From: Jaehoon Kim Currently, if CCW request creation fails with -EINVAL, the DASD driver returns BLK_STS_IOERR to the block layer. This can happen, for example, when a user-space application such as QEMU passes a misaligned buffer, but the original cause of the error is masked as a generic I/O error. This patch changes the behavior so that -EINVAL is returned as BLK_STS_INVAL, allowing user space to properly detect alignment issues instead of interpreting them as I/O errors. Reviewed-by: Stefan Haberland Cc: stable@vger.kernel.org #6.11+ Signed-off-by: Jaehoon Kim Signed-off-by: Stefan Haberland --- drivers/s390/block/dasd.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index 506a947d00a5..6224ba412623 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -3114,12 +3114,14 @@ static blk_status_t do_dasd_request(struct blk_mq_hw_ctx *hctx, PTR_ERR(cqr) == -ENOMEM || PTR_ERR(cqr) == -EAGAIN) { rc = BLK_STS_RESOURCE; - goto out; + } else if (PTR_ERR(cqr) == -EINVAL) { + rc = BLK_STS_INVAL; + } else { + DBF_DEV_EVENT(DBF_ERR, basedev, + "CCW creation failed (rc=%ld) on request %p", + PTR_ERR(cqr), req); + rc = BLK_STS_IOERR; } - DBF_DEV_EVENT(DBF_ERR, basedev, - "CCW creation failed (rc=%ld) on request %p", - PTR_ERR(cqr), req); - rc = BLK_STS_IOERR; goto out; } /* -- 2.48.1 From: Jaehoon Kim The block layer validates buffer alignment using the device's dma_alignment value. If dma_alignment is smaller than logical_block_size(bp_block) -1, misaligned buffer incorrectly pass validation and propagate to the lower-level driver. This patch adjusts dma_alignment to be at least logical_block_size -1, ensuring that misalignment buffers are properly rejected at the block layer and do not reach the DASD driver unnecessarily. Fixes: 2a07bb64d801 ("s390/dasd: Remove DMA alignment") Reviewed-by: Stefan Haberland Cc: stable@vger.kernel.org #6.11+ Signed-off-by: Jaehoon Kim Signed-off-by: Stefan Haberland --- drivers/s390/block/dasd.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index 6224ba412623..417a2dcf1587 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -334,6 +334,11 @@ static int dasd_state_basic_to_ready(struct dasd_device *device) lim.max_dev_sectors = device->discipline->max_sectors(block); lim.max_hw_sectors = lim.max_dev_sectors; lim.logical_block_size = block->bp_block; + /* + * Adjust dma_alignment to match block_size - 1 + * to ensure proper buffer alignment checks in the block layer. + */ + lim.dma_alignment = lim.logical_block_size - 1; if (device->discipline->has_discard) { unsigned int max_bytes; -- 2.48.1