On 2020/11/11 17:07, Christoph Hellwig wrote: > On Wed, Nov 11, 2020 at 02:16:42PM +0900, Damien Le Moal wrote: >> null_blk always uses the default BLK_SAFE_MAX_SECTORS value for the >> max_hw_sectors and max_sectors queue limits resulting in a maximum >> request size of 127 sectors. When the blocksize setting is larger than >> the default 512B, this maximum request size is not aligned to the >> block size. To emulate a real device more accurately, fix this by >> setting the max_hw_sectors and max_sectors queue limits to a value >> that is aligned to the block size. > > Shouldn't we fix this in the block layer instead of individual drivers? > Yes, I wondered about that too. Probably a good idea to have that generic but that will require changing both blk_queue_logical_block_size() and blk_queue_max_hw_sectors() since drivers may call these in different order. Jens, thoughts ? -- Damien Le Moal Western Digital Research
