net: shell: Prevent deadlock with net arp command #66518
Merged
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In case one of the networking shell backends is enabled, net arp command could potentially trigger a deadlock, as it locks the ARP mutex before TCP connection mutex, while TCP stack could do this in reverse order (for instance when sending ACK or retransmission).
Mitigate this, by forcing a separate TX thread in such case, so that ARP mutex is no longer accessed with TCP mutex locked.
The PR is an outcome of a discussion in #66287 (comment)