Thanks for the review. Both issues are fixed in v2: https://lore.kernel.org/bpf/[email protected]/
Per-entry lookup errors now retain the existing error markers and do not abort the dump. This covers PERF_EVENT_ARRAY, including when it is an inner map, where element lookup is unsupported. Traversal now queues deduplicated inner-map IDs and opens, dumps and closes each inner map in turn. It keeps the selected root FDs open and requires only one additional map FD. Unchanged outer entries retain their inner maps. The documentation explains that IDs are resolved when visited and that concurrent updates mean the dump is not an atomic snapshot. Failure to open a queued ID still returns an error and closes the JSON containers. The series adds four regression subtests: ordinary and nested perf event arrays, plus JSON and plain dumps of 64 distinct inner maps under RLIMIT_NOFILE=32. All four fail with v1. All 12 subtests pass with v2 in a matching-kernel VM, with zero skips. An injected ENOENT at the deferred inner-map FD lookup also returns failure with parseable JSON. Best regards, Tianyi
