Sorry, sys_arch wasn't my piece of code and I didn't hit on idea to check this.
As you said, there are two options: full mbox and non-empty queue while deleting it. Debbug shows sys_mbox_trypost tries to post to full queue. -- View this message in context: http://lwip.100.n7.nabble.com/lwIP-1-4-1-server-s-SYN-flood-hang-no-backlog-tp23116p23166.html Sent from the lwip-users mailing list archive at Nabble.com. _______________________________________________ lwip-users mailing list lwip-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/lwip-users