hesela.devSCSI deferred error
A SCSI deferred error reports a failure of previously acknowledged work through a later eligible command.
Buffered writes and immediate operations can return GOOD before their underlying work finishes. A later report must therefore be distinguished from an error of the command receiving it. Preserve autosense with its original status rather than assuming a later REQUEST SENSE will reproduce it. [1]
Linux v6.12 recognizes fixed-format response codes 70h/71h and descriptor-format codes 72h/73h as current/deferred pairs. The sense key alone does not encode this distinction. The Information field additionally needs validity and command-specific interpretation. [2]
A nonzero printed Information number alone does not establish a residual. Hesela's ten synthetic decoder inputs exercise timing, format and validity independently. All returned decoder status zero, including eight Medium Error inputs: this is an offline decoding result, not successful tape I/O. [1] [3]
Relations
Citations
- IBM 3592 SCSI Reference GA32-0968-07 (2026), sections 4.7, 4.14 and 6.8.2
- Linux v6.12 st_analyze_sense: response format, deferred flag and information validity
- Hesela: ten offline synthetic sg_decode_sense observations, exact bytes, outputs and hashes