libvirt users - Feb 2016 - Advice on virtio, or any virtualization solution for hdparm

At the present moment, my guest is running inside qemu and host is kvm
intel, running Ubuntu 14.04, kernel is 4.3.0 stable.   From within the
guest, when I run "hdparm -i /dev/sdb" on the guest, I get:

HDIO_GET_IDENTITY failed: Invalid argument

as the error,but on the host, I will get the full harddisk/SSD info.

Can I know how to resolve this so that the output is the same for both host
and guest?

My strace of hdparm from within the guest (just "-e ioctl" is traced):

ioctl(3, HDIO_GET_MULTCOUNT, 0x618ef0)  = -1 EINVAL (Invalid argument)
ioctl(3, SG_IO, {'S', SG_DXFER_FROM_DEV, cmd[16]=[85, 08, 0e, 00, 00,
00,
01, 00, 00, 00, 00, 00, 00, 40, ec, 00], mx_sb_len=32, iovec_count=0,
dxfer_len=512, timeout=15000, flags=0,
data[512]=["@\0\377?7\310\20\0\0\0\0\0?\0\0\0\0\0\0\0HPAD0409105B"...],
status=00, masked_status=00, sb[0]=[], host_status=0, driver_status=0,
resid=0, duration=184, info=0}) = 0
ioctl(3, HDIO_GET_IDENTITY, 0x7fffda088500) = -1 EINVAL (Invalid argument)
 HDIO_GET_IDENTITY failed: Invalid argument
+++ exited with 22 +++

And at the host level:

ioctl(1, SNDCTL_TMR_TIMEBASE or SNDRV_TIMER_IOCTL_NEXT_DEVICE or TCGETS,
0x7ffd4b096d90) = -1 ENOTTY (Inappropriate ioctl for device)
ioctl(3, HDIO_GET_MULTCOUNT, 0x618ef0)  = -1 ENOTTY (Inappropriate ioctl
for device)
ioctl(3, SG_IO, {'S', SG_DXFER_FROM_DEV, cmd[16]=[85, 08, 0e, 00, 00,
00,
01, 00, 00, 00, 00, 00, 00, 40, ec, 00], mx_sb_len=32, iovec_count=0,
dxfer_len=512, timeout=15000, flags=0,
data[512]=["@\0\377?7\310\20\0\0\0\0\0?\0\0\0\0\0\0\0HPAD0409105B"...],
status=00, masked_status=00, sb[0]=[], host_status=0, driver_status=0,
resid=0, duration=184, info=0}) = 0
ioctl(3, HDIO_GET_IDENTITY, 0x7ffd4b0976e0) = 0
+++ exited with 0 +++

And my qemu command line:

sudo ./x86_64-softmmu/qemu-system-x86_64 -m 1024 -boot c -enable-kvm -net
nic -net user \
-device virtio-scsi-pci \
-drive if=none,file=/dev/sdb,id=sdb,cache=none,format=raw \
-device scsi-block,drive=sdb \
-hda /home/user/ubuntu1404_x86_64/ubuntu1404_x86_64.img

where qemu-system_x86_64 is freshly compiled from latest qemu-devel git
tree.

I would the SSD (internal SATA) at /dev/sdb to be pass directly into qemu.

Please kindly recommend the best solution:   distro (CentOS??),  kernel
version,  qemu command like, and setup procedure for libvirtd?  or
virtio-scsi?
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On 01.02.2016 06:33, Peter Teoh wrote:
> At the present moment, my guest is running inside qemu and host is kvm
> intel, running Ubuntu 14.04, kernel is 4.3.0 stable.   From within the
> guest, when I run "hdparm -i /dev/sdb" on the guest, I get:
> 
> HDIO_GET_IDENTITY failed: Invalid argument
> 
> as the error,but on the host, I will get the full harddisk/SSD info.
> 
> Can I know how to resolve this so that the output is the same for both host
> and guest?
> 
> My strace of hdparm from within the guest (just "-e ioctl" is
traced):
> 
> ioctl(3, HDIO_GET_MULTCOUNT, 0x618ef0)  = -1 EINVAL (Invalid argument)
> ioctl(3, SG_IO, {'S', SG_DXFER_FROM_DEV, cmd[16]=[85, 08, 0e, 00,
00, 00,
> 01, 00, 00, 00, 00, 00, 00, 40, ec, 00], mx_sb_len=32, iovec_count=0,
> dxfer_len=512, timeout=15000, flags=0,
>
data[512]=["@\0\377?7\310\20\0\0\0\0\0?\0\0\0\0\0\0\0HPAD0409105B"...],
> status=00, masked_status=00, sb[0]=[], host_status=0, driver_status=0,
> resid=0, duration=184, info=0}) = 0
> ioctl(3, HDIO_GET_IDENTITY, 0x7fffda088500) = -1 EINVAL (Invalid argument)
>  HDIO_GET_IDENTITY failed: Invalid argument
> +++ exited with 22 +++
> 
I guess this is qemu-kvm limitation. You'd better ask on qemu-devel list.

Michal