Hello, I'm using archinux with btrfs as root filesystem, kernel 3.15.2, btrfs 3.14.2. System was working fine for more than year, but suddenly after large pacman update filesystem came to unrecoverable error (remounted root ro). I've decided to reboot, and after that btrfs failed to mount: [ 1673.285020] BTRFS: bad tree block start 0 471748608 [ 1673.285071] BTRFS: bad tree block start 0 471748608 [ 1673.317384] BTRFS: open_ctree failed When trying to mount with -o ro, recovery: [ 1788.777081] BTRFS info (device sdc2): enabling auto recovery [ 1788.777088] BTRFS info (device sdc2): disk space caching is enabled [ 1788.778502] BTRFS: bad tree block start 0 471748608 [ 1788.778577] BTRFS: bad tree block start 0 471748608 [ 1788.778657] BTRFS: bad tree block start 0 471748608 [ 1788.778774] BTRFS: bad tree block start 0 471748608 [ 1788.778990] BTRFS: bad tree block start 0 260931584 [ 1788.779221] BTRFS: bad tree block start 0 260931584 [ 1788.779236] BTRFS: failed to read tree root on sdc2 [ 1788.779563] parent transid verify failed on 260562944 wanted 427348 found 427351 [ 1788.779907] parent transid verify failed on 260562944 wanted 427348 found 427351 [ 1788.779908] BTRFS: failed to read tree root on sdc2 [ 1788.780288] parent transid verify failed on 260358144 wanted 427347 found 427351 [ 1788.780571] parent transid verify failed on 260358144 wanted 427347 found 427351 [ 1788.780575] BTRFS: failed to read tree root on sdc2 [ 1788.844215] BTRFS: open_ctree failed Then, i've tried to btrfs check: Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 read block failed check_tree_block Couldn't setup extent tree Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 read block failed check_tree_block Couldn't setup csum tree Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 read block failed check_tree_block Checking filesystem on /dev/sdc2 UUID: 9b5edd54-b3cb-4882-b8d5-ede68717e0aa Critical roots corrupted, unable to fsck the FS Segmentation fault (btrfs[5049]: segfault at 1d3 ip 000000000042e35d sp 00007fff6b317870 error 4 in btrfs[400000+6b000]) As there are errors with csum and extent tree i've tried to reinit them also: btrfs check --init-csum-tree: Creating a new CRC tree Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 read block failed check_tree_block Couldn't setup extent tree Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 read block failed check_tree_block Couldn't setup csum tree Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 read block failed check_tree_block Checking filesystem on /dev/sdc2 UUID: 9b5edd54-b3cb-4882-b8d5-ede68717e0aa Reinit crc root Unable to find block group for 0 btrfs: extent-tree.c:288: find_search_start: Assertion `!(1)' failed. Aborted btrfs check --init-extent-tree: Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 read block failed check_tree_block Couldn't setup extent tree Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 read block failed check_tree_block Couldn't setup csum tree Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 read block failed check_tree_block Checking filesystem on /dev/sdc2 UUID: 9b5edd54-b3cb-4882-b8d5-ede68717e0aa Creating a new extent tree Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 read block failed check_tree_block Error reading root block error pinning down used bytes Segmentation fault ([ 2816.659245] btrfs[5068]: segfault at 1d3 ip 000000000042e35d sp 00007fffc2052420 error 4 in btrfs[400000+6b000]) After all, the last step is to use btrfs restore: btrfs restore -iv /dev/sdc2 /mnt/restore/ Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 Check tree block failed, want=471748608, have=0 read block failed check_tree_block Couldn't setup extent tree Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 Check tree block failed, want=468189184, have=0 read block failed check_tree_block Couldn't setup csum tree Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 Check tree block failed, want=466935808, have=0 read block failed check_tree_block Segmentation fault [ 3324.252370] btrfs[32022]: segfault at fffffffffffffffb ip 000000000042a763 sp 00007fff14488690 error 5 in btrfs[400000+6b000] I've tried this with latest btrfs-progs built from git. Can you please suggest any method to restore files from filesystem? Thanks! Nikolay Shtabel -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
