On Tue, 2017-08-15 at 02:16 +0000, Tangchen (UVP) wrote: > But I'm not using mq, and I run into these two problems in a non-mq system. > The patch you pointed out is fix for mq, so I don't think it can resolve this problem. > > IIUC, mq is for SSD ? I'm not using ssd, so mq is disabled. Hello Tangchen, Please post replies below the original e-mail instead of above - that is the reply style used on all Linux-related mailing lists I know of. From https://en.wikipedia.org/wiki/Posting_style: A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail? Regarding your question: sorry but I quoted the wrong commit in my previous e-mail. The commit I should have referred to is 255ee9320e5d ("scsi: Make __scsi_remove_device go straight from BLOCKED to DEL"). That patch not only affects scsi-mq but also the single-queue code in the SCSI core. blk-mq/scsi-mq was introduced for SSDs but is not only intended for SSDs. The plan is to remove the blk-sq/scsi-sq code once the blk-mq/scsi-mq code works at least as fast as the single queue code for all supported devices. That includes hard disks. Bart.
