Csdrhrt

Recently, I want to change all my block devices' default scheduler. I found udev rules is a great choice. However, why can't I get all available attributes through udevadm info -a /dev/sda command? e.g. ATTR{queue/scheduler} is not listed by this command.

Output of the command:

    looking at device '/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host1/target1:0:0/1:0:0:0/block/sda':

    KERNEL=="sda"

    SUBSYSTEM=="block"

    DRIVER==""

    ATTR{SUBSYSTEM}=="block"

    ATTR{DEVTYPE}=="disk"

    ATTR{MAJOR}=="8"

    ATTR{MINOR}=="0"

    ATTR{USEC_INITIALIZED}=="79339899"

    ATTR{ID_VENDOR}=="WD"

    ATTR{ID_VENDOR_ENC}=="WDx20x20x20x20x20x20"

    ATTR{ID_VENDOR_ID}=="1058"

    ATTR{ID_MODEL}=="My_Passport_25E2"

    ATTR{ID_MODEL_ENC}=="Myx20Passportx2025E2"

    ATTR{ID_MODEL_ID}=="25e2"

    ATTR{ID_REVISION}=="4005"

    ATTR{ID_SERIAL}=="WD_My_Passport_25E2_57584831413138394C335632-0:0"

    ATTR{ID_SERIAL_SHORT}=="57584831413138394C335632"

    ATTR{ID_TYPE}=="disk"

    ATTR{ID_INSTANCE}=="0:0"

    ATTR{ID_BUS}=="usb"

    ATTR{ID_USB_INTERFACES}==":080650:"

    ATTR{ID_USB_INTERFACE_NUM}=="00"

    ATTR{ID_USB_DRIVER}=="usb-storage"

    ATTR{ID_PATH}=="pci-0000:00:14.0-usb-0:1:1.0-scsi-0:0:0:0"

    ATTR{ID_PATH_TAG}=="pci-0000_00_14_0-usb-0_1_1_0-scsi-0_0_0_0"

    ATTR{ID_PART_TABLE_UUID}=="f709913a-6a76-420d-8df7-f19a720675cb"

    ATTR{ID_PART_TABLE_TYPE}=="gpt"

    ATTR{TAGS}==":systemd:"



  looking at parent device '/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host1/target1:0:0/1:0:0:0':

    KERNELS=="1:0:0:0"

    SUBSYSTEMS=="scsi"

    DRIVERS=="sd"

    ATTRS{SUBSYSTEM}=="scsi"

    ATTRS{DRIVER}=="sd"

    ATTRS{DEVTYPE}=="scsi_device"

    ATTRS{MODALIAS}=="scsi:t-0x00"



  looking at parent device '/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host1/target1:0:0':

    KERNELS=="target1:0:0"

    SUBSYSTEMS=="scsi"

    DRIVERS==""

    ATTRS{SUBSYSTEM}=="scsi"

    ATTRS{DEVTYPE}=="scsi_target"



  looking at parent device '/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/host1':

    KERNELS=="host1"

    SUBSYSTEMS=="scsi"

    DRIVERS==""

    ATTRS{SUBSYSTEM}=="scsi"

    ATTRS{DEVTYPE}=="scsi_host"



  looking at parent device '/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0':

    KERNELS=="2-1:1.0"

    SUBSYSTEMS=="usb"

    DRIVERS=="usb-storage"

    ATTRS{SUBSYSTEM}=="usb"

    ATTRS{DRIVER}=="usb-storage"

    ATTRS{DEVTYPE}=="usb_interface"

    ATTRS{PRODUCT}=="1058/25e2/4005"

    ATTRS{TYPE}=="0/0/0"

    ATTRS{INTERFACE}=="8/6/80"

    ATTRS{MODALIAS}=="usb:v1058p25E2d4005dc00dsc00dp00ic08isc06ip50in00"

    ATTRS{USEC_INITIALIZED}=="72626419"

    ATTRS{ID_VENDOR_FROM_DATABASE}=="Western Digital Technologies, Inc."

    ATTRS{ID_MODEL_FROM_DATABASE}=="My Passport (WD40NMZW)"



  looking at parent device '/devices/pci0000:00/0000:00:14.0/usb2/2-1':

    KERNELS=="2-1"

    SUBSYSTEMS=="usb"

    DRIVERS=="usb"

    ATTRS{SUBSYSTEM}=="usb"

    ATTRS{DRIVER}=="usb"

    ATTRS{DEVTYPE}=="usb_device"

    ATTRS{PRODUCT}=="1058/25e2/4005"

    ATTRS{TYPE}=="0/0/0"

    ATTRS{BUSNUM}=="002"

    ATTRS{DEVNUM}=="002"

    ATTRS{MAJOR}=="189"

    ATTRS{MINOR}=="129"

    ATTRS{USEC_INITIALIZED}=="72625379"

    ATTRS{ID_VENDOR}=="Western_Digital"

    ATTRS{ID_VENDOR_ENC}=="Westernx20Digital"

    ATTRS{ID_VENDOR_ID}=="1058"

    ATTRS{ID_MODEL}=="My_Passport_25E2"

    ATTRS{ID_MODEL_ENC}=="Myx20Passportx2025E2"

    ATTRS{ID_MODEL_ID}=="25e2"

    ATTRS{ID_REVISION}=="4005"

    ATTRS{ID_SERIAL}=="Western_Digital_My_Passport_25E2_57584831413138394C335632"

    ATTRS{ID_SERIAL_SHORT}=="57584831413138394C335632"

    ATTRS{ID_BUS}=="usb"

    ATTRS{ID_USB_INTERFACES}==":080650:"

    ATTRS{ID_VENDOR_FROM_DATABASE}=="Western Digital Technologies, Inc."

    ATTRS{ID_MODEL_FROM_DATABASE}=="My Passport (WD40NMZW)"



  looking at parent device '/devices/pci0000:00/0000:00:14.0/usb2':

    KERNELS=="usb2"

    SUBSYSTEMS=="usb"

    DRIVERS=="usb"

    ATTRS{SUBSYSTEM}=="usb"

    ATTRS{DRIVER}=="usb"

    ATTRS{DEVTYPE}=="usb_device"

    ATTRS{PRODUCT}=="1d6b/3/420"

    ATTRS{TYPE}=="9/0/3"

    ATTRS{BUSNUM}=="002"

    ATTRS{DEVNUM}=="001"

    ATTRS{MAJOR}=="189"

    ATTRS{MINOR}=="128"

    ATTRS{USEC_INITIALIZED}=="1862070"

    ATTRS{ID_VENDOR}=="Linux_4.20.5-1-ck-skylake_xhci-hcd"

    ATTRS{ID_VENDOR_ENC}=="Linuxx204.20.5-1-ck-skylakex20xhci-hcd"

    ATTRS{ID_VENDOR_ID}=="1d6b"

    ATTRS{ID_MODEL}=="xHCI_Host_Controller"

    ATTRS{ID_MODEL_ENC}=="xHCIx20Hostx20Controller"

    ATTRS{ID_MODEL_ID}=="0003"

    ATTRS{ID_REVISION}=="0420"

    ATTRS{ID_SERIAL}=="Linux_4.20.5-1-ck-skylake_xhci-hcd_xHCI_Host_Controller_0000:00:14.0"

    ATTRS{ID_SERIAL_SHORT}=="0000:00:14.0"

    ATTRS{ID_BUS}=="usb"

    ATTRS{ID_USB_INTERFACES}==":090000:"

    ATTRS{ID_VENDOR_FROM_DATABASE}=="Linux Foundation"

    ATTRS{ID_MODEL_FROM_DATABASE}=="3.0 root hub"

    ATTRS{ID_PATH}=="pci-0000:00:14.0"

    ATTRS{ID_PATH_TAG}=="pci-0000_00_14_0"

    ATTRS{ID_FOR_SEAT}=="usb-pci-0000_00_14_0"

    ATTRS{TAGS}==":seat:"



  looking at parent device '/devices/pci0000:00/0000:00:14.0':

    KERNELS=="0000:00:14.0"

    SUBSYSTEMS=="pci"

    DRIVERS=="xhci_hcd"

    ATTRS{SUBSYSTEM}=="pci"

    ATTRS{DRIVER}=="xhci_hcd"

    ATTRS{PCI_CLASS}=="C0330"

    ATTRS{PCI_ID}=="8086:9DED"

    ATTRS{PCI_SUBSYS_ID}=="1028:08A5"

    ATTRS{PCI_SLOT_NAME}=="0000:00:14.0"

    ATTRS{MODALIAS}=="pci:v00008086d00009DEDsv00001028sd000008A5bc0Csc03i30"

    ATTRS{USEC_INITIALIZED}=="1855424"

    ATTRS{ID_PCI_CLASS_FROM_DATABASE}=="Serial bus controller"

    ATTRS{ID_PCI_SUBCLASS_FROM_DATABASE}=="USB controller"

    ATTRS{ID_PCI_INTERFACE_FROM_DATABASE}=="XHCI"

    ATTRS{ID_VENDOR_FROM_DATABASE}=="Intel Corporation"



  looking at parent device '/devices/pci0000:00':

    KERNELS=="pci0000:00"

    SUBSYSTEMS==""

    DRIVERS==""