This driver assumes that bio vectors are memory aligned to the logical block size, so set the queue limit to reflect that. Unless we set up the limit based on the logical block size, we will go out of page bounds in copy_to_nullb / copy_from_nullb. Signed-off-by: Hans Holmberg --- A fixes tag would be in order, but I have not figured out exactly when this became a problem. drivers/block/null_blk/main.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c index f982027e8c85..0ee55f889cfd 100644 --- a/drivers/block/null_blk/main.c +++ b/drivers/block/null_blk/main.c @@ -1949,6 +1949,7 @@ static int null_add_dev(struct nullb_device *dev) .logical_block_size = dev->blocksize, .physical_block_size = dev->blocksize, .max_hw_sectors = dev->max_sectors, + .dma_alignment = dev->blocksize - 1, }; struct nullb *nullb; -- 2.34.1