ecdfdfdbe4
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 Link: https://lore.kernel.org/r/20191025225830.257535-2-bvanassche@acm.org Cc: <stable@vger.kernel.org> Fixes: 0b5cb3300ae5 ("RDMA/srp: Increase max_segment_size") Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.