Re: [PATCH 02/17] block: warn on too larger integrity allocations

[Christoph Hellwig <hch@lst.de>]

On Mon, Aug 31, 2026 at 11:01:36AM -0700, Darrick J. Wong wrote:
> On Mon, Aug 31, 2026 at 09:39:50AM +0300, Christoph Hellwig wrote:
> > Catch cases where upper layer bugs create larger I/Os than the
> > mempool would return even without dipping into the mempool.
> > 
> > Signed-off-by: Christoph Hellwig <hch@lst.de>
> > ---
> >  block/bio-integrity.c | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/block/bio-integrity.c b/block/bio-integrity.c
> > index b23e2434d80c..d3df726e0f08 100644
> > --- a/block/bio-integrity.c
> > +++ b/block/bio-integrity.c
> > @@ -72,6 +72,7 @@ void bio_integrity_alloc_buf(struct bio *bio, gfp_t gfp, bool zero_buffer)
> >  	unsigned int len = bio_integrity_bytes(bi, bio_sectors(bio));
> >  	void *buf;
> >  
> > +	WARN_ON_ONCE(len > BLK_INTEGRITY_MAX_SIZE);
> 
> Should it fail the bio after complaining, then?

We can't really fail here as the entire path is build around continuing.
This is really a big warning for developer bugs that must not happen
for properly written callers.