Bug 1074667
| Summary: | Boot stops with "alloc magic is broken at 0x..." | ||
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| Product: | [Fedora] Fedora | Reporter: | Peter Trenholme <PTrenholme> |
| Component: | grub2 | Assignee: | Peter Jones <pjones> |
| Status: | CLOSED EOL | QA Contact: | Fedora Extras Quality Assurance <extras-qa> |
| Severity: | high | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | 22 | CC: | bcl, dennis, gansalmon, itamar, jonathan, kernel-maint, lkundrak, madhu.chinakonda, mads, mchehab, pjones |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | x86_64 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2016-07-19 19:01:09 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
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Description
Peter Trenholme
2014-03-10 19:26:04 UTC
If you're seeing that error message, the kernel isn't even started. If there's something particular about the kernel binary being loaded that hiccups grub that would be interesting to know but it would still be a grub issue. Yes, I hadn't thought that through. If the MBR is bonked, clearly it isn't a kernel issue. I've been looking for differences between GRUB on my two systems, and noticed something strange: (Note: My F-20 root is mounted as /Fedora; / is Rawhide) # diff `locate -b grub2-mkimage` Binary files /Fedora/usr/bin/grub2-mkimage and /usr/bin/grub2-mkimage differ # ll `locate -b grub2-mkimage` -rwxr-xr-x. 1 root root 188792 Aug 10 2013 /Fedora/usr/bin/grub2-mkimage -rwxr-xr-x. 1 root root 188648 Aug 10 2013 /usr/bin/grub2-mkimage # file `locate -b grub2-mkimage` /Fedora/usr/bin/grub2-mkimage: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.32, BuildID[sha1]=01d5b3f3758aa65de83b13885e723c0288b34147, stripped /usr/bin/grub2-mkimage: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.32, BuildID[sha1]=01d5b3f3758aa65de83b13885e723c0288b34147, stripped How is it that the binaries a different when the build ID sha1 values are identical? Not that it makes any difference: replacing all the grub2* files in /usr/bin with copies from my /Fedora/usr/bin and rerunning the grub2-install script still produced an unbootable MBR with the same error message. Another attempt: I booted into the F-20 system and ran grub2-install from there, pointing it to the Rawhide /boot. No joy: The MBR was still unbootable. (Tried this two ways: Once with a -d pointing to the Rawhide /boot/grub2 directory, once without a -d option.) All of the above seams to suggest grub has hard-coded something about the kernel that has been changed. By the way, I made a mistake with the -d value the first time I tried it, and GRUB had no problem booting into rescue mode, so the problem is only, I think, in the "magic number" check. I think I may have found the source to my problem. (But I hope I haven't!) During my last Rawhide update I noticed an message I hadn't seen before: grub2-editenv: error: environment block too small. So I checked this and, sure enough, grubenv was only 968 bytes. After I fixed that so it was 1024 bytes, the reboot using /dev/sda executed flawlessly. Now, if that was, in fact, the cause of an unbootable MBR, I'd be VERY surprised. But, for whatever reason (maybe the rc7 kernel fixed something?), my system now seems, once again, to be bootable from either MBR. (I.e., sda or sdb) (I also noticed, in /var/log/messages, that grub2 is now running at a higher debug level, but that, too, should not have had any impact on an unbootable MBR.) Note: I did NOT rerun "grub-install /dev/sda" so, theoretically, nothing has been changed in the MBR on that device. Thus, a device that was unbootable earlier this morning is now bootable. (So, is it true that Linux is magic? Or just Fedora? Or is this just a Heisenbug?) This bug appears to have been reported against 'rawhide' during the Fedora 22 development cycle. Changing version to '22'. More information and reason for this action is here: https://fedoraproject.org/wiki/Fedora_Program_Management/HouseKeeping/Fedora22 Fedora 22 changed to end-of-life (EOL) status on 2016-07-19. Fedora 22 is no longer maintained, which means that it will not receive any further security or bug fix updates. As a result we are closing this bug. If you can reproduce this bug against a currently maintained version of Fedora please feel free to reopen this bug against that version. If you are unable to reopen this bug, please file a new report against the current release. If you experience problems, please add a comment to this bug. Thank you for reporting this bug and we are sorry it could not be fixed. |