On 3/5/18 10:17 PM, Randy Dunlap wrote: > Hi, > > With the following kernel config entries on Linux 4.16-rc3: > > CONFIG_EXT2_FS=m > # CONFIG_EXT2_FS_XATTR is not set > CONFIG_EXT3_FS=m > # CONFIG_EXT3_FS_POSIX_ACL is not set > # CONFIG_EXT3_FS_SECURITY is not set > CONFIG_EXT4_FS=y > CONFIG_EXT4_FS_POSIX_ACL=y > CONFIG_EXT4_FS_SECURITY=y > # CONFIG_EXT4_ENCRYPTION is not set > # CONFIG_EXT4_DEBUG is not set > CONFIG_JBD2=y > # CONFIG_JBD2_DEBUG is not set > > ext4_fill_super() tells me: > > [ 3.033174] EXT4-fs (sda5): couldn't mount as ext3 due to feature incompatibilities > [ 3.100186] EXT4-fs (sda5): mounted filesystem with ordered data mode. Opts: (null) > [ 3.102683] VFS: Mounted root (ext4 filesystem) readonly on device 8:5. > > > This is a new install, new filesystem. It has never been ext2 or ext3. > > After bootup and before I do anything else, I can remount /dev/sda5 on / as > rw and everything is OK. > > What am I doing wrong? Hm you're the second person to report this in a week. (see EXT4-fs (mmcblk0p1): couldn't mount as ext3 due to feature incompatibilities) It sounds like filesystem probing behavior; it tried to mount as ext3 and failed (as it should fail) then moved on to ext4 and succeeded. I sent: [PATCH V2] ext4: don't complain about incorrect features when probing which should fix it, but I really wonder why this is just now showing up for people; it could be a combination of /etc/filesystems, fstab entries, blkid handling in mount, etc... Is this a new OS/installer release where this is showing up, or did a simple kernel upgrade trigger it? If the latter, what kernel version didn't have the above kernel message? -Eric
