__wt_verbose_dump_cache() walks every btree dhandle to report per-file page counts. That walk took a SIGSEGV, killing a process that was only trying to report diagnostics.

Identical crash frames in three separate cores:

#0 __wt_page_in_func           bt_read.c:553      <- btree = S2BT(session)
#1 __wt_page_swap_func         btree_inline.h:2630   (held=0x0)
#2 __tree_walk_internal        bt_walk.c:337
#3 __wt_tree_walk              bt_walk.c:431
#4 __verbose_dump_cache_single evict_verbose.c:63
#5 __verbose_dump_cache_apply  evict_verbose.c:152
#6 __wt_verbose_dump_cache     evict_verbose.c:193
#7 __conn_debug_info           conn_api.c:1437

Observed effects: the dump truncated before cache dump: total found and the per-file dirty mass, and the intended clean __wt_abort() became a SIGSEGV, so Build Baron extracts a Segmentation Failure fault and the instances misclassify.

Seen in three BFGs, all wiredtiger @ 92445b64, format-stress-test-disagg-switch-data-validation-*:

• BFG-3495446 (ubuntu2004-stress-tests-arm64)
• BFG-3495728 (ubuntu2004-stress-tests)
• BFG-3496860 (ubuntu2004-release-stress-tests)

Reached in all three via format's watchdog calling conn->debug_info.