Re: linux-next: Tree for Feb 4

Sedat Dilek
2015-02-04T16:06:51Z

On Wed, Feb 4, 2015 at 4:58 PM, Martin K. Petersen
<martin.petersen@oracle.com> wrote:
>>>>>> "Sedat" == Sedat Dilek <sedat.dilek@gmail.com> writes:
>
>>>>>> I am seeing the following in my logs several times...
>>>>>>
>>>>>> Feb 4 02:53:13 fambox kernel: [15507.397482] blk_update_request:
>>>>>> I/O error, dev loop0, sector 21261344 Feb 4 02:53:13 fambox
>>>>>> kernel: [15507.397531] loop0: DISCARD failed. Manually zeroing.
>
> Sedat> What's the plan... s/pr_warn/pr_debug ?
>
> The rationale here is that we'd like to log (once) if discard or write
> same fail on a given device.
>
> In SCSI we disable these commands if they get failed by the storage. But
> it looks like loop keeps advertising discard support after a failure.
>
> Is your loop device encrypted? Do you know why the discard is failing?
>

No, but I am here on a so-called WUBI installation which triggered
some bugs being an exotic installation.
My Ubuntu/precise is a 18GiB image laying on my Win7 partition (/dev/sda2).

How can I check or debug the discard failing?

- Sedat -

P.S.: Some diagnostics

$ LC_ALL=C df -T
Filesystem Type 1K-blocks Used Available Use% Mounted on
rootfs rootfs 17753424 15663216 1165332 94% /
udev devtmpfs 1959324 4 1959320 1% /dev
tmpfs tmpfs 393888 904 392984 1% /run
/dev/sda2 fuseblk 465546236 161295260 304250976 35% /host
/dev/loop0 ext4 17753424 15663216 1165332 94% /
none tmpfs 5120 4 5116 1% /run/lock
none tmpfs 1969428 176 1969252 1% /run/shm

$ cat /etc/fstab
# /etc/fstab: static file system information.

# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).

# <file system> <mount point> <type> <options>
<dump> <pass>
proc /proc proc
nodev,noexec,nosuid 0 0
/host/ubuntu/disks/root.disk / ext4
loop,errors=remount-ro 0 1
/host/ubuntu/disks/swap.disk none swap loop,sw
0 0

$ LC_ALL=C sudo fdisk -l /dev/sda
[sudo] password for wearefam:

Disk /dev/sda: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders, total 976773168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0xcb9885ab

Device Boot Start End Blocks Id System
/dev/sda1 * 2048 206847 102400 7 HPFS/NTFS/exFAT
/dev/sda2 206848 931299327 465546240 7 HPFS/NTFS/exFAT
/dev/sda3 931299328 976773119 22736896 27 Hidden NTFS WinRE

$ cat /proc/cmdline
BOOT_IMAGE=/boot/vmlinuz-3.13.0-45-generic root=UUID=001AADA61AAD9964
loop=/ubuntu/disks/root.disk ro