Hi Jens
I added dm-integrity inline mode in the 6.11 merge window. I've found out
that it doesn't work with large bios - the reason is that the function
bio_integrity_add_page refuses to add more metadata than
queue_max_hw_sectors(q). This restriction is no longer needed, because
big bios are split automatically. I'd like to ask you if you could send
this commit to Linus before 6.11 comes out, so that the bug is fixed
before the final release.
Mikulas
From: Mikulas Patocka <mpatocka@xxxxxxxxxx>
bio_integrity_add_page restricts the size of the integrity metadata to
queue_max_hw_sectors(q). This restriction is not needed because oversized
bios are split automatically. This restriction causes problems with
dm-integrity 'inline' mode - if we send a large bio to dm-integrity and
the bio's metadata are larger than queue_max_hw_sectors(q),
bio_integrity_add_page fails and the bio is ended with BLK_STS_RESOURCE
error.
An example that triggers it:
# modprobe brd rd_size=1048576
# dmsetup create in1 --table '0 1847320 integrity /dev/ram0 0 64 D 1 fix_padding'
# dmsetup create in2 --table '0 1847312 integrity /dev/mapper/in1 0 64 I 1 internal_hash:sha512'
# dd if=/dev/zero of=/dev/mapper/in2 bs=1M oflag=direct status=progress
dd: error writing '/dev/mapper/in2': Cannot allocate memory
1+0 records in
0+0 records out
0 bytes copied, 0.00169291 s, 0.0 kB/s
Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Fixes: fb0987682c62 ("dm-integrity: introduce the Inline mode")
Fixes: 0ece1d649b6d ("bio-integrity: create multi-page bvecs in bio_integrity_add_page()")
---
block/bio-integrity.c | 4 ----
1 file changed, 4 deletions(-)
Index: linux-2.6/block/bio-integrity.c
===================================================================
--- linux-2.6.orig/block/bio-integrity.c 2024-07-30 14:06:55.000000000 +0200
+++ linux-2.6/block/bio-integrity.c 2024-09-03 15:49:49.000000000 +0200
@@ -167,10 +167,6 @@ int bio_integrity_add_page(struct bio *b
struct request_queue *q = bdev_get_queue(bio->bi_bdev);
struct bio_integrity_payload *bip = bio_integrity(bio);
- if (((bip->bip_iter.bi_size + len) >> SECTOR_SHIFT) >
- queue_max_hw_sectors(q))
- return 0;
-
if (bip->bip_vcnt > 0) {
struct bio_vec *bv = &bip->bip_vec[bip->bip_vcnt - 1];
bool same_page = false;
