System hang/crash or fence due to I/O stalls with bnx2fc

Issue

• System crash or fence due to I/O stalls with bnx2fc driver. In most cases, this is exposed by an oracle fence by cssdagent or a generic system hang.

PID: 17435  TASK: ffff97b4186da0e0  CPU: 3   COMMAND: "cssdagent"
 #0 [ffff97b3dcbcfac8] machine_kexec at ffffffffb5865704
 #1 [ffff97b3dcbcfb28] __crash_kexec at ffffffffb59209a2
 #2 [ffff97b3dcbcfbf8] crash_kexec at ffffffffb5920a90
 #3 [ffff97b3dcbcfc10] oops_end at ffffffffb5f84798
 #4 [ffff97b3dcbcfc38] no_context at ffffffffb5874ad4
 #5 [ffff97b3dcbcfc88] __bad_area_nosemaphore at ffffffffb5874da2
 #6 [ffff97b3dcbcfcd8] bad_area at ffffffffb5f720fe
 #7 [ffff97b3dcbcfd00] __do_page_fault at ffffffffb5f878b7
 #8 [ffff97b3dcbcfd70] do_page_fault at ffffffffb5f87975
 #9 [ffff97b3dcbcfda0] page_fault at ffffffffb5f83778
    [exception RIP: sysrq_handle_crash+22]
    RIP: ffffffffb5c6d9b6  RSP: ffff97b3dcbcfe58  RFLAGS: 00010246
    RAX: ffffffffb5c6d9a0  RBX: ffffffffb64e55e0  RCX: 0000000000000000
    RDX: 0000000000000000  RSI: ffff97d43f253898  RDI: 0000000000000063
    RBP: ffff97b3dcbcfe58   R8: ffffffffb68018bc   R9: ffff97b438149f40
    R10: 000000000008ed0d  R11: 000000000008ed0c  R12: 0000000000000063
    R13: 0000000000000000  R14: 0000000000000004  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
#10 [ffff97b3dcbcfe60] __handle_sysrq at ffffffffb5c6e1dd
#11 [ffff97b3dcbcfe90] write_sysrq_trigger at ffffffffb5c6e648
#12 [ffff97b3dcbcfea8] proc_reg_write at ffffffffb5ac0930
#13 [ffff97b3dcbcfec8] vfs_write at ffffffffb5a48690
#14 [ffff97b3dcbcff08] sys_write at ffffffffb5a494af
#15 [ffff97b3dcbcff50] system_call_fastpath at ffffffffb5f8cede
    RIP: 00007f2eb1da16fd  RSP: 00007f2eadf506a8  RFLAGS: 00010202
    RAX: 0000000000000001  RBX: 0000000000000000  RCX: 00000000000017ff
    RDX: 0000000000000001  RSI: 00007f2eb772c194  RDI: 000000000000002b
    RBP: 00007f2eadf55060   R8: 0000000000000001   R9: 00007f2e9c000c10
    R10: 00007f2eadf54ae0  R11: 0000000000000293  R12: 0000000000000000
    R13: 0000000000181000  R14: 0000000000000003  R15: 00007f2eadf61700
    ORIG_RAX: 0000000000000001  CS: 0033  SS: 002b