On one system during power off slot, find card get power on right away. # echo 0 > /sys/bus/pci/slots/1/power pci_hotplug: power_write_file: power = 0 pciehp 0000:16:00.0:pcie004: pciehp_get_power_status: SLOTCTRL a8 value read 11f1 pciehp 0000:16:00.0:pcie004: pciehp_unconfigure_device: domain:bus:dev = 0000:17:00 pci 0000:17:00.0: PME# disabled pci 0000:17:00.0: freeing pci_dev info pciehp 0000:16:00.0:pcie004: pending interrupts 0x0010 from Slot Status pciehp 0000:16:00.0:pcie004: pciehp_power_off_slot: SLOTCTRL a8 write cmd 400 pciehp 0000:16:00.0:pcie004: pending interrupts 0x0108 from Slot Status pciehp 0000:16:00.0:pcie004: Slot(1): Link Down pciehp 0000:16:00.0:pcie004: Slot(1): Link Down event ignored; already powering off pciehp 0000:16:00.0:pcie004: pciehp_green_led_off: SLOTCTRL a8 write cmd 300 pciehp 0000:16:00.0:pcie004: pending interrupts 0x0018 from Slot Status <====== pciehp 0000:16:00.0:pcie004: Slot(1): Card present pciehp 0000:16:00.0:pcie004: pciehp_get_power_status: SLOTCTRL a8 value read 17f1 pciehp 0000:16:00.0:pcie004: pending interrupts 0x0010 from Slot Status pciehp 0000:16:00.0:pcie004: pciehp_power_on_slot: SLOTCTRL a8 write cmd 0 pciehp 0000:16:00.0:pcie004: pciehp_green_led_blink: SLOTCTRL a8 write cmd 200 pciehp 0000:16:00.0:pcie004: pending interrupts 0x0010 from Slot Status pciehp 0000:16:00.0:pcie004: pciehp_check_link_active: lnk_status = f103 pciehp 0000:16:00.0:pcie004: pending interrupts 0x0108 from Slot Status pciehp 0000:16:00.0:pcie004: Slot(1): Link Up ... Somehow PDC bit get set, and during handling interrupt that is caused by CC, that PDC also get handled, and the card get powered on again. In pcie_enable_notification(), we already only enable notification for PDC when attention button is not there. So we can safely add checking in pciehp_isr() to skip that PDC handling. Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx> --- drivers/pci/hotplug/pciehp_hpc.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) Index: linux-2.6/drivers/pci/hotplug/pciehp_hpc.c =================================================================== --- linux-2.6.orig/drivers/pci/hotplug/pciehp_hpc.c +++ linux-2.6/drivers/pci/hotplug/pciehp_hpc.c @@ -618,8 +618,9 @@ static irqreturn_t pciehp_isr(int irq, v present = !!(status & PCI_EXP_SLTSTA_PDS); ctrl_info(ctrl, "Slot(%s): Card %spresent\n", slot_name(slot), present ? "" : "not "); - pciehp_queue_interrupt_event(slot, present ? INT_PRESENCE_ON : - INT_PRESENCE_OFF); + if (!ATTN_BUTTN(ctrl)) + pciehp_queue_interrupt_event(slot, present ? + INT_PRESENCE_ON : INT_PRESENCE_OFF); } /* Check Power Fault Detected */
