From 1ed1f8fc20a4883bc0bc1f58d299b0278abc5442 Mon Sep 17 00:00:00 2001 From: Matthew Rosato Date: Fri, 9 Dec 2022 14:57:00 -0500 Subject: [PATCH 8/9] s390x/pci: reset ISM passthrough devices on shutdown and system reset MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RH-Author: Cédric Le Goater RH-MergeRequest: 141: s390x/pci: reset ISM passthrough devices on shutdown and system reset RH-Bugzilla: 2163701 RH-Acked-by: Thomas Huth RH-Acked-by: Cornelia Huck RH-Acked-by: Miroslav Rezanina RH-Commit: [3/3] c531352b9d57f51ba938d4c46ee19a5706ade697 (clegoate/qemu-kvm-c9s) ISM device firmware stores unique state information that can can cause a wholesale unmap of the associated IOMMU (e.g. when we get a termination signal for QEMU) to trigger firmware errors because firmware believes we are attempting to invalidate entries that are still in-use by the guest OS (when in fact that guest is in the process of being terminated or rebooted). To alleviate this, register both a shutdown notifier (for unexpected termination cases e.g. virsh destroy) as well as a reset callback (for cases like guest OS reboot). For each of these scenarios, trigger PCI device reset; this is enough to indicate to firmware that the IOMMU is no longer in-use by the guest OS, making it safe to invalidate any associated IOMMU entries. Fixes: 15d0e7942d3b ("s390x/pci: don't fence interpreted devices without MSI-X") Signed-off-by: Matthew Rosato Message-Id: <20221209195700.263824-1-mjrosato@linux.ibm.com> Reviewed-by: Eric Farman [thuth: Adjusted the hunk in s390-pci-vfio.c due to different context] Signed-off-by: Thomas Huth (cherry picked from commit 03451953c79e6b31f7860ee0c35b28e181d573c1) Signed-off-by: Cédric Le Goater --- hw/s390x/s390-pci-bus.c | 28 ++++++++++++++++++++++++++++ hw/s390x/s390-pci-vfio.c | 2 ++ include/hw/s390x/s390-pci-bus.h | 5 +++++ 3 files changed, 35 insertions(+) diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c index 977e7daa15..02751f3597 100644 --- a/hw/s390x/s390-pci-bus.c +++ b/hw/s390x/s390-pci-bus.c @@ -24,6 +24,8 @@ #include "hw/pci/msi.h" #include "qemu/error-report.h" #include "qemu/module.h" +#include "sysemu/reset.h" +#include "sysemu/runstate.h" #ifndef DEBUG_S390PCI_BUS #define DEBUG_S390PCI_BUS 0 @@ -150,10 +152,30 @@ out: psccb->header.response_code = cpu_to_be16(rc); } +static void s390_pci_shutdown_notifier(Notifier *n, void *opaque) +{ + S390PCIBusDevice *pbdev = container_of(n, S390PCIBusDevice, + shutdown_notifier); + + pci_device_reset(pbdev->pdev); +} + +static void s390_pci_reset_cb(void *opaque) +{ + S390PCIBusDevice *pbdev = opaque; + + pci_device_reset(pbdev->pdev); +} + static void s390_pci_perform_unplug(S390PCIBusDevice *pbdev) { HotplugHandler *hotplug_ctrl; + if (pbdev->pft == ZPCI_PFT_ISM) { + notifier_remove(&pbdev->shutdown_notifier); + qemu_unregister_reset(s390_pci_reset_cb, pbdev); + } + /* Unplug the PCI device */ if (pbdev->pdev) { DeviceState *pdev = DEVICE(pbdev->pdev); @@ -1111,6 +1133,12 @@ static void s390_pcihost_plug(HotplugHandler *hotplug_dev, DeviceState *dev, pbdev->fh |= FH_SHM_VFIO; pbdev->forwarding_assist = false; } + /* Register shutdown notifier and reset callback for ISM devices */ + if (pbdev->pft == ZPCI_PFT_ISM) { + pbdev->shutdown_notifier.notify = s390_pci_shutdown_notifier; + qemu_register_shutdown_notifier(&pbdev->shutdown_notifier); + qemu_register_reset(s390_pci_reset_cb, pbdev); + } } else { pbdev->fh |= FH_SHM_EMUL; /* Always intercept emulated devices */ diff --git a/hw/s390x/s390-pci-vfio.c b/hw/s390x/s390-pci-vfio.c index f7bf36cec8..f51190d466 100644 --- a/hw/s390x/s390-pci-vfio.c +++ b/hw/s390x/s390-pci-vfio.c @@ -124,6 +124,8 @@ static void s390_pci_read_base(S390PCIBusDevice *pbdev, /* The following values remain 0 until we support other FMB formats */ pbdev->zpci_fn.fmbl = 0; pbdev->zpci_fn.pft = 0; + /* Store function type separately for type-specific behavior */ + pbdev->pft = cap->pft; /* * If appropriate, reduce the size of the supported DMA aperture reported diff --git a/include/hw/s390x/s390-pci-bus.h b/include/hw/s390x/s390-pci-bus.h index 1c46e3a269..e0a9f9385b 100644 --- a/include/hw/s390x/s390-pci-bus.h +++ b/include/hw/s390x/s390-pci-bus.h @@ -39,6 +39,9 @@ #define UID_CHECKING_ENABLED 0x01 #define ZPCI_DTSM 0x40 +/* zPCI Function Types */ +#define ZPCI_PFT_ISM 5 + OBJECT_DECLARE_SIMPLE_TYPE(S390pciState, S390_PCI_HOST_BRIDGE) OBJECT_DECLARE_SIMPLE_TYPE(S390PCIBus, S390_PCI_BUS) OBJECT_DECLARE_SIMPLE_TYPE(S390PCIBusDevice, S390_PCI_DEVICE) @@ -344,6 +347,7 @@ struct S390PCIBusDevice { uint16_t noi; uint16_t maxstbl; uint8_t sum; + uint8_t pft; S390PCIGroup *pci_group; ClpRspQueryPci zpci_fn; S390MsixInfo msix; @@ -352,6 +356,7 @@ struct S390PCIBusDevice { MemoryRegion msix_notify_mr; IndAddr *summary_ind; IndAddr *indicator; + Notifier shutdown_notifier; bool pci_unplug_request_processed; bool unplug_requested; bool interp; -- 2.31.1