UFS rw support fails with 3.19.0-26-generic

[bjcheny]

Hi guys,

I'd like to enable rw support for ufs file system with kernel 3.19.0-26-generic.

Basically, I follow steps as below from http://oz123.github.io/writings/2012-11-26-enable-ufs-write-support-debian/

sudo apt-get build-dep --no-install-recommends linux-image-$(uname -r)

mkdir ufs_rw
cd ufs_rw

apt-get source linux-image-$(uname -r)
cp -v /usr/src/linux-headers-$(uname -r)/Module.symvers .

cd linux-*/
cp -v /boot/config-$(uname -r) .

make EXTRAVERSION=-4 O=~/ufs_rw oldconfig

sed -i 's/# CONFIG_UFS_FS_WRITE is not set/CONFIG_UFS_FS_WRITE=y/' ~/ufs_rw/.config

make EXTRAVERSION=-4 O=~/ufs_rw prepare

make EXTRAVERSION=-4 O=~/ufs_rw outputmakefile

make EXTRAVERSION=-4 O=~/ufs_rw archprepare

make EXTRAVERSION=-4 O=~/ufs_rw modules SUBDIRS=scripts

make EXTRAVERSION=-4 O=~/ufs_rw modules SUBDIRS=fs/ufs

I get ufs.ko under ufs_rw/fs/ufs and try it with below commands.

modprobe nbd

qemu-nbd -c /dev/nbd0 freebsd10u1x64

mount -t ufs -o ufstype=ufs2,rw /dev/nbd0p2 /mnt

There is no error or warning when I run

mount -t ufs -o ufstype=ufs2,rw /dev/nbd0p2 /mnt

However, when I try to write something to /mnt or even umount /mnt, there is kernel panic.

And further more, the way above works for 3.8.0-34-generic/3.11.0-26-generic.

That means I can read/write correctly with ufs2 file system.

It breaks with 3.19.0-26-generic, from my view.

Please let me know if more info is needed.

[Brad Figg (brad-figg)]

This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:

apport-collect 1501623

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Joseph Salisbury (jsalisbury)]

We would like to review the details of the panic. Do you have a screen shot, digital image or the text details of the panic that you could provide?

[bjcheny (companycy)]

Sorry for late reply.

Attach call stack from var/log/syslog.

Please help review it.

[bjcheny (companycy)]

One more log which is generated by remount command

mount -t ufs -o ufstype=ufs2,remount,rw /dev/nbd0p2 /mnt

Fyi.

[bjcheny (companycy)]

Hi ,

Is there any progress?

[bjcheny (companycy)]

Hi guys,

I have got a patch migrating from 3.11 version, and it works for 3.19.25/26.

It could be a regression. The patch looks like:

--- ufs/super.c 2015-09-26 17:18:46.000000000 +0800
+++ work/super.c 2015-10-12 23:46:40.964962685 +0800
@@ -805,6 +805,7 @@
        UFSD("flag %u\n", (int)(sb->s_flags & MS_RDONLY));

        mutex_init(&sbi->mutex);
+ mutex_init(&sbi->s_lock);
        spin_lock_init(&sbi->work_lock);
        INIT_DELAYED_WORK(&sbi->sync_work, delayed_sync_fs);
        /*

Pls help review this patch.

Meanwhile, source tar downloaded by 3.19.0-26 quite matches what I get from kernel, though they both look like 3.19.8.

root@compiler-14:~# diff linux-3.19.8/Makefile ~/ufs_rw/linux-lts-vivid-3.19.0/Makefile
4,5c4,5
< EXTRAVERSION =
< NAME = Diseased Newt
---
> EXTRAVERSION = -ckt5
> NAME = Sedated Swine
/// ...

At least the header is different, which is related to this patch.
root@compiler-14:~# diff linux-3.19.8/fs/ufs/ufs.h ~/ufs_rw/linux-lts-vivid-3.19.0/fs/ufs/
32a33
> struct mutex s_lock;

Regards

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu Vivid) because there has been no activity for 60 days.]