On Tue, Jul 15, 2025 at 06:09:24AM -0700, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: ec4801305969 Merge branches 'for-next/core' and 'for-next/.. > git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci > console output: https://syzkaller.appspot.com/x/log.txt?x=1323ba8c580000 > kernel config: https://syzkaller.appspot.com/x/.config?x=9e99b6fcd403d050 > dashboard link: https://syzkaller.appspot.com/bug?extid=760777ae7038cad77437 > compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7 > userspace arch: arm64 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14d38d82580000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=130ba0f0580000 > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/64d8dc107d9d/disk-ec480130.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/31280b2dee28/vmlinux-ec480130.xz > kernel image: https://storage.googleapis.com/syzbot-assets/b3f9fb3d09f8/Image-ec480130.gz.xz > mounted in repro: https://storage.googleapis.com/syzbot-assets/9b3f4e51e5f9/mount_0.gz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+760777ae7038cad77437@xxxxxxxxxxxxxxxxxxxxxxxxx > > INFO: task syz-executor:6656 blocked for more than 143 > INFO: task syz-executor:6656 blocked for more than 143 seconds. > Not tainted 6.16.0-rc5-syzkaller-gec4801305969 #0 > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > task:syz-executor state:D stack:0 pid:6656 tgid:6656 ppid:1 task_flags:0x400140 flags:0x00000019 > Call trace: > __switch_to+0x414/0x834 arch/arm64/kernel/process.c:742 (T) > context_switch kernel/sched/core.c:5401 [inline] > __schedule+0x1414/0x2a28 kernel/sched/core.c:6790 > __schedule_loop kernel/sched/core.c:6868 [inline] > schedule+0xb4/0x230 kernel/sched/core.c:6883 > io_schedule+0x84/0xf0 kernel/sched/core.c:7728 > folio_wait_bit_common+0x56c/0x9e0 mm/filemap.c:1317 > __folio_lock mm/filemap.c:1675 [inline] > folio_lock include/linux/pagemap.h:1114 [inline] > __filemap_get_folio+0x1ec/0xc38 mm/filemap.c:1928 > truncate_inode_pages_range+0x38c/0xe18 mm/truncate.c:388 > truncate_inode_pages mm/truncate.c:460 [inline] > truncate_inode_pages_final+0x8c/0xbc mm/truncate.c:495 > evict+0x420/0x928 fs/inode.c:812 > dispose_list fs/inode.c:852 [inline] > evict_inodes+0x650/0x6e8 fs/inode.c:906 > generic_shutdown_super+0xa0/0x2b8 fs/super.c:628 > kill_block_super+0x44/0x90 fs/super.c:1755 > deactivate_locked_super+0xc4/0x12c fs/super.c:474 > deactivate_super+0xe0/0x100 fs/super.c:507 > cleanup_mnt+0x31c/0x3ac fs/namespace.c:1417 > __cleanup_mnt+0x20/0x30 fs/namespace.c:1424 > task_work_run+0x1dc/0x260 kernel/task_work.c:227 > resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] > do_notify_resume+0x174/0x1f4 arch/arm64/kernel/entry-common.c:155 > exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:173 [inline] > exit_to_user_mode arch/arm64/kernel/entry-common.c:182 [inline] > el0_svc+0xb8/0x180 arch/arm64/kernel/entry-common.c:880 > el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898 > el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 > > Showing all locks held in the system: > 3 locks held by kworker/u8:1/14: > 1 lock held by khungtaskd/32: > #0: ffff80008f8599c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330 > 2 locks held by pr/ttyAMA0/43: > 2 locks held by getty/6289: > #0: ffff0000d314d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 > #1: ffff80009ba2e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x34c/0xfa4 drivers/tty/n_tty.c:2222 > 1 lock held by syz-executor/6656: > #0: ffff0000c8c7e0e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] > #0: ffff0000c8c7e0e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] > #0: ffff0000c8c7e0e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: deactivate_super+0xd8/0x100 fs/super.c:506 > 1 lock held by syz-executor/6739: > #0: ffff0000dbe180e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] > #0: ffff0000dbe180e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] > #0: ffff0000dbe180e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: deactivate_super+0xd8/0x100 fs/super.c:506 > 1 lock held by syz-executor/6760: > #0: ffff0000c90c20e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] > #0: ffff0000c90c20e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] > #0: ffff0000c90c20e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: deactivate_super+0xd8/0x100 fs/super.c:506 > 1 lock held by syz-executor/6787: > #0: ffff0000d3e2a0e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] > #0: ffff0000d3e2a0e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] > #0: ffff0000d3e2a0e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: deactivate_super+0xd8/0x100 fs/super.c:506 > 1 lock held by syz-executor/6808: > #0: ffff0000d89180e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] > #0: ffff0000d89180e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] > #0: ffff0000d89180e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: deactivate_super+0xd8/0x100 fs/super.c:506 > 1 lock held by syz-executor/6839: > #0: ffff0000f2aba0e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] > #0: ffff0000f2aba0e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] > #0: ffff0000f2aba0e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: deactivate_super+0xd8/0x100 fs/super.c:506 > 1 lock held by syz-executor/6876: > #0: ffff0000dd8f40e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] > #0: ffff0000dd8f40e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] > #0: ffff0000dd8f40e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: deactivate_super+0xd8/0x100 fs/super.c:506 > 1 lock held by syz-executor/6909: > #0: ffff0000eac320e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] > #0: ffff0000eac320e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] > #0: ffff0000eac320e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: deactivate_super+0xd8/0x100 fs/super.c:506 > 1 lock held by syz-executor/6942: > #0: ffff0000d65fa0e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] > #0: ffff0000d65fa0e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] > #0: ffff0000d65fa0e0 (&type->s_umount_key#54){+.+.}-{4:4}, at: deactivate_super+0xd8/0x100 fs/super.c:506 > > ============================================= > > > > --- > This report is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > > If the report is already addressed, let syzbot know by replying with: > #syz fix: exact-commit-title > > If you want syzbot to run the reproducer, reply with: > #syz test: git://repo/address.git branch-or-commit-hash > If you attach or paste a git patch, syzbot will apply it before testing. > > If you want to overwrite report's subsystems, reply with: #syz set subsystems: arm Per the console log, bcachefs wasn't even being tested - very curious how this got flagged as potentially bcachefs. But, all the reports have been from the arm tree, not upstream. I wouldn't be surprised if it's a lost wakeup, those hit arm first due to looser memory ordering.
