On 28.04.20 г. 18:22 ч., Anand Jain wrote: > v3 REBASED: Based on the latest misc-next. for for-5.8. > Dropped the following patches as there were concerns about the usage > of error code -EUCLEAN > btrfs: remove identified alien device in open_fs_devices > btrfs: remove identified alien btrfs device in open_fs_devices > > Rmaining 3 patches here have obtained reviewed-by. With this pathset > the pertaining fstests btrfs/197 and btrfs/198 (which tests 3 bugs) > would pass as the patch 2/3 fixed a bug and 3/3 fixed the trigger > of 2 other bugs (patch 1/3 is just a cleanup). Further at the moment > I am not sure if there is any other trigger where it could again leave > an alien device in the fs_devices leading to the same/similar bugs. > > ==== original email ==== > v3: Fix alien device is due to wipefs in Patch4. > Fix a nit in Patch3. > Patches are reordered. > > Alien device is a device in fs_devices list having a different fsid than > the expected fsid or no btrfs_magic. This patch set fixes issues found due > to the same. > > Patch1: is a cleanup patch, not related. > Patch2: fixes failing to mount a degraded RAIDs (RAID1/5/6/10), by > hardening the function btrfs_free_extra_devids(). > Patch3: fixes the missing device (due to alien btrfs-device) not missing in > the userland, by hardening the function btrfs_open_one_device(). > Patch4: fixes the missing device (due to alien device) not missing in > the userland, by returning EUCLEAN in btrfs_read_dev_one_super(). > Patch5: eliminates the source of the alien device in the fs_devices. > > PS: Fundamentally its wrong approach that btrfs-progs deduces the device > missing state in the userland instead of obtaining it from the kernel. > I remember objecting on the btrfs-progs patch which did that, but still > it got merged, bugs in p3 and p4 are its side effects. I wrote > patches to read device_state from the kernel using ioctl, procfs and > sysfs but it didn't get the due attention till a merger. > > Anand Jain (3): > btrfs: drop useless goto in open_fs_devices > btrfs: include non-missing as a qualifier for the latest_bdev > btrfs: free alien device due to device add > > fs/btrfs/volumes.c | 30 ++++++++++++++++++++++-------- > 1 file changed, 22 insertions(+), 8 deletions(-) > One thing I'm not clear is how can we get into a situation of an alien device. I.e devices should be in fs_devices iff they are part of the filesystem, no ?
