I installed a new GPU. Now my on-board ethernet adapter has a different PCI slot number and all my iptables rules are broken.
With my old GPU, which was quite old, the ethernet adapter was device 02:00.0 and the GPU was device 01:00.0.
What are these new "PCI Bridge" devices?
What determines the PCI Express location of something on-board? The motherboard didn't change, only the thing in the first PCI Express slot did.
$ lspci
...
01:00.0 PCI bridge: Advanced Micro Devices, Inc. [AMD/ATI] Navi 10 XL Upstream Port of PCI Express Switch (rev c1)
02:00.0 PCI bridge: Advanced Micro Devices, Inc. [AMD/ATI] Navi 10 XL Downstream Port of PCI Express Switch
03:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Navi 24 [Radeon RX 6400/6500 XT/6500M] (rev c1)
03:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Navi 21/23 HDMI/DP Audio Controller
04:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 0c)