Linux 4.4.0: wrong value for /sys/*/queue/discard_granularity
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Fedora) |
Fix Released
|
Undecided
|
|||
linux (Ubuntu) |
Triaged
|
Medium
|
Unassigned |
Bug Description
With kernel 4.4.0-21.37 in xenial and yakkety, the value of queue/discard_
$ cat /sys/devices/
1
$
This is at odds with the values on ramdisks:
$ cat /sys/devices/
4096
$
And with lvm2 2.02.150-1ubuntu1, currently in yakkety-proposed, this always results in an error message from lvremove if discard is configured, and discard is not actually used; e.g., from my schroot output:
E: 05lvm: WARNING: Device /dev/sda7: queue/discard_
This bug has also been reported against Linux 4.4 in Fedora.
https:/
ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: linux-image-
ProcVersionSign
Uname: Linux 4.4.0-21-generic x86_64
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/
/dev/snd/pcmC0D0p: vorlon 3681 F...m pulseaudio
/dev/snd/
CurrentDesktop: Unity
Date: Thu Apr 28 16:39:54 2016
HibernationDevice: RESUME=
InstallationDate: Installed on 2010-09-24 (2043 days ago)
InstallationMedia: Ubuntu 10.04.1 LTS "Lucid Lynx" - Release amd64 (20100816.1)
MachineType: LENOVO 2306CTO
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=
RelatedPackageV
linux-
linux-
linux-firmware 1.157
SourcePackage: linux
UpgradeStatus: Upgraded to xenial on 2016-04-15 (13 days ago)
dmi.bios.date: 10/25/2013
dmi.bios.vendor: LENOVO
dmi.bios.version: G2ET97WW (2.57 )
dmi.board.
dmi.board.name: 2306CTO
dmi.board.vendor: LENOVO
dmi.board.version: Not Defined
dmi.chassis.
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.
dmi.modalias: dmi:bvnLENOVO:
dmi.product.name: 2306CTO
dmi.product.
dmi.sys.vendor: LENOVO
Changed in linux (Ubuntu): | |
importance: | Undecided → Medium |
tags: | added: kernel-da-key |
Changed in linux (Ubuntu): | |
status: | Confirmed → Triaged |
Changed in linux (Fedora): | |
importance: | Unknown → Undecided |
status: | Unknown → Fix Released |
Description of problem:
See bug 1313377
Instead of reporting 4096, the kernel reports 1 for block/8: 0/queue/ discard_ granularity
cat /sys/dev/
Version-Release number of selected component (if applicable): fc23.x86_ 64 fc23.x86_ 64
4.4.2-301.
4.4.3-300.
Not affected: 4.3.5-300. fc23.x86_ 64
Additional info:
This makes lvremove not discard logical volumes, since it assumes that the granularity is always bigger or equal to 512 for devices supporting discard/trim.