2 Replies Latest reply on Mar 27, 2017 10:27 AM by Intel Corporation

    Broadwell DE x552 SRIOV: Unable to allocate MSI-X interrupts



      I'm running debian Jesse on a broadwell D-1527 with two embedded x552 10Gbe ports.  When I try to enable 63 VFs on each x552 I hit a limit of 55 VFs before get "ixgbevf 0000:02:1f.4: Unable to allocate MSI-X interrupts" errors.  It seems the 55 VFs is a total limit, meaning the total numbers of VFs between the two x552s cannot exceed 55VFs.


      I then tried reducing MSI_X_VF_N from the default value of 0x2 to 0x1.  This resulted in increasing the max to 86 VFs before I got the "Unable to allocate MSI-X interrupts" errors.


      What might be the limiting the maximum MSI_X allocations?