btrfs-progs: print csum values on superblock mismatch #985
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[BUG] When a device replace failed, e.g. try to replace a device on a RO mounted btrfs, the error message is incorrectly broken into two lines: [adam@btrfs-vm ~]$ sudo btrfs replace start -fB 1 /dev/test/scratch3 /mnt/btrfs/ Performing full device TRIM /dev/mapper/test-scratch3 (10.00GiB) ... ERROR: ioctl(DEV_REPLACE_START) failed on "/mnt/btrfs/": Read-only file system [adam@btrfs-vm ~]$ Note the newline after the "Read-only file system" error message. [CAUSE] Inside cmd_replace_start(), if the ioctl failed we need to handle the error messages different depeneding on start_args.result. If the result is not BTRFS_IOCTL_DEV_REPLACE_RESULT_NO_RESULT we will append extra info to the error message. But the initial error message is using error(), which implies a newline. This results the above incorrectly splitted error message. [FIX] Instead of manually appending an extra reason to the existing error message, just do different output depending on the start_args.result in the first place. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Anand Jain <anand.jain@oracle.com>
If in btrfs_check_super() we find that the superblock has a csum mismatch, print the wanted and found values, just as we do for metadata in __csum_tree_block_size(). When hex-editing a btrfs image, it's useful to use btrfs check to calculate what the new csum should be. Unfortunately at present this only works for trees and not for the superblock, meaning you have to use the much more wordy `btrfs inspect-internal`. Signed-off-by: Mark Harmstone <maharmstone@fb.com>
kdave
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Printing the expected and found checksum makes sense but I find the reasoning a bit fishy, why do you need to hex-edit images or not want to use the existing inspect tool. |
kdave
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If in btrfs_check_super() we find that the superblock has a csum mismatch, print the wanted and found values, just as we do for metadata in __csum_tree_block_size(). When hex-editing a btrfs image, it's useful to use btrfs check to calculate what the new csum should be. Unfortunately at present this only works for trees and not for the superblock, meaning you have to use the much more wordy `btrfs inspect-internal`. Pull-request: #985 Signed-off-by: Mark Harmstone <maharmstone@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
Thanks Dave. Creating faulty images for a btrfs-check test was one reason. It's easy to fix the metadata csum because check itself tells you what it should be; for the superblock, not so much. |
adam900710
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If in btrfs_check_super() we find that the superblock has a csum mismatch, print the wanted and found values, just as we do for metadata in __csum_tree_block_size(). When hex-editing a btrfs image, it's useful to use btrfs check to calculate what the new csum should be. Unfortunately at present this only works for trees and not for the superblock, meaning you have to use the much more wordy `btrfs inspect-internal`. Pull-request: #985 Signed-off-by: Mark Harmstone <maharmstone@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
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If in btrfs_check_super() we find that the superblock has a csum mismatch, print the wanted and found values, just as we do for metadata in __csum_tree_block_size().
When hex-editing a btrfs image, it's useful to use btrfs check to calculate what the new csum should be. Unfortunately at present this only works for trees and not for the superblock, meaning you have to use the much more wordy
btrfs inspect-internal.