Since lo_ioctl() is calling sb_set_blocksize() immediately after udf_load_vrs() called sb_set_blocksize(), udf_tread() can't use expected i_blkbits settings... [ 48.685672][ T7322] fs/block_dev.c:135 bdev=0000000014fa0ec2 12 -> 9 [ 48.694675][ T7322] CPU: 4 PID: 7322 Comm: a.out Not tainted 5.1.0+ #196 [ 48.701321][ T7322] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 04/13/2018 [ 48.710265][ T7322] Call Trace: [ 48.710272][ T7322] dump_stack+0xaa/0xd8 [ 48.715633][ T7322] set_blocksize+0xff/0x140 [ 48.822094][ T7322] sb_set_blocksize+0x27/0x70 [ 48.824843][ T7322] udf_load_vrs+0x4b/0x500 [ 48.827322][ T7322] udf_fill_super+0x32e/0x890 [ 48.830125][ T7322] ? snprintf+0x66/0x90 [ 48.832572][ T7322] mount_bdev+0x1c7/0x210 [ 48.835293][ T7322] ? udf_load_vrs+0x500/0x500 [ 48.838009][ T7322] udf_mount+0x34/0x40 [ 48.840504][ T7322] legacy_get_tree+0x2d/0x80 [ 48.843192][ T7322] vfs_get_tree+0x30/0x140 [ 48.845787][ T7322] do_mount+0x830/0xc30 [ 48.848325][ T7322] ? copy_mount_options+0x152/0x1c0 [ 48.851066][ T7322] ksys_mount+0xab/0x120 [ 48.853627][ T7322] __x64_sys_mount+0x26/0x30 [ 48.856168][ T7322] do_syscall_64+0x7c/0x1a0 [ 48.858943][ T7322] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.978376][ T7332] fs/block_dev.c:135 bdev=0000000014fa0ec2 9 -> 12 [ 49.079394][ T7332] CPU: 6 PID: 7332 Comm: a.out Not tainted 5.1.0+ #196 [ 49.082769][ T7332] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 04/13/2018 [ 49.089007][ T7332] Call Trace: [ 49.091410][ T7332] dump_stack+0xaa/0xd8 [ 49.094053][ T7332] set_blocksize+0xff/0x140 [ 49.096734][ T7332] lo_ioctl+0x570/0xc60 [ 49.099366][ T7332] ? loop_queue_work+0xdb0/0xdb0 [ 49.102079][ T7332] blkdev_ioctl+0xb69/0xc10 [ 49.104667][ T7332] block_ioctl+0x56/0x70 [ 49.107267][ T7332] ? blkdev_fallocate+0x230/0x230 [ 49.110035][ T7332] do_vfs_ioctl+0xc1/0x7e0 [ 49.112728][ T7332] ? tomoyo_file_ioctl+0x23/0x30 [ 49.115452][ T7332] ksys_ioctl+0x94/0xb0 [ 49.118008][ T7332] __x64_sys_ioctl+0x1e/0x30 [ 49.120686][ T7332] do_syscall_64+0x7c/0x1a0 [ 49.123470][ T7332] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 49.163269][ T7322] UDF-fs: error (device loop2): udf_read_tagged: read failed, block=256, location=256 [ 51.009494][ T7322] grow_dev_page: 5 callbacks suppressed [ 51.009509][ T7322] fs/buffer.c:960 bdev=0000000014fa0ec2 block=32 inode->i_blkbits=12 index=4 size=512 [ 51.016583][ T7322] fs/buffer.c:967 bdev=0000000014fa0ec2 block=32 index=4 size=512 bh->b_size=512 [ 55.046361][ T7322] grow_dev_page: 1177059 callbacks suppressed [ 55.046366][ T7322] fs/buffer.c:960 bdev=0000000014fa0ec2 block=32 inode->i_blkbits=12 index=4 size=512 [ 55.054903][ T7322] grow_dev_page: 1177037 callbacks suppressed [ 55.054906][ T7322] fs/buffer.c:967 bdev=0000000014fa0ec2 block=32 index=4 size=512 bh->b_size=512 [ 56.055187][ T7322] grow_dev_page: 1279065 callbacks suppressed [ 56.055191][ T7322] fs/buffer.c:960 bdev=0000000014fa0ec2 block=32 inode->i_blkbits=12 index=4 size=512 [ 56.064443][ T7322] grow_dev_page: 1279065 callbacks suppressed [ 56.064446][ T7322] fs/buffer.c:967 bdev=0000000014fa0ec2 block=32 index=4 size=512 bh->b_size=512 [ 92.282798][ T1097] INFO: task a.out:7322 can't die for more than 30 seconds. [ 92.285926][ T1097] a.out R running task 0 7322 1 0x80004004 [ 92.289143][ T1097] Call Trace: [ 92.291175][ T1097] __schedule+0x2eb/0x600 [ 92.293354][ T1097] ? apic_timer_interrupt+0xa/0x20 [ 92.295802][ T1097] ? xas_load+0x13/0xd0 [ 92.298079][ T1097] ? __switch_to_asm+0x40/0x70 [ 92.300466][ T1097] ? __switch_to_asm+0x34/0x70 [ 92.302890][ T1097] ? __switch_to_asm+0x40/0x70 [ 92.305299][ T1097] ? __switch_to_asm+0x34/0x70 [ 92.307621][ T1097] ? __switch_to_asm+0x40/0x70 [ 92.309908][ T1097] ? __switch_to_asm+0x34/0x70 [ 92.312161][ T1097] ? debug_smp_processor_id+0x2b/0x130 [ 92.314532][ T1097] ? xas_start+0xa7/0x110 [ 92.317139][ T1097] ? xas_load+0x3d/0xd0 [ 92.319674][ T1097] ? xas_start+0xa7/0x110 [ 92.321746][ T1097] ? xas_load+0x3d/0xd0 [ 92.323831][ T1097] ? find_get_entry+0x172/0x220 [ 92.326115][ T1097] ? __this_cpu_preempt_check+0x37/0x120 [ 92.328714][ T1097] ? __find_get_block+0x485/0x610 [ 92.331096][ T1097] ? _raw_spin_trylock+0x12/0x50 [ 92.333402][ T1097] ? __getblk_gfp+0xd9/0x4a0 [ 92.335617][ T1097] ? __bread_gfp+0x2d/0x130 [ 92.338410][ T1097] ? udf_tread+0x48/0x70 [ 92.341144][ T1097] ? udf_read_tagged+0x40/0x1a0 [ 92.343537][ T1097] ? udf_check_anchor_block+0x94/0x190 [ 92.346054][ T1097] ? udf_scan_anchors+0x12b/0x250 [ 92.348480][ T1097] ? udf_load_vrs+0x2b7/0x500 [ 92.350732][ T1097] ? udf_fill_super+0x32e/0x890 [ 92.353172][ T1097] ? snprintf+0x66/0x90 [ 92.355256][ T1097] ? mount_bdev+0x1c7/0x210 [ 92.358214][ T1097] ? udf_load_vrs+0x500/0x500 [ 92.361251][ T1097] ? udf_mount+0x34/0x40 [ 92.363661][ T1097] ? legacy_get_tree+0x2d/0x80 [ 92.366298][ T1097] ? vfs_get_tree+0x30/0x140 [ 92.368955][ T1097] ? do_mount+0x830/0xc30 [ 92.371468][ T1097] ? copy_mount_options+0x152/0x1c0 [ 92.374098][ T1097] ? ksys_mount+0xab/0x120 [ 92.376605][ T1097] ? __x64_sys_mount+0x26/0x30 [ 92.379553][ T1097] ? do_syscall_64+0x7c/0x1a0 [ 92.381615][ T1097] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 92.383942][ T1097] INFO: task a.out:7332 can't die for more than 30 seconds. [ 92.387037][ T1097] a.out D 0 7332 1 0x00004004 [ 92.389621][ T1097] Call Trace: [ 92.391297][ T1097] __schedule+0x2e3/0x600 [ 92.393313][ T1097] ? __switch_to_asm+0x40/0x70 [ 92.395486][ T1097] schedule+0x32/0xc0 [ 92.404871][ T1097] rwsem_down_read_failed+0xf0/0x1a0 [ 92.407605][ T1097] down_read+0x2f/0x40 [ 92.417196][ T1097] ? down_read+0x2f/0x40 [ 92.419579][ T1097] __get_super.part.12+0x113/0x140 [ 92.422165][ T1097] get_super+0x2d/0x40 [ 92.424559][ T1097] fsync_bdev+0x19/0x80 [ 92.427012][ T1097] invalidate_partition+0x35/0x60 [ 92.429588][ T1097] rescan_partitions+0x53/0x4b0 [ 92.432137][ T1097] __blkdev_reread_part+0x6a/0xa0 [ 92.434856][ T1097] blkdev_reread_part+0x24/0x40 [ 92.438203][ T1097] loop_reread_partitions+0x1e/0x60 [ 92.440909][ T1097] loop_set_status+0x4fa/0x5a0 [ 92.443427][ T1097] loop_set_status64+0x55/0x90 [ 92.445962][ T1097] lo_ioctl+0x651/0xc60 [ 92.448427][ T1097] ? loop_queue_work+0xdb0/0xdb0 [ 92.451260][ T1097] blkdev_ioctl+0xb69/0xc10 [ 92.453771][ T1097] block_ioctl+0x56/0x70 [ 92.456284][ T1097] ? blkdev_fallocate+0x230/0x230 [ 92.458957][ T1097] do_vfs_ioctl+0xc1/0x7e0 [ 92.461639][ T1097] ? tomoyo_file_ioctl+0x23/0x30 [ 92.464071][ T1097] ksys_ioctl+0x94/0xb0 [ 92.466394][ T1097] __x64_sys_ioctl+0x1e/0x30 [ 92.468879][ T1097] do_syscall_64+0x7c/0x1a0 [ 92.471339][ T1097] entry_SYSCALL_64_after_hwframe+0x44/0xa9