Bug 743136
| Summary: | grub2-mkconfig emits ERROR: unsupported sector size 4096 | ||||||
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| Product: | [Fedora] Fedora | Reporter: | Bayard R. Coolidge <n1ho> | ||||
| Component: | grub2 | Assignee: | Peter Jones <pjones> | ||||
| Status: | CLOSED NEXTRELEASE | QA Contact: | Fedora Extras Quality Assurance <extras-qa> | ||||
| Severity: | unspecified | Docs Contact: | |||||
| Priority: | unspecified | ||||||
| Version: | 16 | CC: | awilliam, dennis, mads, myroslav, pjones, the.ridikulus.rat, vgulch | ||||
| Target Milestone: | --- | Keywords: | CommonBugs | ||||
| Target Release: | --- | ||||||
| Hardware: | x86_64 | ||||||
| OS: | Linux | ||||||
| Whiteboard: | https://fedoraproject.org/wiki/Common_F16_bugs#4k-sectors | ||||||
| Fixed In Version: | Doc Type: | Bug Fix | |||||
| Doc Text: | Story Points: | --- | |||||
| Clone Of: | Environment: | ||||||
| Last Closed: | 2012-04-30 22:41:08 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: | |||||||
| Attachments: |
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Description
Bayard R. Coolidge
2011-10-04 00:27:17 UTC
Do grub2-mkconfig work despite these errors? How do grub.cfg look like? I guess most of these errors come from os-prober which is invoked by grub2-mkconfig. Can you try to run 'os-prober' manually? Created attachment 529933 [details]
grub.cfg from newly installed system on a 4096 byte sector 3TB USB drive
So for background here, it seems to be Western Digital which is actually putting drives with 4K sector sizes out into the market, and afaict it seems to be their Green line. Western Digital's term for 4K sector sizes is 'Advanced Format': the marketing info for any drive with this sector size mentions the 'Advanced Format' buzzword. pjones is of the opinion that this has basically never worked without EFI: he expects that prior to F16, grub-legacy would have tried to install itself on disks with 4K sector sizes, but ought to have failed to produce a bootable system. The grub2.cfg attached above is from a newly installed "TC" system. It was installed in the same manner as my original attempt(s). I tried os-prober (after duly checking for last-minute updates) and it emitted: [root@hislap-f16TC bayard]# which os-prober /usr/bin/os-prober [root@hislap-f16TC bayard]# os-prober --help ERROR: unsupported sector size 4096 on /dev/sdc. ERROR: unsupported sector size 4096 on /dev/sdc. ERROR: unsupported sector size 4096 on /dev/sdc. ERROR: unsupported sector size 4096 on /dev/sdc. ERROR: unsupported sector size 4096 on /dev/sdc. ERROR: unsupported sector size 4096 on /dev/sdc. ERROR: unsupported sector size 4096 on /dev/sdc. ERROR: unsupported sector size 4096 on /dev/sdc. ERROR: unsupported sector size 4096 on /dev/sdc. ERROR: unsupported sector size 4096 on /dev/sdc. ERROR: unsupported sector size 4096 on /dev/sdc. ERROR: unsupported sector size 4096 on /dev/sdc. ERROR: unsupported sector size 4096 on /dev/sdc. ERROR: unsupported sector size 4096 on /dev/sdc. ERROR: unsupported sector size 4096 on /dev/sdc. No volume groups found /dev/sda1:Windows XP Media Center Edition:Windows:chain /dev/sda2:Windows NT/2000/XP:Windows1:chain /dev/sda3:Microsoft Windows XP Embedded:Windows2:chain /dev/sdb2:openSUSE 11.4 (x86_64):SuSE:linux /dev/sdc6:Ubuntu 11.10 (11.10):Ubuntu:linux /dev/sdc7:openSUSE 12.1 RC 1 (x86_64):SuSE1:linux Note that it did see my systems on /dev/sda1, /dev/sda2 and /dev/sdb2. (Adam was sending me comments via e-mail and updating this BZ while I was attempting to insert this comment, so forgive the disorder!) Seagate also has 4K disks, and also call it 'Advanced Format'. Their Barracuda Green drives appear to use this, inc. the 1.5TB model. Hitachi's green-style drives (high capacity, low spindle speed) also appear to use 'Advanced Format', according to the comments on http://ncix.com/products/?sku=59651&vpn=0S03230&manufacture=Hitachi . (Reintroduce lost CommonBugs keyword) So, 3 issues here: 0: The 4k disk was sdb but now it showed up as sdc - ok, no problem 1: os-prober issues warnings (but is able to detect openSUSE 12.1 anyway) 2: grub2-mkconfig fails to detect it anyway 3: booting from 4k drives might not work anyway (which could explain why they are ignored) ??? 0.) Not an issue - typical "bus" renumbering/redesignation depending on if it booted off of a DVD, etc. 1.) Yes, the openSUSE 12.1 issue isn't an issue anymore, but os-prober seems to be allergic to 4k drives, which is an issue (IMNSHO). 2.) grub2-mkconfig seems to run correctly, except for os-prober's issues. 3.) Booting from 4k drives wasn't explicitly disallowed by any documentation to date, and apparently GRUB2 won't be able to boot them. However, the installation processes seems to imply that a boot block was created and installed. What's in the remaining 4096-512=3584 bytes of the boot sector is a mystery to me. And, it's quite probable that this corner case can't be resolved since the BIOS on my particular laptop is most likely set up to deal with just 512 byte boot blocks anyway; it's not EFI-capable, either. (Ironically, it appears that this laptop is dying, too, after almost 4 years - long story about heat dissipation in this particular model). It appears that it would take a significant amount of engineering time to develop a variant of GRUB2 that writes to a 4k sector, and can be read by a BIOS designed for 512 byte sectors which can then successfully boot such a drive. (In reply to comment #7) > 2.) grub2-mkconfig seems to run correctly, except for os-prober's issues. Ok, that did for unknown reasons change between the original report and comment 2 - I failed to notice that. I suggest you file a separate issue for os-prober. The remaining issue here is thus "grub2 can't boot from 4k disks". Some quick googling hints that it should work, but the functinality has not been released yet and is not included in 1.99: revno: 3394 committer: Vladimir 'phcoder' Serbinenko <phcoder> branch nick: grub timestamp: Mon 2011-07-25 08:14:34 +0200 message: Support ATA disks with 4K sectors. * include/grub/ata.h (grub_ata): New member log_sector_size. * grub-core/disk/ata.c (grub_ata_dumpinfo): Show sector size. (grub_ata_identify): Read sector size. (grub_ata_readwrite): Use log_sector_size rather than hardcoded value. pjones: should we backport that fix? -- Fedora Bugzappers volunteer triage team https://fedoraproject.org/wiki/BugZappers I doubt it will be backported to f16 now, but the patch is included in the version used in f17. grub2-2.0-0.24.beta4.fc17 includes the change from comment 8 and has been pushed to f17 stable. Closing. |