2/101:
> [ 257.690177] #0: ffffa060c7c56938 ((wq_completion)events){+.+.}-{0:0}, at:
> process_one_work+0x1bc/0x5a0
> [ 257.693771] #1: ffffc2fac0197e58
> ((work_completion)(&msk->work)){+.+.}-{0:0}, at: process_one_work+0x1bc/0x5a0
> [ 257.697437] #2: ffffa060dd8258e0 (sk_lock-AF_INET){+.+.}-{0:0}, at:
> mptcp_worker+0x5f/0xac0
> [ 257.700972] #3: ffffa061247e2e20 (k-sk_lock-AF_INET){+.+.}-{0:0}, at:
> inet_stream_connect+0x23/0x60
> [ 257.704558] #4: ffffffffae0c9a40 (rcu_read_lock){....}-{1:2}, at:
> __ip_queue_xmit+0x5/0x600
> [ 257.707957] #5: ffffffffae0c9a40 (rcu_read_lock){....}-{1:2}, at:
> process_backlog+0x75/0x260
> [ 257.711431] #6: ffffffffae0c9a40 (rcu_read_lock){....}-{1:2}, at:
> ip_local_deliver_finish+0x2c/0x120
> [ 257.714689] #7: ffffffffae0c9a40 (rcu_read_lock){....}-{1:2}, at:
> tcp_rcv_state_process+0x17f/0x981
> [ 257.718220]
> [ 257.718220] stack backtrace:
> [ 257.722396] CPU: 1 PID: 101 Comm: kworker/1:2 Not tainted
> 5.9.0-rc3-00371-gdb71a2f198fef #1
> [ 257.726013] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> 1.12.0-1 04/01/2014
> [ 257.729513] Workqueue: events mptcp_worker
> [ 257.732037] Call Trace:
> [ 257.734092] <IRQ>
> [ 257.736155] dump_stack+0x8d/0xc0
> [ 257.738400] mark_lock+0x633/0x7c0
> [ 257.740652] ? print_shortest_lock_dependencies+0x40/0x40
> [ 257.743499] __lock_acquire+0x954/0xaa0
> [ 257.745907] lock_acquire+0xaf/0x380
> [ 257.748288] ? fs_reclaim_acquire+0x5/0x40
> [ 257.750889] ? mptcp_pm_nl_get_local_id+0x232/0x400
> [ 257.753356] fs_reclaim_acquire+0x25/0x40
> [ 257.755986] ? fs_reclaim_acquire+0x5/0x40
> [ 257.758562] kmem_cache_alloc_trace+0x40/0x460
> [ 257.761092] mptcp_pm_nl_get_local_id+0x232/0x400
> [ 257.763793] subflow_init_req+0x1c2/0x3a0
> [ 257.766127] ? inet_reqsk_alloc+0x21/0x140
> [ 257.768560] ? rcu_read_lock_sched_held+0x52/0xa0
> [ 257.771236] ? kmem_cache_alloc+0x3b8/0x460
> [ 257.773656] tcp_conn_request+0x341/0xe60
> [ 257.776117] ? lock_acquire+0xaf/0x380
> [ 257.778486] ? tcp_rcv_state_process+0x17f/0x981
> [ 257.781114] ? tcp_rcv_state_process+0x1e2/0x981
> [ 257.783833] tcp_rcv_state_process+0x1e2/0x981
> [ 257.786417] ? tcp_v4_inbound_md5_hash+0x4c/0x160
> [ 257.789117] tcp_v4_do_rcv+0xb8/0x200
> [ 257.791562] tcp_v4_rcv+0xf94/0x1080
> [ 257.793835] ip_protocol_deliver_rcu+0x2d/0x2a0
> [ 257.796463] ip_local_deliver_finish+0x8c/0x120
> [ 257.799035] ip_local_deliver+0x71/0x220
> [ 257.801471] ? rcu_read_lock_held+0x52/0x60
> [ 257.803973] ip_rcv+0x57/0x200
> [ 257.806218] ? process_backlog+0x75/0x260
> [ 257.808714] __netif_receive_skb_one_core+0x87/0xa0
> [ 257.811476] process_backlog+0xe7/0x260
> [ 257.814050] net_rx_action+0x166/0x480
> [ 257.816877] __do_softirq+0xea/0x4eb
> [ 257.819171] asm_call_on_stack+0x12/0x20
> [ 257.821573] </IRQ>
> [ 257.823513] ? ip_finish_output2+0x258/0xa20
> [ 257.825923] do_softirq_own_stack+0x78/0xa0
> [ 257.828215] do_softirq+0x52/0xa0
> [ 257.830335] __local_bh_enable_ip+0xde/0x100
> [ 257.832834] ip_finish_output2+0x27c/0xa20
> [ 257.835155] ? rcu_read_lock_held+0x52/0x60
> [ 257.837334] ? ip_output+0x7f/0x280
> [ 257.839546] ip_output+0x7f/0x280
> [ 257.841650] __ip_queue_xmit+0x1df/0x600
> [ 257.844052] __tcp_transmit_skb+0xa17/0xc80
> [ 257.846277] tcp_connect+0x4fe/0x600
> [ 257.848421] tcp_v4_connect+0x44e/0x560
> [ 257.850615] __inet_stream_connect+0xc5/0x360
> [ 257.853019] ? __local_bh_enable_ip+0x81/0x100
> [ 257.855302] inet_stream_connect+0x37/0x60
> [ 257.857569] __mptcp_subflow_connect+0x195/0x228
> [ 257.860107] mptcp_pm_create_subflow_or_signal_addr+0x27d/0x5a0
> [ 257.862786] mptcp_worker+0x5e4/0xac0
>
>
> To reproduce:
>
> # build kernel
> cd linux
> cp config-5.9.0-rc3-00371-gdb71a2f198fef .config
> make HOSTCC=gcc-9 CC=gcc-9 ARCH=x86_64 olddefconfig prepare
> modules_prepare bzImage
>
> git clone https://github.com/intel/lkp-tests.git
> cd lkp-tests
> bin/lkp qemu -k <bzImage> job-script # job-script is attached in this
> email
>
Hi,
I had sent out a patch yesterday named "mptcp: fix kmalloc flag in
mptcp_pm_nl_get_local_id", which can fix this issue.
Thanks.
-Geliang
>
>
> Thanks,
> lkp
>
