Red Hat Bugzilla – Bug 768481
Kernel panic - not syncing: VFS: Unable to mount root fs
Last modified: 2011-12-19 16:23:06 EST
Description of problem:
Kernel panic at boot.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block (0,0)
Pid:1, comm: swapper/0 Not tainted 3.2.0-0.rc5.git3.1.fc17.x86_64 #1
[<ffffffff81002930>] ? name_to_dev_t+0x770/0xe40
[<ffffffff8167df34>] ? retint_restore_args+0x13/0x13
[<ffffffff81f63c3e>] ? start_kernel+0x3f9/0x3f9
[<ffffffff81688600>] ? gs_change+0x13/0x13
This is very likely caused by the kernel not having an initramfs passed to it. Is there a corresponding initramfs in /boot for this kernel, and is it included in whichever grub configuration file your machine is using?
Do you have anything in /var/log/messages about depmod, new-kernel-pkg, or dracut segfaulting or any out-of-memory errors?
I don't have initramfs for git3 kernel.
This panic is 100% reproducible for me on KVM VMs, exact same backtrace; I've installed one VM directly from the rawhide repo with the F16 installer and upgraded two other VMs. All 3 panic'd on reboot. I am happy to provide access to a VM exhibiting the problem, or anything else I can do to help troubleshoot it, as it's blocking me from verifying a libvirt bug.
I took the dracut suggestion, and downgraded to previous dracut-013-100.git20111021.fc17, then reinstalled kernel. I now have initramfs and boots.
Pretty sure this is this issue:
*** This bug has been marked as a duplicate of bug 768645 ***
Yep, that was it, thanks. The steps in:
got my systems booting again.