Hi Alan, Recently, I'm debugging this issue (the same symptom described by Don) on my server. Fortunately, the issue was fixed by applying your patch posted in this email thread. Just checked the latest kernel (3.7.4) and the mainline (3.8-rc4), the patch was not included in those kernels. Do you have any schedule to submit the patch to the upstream? Thanks in advance. The list of the allocated IRQ (uhci_hcd used the shared interrupt) on my server: CPU0 CPU1 CPU2 CPU3 CPU4 CPU5 CPU6 CPU7 0: 120 0 0 0 0 0 0 0 IR-IO-APIC-edge timer 1: 2 0 0 0 0 0 0 0 IR-IO-APIC-edge i8042 3: 2 0 0 0 0 0 0 0 IR-IO-APIC-edge 4: 1 0 0 0 0 0 0 0 IR-IO-APIC-edge 8: 1 0 0 0 0 0 0 0 IR-IO-APIC-edge rtc0 9: 0 0 0 0 0 0 0 0 IR-IO-APIC-fasteoi acpi 12: 4 0 0 0 0 0 0 0 IR-IO-APIC-edge i8042 16: 1187 0 0 0 0 0 0 0 IR-IO-APIC-fasteoi uhci_hcd:usb3, hpilo 20: 1385 0 0 0 0 0 0 0 IR-IO-APIC-fasteoi ehci_hcd:usb2 21: 167 0 0 0 0 0 0 0 IR-IO-APIC-fasteoi ehci_hcd:usb1 -- Adrian -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html