IRQ mismatch ifconfig and /proc/interrupts

[Peter Teoh]

I suspect it is a bug, mine is Ubuntu 3.2.0-32 pae kernel, 12.04 32-bit:

cat /proc/interrupts
           CPU0       CPU1       CPU2       CPU3
41:          0          0          0          0   PCI-MSI-edge      eth0

eth0      Link encap:Ethernet  HWaddr 5c:f9:dd:75:54:d8
          Interrupt:41 Base address:0x8000

everything matched.



On Fri, Jul 25, 2014 at 9:58 PM, Oscar Salvador <
osalvador.vilardaga at gmail.com> wrote:

> Hi People! How are you doing?
>
> I'm writting to you because I have a doubt about interrupts.
>
> If I look the interrupts assigned to my eth* with ifconfig, I get:
>
> eth0      Link encap:Ethernet  HWaddr bb:aa:bb:bb:aa:aa
>           Interrupt:20 Memory:f7e00000-f7e20000
>
> eth1      Link encap:Ethernet  HWaddr bb:aa:bb:bb:aa:aa
>           Interrupt:18 Memory:f7d00000-f7d20000
>
> As you can see, my system assigned IRQ-20 and IRQ-18 to eth0 and eth1.
>
> But If i look into /proc/interrupts, I don't have these interrupts:
>
> root at oscar:/home/oscar# cat /proc/interrupts
>            CPU0       CPU1       CPU2       CPU3       CPU4       CPU5
>   CPU6       CPU7
>   0:         15          0          0          0          0          0
>      0          0  IR-IO-APIC-edge      timer
>   8:          0          1          0          0          0          0
>      0          0  IR-IO-APIC-edge      rtc0
>   9:          0          0          0          0          0          2
>      1          0  IR-IO-APIC-fasteoi   acpi
>  16:     191342      27819      25143      21231      19007      18159
>  17183      15717  IR-IO-APIC-fasteoi   ehci_hcd:usb3
>  19:         15          7          0          0          2          9
>      1          4  IR-IO-APIC-fasteoi   firewire_ohci
>  23:       1441         76         61         42        101         55
>     29         23  IR-IO-APIC-fasteoi   ehci_hcd:usb4
>  40:          0          0          0          0          0          0
>      0          0  DMAR_MSI-edge      dmar0
>  41:          0          0          0          0          0          0
>      0          0  DMAR_MSI-edge      dmar1
>  42:          0          0          0          0          0          0
>      0          0  IR-PCI-MSI-edge      xhci_hcd
>  43:      27318       1788       1314       1414       4046       2273
>   2232       2059  IR-PCI-MSI-edge      eth0
>  44:     115244      14686      10096       8738      41559      16021
>  10972      10090  IR-PCI-MSI-edge      ahci
>  45:     197010      19487      45260      14687      43697      29520
>  24546      21590  IR-PCI-MSI-edge      eth1-rx-0
>  46:      27239      20276      18861      14845      54218      17950
>  12907       9765  IR-PCI-MSI-edge      eth1-tx-0
>  47:          0          0          1          0          0          0
>      0          1  IR-PCI-MSI-edge      eth1
>  48:        262        150         78         60        261        249
>    168         47  IR-PCI-MSI-edge      snd_hda_intel
>  49:     857324      80338      67789      59555     682632      90385
>  78616      65048  IR-PCI-MSI-edge      i915
>
>
> As you can see, seems to be that eth1 has IRQ-45 IRQ-46 and IRQ-47, and
> eth0 has IRQ-43.
> I don't understand why ifconfig shows another IRQ.
>
> Is this a normal behaviour? Someone would be so kind to explain me this?
>
> Or maybe throw me some paper that explains this.
>
> thank you very much
> Best Regards
>
> Oscar
>
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>



-- 
Regards,
Peter Teoh
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.kernelnewbies.org/pipermail/kernelnewbies/attachments/20140731/a6db66df/attachment.html