net/realtek-re-kmod panics with debug kernel

From: Andrea Venturoli <>
Date: Tue, 08 Jun 2021 06:57:52 UTC

I've got a 12.2/amd64 desktop pc with the following on the motherboard:
> re0: <RealTek 8168/8111 B/C/CP/D/DP/E/F/G PCIe Gigabit Ethernet> port 0xe000-0xe0ff mem 0xf7404000-0xf7404fff,0xf7400000-0xf7403fff irq 33 at device 0.0 on pci4

Unfortunately it's not easy to plug a new PCI NIC into it, and since re0 
tends to hang on load, I'm using the driver from ports.

Yesterday I compiled a kernel with all debug features in order to 
analyze some (probably unrelated) deadlock. Alas, with such features 
enabled, the machine panics at boot with:
> _mtx_lock_sleep: recursed on non-recursive mutex re0 0 if_re.c:7085

I don't have full data now, but I can reproduce and try to get it, if 
it's useful.

Is it worth opening a bug report?

  bye & Thanks