I was using chacharand to fill 32 GB SD card (VFAT fs) (maybe 30 MiB/s) with random data, it froze halfway. There was 400 MiB Dirty data. After reboot the filling operation went OK when I used kyber scheduler. System is Fedora 27 on Core i5 2500K / 16 GiB. sysrq: SysRq : Show Blocked State task PC stack pid father device poll D 0 2811838 1 0x00000000 Call Trace: ? __schedule+0x2c2/0x910 schedule+0x2a/0x80 schedule_timeout+0x8a/0x490 ? collect_expired_timers+0xa0/0xa0 msleep+0x24/0x30 usb_port_suspend+0x298/0x430 [usbcore] usb_suspend_both+0x17d/0x200 [usbcore] ? usb_probe_interface+0x300/0x300 [usbcore] usb_runtime_suspend+0x25/0x60 [usbcore] __rpm_callback+0xb7/0x1f0 ? usb_probe_interface+0x300/0x300 [usbcore] rpm_callback+0x1a/0x80 ? usb_probe_interface+0x300/0x300 [usbcore] rpm_suspend+0x11e/0x660 __pm_runtime_suspend+0x36/0x60 usbdev_release+0xb3/0x120 [usbcore] __fput+0xa3/0x1f0 task_work_run+0x82/0xa0 exit_to_usermode_loop+0x91/0xa0 do_syscall_64+0xe7/0x100 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x7f41101c170c RSP: 002b:00007f410e655b80 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 00007f410e655ecb RCX: 00007f41101c170c RDX: 0000000000000000 RSI: 00007f410e655ea0 RDI: 0000000000000007 RBP: 00007f410e655ec4 R08: 0000000000000000 R09: 00007f4100000080 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f410e655c90 R13: 00007f410e655ecb R14: 0000000000000007 R15: 00007f410e655ebb kworker/u8:4 D 0 2978647 2 0x80000000 Workqueue: writeback wb_workfn (flush-8:80) Call Trace: ? __schedule+0x2c2/0x910 schedule+0x2a/0x80 io_schedule+0xd/0x30 blk_mq_get_tag+0x150/0x250 ? wait_woken+0x80/0x80 blk_mq_get_request+0x131/0x450 ? bfq_bio_merge+0xcb/0x100 blk_mq_make_request+0x118/0x6e0 ? blk_queue_enter+0x31/0x2f0 generic_make_request+0xfd/0x2a0 ? submit_bio+0x67/0x140 submit_bio+0x67/0x140 ? guard_bio_eod+0x78/0x150 mpage_writepages+0xa7/0xe0 ? fat_add_cluster+0x60/0x60 [fat] ? do_writepages+0x37/0xc0 ? fat_writepage+0x10/0x10 [fat] do_writepages+0x37/0xc0 ? reacquire_held_locks+0x8f/0x150 ? writeback_sb_inodes+0xef/0x490 ? __writeback_single_inode+0x5a/0x530 __writeback_single_inode+0x5a/0x530 writeback_sb_inodes+0x1ed/0x490 __writeback_inodes_wb+0x55/0xa0 wb_writeback+0x261/0x3f0 ? wb_workfn+0x1fd/0x4f0 wb_workfn+0x1fd/0x4f0 process_one_work+0x206/0x560 worker_thread+0x2c/0x380 ? process_one_work+0x560/0x560 kthread+0x10e/0x130 ? kthread_create_on_node+0x40/0x40 ret_from_fork+0x35/0x40 kworker/0:3 D 0 2979285 2 0x80000000 Workqueue: events_freezable_power_ disk_events_workfn Call Trace: ? __schedule+0x2c2/0x910 schedule+0x2a/0x80 io_schedule+0xd/0x30 blk_mq_get_tag+0x150/0x250 ? wait_woken+0x80/0x80 blk_mq_get_request+0x131/0x450 blk_mq_alloc_request+0x58/0xb0 blk_get_request_flags+0x3b/0x150 scsi_execute+0x33/0x250 scsi_test_unit_ready+0x48/0xb0 sd_check_events+0xc8/0x170 disk_check_events+0x54/0x130 process_one_work+0x206/0x560 worker_thread+0x2c/0x380 ? process_one_work+0x560/0x560 kthread+0x10e/0x130 ? kthread_create_on_node+0x40/0x40 ? SyS_exit+0xe/0x10 ret_from_fork+0x35/0x40 chacharand D 0 2980742 2978974 0x80000002 Call Trace: ? __schedule+0x2c2/0x910 schedule+0x2a/0x80 io_schedule+0xd/0x30 blk_mq_get_tag+0x150/0x250 ? wait_woken+0x80/0x80 blk_mq_get_request+0x131/0x450 ? bfq_bio_merge+0xcb/0x100 blk_mq_make_request+0x118/0x6e0 ? blk_queue_enter+0x31/0x2f0 generic_make_request+0xfd/0x2a0 ? submit_bio+0x67/0x140 submit_bio+0x67/0x140 ? guard_bio_eod+0x78/0x150 __mpage_writepage+0x67e/0x7a0 ? clear_page_dirty_for_io+0x10f/0x240 ? clear_page_dirty_for_io+0x12f/0x240 write_cache_pages+0x1ee/0x460 ? clean_buffers+0x60/0x60 ? fat_add_cluster+0x60/0x60 [fat] mpage_writepages+0x68/0xe0 ? fat_add_cluster+0x60/0x60 [fat] ? do_writepages+0x37/0xc0 ? fat_writepage+0x10/0x10 [fat] do_writepages+0x37/0xc0 ? __filemap_fdatawrite_range+0x99/0xe0 ? __filemap_fdatawrite_range+0xa6/0xe0 __filemap_fdatawrite_range+0xa6/0xe0 ? sync_inode_metadata+0x2a/0x30 fat_flush_inodes+0x25/0x60 [fat] fat_file_release+0x2a/0x40 [fat] __fput+0xa3/0x1f0 task_work_run+0x82/0xa0 do_exit+0x29b/0xbf0 do_group_exit+0x34/0xb0 SyS_exit_group+0xb/0x10 do_syscall_64+0x62/0x100 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x7fd9172b3178 RSP: 002b:00007fffe01eb248 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd9172b3178 RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 RBP: 00007fd9175b08b8 R08: 00000000000000e7 R09: ffffffffffffff80 R10: 00007fffe01eb1d0 R11: 0000000000000246 R12: 00007fd9175b08b8 R13: 00007fd9175b5d60 R14: 0000000000000000 R15: 0000000000000000 (ostnamed) D 0 2981753 1 0x00000004 Call Trace: ? __schedule+0x2c2/0x910 ? rwsem_down_write_failed+0x174/0x260 schedule+0x2a/0x80 rwsem_down_write_failed+0x179/0x260 ? call_rwsem_down_write_failed+0x13/0x20 call_rwsem_down_write_failed+0x13/0x20 down_write+0x3b/0x50 ? do_mount+0x434/0xdb0 do_mount+0x434/0xdb0 ? SyS_statfs+0x1f/0x30 SyS_mount+0x50/0xd0 do_syscall_64+0x62/0x100 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x7f46fb97259a RSP: 002b:00007fff765583a8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f46fb97259a RDX: 0000000000000000 RSI: 0000556304add3e0 RDI: 0000000000000000 RBP: 00007fff76558e00 R08: 0000000000000000 R09: 0000000000000070 R10: 0000000000001027 R11: 0000000000000206 R12: 0000556304ae8a30 R13: 0000556304add3e0 R14: 0000556304a4fb40 R15: 0000000000000015 (ostnamed) D 0 2983102 1 0x00000004 Call Trace: ? __schedule+0x2c2/0x910 ? rwsem_down_write_failed+0x174/0x260 schedule+0x2a/0x80 rwsem_down_write_failed+0x179/0x260 ? call_rwsem_down_write_failed+0x13/0x20 call_rwsem_down_write_failed+0x13/0x20 down_write+0x3b/0x50 ? do_mount+0x434/0xdb0 do_mount+0x434/0xdb0 ? SyS_statfs+0x1f/0x30 SyS_mount+0x50/0xd0 do_syscall_64+0x62/0x100 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x7f46fb97259a RSP: 002b:00007fff765583a8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f46fb97259a RDX: 0000000000000000 RSI: 00005563049ef570 RDI: 0000000000000000 RBP: 00007fff76558e00 R08: 0000000000000000 R09: 00000000000000e0 R10: 0000000000001027 R11: 0000000000000206 R12: 0000556304ae7700 R13: 00005563049ef570 R14: 0000556304a4fb40 R15: 0000000000000015 (ostnamed) D 0 2984561 1 0x00000004 Call Trace: ? __schedule+0x2c2/0x910 ? rwsem_down_write_failed+0x174/0x260 schedule+0x2a/0x80 rwsem_down_write_failed+0x179/0x260 ? call_rwsem_down_write_failed+0x13/0x20 call_rwsem_down_write_failed+0x13/0x20 down_write+0x3b/0x50 ? do_mount+0x434/0xdb0 do_mount+0x434/0xdb0 ? SyS_statfs+0x1f/0x30 SyS_mount+0x50/0xd0 do_syscall_64+0x62/0x100 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x7f46fb97259a RSP: 002b:00007fff765583a8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f46fb97259a RDX: 0000000000000000 RSI: 0000556304addb10 RDI: 0000000000000000 RBP: 00007fff76558e00 R08: 0000000000000000 R09: 00000000000001c0 R10: 0000000000001027 R11: 0000000000000206 R12: 0000556304addd10 R13: 0000556304addb10 R14: 0000556304a4fb40 R15: 0000000000000015 (ostnamed) D 0 2986247 1 0x00000004 Call Trace: ? __schedule+0x2c2/0x910 ? rwsem_down_write_failed+0x174/0x260 schedule+0x2a/0x80 rwsem_down_write_failed+0x179/0x260 ? call_rwsem_down_write_failed+0x13/0x20 call_rwsem_down_write_failed+0x13/0x20 down_write+0x3b/0x50 ? do_mount+0x434/0xdb0 do_mount+0x434/0xdb0 ? SyS_statfs+0x1f/0x30 SyS_mount+0x50/0xd0 do_syscall_64+0x62/0x100 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x7f46fb97259a RSP: 002b:00007fff765583a8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f46fb97259a RDX: 0000000000000000 RSI: 0000556304ae0670 RDI: 0000000000000000 RBP: 00007fff76558e00 R08: 0000000000000000 R09: 00000000000001c0 R10: 0000000000001027 R11: 0000000000000206 R12: 0000556304ae7700 R13: 0000556304ae0670 R14: 0000556304a4fb40 R15: 0000000000000015 (ostnamed) D 0 2987631 1 0x00000000 Call Trace: ? __schedule+0x2c2/0x910 ? rwsem_down_write_failed+0x174/0x260 schedule+0x2a/0x80 rwsem_down_write_failed+0x179/0x260 ? call_rwsem_down_write_failed+0x13/0x20 call_rwsem_down_write_failed+0x13/0x20 down_write+0x3b/0x50 ? do_mount+0x434/0xdb0 do_mount+0x434/0xdb0 ? SyS_statfs+0x1f/0x30 SyS_mount+0x50/0xd0 do_syscall_64+0x62/0x100 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x7f46fb97259a RSP: 002b:00007fff765583a8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f46fb97259a RDX: 0000000000000000 RSI: 0000556304b92bc0 RDI: 0000000000000000 RBP: 00007fff76558e00 R08: 0000000000000000 R09: 00000000000000e0 R10: 0000000000001027 R11: 0000000000000206 R12: 0000556304a12370 R13: 0000556304b92bc0 R14: 0000556304a4fb40 R15: 0000000000000015 systemd[1]: systemd-hostnamed.service: Start operation timed out. Terminating. -- Do what you love because life is too short for anything else.
