| Message ID | 20240605124844.24293-1-sjiwei@163.com (mailing list archive) |
|---|---|
| State | New |
| Delegated to: | Krzysztof Wilczyński |
| Headers | show |
| Series | [v3] PCI: vmd: Create domain symlink before pci_bus_add_devices() | expand |
On Wed, 5 Jun 2024 20:48:44 +0800 Jiwei Sun <sjiwei@163.com> wrote: > From: Jiwei Sun <sunjw10@lenovo.com> > > During booting into the kernel, the following error message appears: > > (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, the udevd > executes some rule scripts by invoking mdadm command to detect if > there is a mdraid associated with this NVMe disk. The mdadm > determines if one NVMe devce is connected to a particular VMD domain > by checking the domain symlink. Here is the root cause: > > 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 the > domain ... symlink; 2) > Find the ... domain > symlink from ... vmd > sysfs; 3) The ... domain > symlink is not ... created > yet, failed sysfs_create_link > : create domain symlink > > sysfs_create_link() is invoked at the end of vmd_enable_domain(). > However, this implementation introduces a timing issue, where mdadm > might fail to retrieve the vmd symlink path because the symlink has > not been created yet. > > Fix the issue by creating VMD domain symlinks before invoking > pci_bus_add_devices(). > > Signed-off-by: Jiwei Sun <sunjw10@lenovo.com> > Suggested-by: Adrian Huang <ahuang12@lenovo.com> > --- > v3 changes: > - Per Paul's comment, move sysfs_remove_link() after > pci_stop_root_bus() > > v2 changes: > - Add "()" after function names in subject and commit log > - Move sysfs_create_link() after vmd_attach_resources() > > drivers/pci/controller/vmd.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/drivers/pci/controller/vmd.c > b/drivers/pci/controller/vmd.c index 87b7856f375a..4e7fe2e13cac 100644 > --- a/drivers/pci/controller/vmd.c > +++ b/drivers/pci/controller/vmd.c > @@ -925,6 +925,9 @@ static int vmd_enable_domain(struct vmd_dev *vmd, > unsigned long features) dev_set_msi_domain(&vmd->bus->dev, > dev_get_msi_domain(&vmd->dev->dev)); > > + WARN(sysfs_create_link(&vmd->dev->dev.kobj, > &vmd->bus->dev.kobj, > + "domain"), "Can't create symlink to > domain\n"); + > vmd_acpi_begin(); > > pci_scan_child_bus(vmd->bus); > @@ -964,9 +967,6 @@ static int vmd_enable_domain(struct vmd_dev *vmd, > unsigned long features) pci_bus_add_devices(vmd->bus); > > vmd_acpi_end(); > - > - WARN(sysfs_create_link(&vmd->dev->dev.kobj, > &vmd->bus->dev.kobj, > - "domain"), "Can't create symlink to > domain\n"); return 0; > } > > @@ -1042,8 +1042,8 @@ static void vmd_remove(struct pci_dev *dev) > { > struct vmd_dev *vmd = pci_get_drvdata(dev); > > - sysfs_remove_link(&vmd->dev->dev.kobj, "domain"); > pci_stop_root_bus(vmd->bus); > + sysfs_remove_link(&vmd->dev->dev.kobj, "domain"); > pci_remove_root_bus(vmd->bus); > vmd_cleanup_srcu(vmd); > vmd_detach_resources(vmd); Reviewed-by: Nirmal Patel <nirmal.patel@linux.intel.com> Thanks -nirmal
diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c index 87b7856f375a..4e7fe2e13cac 100644 --- a/drivers/pci/controller/vmd.c +++ b/drivers/pci/controller/vmd.c @@ -925,6 +925,9 @@ static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features) dev_set_msi_domain(&vmd->bus->dev, dev_get_msi_domain(&vmd->dev->dev)); + WARN(sysfs_create_link(&vmd->dev->dev.kobj, &vmd->bus->dev.kobj, + "domain"), "Can't create symlink to domain\n"); + vmd_acpi_begin(); pci_scan_child_bus(vmd->bus); @@ -964,9 +967,6 @@ static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features) pci_bus_add_devices(vmd->bus); vmd_acpi_end(); - - WARN(sysfs_create_link(&vmd->dev->dev.kobj, &vmd->bus->dev.kobj, - "domain"), "Can't create symlink to domain\n"); return 0; } @@ -1042,8 +1042,8 @@ static void vmd_remove(struct pci_dev *dev) { struct vmd_dev *vmd = pci_get_drvdata(dev); - sysfs_remove_link(&vmd->dev->dev.kobj, "domain"); pci_stop_root_bus(vmd->bus); + sysfs_remove_link(&vmd->dev->dev.kobj, "domain"); pci_remove_root_bus(vmd->bus); vmd_cleanup_srcu(vmd); vmd_detach_resources(vmd);