<span style="font-family:Arial,Tahoma,Verdana,sans-serif;font-size:12px;background-color:rgb(255,255,255)">Hi.</span><br style="font-family:Arial,Tahoma,Verdana,sans-serif;font-size:12px;background-color:rgb(255,255,255)">
<br style="font-family:Arial,Tahoma,Verdana,sans-serif;font-size:12px;background-color:rgb(255,255,255)"><span style="font-family:Arial,Tahoma,Verdana,sans-serif;font-size:12px;background-color:rgb(255,255,255)">I have a device with XFS on it and if I run xfs_db on it, I get the following: </span><br style="font-family:Arial,Tahoma,Verdana,sans-serif;font-size:12px;background-color:rgb(255,255,255)">
<p id="mailru-webagent-gen-44" style="font-family:Arial,Tahoma,Verdana,sans-serif;font-size:12px;background-color:rgb(255,255,255)">xfs_db> agf 0<br>xfs_db> p<br>magicnum = 0x58414746<br>versionnum = 1<br>seqno = 0<br>
length = 6553344<br>bnoroot = 19432<br>cntroot = 20689<br>bnolevel = 1<br>cntlevel = 1<br>flfirst = 0<br>fllast = 3<br>flcount = 4<br>freeblks = 6529632<br>longest = 6522442<br>btreeblks = 0<br>xfs_db> agfl 0<br>xfs_db> p<br>
bno[0-127] = 0:1 1:2 2:3 3:4<br><br>As you can see, AGFL contains block numbers 1-4.<br><br>As far as I understand, blocks 1-3 contain roots for inode and free space trees, so it seems really suspicious to me that they are listed in free list.<br>
I digged a bit into XFS code inside Linux kernel and did not find any code that will prevent overwriting them when B+trees will start to grow.<br><br>So, the question is did I miss something and this is a normal situation, or is this some kind of bug or corruption? <br>
<br>Thanks in advance. </p>