Re: [libvirt] [TCK PATCH] block devices: allow specification of size for safety
Dave Allan wrote:
On Wed, May 05, 2010 at 08:54:35PM +0200, Jim Meyering wrote:
> Eric Blake wrote:
> > I was getting failures of domain/103-blockdev-save-restore.t when
> > connecting as qemu:///session, since my uid could stat /dev/sdb
> > but not open it. That test now skips for unprivileged users, as well
> > as adds a layer of sanity checking against expected size to avoid
> > trashing the wrong device.
Can we provide the option to specify the device serial number so that
it's really impossible to trash the wrong device?
Given that this is a good idea, next question is obviously
how to get the serial number. One way seems to be via hdparm,
e.g., hdparm -i /dev/sda
/dev/sda:
Model=ST3320620AS, FwRev=3.AAK, SerialNo=9QF6ET0H
Config={ HardSect NotMFM HdSw>15uSec Fixed DTR>10Mbs RotSpdTol>.5% }
RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=4
BuffType=unknown, BuffSize=16384kB, MaxMultSect=16, MultSect=off
CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=625142448
IORDY=on/off, tPIO={min:120,w/IORDY:120}, tDMA={min:120,rec:120}
PIO modes: pio0 pio1 pio2 pio3 pio4
DMA modes: mdma0 mdma1 mdma2
UDMA modes: udma0 udma1 udma2 udma3 udma4 udma5 *udma6
AdvancedPM=no WriteCache=enabled
Drive conforms to: Unspecified: ATA/ATAPI-1,2,3,4,5,6,7
* signifies the current active mode
which reminds me that some devices have a serial number of all zeros,
so maybe to be truly bullet-proof you'd want all three from that
first line: Model, FwRev, SerialNo