Fix potential data loss and corruption due to Incorrect BIO Chain Handling

[Christoph Hellwig]

On Thu, Nov 27, 2025 at 03:05:29PM +0800, Stephen Zhang wrote:
> No, they are not using bcache.

Then please figure out how bio_chain_endio even gets called in this
setup.  I think for mainline the approach should be to fix bcache
and eorfs to not call into ->bi_end_io and add a BUG_ON() to
bio_chain_endio to ensure no new callers appear.  I

> If there are no further objections or other insights regarding this issue,
> I will proceed with creating a v2 of this series.

Not sure how that is helpful.  You have a problem on a kernel from stone
age, can't explain what actually happens and propose something that is
mostly a no-op in mainline, with the callers that could even reach the
area being clear API misuse.