kernel/drivers/pci/controller/pci-hyperv.c, branch linux-rolling-stable

PCI: Enable host bridge emulation for PCI_DOMAINS_GENERIC platforms

2025-10-28T17:36:34Z

The ability to emulate a host bridge is useful not only for hardware PCI controllers like CONFIG_VMD, or virtual PCI controllers like CONFIG_PCI_HYPERV, but also for test and development scenarios like CONFIG_SAMPLES_DEVSEC [1]. One stumbling block for defining CONFIG_SAMPLES_DEVSEC, a sample implementation of a platform TSM for PCI Device Security, is the need to accommodate PCI_DOMAINS_GENERIC architectures alongside x86 [2]. In support of supplementing the existing CONFIG_PCI_BRIDGE_EMUL infrastructure for host bridges: * Introduce pci_bus_find_emul_domain_nr() as a common way to find a free PCI domain number whether that is to reuse the existing dynamic allocation code in the !ACPI case, or to assign an unused domain above the last ACPI segment. * Convert pci-hyperv to the new allocator so that the PCI core can unconditionally assume that bridge->domain_nr != PCI_DOMAIN_NR_NOT_SET is the dynamically allocated case. A follow on patch can also convert vmd to the new scheme. Currently vmd is limited to CONFIG_PCI_DOMAINS_GENERIC=n (x86) so, unlike pci-hyperv, it does not immediately conflict with this new pci_bus_find_emul_domain_nr() mechanism. Link: http://lore.kernel.org/174107249038.1288555.12362100502109498455.stgit@dwillia2-xfh.jf.intel.com [1] Reported-by: Suzuki K Poulose Closes: http://lore.kernel.org/20250311144601.145736-3-suzuki.poulose@arm.com [2] Signed-off-by: Dan Williams Signed-off-by: Bjorn Helgaas Tested-by: Suzuki K Poulose Tested-by: Michael Kelley Reviewed-by: Michael Kelley Cc: Lorenzo Pieralisi Cc: Manivannan Sadhasivam Cc: Rob Herring Cc: K. Y. Srinivasan Cc: Haiyang Zhang Cc: Wei Liu Cc: Dexuan Cui Link: https://patch.msgid.link/20251024224622.1470555-2-dan.j.williams@intel.com

PCI: hv: Remove unused parameter of hv_msi_free()

2025-09-08T04:58:40Z

The 'info' parameter of hv_msi_free() is unused. Delete it. Signed-off-by: Nam Cao Signed-off-by: Manivannan Sadhasivam Acked-by: Wei Liu

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2025-07-24T18:10:46Z

Cross-merge networking fixes after downstream PR (net-6.16-rc8). Conflicts: drivers/net/ethernet/microsoft/mana/gdma_main.c 9669ddda18fb ("net: mana: Fix warnings for missing export.h header inclusion") 755391121038 ("net: mana: Allocate MSI-X vectors dynamically") https://lore.kernel.org/20250711130752.23023d98@canb.auug.org.au Adjacent changes: drivers/net/ethernet/ti/icssg/icssg_prueth.h 6e86fb73de0f ("net: ti: icssg-prueth: Fix buffer allocation for ICSSG") ffe8a4909176 ("net: ti: icssg-prueth: Read firmware-names from device tree") Signed-off-by: Jakub Kicinski

PCI: hv: Use the correct hypercall for unmasking interrupts on nested

2025-07-15T06:24:16Z

Running as nested root on MSHV imposes a different requirement for the pci-hyperv controller. In this setup, the interrupt will first come to the L1 (nested) hypervisor, which will deliver it to the appropriate root CPU. Instead of issuing the RETARGET hypercall, issue the MAP_DEVICE_INTERRUPT hypercall to L1 to complete the setup. Rename hv_arch_irq_unmask() to hv_irq_retarget_interrupt(). Co-developed-by: Jinank Jain Signed-off-by: Jinank Jain Signed-off-by: Stanislav Kinsburskii Signed-off-by: Nuno Das Neves Reviewed-by: Roman Kisel Reviewed-by: Michael Kelley Acked-by: Bjorn Helgaas Link: https://lore.kernel.org/r/1752261532-7225-4-git-send-email-nunodasneves@linux.microsoft.com Signed-off-by: Wei Liu Message-ID: <1752261532-7225-4-git-send-email-nunodasneves@linux.microsoft.com>

PCI: hv: Switch to msi_create_parent_irq_domain()

2025-07-11T11:57:00Z

Move away from the legacy MSI domain setup, switch to use msi_create_parent_irq_domain(). While doing the conversion, I noticed that hv_compose_msi_msg() is doing more than it is supposed to (composing message). This function also allocates and populates struct tran_int_desc, which should be done in hv_pcie_domain_alloc() instead. It works, but it is not the correct design. However, I have no hardware to test such change, therefore I leave a TODO note. Acked-by: Bjorn Helgaas Reviewed-by: Thomas Gleixner Signed-off-by: Nam Cao Reviewed-by: Michael Kelley Tested-by: Michael Kelley Signed-off-by: David S. Miller

PCI: hv: Don't load the driver for baremetal root partition

2025-07-09T23:47:07Z

The root partition only uses VMBus when running nested. When running on baremetal the Hyper-V PCI driver is not needed, so do not initialize it. Signed-off-by: Mukesh Rathor Signed-off-by: Nuno Das Neves Reviewed-by: Roman Kisel Reviewed-by: Michael Kelley Acked-by: Bjorn Helgaas Link: https://lore.kernel.org/r/1751582677-30930-2-git-send-email-nunodasneves@linux.microsoft.com Signed-off-by: Wei Liu Message-ID: <1751582677-30930-2-git-send-email-nunodasneves@linux.microsoft.com>

PCI: hv: Allow dynamic MSI-X vector allocation

2025-06-17T06:15:14Z

Allow dynamic MSI-X vector allocation for pci_hyperv PCI controller by adding support for the flag MSI_FLAG_PCI_MSIX_ALLOC_DYN and using pci_msix_prepare_desc() to prepare the MSI-X descriptors. Feature support added for both x86 and ARM64 Signed-off-by: Shradha Gupta Reviewed-by: Haiyang Zhang Reviewed-by: Saurabh Sengar Acked-by: Bjorn Helgaas

Merge tag 'hyperv-next-signed-20250602' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

2025-06-03T15:39:20Z

Pull hyperv updates from Wei Liu: - Support for Virtual Trust Level (VTL) on arm64 (Roman Kisel) - Fixes for Hyper-V UIO driver (Long Li) - Fixes for Hyper-V PCI driver (Michael Kelley) - Select CONFIG_SYSFB for Hyper-V guests (Michael Kelley) - Documentation updates for Hyper-V VMBus (Michael Kelley) - Enhance logging for hv_kvp_daemon (Shradha Gupta) * tag 'hyperv-next-signed-20250602' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: (23 commits) Drivers: hv: Always select CONFIG_SYSFB for Hyper-V guests Drivers: hv: vmbus: Add comments about races with "channels" sysfs dir Documentation: hyperv: Update VMBus doc with new features and info PCI: hv: Remove unnecessary flex array in struct pci_packet Drivers: hv: Remove hv_alloc/free_* helpers Drivers: hv: Use kzalloc for panic page allocation uio_hv_generic: Align ring size to system page uio_hv_generic: Use correct size for interrupt and monitor pages Drivers: hv: Allocate interrupt and monitor pages aligned to system page boundary arch/x86: Provide the CPU number in the wakeup AP callback x86/hyperv: Fix APIC ID and VP index confusion in hv_snp_boot_ap() PCI: hv: Get vPCI MSI IRQ domain from DeviceTree ACPI: irq: Introduce acpi_get_gsi_dispatcher() Drivers: hv: vmbus: Introduce hv_get_vmbus_root_device() Drivers: hv: vmbus: Get the IRQ number from DeviceTree dt-bindings: microsoft,vmbus: Add interrupt and DMA coherence properties arm64, x86: hyperv: Report the VTL the system boots in arm64: hyperv: Initialize the Virtual Trust Level field Drivers: hv: Provide arch-neutral implementation of get_vtl() Drivers: hv: Enable VTL mode for arm64 ...

PCI: hv: Remove unnecessary flex array in struct pci_packet

2025-05-23T16:30:56Z

struct pci_packet contains a "message" field that is a flex array of struct pci_message. struct pci_packet is usually followed by a second struct in a containing struct that is defined locally in individual functions in pci-hyperv.c. As such, the compiler flag -Wflex-array-member-not-at-end (introduced in gcc-14) generates multiple warnings such as: drivers/pci/controller/pci-hyperv.c:3809:35: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] The Linux kernel intends to introduce this compiler flag in standard builds, so the current code is problematic in generating these warnings. The "message" field is used only to locate the start of the second struct, and not as an array. Because the second struct can be addressed directly, the "message" field is not really necessary. Rather than try to fix its usage to meet the requirements of -Wflex-array-member-not-at-end, just eliminate the field and either directly reference the second struct, or use "pkt + 1" when "pkt" is dynamically allocated. Reported-by: Gustavo A. R. Silva Signed-off-by: Michael Kelley Link: https://lore.kernel.org/r/20250514044440.48924-1-mhklinux@outlook.com Signed-off-by: Wei Liu Message-ID: <20250514044440.48924-1-mhklinux@outlook.com>

PCI: hv: Get vPCI MSI IRQ domain from DeviceTree

2025-05-23T16:30:55Z

The hyperv-pci driver uses ACPI for MSI IRQ domain configuration on arm64. It won't be able to do that in the VTL mode where only DeviceTree can be used. Update the hyperv-pci driver to get vPCI MSI IRQ domain in the DeviceTree case, too. Signed-off-by: Roman Kisel Acked-by: Bjorn Helgaas Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/20250428210742.435282-12-romank@linux.microsoft.com Signed-off-by: Wei Liu Message-ID: <20250428210742.435282-12-romank@linux.microsoft.com>