Old approach patched vnode-type assertion BLs (CBZ→panic). New approach
scans backward from function end for the shared MOV W0,#1 kill return
before the LDP x29,x30 epilogue and changes it to MOV W0,#0. Single
instruction converts all 5+ kill paths to success. Boot-tested OK.
Root cause: "most-called BL target" heuristic in _proc_info picked copyio
(4 calls, 0x28C bytes) over the real _proc_security_policy (2 calls,
0x134 bytes). Lowered size filter threshold from 0x300 to 0x200 to
correctly exclude utility functions like copyio. Boot-tested: PASS.
The original selector24 patches (NOP ldr + NOP bl) broke the hash flags
extraction, causing the consistency check to fail. The second attempt
(return 0x130A1) also failed because the return code semantics were
inverted — byte 1 != 0 means FAIL, not success.
Correct approach: insert `mov w0, #0xa1; b <epilogue>` after the prologue.
0xA1 has byte 1 = 0 which the caller checks via `tst w0, #0xff00` as PASS.
Update AGENTS.md
move selector24 bypass from txm_jb.py to txm_dev.py, delete TXMJBPatcher
Selector24 CS validation bypass now applies to both dev and JB variants
via txm_dev.py. The separate txm_jb.py patcher is removed since it had
no other patches. Dev boot chain: 47→49 patches.
Create txm_fullchain_analysis.md
