Questão de Linux Administration #019e3987

The lspci command is a utility for displaying information about PCI buses and devices connected to them. It reads the PCI configuration space and presents details about each device.

How it Works

lspci queries the kernel's PCI subsystem, which maintains a database of all detected PCI devices. By default, it shows device class, vendor, device ID, and subsystem information. With options like -v (verbose) or -vv, it can display additional details such as IRQ settings, memory addresses, and bus speed.

Correct Choices

• Device IRQ settings: lspci -v shows the IRQ number assigned to each PCI device. This is part of the PCI configuration space and is correctly displayed.
• PCI bus speed: lspci can show the bus speed (e.g., 33MHz, 66MHz, or PCIe link speed) when using verbose modes. The speed is derived from the PCI capabilities registers.
• Device vendor identification: Every PCI device has a vendor ID and device ID. lspci displays the vendor name (e.g., Intel, NVIDIA) by looking up the ID in the PCI ID database (/usr/share/hwdata/pci.ids).

Incorrect Choices

• System battery type: Battery information is not part of the PCI subsystem. It is typically accessed via ACPI or through files in /sys/class/power_supply/. lspci does not provide this data.
• Ethernet MAC address: MAC addresses are associated with network interfaces, not PCI configuration space. While an Ethernet controller is a PCI device, its MAC address is stored in its own EEPROM and is not exposed by lspci. The ip link or ifconfig commands show MAC addresses.