When writing queries to >control, flags are parsed 1st, since they are the only required field. So if the flags draw an error, then keyword errors aren't reported. This can be mildly confusing/annoying, so explain it instead. This note could be moved up to just after the grammar id's the flags, and before the match-spec is detailed. Opinions ? Signed-off-by: Jim Cromie <jim.cromie@xxxxxxxxx> --- Documentation/admin-guide/dynamic-debug-howto.rst | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/Documentation/admin-guide/dynamic-debug-howto.rst b/Documentation/admin-guide/dynamic-debug-howto.rst index 7b570f29ae98..ccf3704f2143 100644 --- a/Documentation/admin-guide/dynamic-debug-howto.rst +++ b/Documentation/admin-guide/dynamic-debug-howto.rst @@ -106,6 +106,16 @@ The match-spec's select *prdbgs* from the catalog, upon which to apply the flags-spec, all constraints are ANDed together. An absent keyword is the same as keyword "*". +Note: because the match-spec can be empty, the flags are checked 1st, +then the pairs of keyword values. Flag errs will hide keyword errs: + + bash-5.2# ddcmd mod bar +foo + dyndbg: read 13 bytes from userspace + dyndbg: query 0: "mod bar +foo" mod:* + dyndbg: unknown flag 'o' + dyndbg: flags parse failed + dyndbg: processed 1 queries, with 0 matches, 1 errs + A match specification is a keyword, which selects the attribute of the callsite to be compared, and a value to compare against. Possible keywords are::: -- 2.45.2
