PROBLEM: 5.6.0-rc6 + Realtek RTL8188CUS wifi dongle: 8051 reset failed!

[AC]

I am on Debian 10.3 stable i386, running a custom-compiled kernel (I compile weekly, when new rc releases drop).

I keep the following USB wifi dongle connected to this machine:

ID 050d:1102 Belkin Components F7D1102 N150/Surf Micro Wireless Adapter v1000 [Realtek RTL8188CUS]


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The problem: 

As of 5.6.0-rc6, booting up with the dongle connected returns a number of dmesg complaints:

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[    9.448337] rtl8192cu: MAC auto ON okay!          [    9.579025] rtl8192cu: Tx queue select: 0x05      [   10.475308] rtl8192c_common: Polling FW ready fail! REG_MCUFWDL:0x00030006.                            [   10.478213] rtl8192c_common: Firmware is not ready to run!                                             [   10.960093] rtl8192cu: 8051 reset failed!.........................                                     [   10.971027] rtl8192cu: MAC auto ON okay!          [   11.101691] rtl8192cu: Tx queue select: 0x05

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Occasionally, this results in a timeout while trying to reach network.target (systemd). 

Afterwards, there's endless dmesg noise Re: rtl8192cu:

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[11391.204555] rtl8192cu: Tx queue select: 0x05      [11707.050480] rtl8192cu: MAC auto ON okay!          [11707.181118] rtl8192cu: Tx queue select: 0x05      [12023.057056] rtl8192cu: MAC auto ON okay!          [12023.187727] rtl8192cu: Tx queue select: 0x05
[12339.060183] rtl8192cu: MAC auto ON okay!          [12339.199316] rtl8192cu: Tx queue select: 0x05      [12655.054140] rtl8192cu: MAC auto ON okay!          [12655.184789] rtl8192cu: Tx queue select: 0x05      [12971.053948] rtl8192cu: MAC auto ON okay!          [12971.184600] rtl8192cu: Tx queue select: 0x05      [13287.062712] rtl8192cu: MAC auto ON okay!          [13287.193363] rtl8192cu: Tx queue select: 0x05      [13603.065987] rtl8192cu: MAC auto ON okay!          [13603.196641] rtl8192cu: Tx queue select: 0x05      [13919.066617] rtl8192cu: MAC auto ON okay!          [13919.197270] rtl8192cu: Tx queue select: 0x05      [14235.060621] rtl8192cu: MAC auto ON okay!          [14235.191277] rtl8192cu: Tx queue select: 0x05      [14551.055104] rtl8192cu: MAC auto ON okay!          [14551.185741] rtl8192cu: Tx queue select: 0x05      [14867.051799] rtl8192cu: MAC auto ON okay!          [14867.182451] rtl8192cu: Tx queue select: 0x05      [14878.855070] perf: interrupt took too long (7897 > 7896), lowering kernel.perf_event_max_sample_rate to 25250

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There are large swaths of this in dmesg.