Re: Major KVM issues with kernel 4.5 on the host

Borislav Petkov
2016-03-17T18:11:56Z

+ kvm ML.

Do you have any funky messages in host's dmesg ? Can you upload a full
dmesg from both a good and a bad host kernel?

On Thu, Mar 17, 2016 at 05:54:35PM +0100, Marc Haber wrote:
> Hi,
>
> I have a (semi-productive[1]) system ("host") running Debian unstable.
> On this system, a few VMs (Debian unstable, Debian testing) ("vm1",
> "vm2", "vm3") are running. I roll my own kernels and take vanilla
> upstream sources. No distribution patches.
>
> Since host was updated to Kernel 4.5, the VMs have started acting up.
> All of them. The range of strangeness begins with "relocation error,
> system halted" on system startup, corrupted data files on disk,
> filesystems remounted read-only, libraries rejected with "invalid ELF
> format", binaries segfaulting all of a sudden. Downgrading host to
> kernel 4.4.5 magically fixed all those issues.
>
> Going back to 4.5 lets the issues reappear. Here, for example, ext4 fs
> errors, logged in one of the VMs:
>
> Mar 17 17:39:57 spinturn kernel: EXT4-fs error (device dm-0): ext4_lookup:1602: inode #415065: comm aide: deleted inode referenced: 546538
> Mar 17 17:39:57 spinturn kernel: EXT4-fs error (device dm-0): ext4_lookup:1602: inode #415065: comm aide: deleted inode referenced: 546530
> Mar 17 17:39:57 spinturn kernel: EXT4-fs error (device dm-0): ext4_iget:4269: inode #546543: comm aide: bad extra_isize (44800 != 256)
> Mar 17 17:39:58 spinturn kernel: EXT4-fs error (device dm-0): ext4_iget:4466: inode #546568: comm aide: bogus i_mode (144)
> Mar 17 17:39:58 spinturn kernel: EXT4-fs error (device dm-0): ext4_lookup:1602: inode #546548: comm aide: deleted inode referenced: 546564
> Mar 17 17:39:58 spinturn kernel: EXT4-fs error (device dm-0): ext4_lookup:1602: inode #546548: comm aide: deleted inode referenced: 546562
> Mar 17 17:39:58 spinturn kernel: EXT4-fs error (device dm-0): ext4_iget:4269: inode #546563: comm aide: bad extra_isize (6464 != 256)
> Mar 17 17:39:58 spinturn kernel: EXT4-fs error (device dm-0): ext4_iget:4466: inode #546561: comm aide: bogus i_mode (0)
> Mar 17 17:39:58 spinturn kernel: EXT4-fs error (device dm-0): ext4_iget:4269: inode #546529: comm aide: bad extra_isize (1152 != 256)
> Mar 17 17:39:58 spinturn kernel: EXT4-fs error (device dm-0): ext4_xattr_block_get:297: inode #546359: comm aide: bad block 677784
>
> I'm going to try reproducing the issue on a less "important" machine
> so that bisecting is less painful, but maybe you guys have an idea
> what's going wrong here.
>
> jftr, kernel 4.5 in guest and in standalone systems seems to be
> unproblematic.
>
> Greetings
> Marc
>
>
> [1] my main workstation, running enough services for the local network
> that disturbances in its operation cause reasonable discomfort, but not the
> Enterprise kind of "productive"
>
> --
> -----------------------------------------------------------------------------
> Marc Haber | "I don't trust Computers. They | Mailadresse im Header
> Leimen, Germany | lose things." Winona Ryder | Fon: *49 6224 1600402
> Nordisch by Nature | How to make an American Quilt | Fax: *49 6224 1600421
>

--
Regards/Gruss,
Boris.

ECO tip #101: Trim your mails when you reply.