On Thu, Mar 24 2016 at 8:23am -0400, Ming Lei <ming.lei@xxxxxxxxxxxxx> wrote: > Hi, > > When I run xfstests generic/081 over virtio-scsi, loop or virtio-blk, > the following snapshot error and IO failure is alwasy observed in > linus v4.5+. The only snapshot specific changes that went into 4.5+ are: 385277b dm snapshot: fix hung bios when copy error occurs 808e621 dm snapshot: disallow the COW and origin devices from being identical Neither of which should result in "Unable to allocate exception" due to -ENOMEM. But commit 385277b does touch relevant code-paths though so you might try reverting it and see if your problem goes away. If that doesn't help then you'll have to do a bisect. Mike > [1], dmesg log > [ 374.794520] EXT4-fs (dm-3): mounted filesystem with ordered data > mode. Opts: (null) > [ 392.894924] device-mapper: snapshots: Invalidating snapshot: Unable > to allocate exception. > [ 392.904760] EXT4-fs warning (device dm-3): ext4_end_bio:314: I/O > error -5 writing to inode 12 (offset 4194304 size 1048576 starting > block 14337) > [ 392.905336] EXT4-fs warning (device dm-3): ext4_end_bio:314: I/O > error -5 writing to inode 12 (offset 0 size 2097152 starting block > 10241) > [ 392.905340] Buffer I/O error on device dm-3, logical block 10241 > [ 392.905342] Buffer I/O error on device dm-3, logical block 10242 > [ 392.905343] Buffer I/O error on device dm-3, logical block 10243 > [ 392.905345] Buffer I/O error on device dm-3, logical block 10244 > [ 392.905349] Buffer I/O error on device dm-3, logical block 10245 > [ 392.905351] Buffer I/O error on device dm-3, logical block 10246 > [ 392.905352] Buffer I/O error on device dm-3, logical block 10247 > [ 392.905353] Buffer I/O error on device dm-3, logical block 10248 > [ 392.905355] Buffer I/O error on device dm-3, logical block 10249 > [ 392.905357] Buffer I/O error on device dm-3, logical block 10250 > [ 392.906708] EXT4-fs warning (device dm-3): ext4_end_bio:314: I/O > error -5 writing to inode 12 (offset 0 size 2097152 starting block > 11265) > [ 392.949341] EXT4-fs warning (device dm-3): ext4_end_bio:314: I/O > error -5 writing to inode 12 (offset 2097152 size 2097152 starting > block 12289) > [ 392.956143] EXT4-fs warning (device dm-3): ext4_end_bio:314: I/O > error -5 writing to inode 12 (offset 2097152 size 2097152 starting > block 13313) -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
