Re: [libvirt] [PATCH 1/3] Revert "storage: For FS pool check for properly formatted target volume"

On 01/12/2017 09:41 AM, Peter Krempa wrote: > On Thu, Jan 12, 2017 at 09:36:01 -0500, John Ferlan wrote: >> >> >> On 01/12/2017 09:24 AM, Peter Krempa wrote: >>> The check does not work properly (crashes) with netfs filesystems and >>> also checking that a device is not empty when attempting to mount a >>> filesystem is not very usefull since the mount will fail anyways. >>> >>> As the code would improve only a very minor corner case I don't really >>> see a reason to have this code at all. >>> >>> This code would also fail if libvirt is compiled without support for >>> blkid and without parted. >>> >>> This reverts commit a11fd69735e6951cda9bf256d8e423696a441aa4. >>> --- >>> src/storage/storage_backend_fs.c | 13 ++----------- >>> 1 file changed, 2 insertions(+), 11 deletions(-) >>> >> >> Instead of reverting why not just fix the issue. > > Because I think the whole check is pointless. It's valid only when > mounting a local filesystem, and in that case basically the same check > is done when mounting the filesystem by the kernel. > Here's the difference between the check and removing the check (not withstanding the no PARTED and no BLKID available)... Create a pool using ext4, start it - life is happy. Destroy the pool. Define a pool using xfs. Start it w/ my change: # virsh pool-start fs error: Failed to start pool fs error: Storage pool already built: Device '/dev/sde' formatted cannot overwrite using 'xfs', requires build --overwrite

w/o my change (e.g. if the change is reverted): # virsh pool-start fs error: Failed to start pool fs error: internal error: Child process (/usr/bin/mount -t xfs /dev/sde /home/vm-images/fs) unexpected exit status 32: mount: wrong fs type, bad option, bad superblock on /dev/sde, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so.