Boot hanged after MB2(TBoot-BPMP) done

In that case you have to figure out why it failing to properly close the filesystem before shutting down (e.g., power failure). I am reminded of the old joke: “The guy goes to the doctor, and says ‘it hurts when I do this’. The doctor replies, ‘then don’t do that’.”

In this case there is some truth in the joke. Having a detailed serial console log when the shutdown occurs might be a way to find out why the filesystem is not properly flushed, set to read-only, and unmounted (e.g., perhaps there is a hung process keeping the filesystem from unmounting, although this would not stop flush).

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