bug#21272: partprobe does not wait for refresh of partition info

On Sun, Aug 16, 2015 at 01:22:15AM +0200, Bjoern Eberth wrote:
> Hi all,
> 
> As the web bugtracker seems to be broken I write this mail.
> 
> I'm using parted 3.2. All this was tested running a Debian jessie release
> within a virtual machine on Windows 8.1 using VMware Workstation 11.
> /dev/sdb is an USB cardreader physically connected to the Windows 8.1
> machine and looped to the virtual machine.
> 
> I was executing a script that does 'partprobe /dev/sdb' and immediatly
> after that 'dd of=/dev/sdb1 if=<something>'. The result is, that I get a
> regular file /dev/sdb1.
> 
> After some more investigation I found, that after executing partprobe the
> partition files got removed and readded to the system.
> So running the script:
> root@debian:~# cat /tmp/test
> partprobe /dev/sdb
> while true; do
>         ls -lad /dev/sdb1
> done

udev is responsible for making sure the device nodes are correct. You
can't depend on them being present without checking for them first. A
udevadm settle after partprobe may also help.

-- 
Brian C. Lane | Anaconda Team | IRC: bcl #anaconda | Port Orchard, WA (PST8PDT)