login: ‰‰panic: pool_p_free: semupl free list modified: page 0xffffff0062f76000; item addr 0xffffff0062f76ee8; offset 0x0=0xdead4111 Stopped at db_enter+0xa: popq %rbp TID PID UID PRFLAGS PFLAGS CPU COMMAND *383039 76608 0 0x14000 0x200 0 systqmp db_enter() at db_enter+0xa panic() at panic+0x147 pool_p_free(ffffffff81e9f0c8,0) at pool_p_free+0x18e pool_gc_pages(ffffffff81468630) at pool_gc_pages+0x1d5 taskq_thread(0) at taskq_thread+0x72 end trace frame: 0x0, count: 10 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs.