crash —— 如何查看PCI设备拓扑？

crash> dev -p
    ROOT BUS     BUSNAME
ffff893eaeb43000 0000:00
      PCI DEV      DO:BU:SL.FN  CLASS   PCI_ID      TYPE
  ffff88deaf813000 0000:00:00.0  0600  8086:2020 ROOT_PORT
  ffff88deaf812000 0000:00:04.0  0880  8086:2021   RC_END
  ffff88deaf817000 0000:00:04.1  0880  8086:2021   RC_END
  ffff88deaf810000 0000:00:04.2  0880  8086:2021   RC_END
  ffff88deaf811000 0000:00:04.3  0880  8086:2021   RC_END
  ffff88deaf814000 0000:00:04.4  0880  8086:2021   RC_END
  ffff88deaf816000 0000:00:04.5  0880  8086:2021   RC_END
  ffff88deaf815000 0000:00:04.6  0880  8086:2021   RC_END
  ffff893eaeb58000 0000:00:04.7  0880  8086:2021   RC_END
  ffff893eaeb59000 0000:00:05.0  0880  8086:2024   RC_END
  ffff893eaeb5c000 0000:00:05.2  0880  8086:2025   RC_END
  ffff893eaeb5e000 0000:00:05.4  0800  8086:2026   RC_END
  ffff893eaeb5d000 0000:00:08.0  0880  8086:2014   RC_END
  ffff893eaeb5b000 0000:00:08.1  1101  8086:2015  ENDPOINT
  ffff893eaeb5a000 0000:00:08.2  0880  8086:2016   RC_END
  ffff893eaeb5f000 0000:00:11.0  ff00  8086:a1ec  ENDPOINT
  ffff893eaeb6d000 0000:00:11.1  ff00  8086:a1ed  ENDPOINT
  ffff893eaeb6b000 0000:00:11.5  0106  8086:a1d2  ENDPOINT
  ffff893eaeb6a000 0000:00:14.0  0c03  8086:a1af  ENDPOINT
  ffff893eaeb6f000 0000:00:14.2  1180  8086:a1b1  ENDPOINT
  ffff893eaeb68000 0000:00:16.0  0780  8086:a1ba  ENDPOINT
  ffff893eaeb69000 0000:00:16.1  0780  8086:a1bb  ENDPOINT
  ffff893eaeb6c000 0000:00:16.4  0780  8086:a1be  ENDPOINT
  ffff893eaeb6e000 0000:00:17.0  0106  8086:a182  ENDPOINT
  ffff893eaeb83000 0000:00:1c.0  0604  8086:a190 ROOT_PORT [BRIDGE]
  ffff893eaeb82000 0000:00:1c.4  0604  8086:a194 ROOT_PORT [BRIDGE]
  ffff893eaeb87000 0000:00:1c.5  0604  8086:a195 ROOT_PORT [BRIDGE]
  ffff893eaeb80000 0000:00:1f.0  0601  8086:a1c2  ENDPOINT
  ffff893eaeb81000 0000:00:1f.2  0580  8086:a1a1  ENDPOINT
  ffff893eaeb84000 0000:00:1f.4  0c05  8086:a1a3  ENDPOINT
  ffff893eaeb86000 0000:00:1f.5  0c80  8086:a1a4  ENDPOINT
      PCI BUS         PARENT BUS
  ffff893eaeb47800 ffff893eaeb43000
      PCI DEV      DO:BU:SL.FN  CLASS   PCI_ID      TYPE
  ffff893eaeb83000 0000:00:1c.0  0604  8086:a190 ROOT_PORT [BRIDGE]
      PCI BUS         PARENT BUS
  ffff893eaeb46800 ffff893eaeb43000
      PCI DEV      DO:BU:SL.FN  CLASS   PCI_ID      TYPE
  ffff893eaeb82000 0000:00:1c.4  0604  8086:a194 ROOT_PORT [BRIDGE]
  ffff893eaeb85000 0000:02:00.0  0300  19e5:1711  LEG_END
      PCI BUS         PARENT BUS
  ffff893eaeb44800 ffff893eaeb43000
      PCI DEV      DO:BU:SL.FN  CLASS   PCI_ID      TYPE
  ffff893eaeb87000 0000:00:1c.5  0604  8086:a195 ROOT_PORT [BRIDGE]
  ffff893eaeb9d000 0000:03:00.0  1180  19e5:1710  ENDPOINT
...