Note: This bug is displayed in read-only format because the product is no longer active in Red Hat Bugzilla.

RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Bug 1039501

Summary:	[provisioning] discard=on broken
Product:	Red Hat Enterprise Linux 7	Reporter:	Sibiao Luo <sluo>
Component:	qemu-kvm	Assignee:	Paolo Bonzini <pbonzini>
Status:	CLOSED CURRENTRELEASE	QA Contact:	Virtualization Bugs <virt-bugs>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	7.0	CC:	acathrow, areis, chayang, hhuang, huding, juzhang, michen, pbonzini, qzhang, virt-maint, xfu
Target Milestone:	rc
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:	qemu-kvm-1.5.3-22.el7	Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2014-06-13 12:09:35 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Sibiao Luo 2013-12-09 09:49:59 UTC

Description of problem:
when i do provisioning test for ide/ahci interface with discard=on under UNMAP mode, but it fail to discard the free space after remove the data in guest.
Also tried the scsi-hd/scsi-block did not hit such issue.

Version-Release number of selected component (if applicable):
host info:
3.10.0-60.el7.x86_64
qemu-kvm-rhev-1.5.3-21.el7.x86_64
seabios-1.7.2.2-4.el7.x86_64
guest info:
3.10.0-60.el7.x86_64

How reproducible:
100%

Steps to Reproduce:
1.generate a scsi disk with scsi_debug using UNMAP mode.
# modprobe scsi_debug dev_size_mb=1024 lbpu=1
# lsscsi
[0:0:0:0]    disk    ATA      ST3500413AS      HP64  /dev/sda 
[2:0:0:0]    cd/dvd  hp       DVD-RAM GH80N    RF01  /dev/sr0 
[6:0:0:0]    disk    EQLOGIC  100E-00          5.0   /dev/sdb 
[9:0:0:0]    disk    Linux    scsi_debug       0004  /dev/sdc 
# cat /sys/block/sdc/device/scsi_disk/9\:0\:0\:0/provisioning_mode
unmap
# cat /sys/bus/pseudo/drivers/scsi_debug/map
                <----------nothing output
2.boot a guest with /dev/sdc as a ide/ahci data disk, like:
# /usr/libexec/qemu-kvm -M pc -S -cpu SandyBridge -enable-kvm...-drive file=/dev/sdc,if=none,id=drive-data-disk,cache=none,format=raw,aio=native,discard=on -device ide-hd,drive=drive-data-disk,id=data-disk

3.Make file system (both xfs and ext4 hit it) to the disk in the guest.
# mkfs.xfs /dev/sdb
meta-data=/dev/sdb               isize=256    agcount=4, agsize=65536 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=0
data     =                       bsize=4096   blocks=262144, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0
log      =internal log           bsize=4096   blocks=12800, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0

4.On the host.
# cat /sys/bus/pseudo/drivers/scsi_debug/map

5.in the guest
# mount /dev/sdb /home/test
# dd if=/dev/zero of=/home/test/file
dd: writing to ‘/home/test/file’: No space left on device
1928857+0 records in
1928856+0 records out
987574272 bytes (988 MB) copied, 2.05315 s, 481 MB/s

6.cat map in host.
# cat /sys/bus/pseudo/drivers/scsi_debug/map

7.in guest.
# rm -f /home/test/file
# fstrim /home/test

8.cat map in host.
# cat /sys/bus/pseudo/drivers/scsi_debug/map

Actual results:
after step 4,
# cat /sys/bus/pseudo/drivers/scsi_debug/map
0-255,524288-524291,524296-524319,1048576-1048579,1048584-1151007,1572864-1572867,1572872-1572895,2096896-2097151
after step 6,
# cat /sys/bus/pseudo/drivers/scsi_debug/map
0-524279,524288-524291,524296-524319,524352-1048567,1048576-1048579,1048584-1151007,1151040-1539975,1572864-1572867,1572872-1572895,1572928-2064447,2096896-2097151
after step 8, the cat map output did not change. 
# cat /sys/bus/pseudo/drivers/scsi_debug/map
0-524279,524288-524291,524296-524319,524352-1048567,1048576-1048579,1048584-1151007,1151040-1539975,1572864-1572867,1572872-1572895,1572928-2064447,2096896-2097151

Expected results:
discard the free space successfully after remove the data in guest. like the scsi-hd test results:
after step 4,
# cat /sys/bus/pseudo/drivers/scsi_debug/map
0-535,544-567,576-623,648-655,776-33551,262144-262159,786432-786447,1048576-1114111,1310720-1310735,1835008-1835023,2097024-2097151
after step 6,
# cat /sys/bus/pseudo/drivers/scsi_debug/map
0-535,544-567,576-623,648-655,776-246543,262144-262159,278528-786447,786952-1310735,1311240-1311759,1327104-1835023,1835528-1837751,1851392-2097151
after step 8,
# cat /sys/bus/pseudo/drivers/scsi_debug/map
0-623,648-655,776-246543,262144-262159,278528-786447,786952-1310735,1311240-1311759,1327104-1835023,1835528-1837751,1851392-2097151

Additional info:
# /usr/libexec/qemu-kvm -M pc -S -cpu SandyBridge -enable-kvm -m 2048 -smp 2,sockets=2,cores=1,threads=1 -no-kvm-pit-reinjection -usb -device usb-tablet,id=input0 -name sluo -uuid 990ea161-6b67-47b2-b803-19fb01d30d30 -rtc base=localtime,clock=host,driftfix=slew -device virtio-serial-pci,id=virtio-serial0,max_ports=16,vectors=0,bus=pci.0,addr=0x3 -chardev socket,id=channel1,path=/tmp/helloworld1,server,nowait -device virtserialport,chardev=channel1,name=com.redhat.rhevm.vdsm,bus=virtio-serial0.0,id=port1 -chardev socket,id=channel2,path=/tmp/helloworld2,server,nowait -device virtserialport,chardev=channel2,name=com.redhat.rhevm.vdsm,bus=virtio-serial0.0,id=port2 -drive file=iscsi://10.66.90.100:3260/iqn.2001-05.com.equallogic:0-8a0906-4c41f7d03-453f49b421052a57-s2-sluo-270305-1/0,if=none,id=drive-system-disk,cache=none,format=raw,aio=native,werror=stop,rerror=stop -iscsi id=iqn0 -device virtio-scsi-pci,id=scsi0,bus=pci.0,addr=0x4 -device scsi-block,drive=drive-system-disk,bus=scsi0.0,id=libiscsi-system-disk,bootindex=1 -netdev tap,id=hostnet0,vhost=on,script=/etc/qemu-ifup -device rtl8139,netdev=hostnet0,id=rtl8139-net-pci0,mac=00:01:02:B6:40:21,bus=pci.0,addr=0x5 -device virtio-balloon-pci,id=ballooning,bus=pci.0,addr=0x6 -global PIIX4_PM.disable_s3=0 -global PIIX4_PM.disable_s4=0 -drive file=/dev/sdc,if=none,id=drive-data-disk,cache=none,format=raw,aio=native,discard=on -device ide-hd,drive=drive-data-disk,id=data-disk -k en-us -boot menu=on -qmp tcp:0:4444,server,nowait -serial unix:/tmp/ttyS0,server,nowait -vnc :1 -spice disable-ticketing,port=5931 -monitor stdio

Comment 1 Sibiao Luo 2013-12-10 05:24:18 UTC

(In reply to Sibiao Luo from comment #0)
> Expected results:
> discard the free space successfully after remove the data in guest. like the
> scsi-hd test results:
> after step 4,
> # cat /sys/bus/pseudo/drivers/scsi_debug/map
> 0-535,544-567,576-623,648-655,776-33551,262144-262159,786432-786447,1048576-
> 1114111,1310720-1310735,1835008-1835023,2097024-2097151
> after step 6,
> # cat /sys/bus/pseudo/drivers/scsi_debug/map
> 0-535,544-567,576-623,648-655,776-246543,262144-262159,278528-786447,786952-
> 1310735,1311240-1311759,1327104-1835023,1835528-1837751,1851392-2097151
> after step 8,
> # cat /sys/bus/pseudo/drivers/scsi_debug/map
> 0-623,648-655,776-246543,262144-262159,278528-786447,786952-1310735,1311240-
> 1311759,1327104-1835023,1835528-1837751,1851392-2097151
> 
Sorry, above is the virtio-blk interface testing results which should not support discard, and the scsi-hd interface also hit the same issue, i will separate a new bug for it.

The expected results should like the scsi-block interface with discard=on,like:
e.g:...-drive file=/dev/sdc,if=none,id=drive-data-disk,cache=none,format=raw,aio=native,werror=stop,rerror=stop,discard=on -device virtio-scsi-pci,id=scsi1,bus=pci.0,addr=0x7 -device scsi-block,drive=drive-data-disk,bus=scsi1.0,id=data-disk

after step 4,
# cat /sys/bus/pseudo/drivers/scsi_debug/map
0-255,262144-262147,262152-262175,524288-524291,524296-524319,786432-786435,786440-786463,1048576-1048579,1048584-1151007,1310720-1310723,1310728-1310751,1572864-1572867,1572872-1572895,1835008-1835011,1835016-1835039,2096896-2097151
after step 6,
# cat /sys/bus/pseudo/drivers/scsi_debug/map
0-262135,262144-262147,262152-262175,262208-524279,524288-524291,524296-524319,524352-786423,786432-786435,786440-786463,786496-1048567,1048576-1048579,1048584-1151007,1151040-1310479,1310720-1310723,1310728-1310751,1310784-1572855,1572864-1572867,1572872-1572895,1572928-1769607,1769616-1834991,1835008-1835011,1835016-1835039,1835072-2031839,2096896-2097151
after step 8,
# cat /sys/bus/pseudo/drivers/scsi_debug/map
0-95,262144-262147,262152-262175,524288-524291,524296-524319,786432-786435,786440-786463,1048576-1048579,1048584-1151007,1310720-1310723,1310728-1310751,1572864-1572867,1572872-1572895,1835008-1835011,1835016-1835039

Best Regards,
sluo

Comment 2 Paolo Bonzini 2013-12-10 13:47:44 UTC

*** Bug 1039823 has been marked as a duplicate of this bug. ***

Comment 3 Paolo Bonzini 2013-12-10 13:50:12 UTC

Fixed by upstream commit 8b7a5415f9297c1fbae5bff28dcb059d50c1b045.

Comment 8 huiqingding 2013-12-23 05:29:03 UTC

Reproduce this bug using the following version:
host info:
3.10.0-63.el7.x86_64
qemu-kvm-rhev-1.5.3-21.el7.x86_64
seabios-bin-1.7.2.2-4.el7.noarch
guest info:
3.10.0-54.0.1.el7.x86_64

Steps to Reproduce:
1.generate a scsi disk with scsi_debug using UNMAP mode.
# modprobe scsi_debug dev_size_mb=1024 lbpu=1
# lsscsi
[0:0:0:0]    disk    ATA      ST500DM002-1BD14 HP73  /dev/sda 
[2:0:0:0]    cd/dvd  hp       DVD-RAM GH82N    R203  /dev/sr0 
[6:0:0:0]    storage IET      Controller       0001  -        
[6:0:0:1]    disk    IET      VIRTUAL-DISK     0001  /dev/sdc 
[6:0:0:2]    disk    IET      VIRTUAL-DISK     0001  /dev/sdd 
[6:0:0:3]    disk    IET      VIRTUAL-DISK     0001  /dev/sde 
[6:0:0:4]    disk    IET      VIRTUAL-DISK     0001  /dev/sdf 
[7:0:0:0]    storage IET      Controller       0001  -        
[7:0:0:1]    disk    IET      VIRTUAL-DISK     0001  /dev/sdb 
[8:0:0:0]    disk    Linux    scsi_debug       0004  /dev/sdg 
# cat /sys/block/sdg/device/scsi_disk/8\:0\:0\:0/provisioning_mode 
unmap
# cat /sys/bus/pseudo/drivers/scsi_debug/map
                <----------nothing output
2.boot a guest with /dev/sdg as a ide/ahci data disk, like:
# /usr/libexec/qemu-kvm -S -M pc-i440fx-rhel7.0.0 -cpu SandyBridge -enable-kvm -m 4G -smp 4,sockets=2,cores=2,threads=1 -name rhel7 -uuid 355a2475-4e03-4cdd-bf7b-5d6a59edaa61 -rtc base=localtime,clock=host,driftfix=slew -drive file=/home/RHEL-7.0-20131127.1.qcow2_v3-bak,if=none,id=drive-system-disk,cache=writeback -iscsi id=iqn,initiator-name=iqn.1994-05.com.redhat:sluo, -device virtio-scsi-pci,bus=pci.0,addr=0x5,id=scsi0,ioeventfd=off -device virtio-balloon-pci,id=ballooning -global PIIX4_PM.disable_s3=0 -global PIIX4_PM.disable_s4=0 -netdev tap,id=tap1,vhost=on,queues=4,script=/etc/ovs-ifup,downscript=/etc/ovs-ifdown -device rtl8139,netdev=tap1,id=nic1,mac=1a:59:0a:4b:5a:94 -k en-us -boot menu=on,reboot-timeout=-1,strict=on -qmp tcp:0:4445,server,nowait -serial unix:/tmp/ttyS0,server,nowait -vnc :3 -spice port=5932,disable-ticketing -vga qxl -monitor stdio -monitor tcp:0:7445,server,nowait -monitor unix:/tmp/monitor1,server,nowait -drive file=/dev/sdg,if=none,id=drive-data-disk,cache=none,format=raw,aio=native,discard=on -device ide-hd,drive=drive-data-disk,id=data-disk

3.Make file system (both xfs and ext4 hit it) to the disk in the guest.
# mkfs.xfs /dev/sdb
meta-data=/dev/sdb               isize=256    agcount=4, agsize=65536 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=0
data     =                       bsize=4096   blocks=262144, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0
log      =internal log           bsize=4096   blocks=12800, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0

4.On the host.
# cat /sys/bus/pseudo/drivers/scsi_debug/map

5.in the guest
# mount /dev/sdb /home/test
# dd if=/dev/zero of=/home/test/file
dd: writing to ‘/home/test/file’: No space left on device
1928857+0 records in
1928856+0 records out
987574272 bytes (988 MB) copied, 2.05315 s, 481 MB/s

6.cat map in host.
# cat /sys/bus/pseudo/drivers/scsi_debug/map

7.in guest.
# rm -f /home/test/file
# fstrim /home/test

8.cat map in host.
# cat /sys/bus/pseudo/drivers/scsi_debug/map

Actual results:
after step 4,
# cat /sys/bus/pseudo/drivers/scsi_debug/map
0-391,524288-524291,524296-524319,1048576-1048579,1048584-1151007,1572864-1572867,1572872-1572895,2096896-2097151
after step 6,
# cat /sys/bus/pseudo/drivers/scsi_debug/map
0-524279,524288-524291,524296-524319,524352-1048567,1048576-1048579,1048584-1151007,1151040-1507287,1572864-1572867,1572872-1572895,1572928-2097151
after step 8, the cat map output did not change. 
# cat /sys/bus/pseudo/drivers/scsi_debug/map
0-524279,524288-524291,524296-524319,524352-1048567,1048576-1048579,1048584-1151007,1151040-1507287,1572864-1572867,1572872-1572895,1572928-2097151
Additional info:
I also test scsi-hd interface using the above steps, also hit this bug.

Verify this bug using the following version:
host info:
3.10.0-63.el7.x86_64
qemu-kvm-1.5.3-30.el7.x86_64
seabios-bin-1.7.2.2-4.el7.noarch
guest info:
3.10.0-54.0.1.el7.x86_64

Steps to Reproduce:
1.generate a scsi disk with scsi_debug using UNMAP mode.
# modprobe scsi_debug dev_size_mb=1024 lbpu=1
# lsscsi
[0:0:0:0]    disk    ATA      ST500DM002-1BD14 HP73  /dev/sda 
[2:0:0:0]    cd/dvd  hp       DVD-RAM GH82N    R203  /dev/sr0 
[6:0:0:0]    storage IET      Controller       0001  -        
[6:0:0:1]    disk    IET      VIRTUAL-DISK     0001  /dev/sdc 
[6:0:0:2]    disk    IET      VIRTUAL-DISK     0001  /dev/sdd 
[6:0:0:3]    disk    IET      VIRTUAL-DISK     0001  /dev/sde 
[6:0:0:4]    disk    IET      VIRTUAL-DISK     0001  /dev/sdf 
[7:0:0:0]    storage IET      Controller       0001  -        
[7:0:0:1]    disk    IET      VIRTUAL-DISK     0001  /dev/sdb 
[8:0:0:0]    disk    Linux    scsi_debug       0004  /dev/sdg 
# cat /sys/block/sdg/device/scsi_disk/8\:0\:0\:0/provisioning_mode 
unmap
# cat /sys/bus/pseudo/drivers/scsi_debug/map
                <----------nothing output
2.boot a guest with /dev/sdg as a ide/ahci data disk, like:
# /usr/libexec/qemu-kvm -S -M pc-i440fx-rhel7.0.0 -cpu SandyBridge -enable-kvm -m 4G -smp 4,sockets=2,cores=2,threads=1 -name rhel7 -uuid 355a2475-4e03-4cdd-bf7b-5d6a59edaa61 -rtc base=localtime,clock=host,driftfix=slew -drive file=/home/RHEL-7.0-20131127.1.qcow2_v3-bak,if=none,id=drive-system-disk,cache=writeback -iscsi id=iqn,initiator-name=iqn.1994-05.com.redhat:sluo, -device virtio-scsi-pci,bus=pci.0,addr=0x5,id=scsi0,ioeventfd=off -device virtio-balloon-pci,id=ballooning -global PIIX4_PM.disable_s3=0 -global PIIX4_PM.disable_s4=0 -netdev tap,id=tap1,vhost=on,queues=4,script=/etc/ovs-ifup,downscript=/etc/ovs-ifdown -device rtl8139,netdev=tap1,id=nic1,mac=1a:59:0a:4b:5a:94 -k en-us -boot menu=on,reboot-timeout=-1,strict=on -qmp tcp:0:4445,server,nowait -serial unix:/tmp/ttyS0,server,nowait -vnc :3 -spice port=5932,disable-ticketing -vga qxl -monitor stdio -monitor tcp:0:7445,server,nowait -monitor unix:/tmp/monitor1,server,nowait -drive file=/dev/sdg,if=none,id=drive-data-disk,cache=none,format=raw,aio=native,discard=on -device ide-hd,drive=drive-data-disk,id=data-disk

3.Make file system (both xfs and ext4 hit it) to the disk in the guest.
# mkfs.xfs /dev/sdb
meta-data=/dev/sdb               isize=256    agcount=4, agsize=65536 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=0
data     =                       bsize=4096   blocks=262144, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0
log      =internal log           bsize=4096   blocks=12800, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0

4.On the host.
# cat /sys/bus/pseudo/drivers/scsi_debug/map

5.in the guest
# mount /dev/sdb /home/test
# dd if=/dev/zero of=/home/test/file
dd: writing to ‘/home/test/file’: No space left on device
1928857+0 records in
1928856+0 records out
987574272 bytes (988 MB) copied, 2.05315 s, 481 MB/s

6.cat map in host.
# cat /sys/bus/pseudo/drivers/scsi_debug/map

7.in guest.
# rm -f /home/test/file
# fstrim /home/test

8.cat map in host.
# cat /sys/bus/pseudo/drivers/scsi_debug/map

after step 4,
# cat /sys/bus/pseudo/drivers/scsi_debug/map
0-255,524288-524291,524296-524319,1048576-1048579,1048584-1151007,1572864-1572867,1572872-1572895,2096896-2097151
after step 6,
# cat /sys/bus/pseudo/drivers/scsi_debug/map
0-524279,524288-524291,524296-524319,524352-1048567,1048576-1048579,1048584-1151007,1151040-1507287,1572864-1572867,1572872-1572895,1572928-2097151
after step 8, discard the free space successfully after remove the data in guest
# cat /sys/bus/pseudo/drivers/scsi_debug/map
0-95,524288-524291,524296-524319,1048576-1048579,1048584-1151007,1572864-1572867,1572872-1572895

Additional info:
I also test scsi-hd interface using the above steps, the result is same as the above: after step 8, discard the free space successfully after remove the data in guest

Based on the above result, I think this bug is fixed.

Comment 10 Ludek Smid 2014-06-13 12:09:35 UTC

This request was resolved in Red Hat Enterprise Linux 7.0.

Contact your manager or support representative in case you have further questions about the request.