Hello, syzbot found the following issue on: HEAD commit: f4345f05c0df Merge tag 'block-6.9-20240510' of git://git.k.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=10c35598980000 kernel config: https://syzkaller.appspot.com/x/.config?x=a450595960709c8 dashboard link: https://syzkaller.appspot.com/bug?extid=6d8d043596bb844b6947 compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-f4345f05.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/5e01373e68f5/vmlinux-f4345f05.xz kernel image: https://storage.googleapis.com/syzbot-assets/dd55eb82d95f/bzImage-f4345f05.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+6d8d043596bb844b6947@xxxxxxxxxxxxxxxxxxxxxxxxx ====================================================== WARNING: possible circular locking dependency detected 6.9.0-rc7-syzkaller-00136-gf4345f05c0df #0 Not tainted ------------------------------------------------------ syz-executor.3/11149 is trying to acquire lock: ffffffff8d937180 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:312 [inline] ffffffff8d937180 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:3752 [inline] ffffffff8d937180 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:3833 [inline] ffffffff8d937180 (fs_reclaim){+.+.}-{0:0}, at: kmalloc_trace+0x51/0x340 mm/slub.c:3998 but task is already holding lock: ffff88806900e5a8 (&dqp->q_qlock){+.+.}-{3:3}, at: xfs_dqlock_nowait fs/xfs/xfs_dquot.h:120 [inline] ffff88806900e5a8 (&dqp->q_qlock){+.+.}-{3:3}, at: xfs_qm_dquot_isolate+0x85/0x1420 fs/xfs/xfs_qm.c:423 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&dqp->q_qlock){+.+.}-{3:3}: __lock_release kernel/locking/lockdep.c:5468 [inline] lock_release+0x33e/0x6c0 kernel/locking/lockdep.c:5774 __mutex_unlock_slowpath+0xa3/0x650 kernel/locking/mutex.c:912 xfs_qm_dqget_cache_lookup+0x428/0x880 fs/xfs/xfs_dquot.c:802 xfs_qm_dqget_inode+0x1e7/0x6d0 fs/xfs/xfs_dquot.c:994 xfs_qm_dqattach_one+0x26f/0x590 fs/xfs/xfs_qm.c:278 xfs_qm_dqattach_locked+0x226/0x2d0 fs/xfs/xfs_qm.c:329 xfs_qm_vop_dqalloc+0x344/0xe40 fs/xfs/xfs_qm.c:1710 xfs_create+0x422/0x1170 fs/xfs/xfs_inode.c:1041 xfs_generic_create+0x631/0x7c0 fs/xfs/xfs_iops.c:199 vfs_mkdir+0x57d/0x820 fs/namei.c:4123 do_mkdirat+0x301/0x3a0 fs/namei.c:4146 __do_sys_mkdir fs/namei.c:4166 [inline] __se_sys_mkdir fs/namei.c:4164 [inline] __ia32_sys_mkdir+0xf0/0x140 fs/namei.c:4164 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x75/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #1 (&xfs_dir_ilock_class){++++}-{3:3}: down_write_nested+0x3d/0x50 kernel/locking/rwsem.c:1695 xfs_ilock+0x2ef/0x420 fs/xfs/xfs_inode.c:206 xfs_reclaim_inode fs/xfs/xfs_icache.c:945 [inline] xfs_icwalk_process_inode fs/xfs/xfs_icache.c:1631 [inline] xfs_icwalk_ag+0xca6/0x1780 fs/xfs/xfs_icache.c:1713 xfs_icwalk+0x57/0x100 fs/xfs/xfs_icache.c:1762 xfs_reclaim_inodes_nr+0x182/0x250 fs/xfs/xfs_icache.c:1011 super_cache_scan+0x409/0x550 fs/super.c:227 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435 shrink_slab+0x18a/0x1310 mm/shrinker.c:662 shrink_one+0x493/0x7c0 mm/vmscan.c:4774 shrink_many mm/vmscan.c:4835 [inline] lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4935 shrink_node mm/vmscan.c:5894 [inline] kswapd_shrink_node mm/vmscan.c:6704 [inline] balance_pgdat+0x10d1/0x1a10 mm/vmscan.c:6895 kswapd+0x5ea/0xbf0 mm/vmscan.c:7164 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #0 (fs_reclaim){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __fs_reclaim_acquire mm/page_alloc.c:3698 [inline] fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3712 might_alloc include/linux/sched/mm.h:312 [inline] slab_pre_alloc_hook mm/slub.c:3752 [inline] slab_alloc_node mm/slub.c:3833 [inline] kmalloc_trace+0x51/0x340 mm/slub.c:3998 kmalloc include/linux/slab.h:628 [inline] add_stack_record_to_list mm/page_owner.c:177 [inline] inc_stack_record_count mm/page_owner.c:219 [inline] __set_page_owner+0x517/0x7a0 mm/page_owner.c:334 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534 prep_new_page mm/page_alloc.c:1541 [inline] get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575 __alloc_pages_bulk+0x742/0x14f0 mm/page_alloc.c:4523 alloc_pages_bulk_array include/linux/gfp.h:202 [inline] xfs_buf_alloc_pages+0x20f/0x9d0 fs/xfs/xfs_buf.c:398 xfs_buf_find_insert fs/xfs/xfs_buf.c:650 [inline] xfs_buf_get_map+0x1e69/0x30d0 fs/xfs/xfs_buf.c:755 xfs_buf_read_map+0xd2/0xb40 fs/xfs/xfs_buf.c:860 xfs_trans_read_buf_map+0x352/0x990 fs/xfs/xfs_trans_buf.c:289 xfs_trans_read_buf fs/xfs/xfs_trans.h:210 [inline] xfs_qm_dqflush+0x224/0x1470 fs/xfs/xfs_dquot.c:1271 xfs_qm_dquot_isolate+0xc8f/0x1420 fs/xfs/xfs_qm.c:465 __list_lru_walk_one+0x19f/0x690 mm/list_lru.c:218 list_lru_walk_one+0xac/0xf0 mm/list_lru.c:266 list_lru_shrink_walk include/linux/list_lru.h:228 [inline] xfs_qm_shrink_scan+0x1fc/0x3f0 fs/xfs/xfs_qm.c:519 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435 shrink_slab+0x18a/0x1310 mm/shrinker.c:662 drop_slab_node mm/vmscan.c:393 [inline] drop_slab+0x14c/0x2c0 mm/vmscan.c:411 drop_caches_sysctl_handler+0x171/0x190 fs/drop_caches.c:68 proc_sys_call_handler+0x4cc/0x6f0 fs/proc/proc_sysctl.c:595 call_write_iter include/linux/fs.h:2110 [inline] iter_file_splice_write+0x906/0x10b0 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0x19b/0x6d0 fs/splice.c:1164 splice_direct_to_actor+0x346/0xa40 fs/splice.c:1108 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x17e/0x250 fs/splice.c:1233 do_sendfile+0xaa8/0xdb0 fs/read_write.c:1295 __do_compat_sys_sendfile fs/read_write.c:1377 [inline] __se_compat_sys_sendfile fs/read_write.c:1366 [inline] __ia32_compat_sys_sendfile+0x163/0x230 fs/read_write.c:1366 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x75/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e other info that might help us debug this: Chain exists of: fs_reclaim --> &xfs_dir_ilock_class --> &dqp->q_qlock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&dqp->q_qlock); lock(&xfs_dir_ilock_class); lock(&dqp->q_qlock); lock(fs_reclaim); *** DEADLOCK *** 2 locks held by syz-executor.3/11149: #0: ffff888021f1e420 (sb_writers#3){.+.+}-{0:0}, at: splice_direct_to_actor+0x346/0xa40 fs/splice.c:1108 #1: ffff88806900e5a8 (&dqp->q_qlock){+.+.}-{3:3}, at: xfs_dqlock_nowait fs/xfs/xfs_dquot.h:120 [inline] #1: ffff88806900e5a8 (&dqp->q_qlock){+.+.}-{3:3}, at: xfs_qm_dquot_isolate+0x85/0x1420 fs/xfs/xfs_qm.c:423 stack backtrace: CPU: 0 PID: 11149 Comm: syz-executor.3 Not tainted 6.9.0-rc7-syzkaller-00136-gf4345f05c0df #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __fs_reclaim_acquire mm/page_alloc.c:3698 [inline] fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3712 might_alloc include/linux/sched/mm.h:312 [inline] slab_pre_alloc_hook mm/slub.c:3752 [inline] slab_alloc_node mm/slub.c:3833 [inline] kmalloc_trace+0x51/0x340 mm/slub.c:3998 kmalloc include/linux/slab.h:628 [inline] add_stack_record_to_list mm/page_owner.c:177 [inline] inc_stack_record_count mm/page_owner.c:219 [inline] __set_page_owner+0x517/0x7a0 mm/page_owner.c:334 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534 prep_new_page mm/page_alloc.c:1541 [inline] get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575 __alloc_pages_bulk+0x742/0x14f0 mm/page_alloc.c:4523 alloc_pages_bulk_array include/linux/gfp.h:202 [inline] xfs_buf_alloc_pages+0x20f/0x9d0 fs/xfs/xfs_buf.c:398 xfs_buf_find_insert fs/xfs/xfs_buf.c:650 [inline] xfs_buf_get_map+0x1e69/0x30d0 fs/xfs/xfs_buf.c:755 xfs_buf_read_map+0xd2/0xb40 fs/xfs/xfs_buf.c:860 xfs_trans_read_buf_map+0x352/0x990 fs/xfs/xfs_trans_buf.c:289 xfs_trans_read_buf fs/xfs/xfs_trans.h:210 [inline] xfs_qm_dqflush+0x224/0x1470 fs/xfs/xfs_dquot.c:1271 xfs_qm_dquot_isolate+0xc8f/0x1420 fs/xfs/xfs_qm.c:465 __list_lru_walk_one+0x19f/0x690 mm/list_lru.c:218 list_lru_walk_one+0xac/0xf0 mm/list_lru.c:266 list_lru_shrink_walk include/linux/list_lru.h:228 [inline] xfs_qm_shrink_scan+0x1fc/0x3f0 fs/xfs/xfs_qm.c:519 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435 shrink_slab+0x18a/0x1310 mm/shrinker.c:662 drop_slab_node mm/vmscan.c:393 [inline] drop_slab+0x14c/0x2c0 mm/vmscan.c:411 drop_caches_sysctl_handler+0x171/0x190 fs/drop_caches.c:68 proc_sys_call_handler+0x4cc/0x6f0 fs/proc/proc_sysctl.c:595 call_write_iter include/linux/fs.h:2110 [inline] iter_file_splice_write+0x906/0x10b0 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0x19b/0x6d0 fs/splice.c:1164 splice_direct_to_actor+0x346/0xa40 fs/splice.c:1108 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x17e/0x250 fs/splice.c:1233 do_sendfile+0xaa8/0xdb0 fs/read_write.c:1295 __do_compat_sys_sendfile fs/read_write.c:1377 [inline] __se_compat_sys_sendfile fs/read_write.c:1366 [inline] __ia32_compat_sys_sendfile+0x163/0x230 fs/read_write.c:1366 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x75/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7353579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f5f455ac EFLAGS: 00000292 ORIG_RAX: 00000000000000bb RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000000004 RDX: 0000000020002080 RSI: 000000000000023b RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 </TASK> syz-executor.3 (11149): drop_caches: 2 syz-executor.3 (11149): drop_caches: 2 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi --- 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 to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
