Hello RMs, Hello SRMs, Hello D-I folks,
i dare to write on this channels because there is a IMHO rather serious bug in os-prober which up to now went below the radar of everyone it seems. So this email in the first place is ment to make more people aware of this issue and here is hope that someone will catch this up and fix it. os-prober corrupts partitions https://bugs.debian.org/788062 This bug leads to serious data loss and is TTBOMK also present in stable. The original bugreport talks about LVM partitions being corrupted but to my observations also simple partition layouts with extented partitions are being hosed. Attached you will find a matching snippet from syslog where sda4 is a extended partition. Note the line where is says: >>>WARNING<<< Wrong ufstype may corrupt your filesystem IIRC i saw other messages where it talked s.th. about not valid QNX4 format. On upgrading one machine jessie -> stretch grub asked me to choose the partition to install so, because it said the ID/number of original partition would have changed. To sum it up: This one is set _valid_ to highest bug priority debian knows. Side note: Here i want to make crystal clear i do not blame maintainers or any other debian folks. I am just saying there i a rather unfortunate situation which i hope will now be handled. Thanks for your time. kind regards, Thilo
Mar 12 06:56:39 tosh os-prober: debug: running /usr/lib/os-probes/50mounted-tests on /dev/sda4 Mar 12 06:56:39 tosh kernel: [ 1919.296306] EXT4-fs (sda4): unable to read superblock Mar 12 06:56:39 tosh kernel: [ 1919.299097] EXT4-fs (sda4): unable to read superblock Mar 12 06:56:39 tosh kernel: [ 1919.302061] EXT4-fs (sda4): unable to read superblock Mar 12 06:56:39 tosh kernel: [ 1919.311096] XFS (sda4): Invalid superblock magic number Mar 12 06:56:39 tosh kernel: [ 1919.319151] FAT-fs (sda4): utf8 is not a recommended IO charset for FAT filesystems, filesystem will be case sensitive! Mar 12 06:56:39 tosh kernel: [ 1919.319345] FAT-fs (sda4): bogus number of reserved sectors Mar 12 06:56:39 tosh kernel: [ 1919.320495] FAT-fs (sda4): Can't find a valid FAT filesystem Mar 12 06:56:39 tosh kernel: [ 1919.323291] FAT-fs (sda4): utf8 is not a recommended IO charset for FAT filesystems, filesystem will be case sensitive! Mar 12 06:56:39 tosh kernel: [ 1919.323478] FAT-fs (sda4): bogus number of reserved sectors Mar 12 06:56:39 tosh kernel: [ 1919.324698] FAT-fs (sda4): Can't find a valid FAT filesystem Mar 12 06:56:39 tosh kernel: [ 1919.334709] MINIX-fs: unable to read superblock Mar 12 06:56:39 tosh kernel: [ 1919.340084] attempt to access beyond end of device Mar 12 06:56:39 tosh kernel: [ 1919.340093] sda4: rw=16, want=3, limit=2 Mar 12 06:56:39 tosh kernel: [ 1919.340098] hfsplus: unable to find HFS+ superblock Mar 12 06:56:39 tosh kernel: [ 1919.343453] qnx4: no qnx4 filesystem (no root dir). Mar 12 06:56:39 tosh kernel: [ 1919.347670] You didn't specify the type of your ufs filesystem Mar 12 06:56:39 tosh kernel: [ 1919.347670] Mar 12 06:56:39 tosh kernel: [ 1919.347670] mount -t ufs -o ufstype=sun|sunx86|44bsd|ufs2|5xbsd|old|hp|nextstep|nextstep-cd|openstep ... Mar 12 06:56:39 tosh kernel: [ 1919.347670] Mar 12 06:56:39 tosh kernel: [ 1919.347670] >>>WARNING<<< Wrong ufstype may corrupt your filesystem, default is ufstype=old Mar 12 06:56:39 tosh kernel: [ 1919.353385] hfs: can't find a HFS filesystem on dev sda4 root ~ # fdisk -l /dev/sda Disk /dev/sda: 238,5 GiB, 256060514304 bytes, 500118192 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0x14e852ea Device Boot Start End Sectors Size Id Type /dev/sda1 * 2048 31250431 31248384 14,9G 83 Linux /dev/sda2 31250432 56641535 25391104 12,1G 83 Linux /dev/sda3 56641536 97656831 41015296 19,6G 82 Linux swap / Solaris /dev/sda4 97658878 500117503 402458626 191,9G 5 Extended /dev/sda5 97658880 500117503 402458624 191,9G 83 Linux