On Mon, 2007-11-19 at 12:50 -0800, Andrew Morton wrote: > On Mon, 19 Nov 2007 05:44:01 -0800 (PST) > bugme-daemon@xxxxxxxxxxxxxxxxxxx wrote: > > > http://bugzilla.kernel.org/show_bug.cgi?id=9405 > > > > Summary: iSCSI does not implement ordering guarantees required by > > e.g. journaling filesystems > > Product: IO/Storage > > Version: 2.5 > > KernelVersion: 2.6.23.1 > > Platform: All > > OS/Version: Linux > > Tree: Mainline > > Status: NEW > > Severity: high > > Priority: P1 > > Component: SCSI > > AssignedTo: io_scsi@xxxxxxxxxxxxxxxxxxxx > > ReportedBy: bart.vanassche@xxxxxxxxx > > > > > > Most recent kernel where this bug did not occur: (new issue) > > Distribution: any > > Hardware Environment: (does not apply) > > Software Environment: (does not apply) > > Problem Description: The sd (SCSI disk) driver ignores block device barriers > > (REQ_HARDBARRIER). The iSCSI code in the kernel sends all iSCSI commands with > > flag ISCSI_ATTR_SIMPLE to the iSCSI target. This means that the target may > > reorder these commands. Since a.o. correct operation of journaling filesystems > > depends on being able to enforce the order of certain block write operations, > > not enforcing write ordering is a bug. This can be solved by either adding > > support for REQ_HARDBARRIER in the sd device or by replacing ISCSI_ATTR_SIMPLE > > by ISCSI_ATTR_ORDERED. > > > > Steps to reproduce: Source reading of drivers/scsi/sd.c and > > drivers/scsi/libiscsi.c. > > > > References: SCSI Architecture Model - 3, paragraph 8.6 > > (http://www.t10.org/ftp/t10/drafts/sam3/sam3r14.pdf). > > > > (does iscsi have a maintainer?) Yes, mike christie And please close this as invalid. FS ordering guarantees in linux aren't done via ordered tags. James - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
