Hi All,
I use libvirtd to call qemu drive_mirror return error message "Operation not permitted", But directly run qemu and call drive_mirror is OK;
when drive_mirror target is logic device return error message "Operation not permitted",But the file is OK;
Operating Environment：
OS:ubuntu 14.04
kernel:3.16.0-28-generic
libvirt-bin version: 1.2.2-0ubuntu13.1.17
qemu:2.5.0 or 2.6.0
run vm user: root
（retry in redhat7.2 have the same problem！）
Here is my running process:
libvirtd call
prepare libvirt xml libvirt.xml
<?xml version="1.0"?><domain type="kvm">
<name>i-745F35DC</name>
<memory>65536</memory>
<vcpu>1</vcpu>
<cpu mode="host-model"><model fallback="allow"/><topology sockets="1" threads="1" cores="1"/></cpu>
<os><type>hvm</type><boot dev="cdrom"/><boot dev="hd"/></os>
<features><acpi/><apic/><pae/></features>
<on_poweroff>destroy</on_poweroff>
<on_reboot>restart</on_reboot>
<on_crash>destroy</on_crash>
<devices>
<emulator>/usr/local/qemu-2.5.0-20160720/bin/qemu-system-x86_64</emulator>
<graphics type="vnc" passwd="" autoport="yes" keymap="en-us" listen="0.0.0.0"/>
<disk type="file" device="disk">
<driver name="qemu" type="raw" cache="none"/>
<source file="/tmp/image.raw"/>
<target dev="hda" bus="ide"/>
<serial>bc-system</serial>
</disk>
</devices>
<clock offset="localtime"/>
</domain>
virsh create libvirt.xml
address@hidden:/opt/run/instance/i-745F35DC# virsh list
Id Name State
----------------------------------------------------
2 i-745F35DC running
call drive_mirror:
virsh qemu-monitor-command --hmp i-745F35DC 'drive_mirror -n -f drive-ide0-0-0 /dev/vg_bc_local/test raw'
Could not open '/dev/vg_bc_local/test': Operation not permitted
directly run qemu and call drive_mirror:
/usr/local/qemu-2.5.0-20160720/bin/qemu-system-x86_64 -hda /tmp/image.raw -m 64 --enable-kvm -vnc :51 -monitor stdio
QEMU 2.5.0 monitor - type 'help' for more information
(qemu) info block
ide0-hd0 (#block135): /tmp/image.raw (raw)
Cache mode: writeback
(qemu) drive_mirror -n -f ide0-hd0 /dev/vg_bc_local/test raw
(qemu) info block-jobs
Type mirror, device ide0-hd0: Completed 41126400 of 41126400 bytes, speed limit 0 bytes/s
(qemu) block_job_cancel ide0-hd0
(qemu) info block-jobs
No active jobs
It is OK!!!
Here is my debugging process:
Recompile qemu-2.5.0 to enable debug
../configure --prefix=/usr/local/qemu-2.5.0-20160720 --enable-trace-backend=simple --enable-werror --disable-xen --disable-virtfs --enable-kvm --enable-seccomp --enable-docs --enable-debug-tcg --enable-vnc-sasl --enable-linux-aio --enable-lzo --enable-snappy --enable-usb-redir --enable-vnc-png --disable-vnc-jpeg --enable-uuid --disable-vhost-scsi --enable-rbd --block-drv-rw-whitelist=qcow2,raw,file,host_device,blkdebug,nbd,iscsi,rbd,cdp --block-drv-ro-whitelist=vmdk,vhdx,vpc --target-list=x86_64-softmmu CFLAGS=-O0
Use libvirtd to Re-run VM and debug by gdb
VM process info:
root 7804 1 0 10:45 ? 00:00:10 /usr/local/qemu-2.5.0-20160720/bin/qemu-system-x86_64 -name i-745F35DC -S -machine pc-i440fx-2.5,accel=kvm,usb=off -cpu Westmere,+invpcid,+erms,+bmi2,+smep,+avx2,+bmi1,+fsgsbase,+abm,+rdtscp,+pdpe1gb,+rdrand,+f16c,+avx,+osxsave,+xsave,+tsc-deadline,+movbe,+pcid,+pdcm,+xtpr,+fma,+tm2,+est,+vmx,+ds_cpl,+monitor,+dtes64,+pclmuldq,+pbe,+tm,+ht,+ss,+acpi,+ds,+vme -m 64 -realtime mlock=off -smp 1,sockets=1,cores=1,threads=1 -uuid ef55dfa6-b82e-488d-a7fc-4c882f8091ab -no-user-config -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/i-745F35DC.monitor,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=localtime -no-shutdown -boot strict=on -device piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2 -drive file=/tmp/image.raw,if=none,id=drive-ide0-0-0,format=raw,serial=bc-system,cache=none -device ide-hd,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0,bootindex=2 -vnc 0.0.0.0:0,password -k en-us -device cirrus-vga,id=video0,bus=pci.0,addr=0x2 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3
gdb -p 7804
set breakpoint
(gdb) i b
Num Type Disp Enb Address What
1 breakpoint keep y 0x00007f51d9e92cb1 in qmp_drive_mirror at /opt/qemu/qemu-2.5.0/blockdev.c:3310
2 breakpoint keep y 0x00007f51da1252f2 in raw_open_common at /opt/qemu/qemu-2.5.0/block/raw-posix.c:457
3 breakpoint keep y 0x00007f51da12500f in raw_parse_flags at /opt/qemu/qemu-2.5.0/block/raw-posix.c:358
(gdb)
call drive_mirror and debug:
(gdb)
raw_open_common (bs=0x7f4b27259ab0, options=0x7f4b27480290, bdrv_flags=24674, open_flags=0, errp=0x7fff4a19f548)
at /opt/qemu/qemu-2.5.0/block/raw-posix.c:484
484 s->fd = -1;
(gdb) n
485 fd = qemu_open(filename, s->open_flags, 0644);
(gdb) s
qemu_open (name=0x7f4b2642b5c0 "/dev/vg_bc_local/test", flags=2) at /opt/qemu/qemu-2.5.0/util/osdep.c:177
177 int mode = 0;
(gdb) n
183 if (strstart(name, "/dev/fdset/", &fdset_id_str)) {
(gdb)
214 if (flags & O_CREAT) {
(gdb)
223 char arg[1000] = {0};
(gdb)
227 ret = open(name, flags , mode);
(gdb) p name
$1 = 0x7f4b2642b5c0 "/dev/vg_bc_local/test"
(gdb) p flags
$2 = 2
(gdb) p mode
$3 = 0
(gdb) n
(gdb) p ret
$4 = -1
get system erroron is :Operation not permitted
!!!!!!!!!!!!!!
Re-run VM Directly and debug by gdb
/usr/local/qemu-2.5.0-20160720/bin/qemu-system-x86_64 -hda /tmp/image.raw -m 64 --enable-kvm -vnc :51 -monitor stdio
(qemu) info block
ide0-hd0 (#block135): /tmp/image.raw (raw)
Cache mode: writeback
(qemu) drive_mirror -n -f ide0-hd0 /dev/vg_bc_local/test raw
gdb debug:
(gdb) i b
Num Type Disp Enb Address What
1 breakpoint keep y 0x00007f51d9e92cb1 in qmp_drive_mirror at /opt/qemu/qemu-2.5.0/blockdev.c:3310
2 breakpoint keep y 0x00007f51da1252f2 in raw_open_common at /opt/qemu/qemu-2.5.0/block/raw-posix.c:457
3 breakpoint keep y 0x00007f51da12500f in raw_parse_flags at /opt/qemu/qemu-2.5.0/block/raw-posix.c:358
(gdb)
raw_open_common (bs=0x7f51dc15d350, options=0x7f51dc083110, bdrv_flags=24642, open_flags=0, errp=0x7fff5aaa9738)
at /opt/qemu/qemu-2.5.0/block/raw-posix.c:484
484 s->fd = -1;
(gdb) n
485 fd = qemu_open(filename, s->open_flags, 0644);
(gdb) s
qemu_open (name=0x7f51dca09230 "/dev/vg_bc_local/test", flags=2) at /opt/qemu/qemu-2.5.0/util/osdep.c:177
177 int mode = 0;
(gdb) n
183 if (strstart(name, "/dev/fdset/", &fdset_id_str)) {
(gdb)
214 if (flags & O_CREAT) {
(gdb)
223 char arg[1000] = {0};
(gdb)
227 ret = open(name, flags , mode);
(gdb) p name
$1 = 0x7f51dca09230 "/dev/vg_bc_local/test"
(gdb) p flags
$2 = 2
(gdb) p mode
$3 = 0
(gdb) n
(gdb) p ret
$4 = 16
(gdb)
It is OK!!!!
Why ？？？