Re: Broken nilfs2 filesystem

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi Anton,

On Wed, 2013-05-22 at 22:33 +0200, Anton Eliasson wrote:
> Greetings!
> It pains me to report that my /home filesystem broke down today. My 
> system is running Arch Linux 64-bit. The filesystem resides on a Crucial 
> M4 256 GB SSD, on top of a LVM2 volume. The drive and filesystem are 
> both around six months old. Partition table and error log excerpts are 
> at the bottom of this e-mail. Full logs are available upon request.
> 
> I am providing this information as a bug report. I have no reason to 
> suspect the hardware but I cannot exclude it either. If you (the 
> developers) are interested in troubleshooting this for prosperity, I can 
> be your hands and run whatever tools are required. If not, I'll reformat 
> the filesystem, restore the data from backup and forget that this happened.
> 
> In case the formatting gets mangled, this e-mail is also available at 
> What happened today, in chronological order:
> 
> ~18:00
> ======
> I am troubleshooting some issues that turn out to be caused by a wrongly 
> configured system clock. The RTC (hardware clock) is set to local time 
> (UTC+2) but the OS is configured to treat the RTC as UTC. This is 
> because it was set to UTC previously, but then I reinstalled Windows 
> which promptly reset it to local time.
> 
> This set the mtime of some files in both / and /home to dates in the 
> future. When I discovered this, I `touch`ed all affected files (`touch 
> now; sudo find / /home -xdev -newer now -exec touch {} \;`) to reset 
> their mtime and rebooted the system. I do not know if this is relevant; 
> if not, it makes reading the log files more fun.
> 
> I then launch my command line backup program "bup", Firefox and some 
> other apps.
> 
> ~18:50-19:00
> ============
> Firefox freezes. The system keeps running but I can't launch new 
> programs. It looked like all I/O broke down. However, bup kept running. 
> I left the computer alone for perhaps 30-60 min.
> 

So, as I understand, a reproducing path is:
(1) set mtime of some files in the future;
(2) touch all affected files;
(3) reboot the system;
(4) launch backup program "bup", Firefox and some other apps.

I think that it makes sense to try this reproducing path. But we had
reports about the issue with likewise symptoms
(nilfs_bmap_lookup_contig: broken bmap) for the case of 4 KB block size
from other users. Unfortunately, I can't reproduce such issue for the
case of 4 KB blocks size earlier. As I feel the clear reproducing path
is crucial for this issue.

I understand that it can be hard to reproduce the issue again. But,
anyway, have you opportunity to try to reproduce the issue on another
NILFS2 partition on your side?

Anyway, I am going to reproduce the issue by this reproducing path on my
side.

> ~20:00
> ======
> When I came back, bup hade frozen (/var/log/messages at 18:53:31).[1] I 
> restart X by pressing Alt+SysRq+K (/var/log/messages at 20:06:33) and 
> return to the login screen. The system freezes during login though, 
> probably because /home had probably been mounted read only). So I reboot 
> using Alt+SysRq+REISUB (/var/log/messages at 20:07:05). I noticed some 
> I/O errors during shutdown.
> 
> After the reboot there are no immediate signs of disaster. I launch bup 
> again. Some time later, /home remounts as read only. I notice that bup 
> has reported I/O errors while reading some files in /home.[2] dmesg and 
> /var/log/kern.log contains errors mentioning "bad btree node" and 
> "nilfs_bmap_lookup_contig: broken bmap".[3]
> 

Now we have patch for overcome the freezing of system after such issue:
http://www.mail-archive.com/linux-nilfs@xxxxxxxxxxxxxxx/msg01614.html.

With the best regards,
Vyacheslav Dubeyko.



--
To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Filesystem Development]     [Linux BTRFS]     [Linux CIFS]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux SCSI]

  Powered by Linux