If dev->dma_device->params == NULL then the maximum DMA segment size is 64 KB. See also the dma_get_max_seg_size() implementation. This patch fixes the following kernel warning:

DMA-API: infiniband rxe0: mapping sg segment longer than device claims to support [len=126976] [max=65536] WARNING: CPU: 4 PID: 4848 at kernel/dma/debug.c:1220 debug_dma_map_sg+0x3d9/0x450 RIP: 0010:debug_dma_map_sg+0x3d9/0x450 Call Trace: srp_queuecommand+0x626/0x18d0 [ib_srp] scsi_queue_rq+0xd02/0x13e0 [scsi_mod] __blk_mq_try_issue_directly+0x2b3/0x3f0 blk_mq_request_issue_directly+0xac/0xf0 blk_insert_cloned_request+0xdf/0x170 dm_mq_queue_rq+0x43d/0x830 [dm_mod] __blk_mq_try_issue_directly+0x2b3/0x3f0 blk_mq_request_issue_directly+0xac/0xf0 blk_mq_try_issue_list_directly+0xb8/0x170 blk_mq_sched_insert_requests+0x23c/0x3b0 blk_mq_flush_plug_list+0x529/0x730 blk_flush_plug_list+0x21f/0x260 blk_mq_make_request+0x56b/0xf20 generic_make_request+0x196/0x660 submit_bio+0xae/0x290 blkdev_direct_IO+0x822/0x900 generic_file_direct_write+0x110/0x200 __generic_file_write_iter+0x124/0x2a0 blkdev_write_iter+0x168/0x270 aio_write+0x1c4/0x310 io_submit_one+0x971/0x1390 __x64_sys_io_submit+0x12a/0x390 do_syscall_64+0x6f/0x2e0 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Cc: Christoph Hellwig hch@lst.de Cc: stable@vger.kernel.org Fixes: 0b5cb3300ae5 ("RDMA/srp: Increase max_segment_size") Signed-off-by: Bart Van Assche bvanassche@acm.org --- include/rdma/ib_verbs.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h index cca9985b4cbc..0626b62ed107 100644 --- a/include/rdma/ib_verbs.h +++ b/include/rdma/ib_verbs.h @@ -4057,9 +4057,7 @@ static inline void ib_dma_unmap_sg_attrs(struct ib_device *dev, */ static inline unsigned int ib_dma_max_seg_size(struct ib_device *dev) { - struct device_dma_parameters *p = dev->dma_device->dma_parms; - - return p ? p->max_segment_size : UINT_MAX; + return dma_get_max_seg_size(dev->dma_device); }

/**