Bug 626374
| Summary: | fdisk incorrectly checks alignment for non-512-byte *logical* sectors. | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 6 | Reporter: | Karel Zak <kzak> |
| Component: | util-linux-ng | Assignee: | Karel Zak <kzak> |
| Status: | CLOSED ERRATA | QA Contact: | qe-baseos-daemons |
| Severity: | medium | Docs Contact: | |
| Priority: | low | ||
| Version: | 6.1 | CC: | azelinka, msnitzer, rvokal, yanwang |
| Target Milestone: | rc | ||
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | util-linux-ng-2.17.2-9.el6 | Doc Type: | Bug Fix |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2011-05-19 14:06:20 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2011-0699.html |
Copy & past from upstream: # modprobe scsi_debug dev_size_mb=1024 sector_size=4096 # fdisk /dev/sdb Command (m for help): n Command action e extended p primary partition (1-4) p Partition number (1-4, default 1): Using default value 1 First sector (256-262143, default 256): 257 Last sector, +sectors or +size{K,M,G} (257-262143, default 262143): +100M Command (m for help): p Disk /dev/sdb: 1073 MB, 1073741824 bytes 32 heads, 32 sectors/track, 256 cylinders, total 262144 sectors Units = sectors of 1 * 4096 = 4096 bytes Sector size (logical/physical): 4096 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 262144 bytes Disk identifier: 0x16db2bb0 Device Boot Start End Blocks Id System /dev/sdb1 257 25855 102396 83 Linux Partition 1 does not start on physical sector boundary. ^^^^^^^^ The warning is nonsense. The logical and physical sector size is the same. It means that every LBA is always aligned to physical sector boundary. Note that this bug does not mean that fdisk produces unaligned partitions. The problem is that fdisk forces to use bigger gaps between aligned LBAs, for example: correctly aligned LBA are: 256, 257, 258, ... [N+1] fdisk assumes: 256, 264, 272, ... [N+(sector_size/512)] Bug fix is pretty simple: - unsigned long long offset = (lba << 9) & (granularity - 1); + unsigned long long offset = (lba * sector_size) & (granularity - 1);