dmesg
[13288.113124] <1>
Installing 'msidemo' module
[13288.113165] ENable DEvice 0 
[13288.113564]  PCI_REVISION_ID(0x08) =1 
[13288.113580]  PCI_INTERRUPT_LINE(0x3c) =10b 
[13288.113592]  sub_vend_ID(0x2c)=11792 
[13288.113603]  cap pointer(0x34) =50 
[13288.113611] Irq register 10 
[13288.113620]  0x10640050 0 
[13288.113630]  0x10640054 0 
[13288.113639]  0x10640058 0 
[13288.113648]  0x1064005c 0 
[13288.113658]  dcap 0x50 = 847805 
[13288.113669]  dcap 0x54 = fee0f00c 
[13288.113680]  dcap 0x58 = 0 
[13288.113690]  dcap 0x5c =  4143 
[13288.113701]  dcap 0x60 = 0 
[13288.113711]  dcap 0 
[13288.113722]  status 0x04 = 100002 
[13288.113749]  pci_find_capability =  50 
[13288.114525] pci 0000:01:00.0: irq 96 for MSI/MSI-X
[13288.114585]  MSI ENABLE =  1 
[13288.114600] after msi enable(0x50) =  857805 
[13288.114619] after msi enabled 100406 
[13288.114631]  dcap 0x54 = fee0f00c 
[13288.114642]  dcap 0x58 = 0 
[13288.114652]  dcap 0x5c = 4153 
[13288.114663]  dcap 0x54 = fee0f00c 
[13288.114674]  dcap 0x58 = 0 
[13288.114684]  dcap 0x5c = 4153 
[13288.114694] After MSI enabled 0x10640050 0 
[13288.114704] After MSI enabled 0x10640054 0 
[13288.114714] After MSI enabled 0x10640058 0 
[13288.114723] After MSI enabled 0x1064005c 0 
[13288.114813] Irq register 0 60

---> rmmod msidemo

[13507.448540] (irq_handler):  Called    -------------------> unexpected interrupt is ocur when remove the module.
[13507.449092] <1>Removing 'msidemo' module


[root@localhost msidemo]# cat /proc/interrupts 
            CPU0       CPU1       CPU2       CPU3       
   0:         72          0          0          0   IO-APIC-edge      timer
   4:         14          0          0          0   IO-APIC-edge      serial
   8:          0          0          0          0   IO-APIC-fasteoi   rtc0
   9:          3          0          0          0   IO-APIC-fasteoi   acpi
  23:         53          0          0          0   IO-APIC-fasteoi   ehci_hcd:usb1, mmc0
  87:          0          0          0          0   PCI-MSI-edge      xhci_hcd
  88:          1          0          0          0   PCI-MSI-edge      enp4s0
  89:         16          0          0      23409   PCI-MSI-edge      enp4s0-TxRx-0
  90:         11        382      34794          0   PCI-MSI-edge      enp4s0-TxRx-1
  91:          8       1703       5050          0   PCI-MSI-edge      enp4s0-TxRx-2
  92:          7         68          0      18211   PCI-MSI-edge      enp4s0-TxRx-3
  93:       5520       4084          4          0   PCI-MSI-edge      0000:00:13.0
  94:        109        406       2413      13650   PCI-MSI-edge      i915
  95:         58          0          0          0   PCI-MSI-edge      snd_hda_intel
  96:          0          0          0          0   PCI-MSI-edge      msidemo
 NMI:          2         23         30         25   Non-maskable interrupts
 LOC:     205790     118160     169929     175486   Local timer interrupts
 SPU:          0          0          0          0   Spurious interrupts
 PMI:          2         23         30         25   Performance monitoring interrupts
 IWI:       1506       2135      18034      15726   IRQ work interrupts
 RTR:          0          0          0          0   APIC ICR read retries
 RES:      20395       2904       2252       2720   Rescheduling interrupts
 CAL:       1366      34151      35593      37287   Function call interrupts
 TLB:        255        372        206        397   TLB shootdowns
 TRM:          0          0          0          0   Thermal event interrupts
 THR:          0          0          0          0   Threshold APIC interrupts
 DFR:          0          0          0          0   Deferred Error APIC interrupts
 MCE:          0          0          0          0   Machine check exceptions
 MCP:         45         45         45         45   Machine check polls
 ERR:          0
 MIS:          0
 PIN:          0          0          0          0   Posted-interrupt notification event
 PIW:          0          0          0          0   Posted-interrupt wakeup event
[root@localhost msidemo]#