Hi coly: >> The same operation was performed on three servers, replacing the 12T >> disk with a 16T disk. Only one server triggered the bug. The on-site >What do you mean “replacing 12T disk with a 16T disk” ? Use another 16T SATA disk to replace the 12T SATA disk. Plan to use the 16T hard disk and the original nvme disk to recreate bcache. >> No bcache data clearing operation was performed >What is the “bcache data clearing operation” here? Nothing was done. But I plan to erase the superblock after partitioning the nvme disk. I plan to discard the original nvme disk data by erasing the superblock and wipe-bcache options. >> 3. Replace the 12T SATA disk with a 16T SATA disk >> After shutting down, unplug the 12T hard disk and replace it with a >> 16T hard disk. >It seems you did something bcache doesn’t support. Replace the backing device... You are right. I may have done something that bcache does not support. But I hope that the wrong operation will not cause the system to panic. The consequence I can accept is that the bcache device creation fails. The bcache module can give me a chance to erase the superblock again, instead of entering the CD rescue mode to erase the superblock. >> 7. Repartition again, triggering kernel panic again. >> parted -s --align optimal /dev/nvme2n1 mkpart primary 2048s 1536GiB >> The same operation was performed on the other two servers, and no >> panic was triggered. >I guess this is another undefine operation. I assume the cache device is still references somewhere. A reboot should follow the wipefs. Your guess is correct. In addition, after erasing the superblock information in CD rescue mode, I rebooted into the system where the original panic kernel was located. >> The server with the problem was able to enter the system normally >> after the root of the cache_set structure was determined to be empty. >> I updated the description of the problem in the link below. >No, if you clean up the partition, no cache device will exist. Cache registration won’t treat it as a bcache device. >OK, from the above description, I see you replace the backing device (and I don’t know where the previous data was), then you extend the cache device size. They are all unsupported operations. The behavior here is a bit strange. After partitioning, I may have recreated the bcache device here, which triggered the bcache rigister operation. Then the kernel panicked again. >make-bcache -C /dev/nvme2n1p1 -B /dev/sda --writeback --force --wipe-bcache Thanks.
