Hi Christoph, Robin, On 25/11/19 11:13 am, Kishon Vijay Abraham I wrote: > Hi, > > On 18/11/19 10:51 PM, Robin Murphy wrote: >> On 16/11/2019 4:35 pm, Christoph Hellwig wrote: >>> On Fri, Nov 15, 2019 at 07:48:23PM +0530, Kishon Vijay Abraham I wrote: >>>> I think the fix on 5.3 was useful for platform drivers (where the platform >>>> driver will set dma_set_mask as 32bits) even when the system itself supports >>>> LPAE. >>> >>> Well, we can also use the bus_dma_mask for PCI(e) root port quirks, >>> as we do that for the VIA ones on x86. But I think the OF parsing code >>> is missing something here, and Robin did plan to look into that. >> >> Right, the correct way to describe this is with "dma-ranges" on the host bridge >> node, and there are patches queued in linux-next to (finally) handle that >> properly for the way we bodge dynamically-discovered endpoints through >> of_dma_configure(). > > Tried linux-next after adding dma-ranges property to the DRA7 RC dt node and > don't see the issue anymore. Using the latest mainline kernel commit d5226fa6dbae0569ee43ecfc08bdcd6770fc4755 (tag: v5.5, origin/master, origin/HEAD) Author: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Date: Sun Jan 26 16:23:03 2020 -0800 Linux 5.5 I see the following warn dump when using a NVMe card with LPAE config enabled nvme 0000:01:00.0: overflow 0x000000027b3be000+270336 of DMA mask ffffffffffffffff bus limit ffffffff ------------[ cut here ]------------ WARNING: CPU: 0 PID: 26 at kernel/dma/direct.c:35 report_addr+0xf0/0xf4 Modules linked in: CPU: 0 PID: 26 Comm: kworker/u4:1 Not tainted 5.5.0-00002-g1383adf7b819 #2 Hardware name: Generic DRA74X (Flattened Device Tree) Workqueue: writeback wb_workfn (flush-259:0) (unwind_backtrace) from [<c020b494>] (show_stack+0x10/0x14) (show_stack) from [<c0a2ae24>] (dump_stack+0x94/0xa8) (dump_stack) from [<c022bbd8>] (__warn+0xbc/0xd8) (__warn) from [<c022bc54>] (warn_slowpath_fmt+0x60/0xb8) (warn_slowpath_fmt) from [<c0299928>] (report_addr+0xf0/0xf4) (report_addr) from [<c0299ab8>] (dma_direct_map_page+0x18c/0x19c) (dma_direct_map_page) from [<c0299b2c>] (dma_direct_map_sg+0x64/0xb4) (dma_direct_map_sg) from [<c071b12c>] (nvme_queue_rq+0x778/0x9ec) (nvme_queue_rq) from [<c050c8c8>] (__blk_mq_try_issue_directly+0x130/0x1bc) (__blk_mq_try_issue_directly) from [<c050d1b8>] (blk_mq_request_issue_directly+0x48/0x78) (blk_mq_request_issue_directly) from [<c050d22c>] (blk_mq_try_issue_list_directly+0x44/0xb8) (blk_mq_try_issue_list_directly) from [<c0511620>] (blk_mq_sched_insert_requests+0xe0/0x154) (blk_mq_sched_insert_requests) from [<c050d13c>] (blk_mq_flush_plug_list+0x150/0x184) (blk_mq_flush_plug_list) from [<c0502ec4>] (blk_flush_plug_list+0xc8/0xe4) (blk_flush_plug_list) from [<c050cc44>] (blk_mq_make_request+0x24c/0x3f0) (blk_mq_make_request) from [<c0501acc>] (generic_make_request+0xb0/0x2d4) (generic_make_request) from [<c0501d34>] (submit_bio+0x44/0x180) (submit_bio) from [<c039ad10>] (mpage_writepages+0xac/0xe8) (mpage_writepages) from [<c02f96dc>] (do_writepages+0x44/0xdc) (do_writepages) from [<c0384830>] (__writeback_single_inode+0x2c/0x1bc) (__writeback_single_inode) from [<c0384b98>] (writeback_sb_inodes+0x1d8/0x404) (writeback_sb_inodes) from [<c0384e1c>] (__writeback_inodes_wb+0x58/0x9c) (__writeback_inodes_wb) from [<c0384ff4>] (wb_writeback+0x194/0x1d8) (wb_writeback) from [<c0386104>] (wb_workfn+0x244/0x33c) (wb_workfn) from [<c0244ff8>] (process_one_work+0x204/0x458) (process_one_work) from [<c0245290>] (worker_thread+0x44/0x598) (worker_thread) from [<c024ab30>] (kthread+0x14c/0x150) (kthread) from [<c02010d8>] (ret_from_fork+0x14/0x3c) Thanks Kishon