https://bugzilla.novell.com/show_bug.cgi?id=229260#c33
--- Comment #33 from Tejun Heo
One possible regression point between IDE and libata is ATAPI DMA: For IDE, only Read/Write commands with multiple of 512 bytes are done in ATAPI DMA. However, in libata, _all_ packet command are default with ATAPI DMA.
Maybe this SH-S162L drive doesn't like "INQUIRY" by ATAPI DMA?
Argh... Right. My stupid eyes somehow filtered out if (info->dma) in cdrom_start_packet_command() so I was thinking IDE was doing it using DMA too. Thanks for the enlightenment. :-) It seems, IDE uses DMA for ATAPI devices for 1. READ/WRITE requests which are aligned to queue_hardsect_size() 2. SG request with BIO where length is aligned to 16bytes && starting address is aligned to DMA engine alignment (of course). I think we should just follow what IDE has been doing for years. Thanks, this solves the mysterious three INQUIRY timeout cases I found out from last week. -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.