From: Zheng Xiang Date: Mon, 3 Dec 2018 15:05:17 +0800 Subject: pcie: set link state inactive/active after hot unplug/plug When VM boots from the latest version of linux kernel, after hot-unpluging virtio-blk disks which are hotplugged into pcie-root-port, the VM's dmesg log shows: [ 151.046242] pciehp 0000:00:05.0:pcie004: pending interrupts 0x0001 from Slot Status [ 151.046365] pciehp 0000:00:05.0:pcie004: Slot(0-3): Attention button pressed [ 151.046369] pciehp 0000:00:05.0:pcie004: Slot(0-3): Powering off due to button press [ 151.046420] pciehp 0000:00:05.0:pcie004: pending interrupts 0x0010 from Slot Status [ 151.046425] pciehp 0000:00:05.0:pcie004: pciehp_green_led_blink: SLOTCTRL a8 write cmd 200 [ 151.046464] pciehp 0000:00:05.0:pcie004: pending interrupts 0x0010 from Slot Status [ 151.046468] pciehp 0000:00:05.0:pcie004: pciehp_set_attention_status: SLOTCTRL a8 write cmd c0 [ 156.163421] pciehp 0000:00:05.0:pcie004: pciehp_get_power_status: SLOTCTRL a8 value read 2f1 [ 156.163427] pciehp 0000:00:05.0:pcie004: pciehp_unconfigure_device: domain:bus:dev = 0000:06:00 [ 156.198736] pciehp 0000:00:05.0:pcie004: pending interrupts 0x0010 from Slot Status [ 156.198772] pciehp 0000:00:05.0:pcie004: pciehp_power_off_slot: SLOTCTRL a8 write cmd 400 [ 157.224124] pciehp 0000:00:05.0:pcie004: pending interrupts 0x0018 from Slot Status [ 157.224194] pciehp 0000:00:05.0:pcie004: pciehp_green_led_off: SLOTCTRL a8 write cmd 300 [ 157.224220] pciehp 0000:00:05.0:pcie004: pciehp_check_link_active: lnk_status = 2011 [ 157.224223] pciehp 0000:00:05.0:pcie004: Slot(0-3): Link Up [ 157.224233] pciehp 0000:00:05.0:pcie004: pciehp_get_power_status: SLOTCTRL a8 value read 7f1 [ 157.224281] pciehp 0000:00:05.0:pcie004: pending interrupts 0x0010 from Slot Status [ 157.224285] pciehp 0000:00:05.0:pcie004: pciehp_power_on_slot: SLOTCTRL a8 write cmd 0 [ 157.224300] pciehp 0000:00:05.0:pcie004: __pciehp_link_set: lnk_ctrl = 0 [ 157.224336] pciehp 0000:00:05.0:pcie004: pending interrupts 0x0010 from Slot Status [ 157.224339] pciehp 0000:00:05.0:pcie004: pciehp_green_led_blink: SLOTCTRL a8 write cmd 200 [ 159.739294] pci 0000:06:00.0 id reading try 50 times with interval 20 ms to get ffffffff [ 159.739315] pciehp 0000:00:05.0:pcie004: pciehp_check_link_status: lnk_status = 2011 [ 159.739318] pciehp 0000:00:05.0:pcie004: Failed to check link status [ 159.739371] pciehp 0000:00:05.0:pcie004: pending interrupts 0x0010 from Slot Status [ 159.739394] pciehp 0000:00:05.0:pcie004: pciehp_power_off_slot: SLOTCTRL a8 write cmd 400 [ 160.771426] pciehp 0000:00:05.0:pcie004: pending interrupts 0x0010 from Slot Status [ 160.771452] pciehp 0000:00:05.0:pcie004: pciehp_green_led_off: SLOTCTRL a8 write cmd 300 [ 160.771495] pciehp 0000:00:05.0:pcie004: pending interrupts 0x0010 from Slot Status [ 160.771499] pciehp 0000:00:05.0:pcie004: pciehp_set_attention_status: SLOTCTRL a8 write cmd 40 [ 160.771535] pciehp 0000:00:05.0:pcie004: pending interrupts 0x0010 from Slot Status [ 160.771539] pciehp 0000:00:05.0:pcie004: pciehp_green_led_off: SLOTCTRL a8 write cmd 300 After analyzing the log information, it seems that qemu doesn't change the Link Status from active to inactive after hot-unplug. This results in the abnormal log after the linux kernel commit d331710ea78fea merged. Furthermore, If I hotplug the same virtio-blk disk after hot-unplug, the virtio-blk would turn on and then back off. So this patch set the Link Status inactive after hot-unplug and active after hot-plug. Signed-off-by: Zheng Xiang Signed-off-by: Zheng Xiang Cc: Wang Haibin Cc: qemu-stable@nongnu.org Reviewed-by: Marcel Apfelbaum Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin (cherry picked from commit 2f2b18f60bf17453b4c01197a9316615a3c1f1de) Signed-off-by: Bruce Rogers --- hw/pci/pcie.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c index 6c91bd44a0..66b73b87c8 100644 --- a/hw/pci/pcie.c +++ b/hw/pci/pcie.c @@ -345,6 +345,10 @@ void pcie_cap_slot_hotplug_cb(HotplugHandler *hotplug_dev, DeviceState *dev, if (!dev->hotplugged) { pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTSTA, PCI_EXP_SLTSTA_PDS); + if (pci_dev->cap_present & QEMU_PCIE_LNKSTA_DLLLA) { + pci_word_test_and_set_mask(exp_cap + PCI_EXP_LNKSTA, + PCI_EXP_LNKSTA_DLLLA); + } return; } @@ -355,6 +359,10 @@ void pcie_cap_slot_hotplug_cb(HotplugHandler *hotplug_dev, DeviceState *dev, if (pci_get_function_0(pci_dev)) { pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTSTA, PCI_EXP_SLTSTA_PDS); + if (pci_dev->cap_present & QEMU_PCIE_LNKSTA_DLLLA) { + pci_word_test_and_set_mask(exp_cap + PCI_EXP_LNKSTA, + PCI_EXP_LNKSTA_DLLLA); + } pcie_cap_slot_event(PCI_DEVICE(hotplug_dev), PCI_EXP_HP_EV_PDC | PCI_EXP_HP_EV_ABP); } @@ -531,6 +539,10 @@ void pcie_cap_slot_write_config(PCIDevice *dev, pci_word_test_and_clear_mask(exp_cap + PCI_EXP_SLTSTA, PCI_EXP_SLTSTA_PDS); + if (dev->cap_present & QEMU_PCIE_LNKSTA_DLLLA) { + pci_word_test_and_clear_mask(exp_cap + PCI_EXP_LNKSTA, + PCI_EXP_LNKSTA_DLLLA); + } pci_word_test_and_set_mask(exp_cap + PCI_EXP_SLTSTA, PCI_EXP_SLTSTA_PDC); }