Hello Adrian, I have discovered, that beggining with 4.16-rc1 bonnie++ benchmark runs with errors on arc/hsdk board. After bisecting between 4.15 and 4.16-rc1, I have found that errors started after? commit 81196976ed94 (mmc: block: Add blk-mq support). Error message is like: | # bonnie++ -u root -r 256 -s 512 -x 1 -d??/mnt? | Using uid:0, gid:0. | Writing with putc()...random: crng init done | done | Writing intelligently...INFO: task kworker/u8:0:5 blocked for more than 10 seconds. |??????Not tainted 4.15.0-rc3-00012-g81196976ed94-dirty #1 | "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. | kworker/u8:0????D????0?????5??????2 0x00000000 | Workqueue: writeback wb_workfn (flush-179:0) | | Stack Trace: |??__switch_to+0x0/0xac |??__schedule+0x1b8/0x738 |??io_schedule+0x5c/0xc0 |??bit_wait_io+0xc/0x48 |??out_of_line_wait_on_bit+0x78/0xc0 |??do_get_write_access+0x1aa/0x4cc |??jbd2_journal_get_write_access+0x32/0x74 |??__ext4_journal_get_write_access+0x3a/0xac |??ext4_mb_mark_diskspace_used+0x66/0x5b0 |??ext4_mb_new_blocks+0x1ee/0x830 |??ext4_ext_map_blocks+0x504/0xcac |??ext4_map_blocks+0x262/0x5e8 |??mpage_map_and_submit_extent+0xb8/0x648 |??ext4_writepages+0x5ce/0x6b4 |??do_writepages+0x20/0x84 |??__writeback_single_inode+0x2a/0x154 |??wb_writeback+0x538/0xae0 |??wb_workfn+0x17c/0x334 |??process_one_work+0x1a6/0x350 |??worker_thread+0xf2/0x478 |??kthread+0x120/0x13c |??ret_from_fork+0x18/0x1c There are some details of hsdk_defconfig presented bellow: SOFTLOCKUP_DETECTOR=y DETECT_HUNG_TASK=y DEFAULT_HUNG_TASK_TIMEOUT=10 MMC_DW=y MMC_DW_PLTFM=y I have also tested bonnie++ on Wandboard on v4.16-rc5 with the same DEFAULT_HUNG_TASK_TIMEOUT=10, but there were no errors. Even though it is not critical error and we see bonnie++ test proceeds to the end, still it is strange, that some process is running in kernel space for a long time (at least 10sec). What is strange, before metioned commit I can't reproduce this behaviour. I am wondering is this expected behaviour?? Best regards, Evgeniy Didin
