I think this is new since I upgraded to 14.2.6. kworker/7:3 100% [@~]# echo l > /proc/sysrq-trigger [Tue Jan 14 10:05:08 2020] CPU: 7 PID: 2909400 Comm: kworker/7:0 Not tainted 3.10.0-1062.4.3.el7.x86_64 #1 [Tue Jan 14 10:05:08 2020] Workqueue: ceph-msgr ceph_con_workfn [libceph] [Tue Jan 14 10:05:08 2020] task: ffffa0d2cb9db150 ti: ffffa0d3040f0000 task.ti: ffffa0d3040f0000 [Tue Jan 14 10:05:08 2020] RIP: 0010:[<ffffffffb0192e7e>] [<ffffffffb0192e7e>] generic_swap+0x1e/0x30 [Tue Jan 14 10:05:08 2020] RSP: 0018:ffffa0d3040f3a20 EFLAGS: 00000206 [Tue Jan 14 10:05:08 2020] RAX: 0000000000000072 RBX: 0000000000000060 RCX: 0000000000000072 [Tue Jan 14 10:05:08 2020] RDX: 0000000000000006 RSI: ffffa0c788914a7a RDI: ffffa0c788914a42 [Tue Jan 14 10:05:08 2020] RBP: ffffa0d3040f3a20 R08: 0000000000000028 R09: 0000000000000016 [Tue Jan 14 10:05:08 2020] R10: 0000000000000036 R11: ffffe94984224500 R12: ffffa0c788914a40 [Tue Jan 14 10:05:08 2020] R13: ffffffffc08d7da0 R14: ffffa0c788914a18 R15: ffffa0c788914a78 [Tue Jan 14 10:05:08 2020] FS: 0000000000000000(0000) GS:ffffa0d2cfbc0000(0000) knlGS:0000000000000000 [Tue Jan 14 10:05:08 2020] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [Tue Jan 14 10:05:08 2020] CR2: 000055f0404d5e40 CR3: 0000001813010000 CR4: 00000000000627e0 [Tue Jan 14 10:05:08 2020] Call Trace: [Tue Jan 14 10:05:08 2020] [<ffffffffb0193055>] sort+0x1c5/0x260 [Tue Jan 14 10:05:08 2020] [<ffffffffb0192e60>] ? u32_swap+0x10/0x10 [Tue Jan 14 10:05:08 2020] [<ffffffffc08d807b>] build_snap_context+0x12b/0x290 [ceph] [Tue Jan 14 10:05:08 2020] [<ffffffffc08d820c>] rebuild_snap_realms+0x2c/0x90 [ceph] [Tue Jan 14 10:05:08 2020] [<ffffffffc08d822b>] rebuild_snap_realms+0x4b/0x90 [ceph] [Tue Jan 14 10:05:08 2020] [<ffffffffc08d91fc>] ceph_update_snap_trace+0x3ec/0x530 [ceph] [Tue Jan 14 10:05:08 2020] [<ffffffffc08e2239>] handle_reply+0x359/0xc60 [ceph] [Tue Jan 14 10:05:08 2020] [<ffffffffc08e48ba>] dispatch+0x11a/0xb00 [ceph] [Tue Jan 14 10:05:08 2020] [<ffffffffb042e56a>] ? kernel_recvmsg+0x3a/0x50 [Tue Jan 14 10:05:08 2020] [<ffffffffc05fcff4>] try_read+0x544/0x1300 [libceph] [Tue Jan 14 10:05:08 2020] [<ffffffffafee13ce>] ? account_entity_dequeue+0xae/0xd0 [Tue Jan 14 10:05:08 2020] [<ffffffffafee4d5c>] ? dequeue_entity+0x11c/0x5e0 [Tue Jan 14 10:05:08 2020] [<ffffffffb042e417>] ? kernel_sendmsg+0x37/0x50 [Tue Jan 14 10:05:08 2020] [<ffffffffc05fdfb4>] ceph_con_workfn+0xe4/0x1530 [libceph] [Tue Jan 14 10:05:08 2020] [<ffffffffb057f568>] ? __schedule+0x448/0x9c0 [Tue Jan 14 10:05:08 2020] [<ffffffffafebe21f>] process_one_work+0x17f/0x440 [Tue Jan 14 10:05:08 2020] [<ffffffffafebf336>] worker_thread+0x126/0x3c0 [Tue Jan 14 10:05:08 2020] [<ffffffffafebf210>] ? manage_workers.isra.26+0x2a0/0x2a0 [Tue Jan 14 10:05:08 2020] [<ffffffffafec61f1>] kthread+0xd1/0xe0 [Tue Jan 14 10:05:08 2020] [<ffffffffafec6120>] ? insert_kthread_work+0x40/0x40 [Tue Jan 14 10:05:08 2020] [<ffffffffb058cd37>] ret_from_fork_nospec_begin+0x21/0x21 [Tue Jan 14 10:05:08 2020] [<ffffffffafec6120>] ? insert_kthread_work+0x40/0x40 [Tue Jan 14 10:05:08 2020] CPU: 7 PID: 2909400 Comm: kworker/7:0 Not tainted 3.10.0-1062.4.3.el7.x86_64 #1 [Tue Jan 14 10:05:08 2020] Workqueue: ceph-msgr ceph_con_workfn [libceph] [Tue Jan 14 10:05:08 2020] task: ffffa0d2cb9db150 ti: ffffa0d3040f0000 task.ti: ffffa0d3040f0000 [Tue Jan 14 10:05:08 2020] RIP: 0010:[<ffffffffb0192200>] [<ffffffffb0192200>] __x86_indirect_thunk_rax+0x0/0x20 [Tue Jan 14 10:05:08 2020] RSP: 0018:ffffa0d3040f3a28 EFLAGS: 00000286 [Tue Jan 14 10:05:08 2020] RAX: ffffffffb0192e60 RBX: 0000000000000010 RCX: 0000000000000010 [Tue Jan 14 10:05:08 2020] RDX: 0000000000000008 RSI: ffffa0d0e108b828 RDI: ffffa0d0e108b818 [Tue Jan 14 10:05:08 2020] RBP: ffffa0d3040f3a98 R08: 0000000000000000 R09: 0000000000000016 [Tue Jan 14 10:05:08 2020] R10: 0000000000000036 R11: ffffe949a9842280 R12: ffffa0d0e108b818 [Tue Jan 14 10:05:08 2020] R13: ffffffffc08d7da0 R14: ffffa0d0e108b818 R15: ffffa0d0e108b828 [Tue Jan 14 10:05:08 2020] FS: 0000000000000000(0000) GS:ffffa0d2cfbc0000(0000) knlGS:0000000000000000 [Tue Jan 14 10:05:08 2020] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [Tue Jan 14 10:05:08 2020] CR2: 000055f0404d5e40 CR3: 0000001813010000 CR4: 00000000000627e0 [Tue Jan 14 10:05:08 2020] Call Trace: [Tue Jan 14 10:05:08 2020] [<ffffffffb0193055>] ? sort+0x1c5/0x260 [Tue Jan 14 10:05:08 2020] [<ffffffffb0192e60>] ? u32_swap+0x10/0x10 [Tue Jan 14 10:05:08 2020] [<ffffffffc08d807b>] build_snap_context+0x12b/0x290 [ceph] [Tue Jan 14 10:05:08 2020] [<ffffffffc08d820c>] rebuild_snap_realms+0x2c/0x90 [ceph] [Tue Jan 14 10:05:08 2020] [<ffffffffc08d822b>] rebuild_snap_realms+0x4b/0x90 [ceph] [Tue Jan 14 10:05:08 2020] [<ffffffffc08d91fc>] ceph_update_snap_trace+0x3ec/0x530 [ceph] [Tue Jan 14 10:05:08 2020] [<ffffffffc08e2239>] handle_reply+0x359/0xc60 [ceph] [Tue Jan 14 10:05:08 2020] [<ffffffffc08e48ba>] dispatch+0x11a/0xb00 [ceph] [Tue Jan 14 10:05:08 2020] [<ffffffffb042e56a>] ? kernel_recvmsg+0x3a/0x50 [Tue Jan 14 10:05:08 2020] [<ffffffffc05fcff4>] try_read+0x544/0x1300 [libceph] [Tue Jan 14 10:05:08 2020] [<ffffffffafee13ce>] ? account_entity_dequeue+0xae/0xd0 [Tue Jan 14 10:05:08 2020] [<ffffffffafee4d5c>] ? dequeue_entity+0x11c/0x5e0 [Tue Jan 14 10:05:08 2020] [<ffffffffb042e417>] ? kernel_sendmsg+0x37/0x50 [Tue Jan 14 10:05:08 2020] [<ffffffffc05fdfb4>] ceph_con_workfn+0xe4/0x1530 [libceph] [Tue Jan 14 10:05:08 2020] [<ffffffffb057f568>] ? __schedule+0x448/0x9c0 [Tue Jan 14 10:05:08 2020] [<ffffffffafebe21f>] process_one_work+0x17f/0x440 [Tue Jan 14 10:05:08 2020] [<ffffffffafebf336>] worker_thread+0x126/0x3c0 [Tue Jan 14 10:05:08 2020] [<ffffffffafebf210>] ? manage_workers.isra.26+0x2a0/0x2a0 [Tue Jan 14 10:05:08 2020] [<ffffffffafec61f1>] kthread+0xd1/0xe0 [Tue Jan 14 10:05:08 2020] [<ffffffffafec6120>] ? insert_kthread_work+0x40/0x40 [Tue Jan 14 10:05:08 2020] [<ffffffffb058cd37>] ret_from_fork_nospec_begin+0x21/0x21 [Tue Jan 14 10:05:08 2020] [<ffffffffafec6120>] ? insert_kthread_work+0x40/0x40