From 2841ab435bca9f102311e01bf157d5fa878935dc Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Fri, 21 Jun 2019 00:12:22 -0400 Subject: [PATCH] pcie: check that slt ctrl changed before deleting During boot, linux would sometimes overwrites control of a powered off slot before powering it on. Unfortunately QEMU interprets that as a power off request and ejects the device. For example: /x86_64-softmmu/qemu-system-x86_64 -enable-kvm -S -machine q35 \ -device pcie-root-port,id=pcie_root_port_0,slot=2,chassis=2,addr=0x2,bus=pcie.0 \ -monitor stdio disk.qcow2 (qemu)device_add virtio-balloon-pci,id=balloon,bus=pcie_root_port_0 (qemu)cont Balloon is deleted during guest boot. To fix, save control beforehand and check that power or led state actually change before ejecting. Note: this is more a hack than a solution, ideally we'd find a better way to detect ejects, or move away from ejects completely and instead monitor whether it's safe to delete device due to e.g. its power state. Signed-off-by: Michael S. Tsirkin Reviewed-by: Marcel Apfelbaum Reviewed-by: Igor Mammedov Tested-by: Igor Mammedov --- hw/pci-bridge/pcie_root_port.c | 5 ++++- hw/pci-bridge/xio3130_downstream.c | 5 ++++- hw/pci/pcie.c | 14 ++++++++++++-- include/hw/pci/pcie.h | 3 ++- 4 files changed, 22 insertions(+), 5 deletions(-) diff --git a/hw/pci-bridge/pcie_root_port.c b/hw/pci-bridge/pcie_root_port.c index 92f253c924..09019ca05d 100644 --- a/hw/pci-bridge/pcie_root_port.c +++ b/hw/pci-bridge/pcie_root_port.c @@ -31,10 +31,13 @@ static void rp_write_config(PCIDevice *d, uint32_t address, { uint32_t root_cmd = pci_get_long(d->config + d->exp.aer_cap + PCI_ERR_ROOT_COMMAND); + uint16_t slt_ctl, slt_sta; + + pcie_cap_slot_get(d, &slt_ctl, &slt_sta); pci_bridge_write_config(d, address, val, len); rp_aer_vector_update(d); - pcie_cap_slot_write_config(d, address, val, len); + pcie_cap_slot_write_config(d, slt_ctl, slt_sta, address, val, len); pcie_aer_write_config(d, address, val, len); pcie_aer_root_write_config(d, address, val, len, root_cmd); } diff --git a/hw/pci-bridge/xio3130_downstream.c b/hw/pci-bridge/xio3130_downstream.c index 264e37d6a6..899b0fd6c9 100644 --- a/hw/pci-bridge/xio3130_downstream.c +++ b/hw/pci-bridge/xio3130_downstream.c @@ -41,9 +41,12 @@ static void xio3130_downstream_write_config(PCIDevice *d, uint32_t address, uint32_t val, int len) { + uint16_t slt_ctl, slt_sta; + + pcie_cap_slot_get(d, &slt_sta, &slt_ctl); pci_bridge_write_config(d, address, val, len); pcie_cap_flr_write_config(d, address, val, len); - pcie_cap_slot_write_config(d, address, val, len); + pcie_cap_slot_write_config(d, slt_ctl, slt_sta, address, val, len); pcie_aer_write_config(d, address, val, len); } diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c index b22527000d..f8490a00de 100644 --- a/hw/pci/pcie.c +++ b/hw/pci/pcie.c @@ -594,7 +594,15 @@ void pcie_cap_slot_reset(PCIDevice *dev) hotplug_event_update_event_status(dev); } -void pcie_cap_slot_write_config(PCIDevice *dev, +void pcie_cap_slot_get(PCIDevice *dev, uint16_t *slt_ctl, uint16_t *slt_sta) +{ + uint32_t pos = dev->exp.exp_cap; + uint8_t *exp_cap = dev->config + pos; + *slt_ctl = pci_get_word(exp_cap + PCI_EXP_SLTCTL); + *slt_sta = pci_get_word(exp_cap + PCI_EXP_SLTSTA); +} + +void pcie_cap_slot_write_config(PCIDevice *dev, uint16_t slt_ctl, uint16_t slt_sta, uint32_t addr, uint32_t val, int len) { uint32_t pos = dev->exp.exp_cap; @@ -623,7 +631,9 @@ void pcie_cap_slot_write_config(PCIDevice *dev, * controller is off, it is safe to detach the devices. */ if ((sltsta & PCI_EXP_SLTSTA_PDS) && (val & PCI_EXP_SLTCTL_PCC) && - ((val & PCI_EXP_SLTCTL_PIC_OFF) == PCI_EXP_SLTCTL_PIC_OFF)) { + (val & PCI_EXP_SLTCTL_PIC_OFF) == PCI_EXP_SLTCTL_PIC_OFF && + (!(slt_ctl & PCI_EXP_SLTCTL_PCC) || + (slt_ctl & PCI_EXP_SLTCTL_PIC_OFF) != PCI_EXP_SLTCTL_PIC_OFF)) { PCIBus *sec_bus = pci_bridge_get_sec_bus(PCI_BRIDGE(dev)); pci_for_each_device(sec_bus, pci_bus_num(sec_bus), pcie_unplug_device, NULL); diff --git a/include/hw/pci/pcie.h b/include/hw/pci/pcie.h index e30334d74d..8d90c0e193 100644 --- a/include/hw/pci/pcie.h +++ b/include/hw/pci/pcie.h @@ -107,7 +107,8 @@ void pcie_cap_lnkctl_reset(PCIDevice *dev); void pcie_cap_slot_init(PCIDevice *dev, uint16_t slot); void pcie_cap_slot_reset(PCIDevice *dev); -void pcie_cap_slot_write_config(PCIDevice *dev, +void pcie_cap_slot_get(PCIDevice *dev, uint16_t *slot_ctl, uint16_t *slt_sta); +void pcie_cap_slot_write_config(PCIDevice *dev, uint16_t slot_ctl, uint16_t slt_sta, uint32_t addr, uint32_t val, int len); int pcie_cap_slot_post_load(void *opaque, int version_id); void pcie_cap_slot_push_attention_button(PCIDevice *dev); -- 2.11.4.GIT