Re: [PATCH 2/9] xfs: use folios in the buffer cache

[Christoph Hellwig <hch@infradead.org>]

So while this looks good to me,

> +	for (i = 0; i < bp->b_folio_count; i++) {
> +		if (bp->b_folios[i])
> +			__folio_put(bp->b_folios[i]);

The __folio_put here really needs to be folio_put or page alloc
debugging gets very unhappy.

But even with that fixed on top of this patch the first mount just hangs
without a useful kernel backtrace in /proc/*/stack, although running
with the entire ѕeries applied it does pass the basic sanity checking
so far.