A week ago I installed kernel 3.14 on an existing laptop with btrfs install by ubuntu. I upgraded ubuntu to 14.04 a few days ago. I had problems installing a package, then I removed libc6 by mistake, I could no longer boot the system. I booted from a usb disk with ubuntu 14.04. I ran btrfsck on the btrfs partition and find many errors: root@ubuntu:~# btrfsck /dev/sda1 Checking filesystem on /dev/sda1 UUID: a4e2f8a7-3a4e-47a0-8d96-20d70a53af04 checking extents Incorrect local backref count on 772273311744 parent 839903506432 owner 0 offset 0 found 0 wanted 1 back 0x2e5d7f0 Backref disk bytenr does not match extent record, bytenr=772273311744, ref bytenr=0 Backref 772273311744 root 256 owner 1453610 offset 0 num_refs 0 not found in extent tree Incorrect local backref count on 772273311744 root 256 owner 1453610 offset 0 found 1 wanted 0 back 0x7c79cd0 backpointer mismatch on [772273311744 8192] Incorrect local backref count on 772276248576 parent 839903506432 owner 0 offset 0 found 0 wanted 1 back 0x342da60 Backref disk bytenr does not match extent record, bytenr=772276248576, ref bytenr=0 Backref 772276248576 root 256 owner 1453611 offset 0 num_refs 0 not found in extent tree Incorrect local backref count on 772276248576 root 256 owner 1453611 offset 0 found 1 wanted 0 back 0x7c7a5d0 backpointer mismatch on [772276248576 12288] Incorrect local backref count on 772277743616 parent 839903506432 owner 0 offset 0 found 0 wanted 1 back 0x43b1a70 Backref disk bytenr does not match extent record, bytenr=772277743616, ref bytenr=0 Backref 772277743616 root 256 owner 1453614 offset 0 num_refs 0 not found in extent tree Incorrect local backref count on 772277743616 root 256 owner 1453614 offset 0 found 1 wanted 0 back 0x7c7b7d0 backpointer mismatch on [772277743616 16384] Backref 821382955008 root 256 owner 1870931 offset 0 num_refs 0 not found in extent tree Incorrect local backref count on 821382955008 root 256 owner 1870931 offset 0 found 1 wanted 0 back 0xd387530 Incorrect local backref count on 821382955008 parent 839914647552 owner 0 offset 0 found 0 wanted 1 back 0x4565fb0 Backref disk bytenr does not match extent record, bytenr=821382955008, ref bytenr=64 backpointer mismatch on [821382955008 16384] Backref 821382971392 root 256 owner 1870932 offset 0 num_refs 0 not found in extent tree Incorrect local backref count on 821382971392 root 256 owner 1870932 offset 0 found 1 wanted 0 back 0xec1d240 Incorrect local backref count on 821382971392 parent 839914647552 owner 0 offset 0 found 0 wanted 1 back 0x45829c0 Backref disk bytenr does not match extent record, bytenr=821382971392, ref bytenr=64 backpointer mismatch on [821382971392 12288] Backref 821382983680 root 256 owner 1870933 offset 0 num_refs 0 not found in extent tree Incorrect local backref count on 821382983680 root 256 owner 1870933 offset 0 found 1 wanted 0 back 0x6e71620 Incorrect local backref count on 821382983680 parent 839914647552 owner 0 offset 0 found 0 wanted 1 back 0x8c86800 Backref disk bytenr does not match extent record, bytenr=821382983680, ref bytenr=64 backpointer mismatch on [821382983680 8192] Backref 821382991872 root 256 owner 1870934 offset 0 num_refs 0 not found in extent tree Incorrect local backref count on 821382991872 root 256 owner 1870934 offset 0 found 1 wanted 0 back 0x3707e40 Incorrect local backref count on 821382991872 parent 839914647552 owner 0 offset 0 found 0 wanted 1 back 0x8c86c80 Backref disk bytenr does not match extent record, bytenr=821382991872, ref bytenr=64 backpointer mismatch on [821382991872 8192] Backref 821383000064 root 256 owner 1870936 offset 0 num_refs 0 not found in extent tree Incorrect local backref count on 821383000064 root 256 owner 1870936 offset 0 found 1 wanted 0 back 0x3707cc0 Incorrect local backref count on 821383000064 parent 839914647552 owner 0 offset 0 found 0 wanted 1 back 0x47addf0 Backref disk bytenr does not match extent record, bytenr=821383000064, ref bytenr=64 backpointer mismatch on [821383000064 20480] Backref 821383643136 root 256 owner 1871006 offset 0 num_refs 0 not found in extent tree Incorrect local backref count on 821383643136 root 256 owner 1871006 offset 0 found 1 wanted 0 back 0x965b6b0 Incorrect local backref count on 821383643136 parent 839914913792 owner 0 offset 0 found 0 wanted 1 back 0xcf696c0 Backref disk bytenr does not match extent record, bytenr=821383643136, ref bytenr=64 backpointer mismatch on [821383643136 28672] Errors found in extent allocation tree or chunk allocation checking free space cache cache and super generation don't match, space cache will be invalidated checking fs roots root 256 inode 146314 errors 200, dir isize wrong root 256 inode 160861 errors 400, nbytes wrong root 256 inode 967929 errors 1800, odd csum item, some csum missing root 256 inode 996928 errors 1800, odd csum item, some csum missing root 256 inode 1326452 errors 400, nbytes wrong root 256 inode 1326453 errors 400, nbytes wrong root 261 inode 160861 errors 400, nbytes wrong root 261 inode 967929 errors 1800, odd csum item, some csum missing root 261 inode 996928 errors 1800, odd csum item, some csum missing root 261 inode 1326452 errors 400, nbytes wrong root 261 inode 1326453 errors 400, nbytes wrong found 77318565024 bytes used err is 1 total csum bytes: 203137304 total tree bytes: 2158280704 total fs tree bytes: 1807392768 total extent tree bytes: 124895232 btree space waste bytes: 539994004 file data blocks allocated: 3634757378048 referenced 303491842048 Btrfs v3.12 I then ran btrfsck --repair /dev/sda1 I then ran it again and got: btrfsck /dev/sda1 Checking filesystem on /dev/sda1 UUID: a4e2f8a7-3a4e-47a0-8d96-20d70a53af04 checking extents checking free space cache cache and super generation don't match, space cache will be invalidated checking fs roots root 256 inode 160861 errors 400, nbytes wrong root 256 inode 967929 errors 1800, odd csum item, some csum missing root 256 inode 996928 errors 1800, odd csum item, some csum missing root 256 inode 1326452 errors 400, nbytes wrong root 256 inode 1326453 errors 400, nbytes wrong root 261 inode 160861 errors 400, nbytes wrong root 261 inode 967929 errors 1800, odd csum item, some csum missing root 261 inode 996928 errors 1800, odd csum item, some csum missing root 261 inode 1326452 errors 400, nbytes wrong root 261 inode 1326453 errors 400, nbytes wrong found 237847721824 bytes used err is 1 total csum bytes: 203137304 total tree bytes: 2158297088 total fs tree bytes: 1807392768 total extent tree bytes: 124911616 btree space waste bytes: 540009404 file data blocks allocated: 3634757378048 referenced 303491842048 Btrfs v3.12 I ran the btrfsck from this kerenl: Linux ubuntu 3.13.0-24-generic #46-Ubuntu SMP Thu Apr 10 19:11:08 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux I ran an offline smart long test and found no errors on the drive. What is wrong with my file system? What extra info need I supply? -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html