Bug#810582: [partman-base] hangs when reformatting existing fs

[gisl@leonde.de]

Package: partman-base
Version: 188
Severity: important

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I just installed a new stretch system using the alpha 4 netinst image, manual 
install. The root partition that I chose already had a filesystem. When parted 
wanted to create the filesystem, it hung.

I went to another console and saw a process mkfs.ext4 /dev/sda3. I killed the 
process in order to relieve the hanging partman. Curious, as to why the 
mkfs.ext4 hung, I called it manually, and it told me that the partition 
already had a filesystem and asked me whether I really wanted to format it. I 
said yes and let partman do the job again. This time it didn't hang. 

I guess it should run mkfs.ext4 in non-interactive "yes, really do it and 
don't ask me any questions" mode or something like that.

Thanks.