On 4/9/21 12:40 AM, Christoph Hellwig wrote: > On Thu, Apr 08, 2021 at 02:45:06PM -0700, Guenter Roeck wrote: >> On Wed, Mar 31, 2021 at 09:30:01AM +0200, Christoph Hellwig wrote: >>> Instead of overloading the passthrough fast path with the deprecated >>> block layer bounce buffering let the users that combine an old >>> undermaintained driver with a highmem system pay the price by always >>> falling back to copies in that case. >>> >> >> Hmm, that price is pretty high. When trying to boot sh images from usb, >> it results in a traceback, followed by an i/o error, and the drive >> fails to open. > > That's just because this warning is completely bogus, sorry. > > Does this patch fix the boot for you? > Yes it does. Tested-by: Guenter Roeck <linux@xxxxxxxxxxxx> Thanks, Guenter > diff --git a/block/blk-map.c b/block/blk-map.c > index dac78376acc899..3743158ddaeb76 100644 > --- a/block/blk-map.c > +++ b/block/blk-map.c > @@ -485,9 +485,6 @@ int blk_rq_append_bio(struct request *rq, struct bio *bio) > struct bio_vec bv; > unsigned int nr_segs = 0; > > - if (WARN_ON_ONCE(rq->q->limits.bounce != BLK_BOUNCE_NONE)) > - return -EINVAL; > - > bio_for_each_bvec(bv, bio, iter) > nr_segs++; > >
