On Thu, Apr 18, 2019 at 5:59 AM Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > > On Wed, Apr 17, 2019 at 07:27:24AM +0200, Christoph Hellwig wrote: > > Now that I've fixed the sparc32 iommu code in another thread: can > > you send me your rootfs and qemu arm command line for the failing > > one? I have a hard time parsing your buildbot output. > > FWIW: mmc_blk_data_prep() calls blk_rq_map_sg() with a large offset value. > The old code translated this into: > > blk_bvec_map_sg(q=c77a0000 len=13824 offset=18944) > sg_set_page(sg=c6015000 p=c7efd180 l=13824 o=2560) > > The new code leaves offset unchanged: > > blk_bvec_map_sg(q=c76c0528 len=13824 offset=18944) > sg_set_page(sg=c6035000 p=c7f2af00 l=13824 o=18944) > > Traceback: > > [<c065e3d4>] (blk_rq_map_sg) from [<c0ca1444>] (mmc_blk_data_prep+0x1b0/0x2c8) > [<c0ca1444>] (mmc_blk_data_prep) from [<c0ca15ac>] (mmc_blk_rw_rq_prep+0x50/0x178) > [<c0ca15ac>] (mmc_blk_rw_rq_prep) from [<c0ca48bc>] (mmc_blk_mq_issue_rq+0x290/0x878) > [<c0ca48bc>] (mmc_blk_mq_issue_rq) from [<c0ca52e4>] (mmc_mq_queue_rq+0x128/0x234) > [<c0ca52e4>] (mmc_mq_queue_rq) from [<c066350c>] (blk_mq_dispatch_rq_list+0xc8/0x5e8) > [<c066350c>] (blk_mq_dispatch_rq_list) from [<c06681a8>] (blk_mq_do_dispatch_sched+0x60/0xfc) > [<c06681a8>] (blk_mq_do_dispatch_sched) from [<c06688b8>] (blk_mq_sched_dispatch_requests+0x134/0x1b0) > [<c06688b8>] (blk_mq_sched_dispatch_requests) from [<c0661f08>] (__blk_mq_run_hw_queue+0xa4/0x138) > [<c0661f08>] (__blk_mq_run_hw_queue) from [<c03622a0>] (process_one_work+0x218/0x510) > [<c03622a0>] (process_one_work) from [<c0363230>] (worker_thread+0x44/0x5bc) > > This results in bad data transfers, which ultimately causes the crash. There are several bugs related with kmap(sg_page(sg)), such as: sdhci_kmap_atomic() tmio_mmc_kmap_atomic() wbsd_map_sg() Thanks, Ming Lei