[ Re-send to both linux-block and linux-bcache ] Hi, A few days ago, my system refused to boot because it couldn't find the root filesystem anymore. The root filesystem is ext4 on LVM on dm-crypt on bcache, using kernel 4.9.92 (from Debian stretch). Booting from a recovery medium with Kernel 4.16, I got: [ 84.551715] bcache: register_bcache() error /dev/sda4: device already registered [ 84.553188] bcache: register_bcache() error /dev/sdc2: device already registered [ 84.616438] bcache: error on 1330b5f6-0c13-43ec-b925-2ee2734b135f: [ 84.616440] bad btree header at bucket 85065, block 0, 0 keys [ 84.616442] , disabling caching [ 84.616445] bcache: register_cache() registered cache device sdb2 [ 84.616597] bcache: cache_set_free() Cache set 1330b5f6-0c13-43ec-b925-2ee2734b135f unregistered [ 85.375933] sdb: sdb1 sdb2 sdb4 < sdb5 > [ 85.416610] bcache: error on 1330b5f6-0c13-43ec-b925-2ee2734b135f: [ 85.416612] bad btree header at bucket 85065, block 0, 0 keys [ 85.416614] , disabling caching [ 85.416618] bcache: register_cache() registered cache device sdb2 [ 85.416624] bcache: register_bcache() error /dev/sdc2: device already registered [ 85.416626] bcache: register_bcache() error /dev/sda4: device already registered [ 85.416796] bcache: cache_set_free() Cache set 1330b5f6-0c13-43ec-b925-2ee2734b135f unregistered [ 85.488246] bcache: error on 1330b5f6-0c13-43ec-b925-2ee2734b135f: [ 85.488249] bad btree header at bucket 85065, block 0, 0 keys [ 85.488251] , disabling caching [ 85.488254] bcache: register_cache() registered cache device sdb2 [ 85.488429] bcache: cache_set_free() Cache set 1330b5f6-0c13-43ec-b925-2ee2734b135f unregistered [ 85.560003] bcache: error on 1330b5f6-0c13-43ec-b925-2ee2734b135f: [ 85.560006] bad btree header at bucket 85065, block 0, 0 keys [ 85.560008] , disabling caching [ 85.560013] bcache: register_cache() registered cache device sdb2 [ 85.560017] bcache: register_bcache() error /dev/sda4: device already registered [ 85.560217] bcache: cache_set_free() Cache set 1330b5f6-0c13-43ec-b925-2ee2734b135f unregistered [ 85.571950] bcache: register_bcache() error /dev/sdc2: device already registered [ 85.580628] bcache: register_bcache() error /dev/sdc2: device already registered [ 85.761969] bcache: register_bcache() error /dev/sda4: device already registered [ 85.792749] bcache: register_bcache() error /dev/sda4: device already registered [ 85.952931] bcache: register_bcache() error /dev/sda4: device already registered [ 85.955640] bcache: register_bcache() error /dev/sda4: device already registered [...] These are the first messages that mention bcache. Note that the first message is that the device is already registered - is that normal? smartctl does not report any errors on backing or caching disks, and the system was shutdown cleanly. The only possibly related thing that comes to mind is that a few days ago I hibernated and resumed the system (this is something I normally don't do). Resume worked fine as far as I could tell though, and there have been no unclean shutdowns. Is there a way to narrow down what may have caused this corruption? And, is there a way to gracefully recover from this situation without wiping everything? Since the message mentions only problems with one block, can I maybe tell bcache to just ignore/drop this specific block? Thanks! -Nikolaus -- GPG Fingerprint: ED31 791B 2C5C 1613 AF38 8B8A D113 FCAC 3C4E 599F »Time flies like an arrow, fruit flies like a Banana.«
