System crashed due to list corruption in iscsi_queuecommand.

Issue

• System encountered list corruption and crashed/rebooted.

[1028762.501040] list_add corruption. prev->next should be next (c00020354be673f8), but was c000203963d4f880. (prev=c000203963d4f880).
[1028762.501072] ------------[ cut here ]------------
[1028762.501081] WARNING: CPU: 21 PID: 28260 at lib/list_debug.c:28 __list_add_valid+0x94/0xc0
[1028762.501083] Kernel panic - not syncing: panic_on_warn set ...

[1028762.501147] CPU: 21 PID: 28260 Comm: kdmwork-253:11 Kdump: loaded Not tainted 4.14.0-115.13.1.el7a.ppc64le #1
[1028762.501265] Call Trace:
[1028762.501282] [c000203936db3370] [c000000000c217ac] dump_stack+0xb0/0xf4 (unreliable)
[1028762.501388] [c000203936db33b0] [c000000000138834] panic+0x150/0x33c
[1028762.501464] [c000203936db3440] [c0000000001386e4] panic+0x0/0x33c
[1028762.501547] [c000203936db34d0] [c000000000c204d4] report_bug+0x184/0x220
[1028762.501622] [c000203936db3550] [c00000000002a36c] program_check_exception+0x31c/0x420
[1028762.501702] [c000203936db35d0] [c000000000008e94] program_check_common+0x134/0x140
[1028762.501801] --- interrupt: 700 at __list_add_valid+0x94/0xc0
                     LR = __list_add_valid+0x90/0xc0
[1028762.501926] [c000203936db3920] [c00800000d689d80] iscsi_queuecommand+0x420/0x530 [libiscsi]
[1028762.502044] [c000203936db39e0] [c000000000856444] scsi_dispatch_cmd+0xe4/0x300
[1028762.502131] [c000203936db3a60] [c00000000085a488] scsi_request_fn+0x5e8/0x9e0
[1028762.502241] [c000203936db3b80] [c00000000061c00c] __blk_run_queue+0x6c/0xb0
[1028762.502338] [c000203936db3bb0] [c000000000617638] __elv_add_request+0x1b8/0x540
[1028762.502453] [c000203936db3c40] [c000000000623d4c] blk_insert_cloned_request+0x1cc/0x280
[1028762.502566] [c000203936db3cc0] [c008000011317904] map_tio_request+0x1c4/0x370 [dm_mod]
[1028762.502665] [c000203936db3d60] [c000000000172260] kthread_worker_fn+0xb0/0x290
[1028762.502765] [c000203936db3dc0] [c000000000171618] kthread+0x168/0x1b0
[1028762.502867] [c000203936db3e30] [c00000000000b65c] ret_from_kernel_thread+0x5c/0x80
[1028762.503017] Sending IPI to other CPUs
[1028764.111921] IPI complete
[1028766.209118] kexec: Starting switchover sequence.

• In some cases, system can crash in libiscsi_tcp.c:

PANIC: "kernel BUG at drivers/scsi/libiscsi_tcp.c:979!"

PID: 2426   TASK: c00000079e618700  CPU: 7   COMMAND: "kworker/u32:0"
 #0 [c00000032d07f4a0] crash_kexec at c000000000234ce0
 #1 [c00000032d07f4e0] oops_end at c0000000000284d8
 #2 [c00000032d07f560] _exception at c0000000000299a4
 #3 [c00000032d07f6f0] program_check_exception at c000000000029e6c
 #4 [c00000032d07f770] program_check_common at c000000000008da4
 Program Check [700] exception frame:
 R0:  c00800000cda9690    R1:  c00000032d07fa60    R2:  c00800000ce1c000   
 R3:  c0000007ee418800    R4:  c00000032fd6d16a    R5:  000000000000000a   
 R6:  000000000000a047    R7:  0000000000000000    R8:  00000000001fd998   
 R9:  c0000007ee418898    R10: 0000000000000008    R11: c00800000cdab798   
 R12: c00800000ce10400    R13: c000000007a84d00    R14: c0000000001708a8   
 R15: c00000046decc540    R16: c0000007fd200380    R17: c00000000137c4b0   
 R18: c0000007fd200078    R19: c0000007fd200020    R20: 0000000000000000   
 R21: 0000000000000000    R22: fffffffffffffef7    R23: 0000000000000003   
 R24: c00000079e090408    R25: 0000000000000000    R26: 000000000000b000   
 R27: c00000032fd6d160    R28: c00000079e091420    R29: c00000079e090348   
 R30: c00000079e090348    R31: c0000007ee418800   
 NIP: c00800000ce1044c    MSR: 800000000282b033    OR3: c00800000ce10420
 CTR: c00800000ce10400    LR:  c00800000cda9690    XER: 0000000020040000
 CCR: 0000000028072e48    MQ:  0000000000000001    DAR: 0000000000000000
 DSISR: 0000000000000000     Syscall Result: 0000000000000000
 [NIP  : iscsi_tcp_task_init+76]
 [LR   : iscsi_prep_scsi_cmd_pdu+832]
 #5 [c00000032d07fa60] iscsi_tcp_task_init at c00800000ce1044c [libiscsi_tcp]
 #6 [c00000032d07fad0] iscsi_prep_scsi_cmd_pdu at c00800000cda9690 [libiscsi]  (unreliable)
 #7 [c00000032d07fbc0] iscsi_xmitworker at c00800000cdaa278 [libiscsi]
 #8 [c00000032d07fc80] process_one_work at c000000000163acc
 #9 [c00000032d07fd20] worker_thread at c000000000166aec