kernel/linux.git/drivers/pci/controller/vmd.c, branch v6.12.80

PCI: vmd: Disable MSI remapping bypass under Xen

2025-05-29T09:02:09+00:00

[ Upstream commit 6c4d5aadf5df31ea0ac025980670eee9beaf466b ] MSI remapping bypass (directly configuring MSI entries for devices on the VMD bus) won't work under Xen, as Xen is not aware of devices in such bus, and hence cannot configure the entries using the pIRQ interface in the PV case, and in the PVH case traps won't be setup for MSI entries for such devices. Until Xen is aware of devices in the VMD bus prevent the VMD_FEAT_CAN_BYPASS_MSI_REMAP capability from being used when running as any kind of Xen guest. The MSI remapping bypass is an optional feature of VMD bridges, and hence when running under Xen it will be masked and devices will be forced to redirect its interrupts from the VMD bridge. That mode of operation must always be supported by VMD bridges and works when Xen is not aware of devices behind the VMD bridge. Signed-off-by: Roger Pau Monné Acked-by: Bjorn Helgaas Message-ID: <20250219092059.90850-3-roger.pau@citrix.com> Signed-off-by: Juergen Gross Signed-off-by: Sasha Levin

PCI: vmd: Make vmd_dev::cfg_lock a raw_spinlock_t type

2025-04-20T08:15:26+00:00

[ Upstream commit 18056a48669a040bef491e63b25896561ee14d90 ] The access to the PCI config space via pci_ops::read and pci_ops::write is a low-level hardware access. The functions can be accessed with disabled interrupts even on PREEMPT_RT. The pci_lock is a raw_spinlock_t for this purpose. A spinlock_t becomes a sleeping lock on PREEMPT_RT, so it cannot be acquired with disabled interrupts. The vmd_dev::cfg_lock is accessed in the same context as the pci_lock. Make vmd_dev::cfg_lock a raw_spinlock_t type so it can be used with interrupts disabled. This was reported as: BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 Call Trace: rt_spin_lock+0x4e/0x130 vmd_pci_read+0x8d/0x100 [vmd] pci_user_read_config_byte+0x6f/0xe0 pci_read_config+0xfe/0x290 sysfs_kf_bin_read+0x68/0x90 Signed-off-by: Ryo Takakura Tested-by: Luis Claudio R. Goncalves Acked-by: Luis Claudio R. Goncalves [bigeasy: reword commit message] Signed-off-by: Sebastian Andrzej Siewior Tested-off-by: Luis Claudio R. Goncalves Link: https://lore.kernel.org/r/20250218080830.ufw3IgyX@linutronix.de [kwilczynski: commit log] Signed-off-by: Krzysztof Wilczyński [bhelgaas: add back report info from https://lore.kernel.org/lkml/20241218115951.83062-1-ryotkkr98@gmail.com/] Signed-off-by: Bjorn Helgaas Signed-off-by: Sasha Levin

PCI: vmd: Set devices to D0 before enabling PM L1 Substates

2024-12-14T19:04:04+00:00

[ Upstream commit d66041063192497a4a97d21dbf86b79a03a7f4fb ] The remapped PCIe Root Port and the child device have PM L1 Substates capability, but they are disabled originally. Here is a failed example on ASUS B1400CEAE: Capabilities: [900 v1] L1 PM Substates L1SubCap: PCI-PM_L1.2+ PCI-PM_L1.1- ASPM_L1.2+ ASPM_L1.1- L1_PM_Substates+ PortCommonModeRestoreTime=32us PortTPowerOnTime=10us L1SubCtl1: PCI-PM_L1.2- PCI-PM_L1.1- ASPM_L1.2+ ASPM_L1.1- T_CommonMode=0us LTR1.2_Threshold=101376ns L1SubCtl2: T_PwrOn=50us Enable PCI-PM L1 PM Substates for devices below VMD while they are in D0 (see PCIe r6.0, sec 5.5.4). Link: https://lore.kernel.org/r/20241001083438.10070-4-jhp@endlessos.org Link: https://bugzilla.kernel.org/show_bug.cgi?id=218394 Signed-off-by: Jian-Hong Pan Signed-off-by: Krzysztof Wilczyński Signed-off-by: Bjorn Helgaas Reviewed-by: Kuppuswamy Sathyanarayanan Signed-off-by: Sasha Levin

PCI: vmd: Add DID 8086:B06F and 8086:B60B for Intel client SKUs

2024-12-14T19:04:04+00:00

[ Upstream commit b727484cace4be22be9321cc0bc9487648ba447b ] Add support for this VMD device which supports the bus restriction mode. The feature that turns off vector 0 for MSI-X remapping is also enabled. Link: https://lore.kernel.org/r/20241011175657.249948-1-nirmal.patel@linux.intel.com Signed-off-by: Nirmal Patel Signed-off-by: Krzysztof Wilczyński Reviewed-by: Manivannan Sadhasivam Signed-off-by: Sasha Levin

Merge branch 'pci/controller/vmd'

2024-09-19T19:25:33+00:00

- Fix whitespace indentation issues (Riyan Dhiman) * pci/controller/vmd: PCI: vmd: Fix indentation issue in vmd_shutdown()

PCI: vmd: Fix indentation issue in vmd_shutdown()

2024-09-01T17:01:20+00:00

The code in vmd_shutdown() had an indentation issue where spaces were used instead of tabs. This commit corrects the indentation to use tabs, adhering to the Linux kernel coding style guidelines. Issue reported by the checkpatch.pl script: ERROR: code indent should use tabs where possible #1056: FILE: drivers/pci/controller/vmd.c:1056: + struct vmd_dev *vmd = pci_get_drvdata(dev);$ WARNING: please, no spaces at the start of a line #1056: FILE: drivers/pci/controller/vmd.c:1056: + struct vmd_dev *vmd = pci_get_drvdata(dev);$ ERROR: code indent should use tabs where possible #1058: FILE: drivers/pci/controller/vmd.c:1058: + vmd_remove_irq_domain(vmd);$ WARNING: please, no spaces at the start of a line #1058: FILE: drivers/pci/controller/vmd.c:1058: + vmd_remove_irq_domain(vmd);$ No functional changes are intended. Link: https://lore.kernel.org/linux-pci/20240901092602.17414-1-riyandhiman14@gmail.com Signed-off-by: Riyan Dhiman [kwilczynski: commit log] Signed-off-by: Krzysztof Wilczyński

PCI: vmd: Silence 'set affinity failed' warning

2024-08-06T17:52:03+00:00

Use MSI_FLAG_NO_AFFINITY, which keeps .irq_set_affinity() unset and allows migrate_one_irq() to exit right away, without warnings like this: IRQ...: set affinity failed(-22) Remove the .irq_set_affinity() implementation that is no longer needed. Link: https://lore.kernel.org/r/20240723132958.41320-13-marek.vasut+renesas@mailbox.org Signed-off-by: Marek Vasut [bhelgaas: commit log] Signed-off-by: Bjorn Helgaas Reviewed-by: Manivannan Sadhasivam Reviewed-by: Nirmal Patel Acked-by: Thomas Gleixner

Merge branch 'pci/misc'

2024-07-19T15:10:33+00:00

- Remove unused struct 'acpi_handle_node' (Dr. David Alan Gilbert) - Use array notation for portdrv .id_table consistently (Masahiro Yamada) - Switch to new Intel CPU model defines (Tony Luck) - Add missing MODULE_DESCRIPTION() macros (Jeff Johnson) * pci/misc: PCI: controller: Add missing MODULE_DESCRIPTION() macros PCI: Add missing MODULE_DESCRIPTION() macros PCI/PM: Switch to new Intel CPU model defines PCI: Use array for .id_table consistently ACPI: PCI: Remove unused struct 'acpi_handle_node'

PCI: vmd: Create domain symlink before pci_bus_add_devices()

2024-07-10T21:55:06+00:00

The vmd driver creates a "domain" symlink in sysfs for each VMD bridge. Previously this symlink was created after pci_bus_add_devices() added devices below the VMD bridge and emitted udev events to announce them to userspace. This led to a race between userspace consumers of the udev events and the kernel creation of the symlink. One such consumer is mdadm, which assembles block devices into a RAID array, and for devices below a VMD bridge, mdadm depends on the "domain" symlink. If mdadm loses the race, it may be unable to assemble a RAID array, which may cause a boot failure or other issues, with complaints like this: (udev-worker)[2149]: nvme1n1: '/sbin/mdadm -I /dev/nvme1n1'(err) 'mdadm: Unable to get real path for '/sys/bus/pci/drivers/vmd/0000:c7:00.5/domain/device'' (udev-worker)[2149]: nvme1n1: '/sbin/mdadm -I /dev/nvme1n1'(err) 'mdadm: /dev/nvme1n1 is not attached to Intel(R) RAID controller.' (udev-worker)[2149]: nvme1n1: '/sbin/mdadm -I /dev/nvme1n1'(err) 'mdadm: No OROM/EFI properties for /dev/nvme1n1' (udev-worker)[2149]: nvme1n1: '/sbin/mdadm -I /dev/nvme1n1'(err) 'mdadm: no RAID superblock on /dev/nvme1n1.' (udev-worker)[2149]: nvme1n1: Process '/sbin/mdadm -I /dev/nvme1n1' failed with exit code 1. This symptom prevents the OS from booting successfully. After a NVMe disk is probed/added by the nvme driver, udevd invokes mdadm to detect if there is a mdraid associated with this NVMe disk, and mdadm determines if a NVMe device is connected to a particular VMD domain by checking the "domain" symlink. For example: Thread A Thread B Thread mdadm vmd_enable_domain pci_bus_add_devices __driver_probe_device ... work_on_cpu schedule_work_on : wakeup Thread B nvme_probe : wakeup scan_work to scan nvme disk and add nvme disk then wakeup udevd : udevd executes mdadm command flush_work main : wait for nvme_probe done ... __driver_probe_device find_driver_devices : probe next nvme device : 1) Detect domain symlink ... 2) Find domain symlink ... from vmd sysfs ... 3) Domain symlink not ... created yet; failed sysfs_create_link : create domain symlink Create the VMD "domain" symlink before invoking pci_bus_add_devices() to avoid this race. Suggested-by: Adrian Huang Link: https://lore.kernel.org/linux-pci/20240605124844.24293-1-sjiwei@163.com Signed-off-by: Jiwei Sun Signed-off-by: Krzysztof Wilczyński [bhelgaas: commit log] Signed-off-by: Bjorn Helgaas Reviewed-by: Nirmal Patel

PCI: controller: Add missing MODULE_DESCRIPTION() macros

2024-07-08T08:36:14+00:00

When ARCH=x86, make allmodconfig && make W=1 C=1 reports: WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/pci/controller/dwc/pci-exynos.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/pci/controller/pci-host-generic.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/pci/controller/pcie-altera.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/pci/controller/pcie-altera-msi.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/pci/controller/pcie-mediatek.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/pci/controller/pcie-mediatek-gen3.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/pci/controller/vmd.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/pci/controller/pcie-apple.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/pci/controller/pcie-mt7621.o Add the missing MODULE_DESCRIPTION() macro. [kwilczynski: update MODULE_DESCRIPTION() text, commit log] Link: https://lore.kernel.org/linux-pci/20240626-md-drivers-pci-controller-v2-1-94c811db7a51@quicinc.com Signed-off-by: Jeff Johnson Signed-off-by: Krzysztof Wilczyński Reviewed-by: AngeloGioacchino Del Regno Acked-by: Nirmal Patel Acked-by: Sergio Paracuellos # MT7621