====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.2.116/6429 is trying to acquire lock: ffff888074d08ae8 (&sdp->sd_quota_mutex){+.+.}-{3:3}, at: do_qc+0xaf/0x670 fs/gfs2/quota.c:689 but task is already holding lock: ffff88805d545688 (&ip->i_rw_mutex){++++}-{3:3}, at: sweep_bh_for_rgrps fs/gfs2/bmap.c:1526 [inline] ffff88805d545688 (&ip->i_rw_mutex){++++}-{3:3}, at: punch_hole+0x1c7d/0x2d70 fs/gfs2/bmap.c:1850 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&ip->i_rw_mutex){++++}-{3:3}: down_read+0x46/0x2e0 kernel/locking/rwsem.c:1520 __gfs2_iomap_get+0x159/0x13f0 fs/gfs2/bmap.c:856 gfs2_iomap_get+0xc5/0x120 fs/gfs2/bmap.c:1410 bh_get+0x225/0x710 fs/gfs2/quota.c:401 qdsb_get+0x210/0x330 fs/gfs2/quota.c:535 gfs2_quota_hold+0x198/0x5e0 fs/gfs2/quota.c:615 gfs2_dinode_dealloc fs/gfs2/super.c:1228 [inline] evict_unlinked_inode fs/gfs2/super.c:1439 [inline] gfs2_evict_inode+0xdd0/0x1220 fs/gfs2/super.c:1525 evict+0x486/0x870 fs/inode.c:705 do_unlinkat+0x37b/0x570 fs/namei.c:4406 __do_sys_unlink fs/namei.c:4447 [inline] __se_sys_unlink fs/namei.c:4445 [inline] __x64_sys_unlink+0x49/0x50 fs/namei.c:4445 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 -> #0 (&sdp->sd_quota_mutex){+.+.}-{3:3}: 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+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747 do_qc+0xaf/0x670 fs/gfs2/quota.c:689 gfs2_quota_change+0x2b9/0x800 fs/gfs2/quota.c:1289 punch_hole+0x280c/0x2d70 fs/gfs2/bmap.c:1951 gfs2_iomap_end+0x4f6/0x6b0 fs/gfs2/bmap.c:1171 iomap_iter+0x21e/0xec0 fs/iomap/iter.c:79 iomap_file_buffered_write+0xb8b/0xd10 fs/iomap/buffered-io.c:974 gfs2_file_buffered_write+0x4bd/0x820 fs/gfs2/file.c:1060 gfs2_file_write_iter+0x427/0xe10 fs/gfs2/file.c:1158 __kernel_write_iter+0x274/0x670 fs/read_write.c:517 dump_emit_page fs/coredump.c:957 [inline] dump_user_range+0x3f6/0x800 fs/coredump.c:984 elf_core_dump+0x3114/0x36e0 fs/binfmt_elf.c:2184 do_coredump+0x1755/0x2480 fs/coredump.c:833 get_signal+0x1133/0x1400 kernel/signal.c:2888 arch_do_signal_or_restart+0x9c/0x7b0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210 irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:315 exc_page_fault+0x8f/0x110 arch/x86/mm/fault.c:1524 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ip->i_rw_mutex); lock(&sdp->sd_quota_mutex); lock(&ip->i_rw_mutex); lock(&sdp->sd_quota_mutex); *** DEADLOCK *** 5 locks held by syz.2.116/6429: #0: ffff888077f4e418 (sb_writers#29){.+.+}-{0:0}, at: do_coredump+0x1734/0x2480 fs/coredump.c:832 #1: ffff88805d545200 (&sb->s_type->i_mutex_key#34){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #1: ffff88805d545200 (&sb->s_type->i_mutex_key#34){+.+.}-{3:3}, at: gfs2_file_write_iter+0x304/0xe10 fs/gfs2/file.c:1115 #2: ffff888077f4e608 (sb_internal#5){.+.+}-{0:0}, at: gfs2_trans_begin+0x6f/0xe0 fs/gfs2/trans.c:118 #3: ffff888074d09060 (&sdp->sd_log_flush_lock){.+.+}-{3:3}, at: __gfs2_trans_begin+0x511/0x880 fs/gfs2/trans.c:87 #4: ffff88805d545688 (&ip->i_rw_mutex){++++}-{3:3}, at: sweep_bh_for_rgrps fs/gfs2/bmap.c:1526 [inline] #4: ffff88805d545688 (&ip->i_rw_mutex){++++}-{3:3}, at: punch_hole+0x1c7d/0x2d70 fs/gfs2/bmap.c:1850 stack backtrace: CPU: 1 PID: 6429 Comm: syz.2.116 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 check_noncircular+0x2bd/0x3c0 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+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747 do_qc+0xaf/0x670 fs/gfs2/quota.c:689 gfs2_quota_change+0x2b9/0x800 fs/gfs2/quota.c:1289 punch_hole+0x280c/0x2d70 fs/gfs2/bmap.c:1951 gfs2_iomap_end+0x4f6/0x6b0 fs/gfs2/bmap.c:1171 iomap_iter+0x21e/0xec0 fs/iomap/iter.c:79 iomap_file_buffered_write+0xb8b/0xd10 fs/iomap/buffered-io.c:974 gfs2_file_buffered_write+0x4bd/0x820 fs/gfs2/file.c:1060 gfs2_file_write_iter+0x427/0xe10 fs/gfs2/file.c:1158 __kernel_write_iter+0x274/0x670 fs/read_write.c:517 dump_emit_page fs/coredump.c:957 [inline] dump_user_range+0x3f6/0x800 fs/coredump.c:984 elf_core_dump+0x3114/0x36e0 fs/binfmt_elf.c:2184 do_coredump+0x1755/0x2480 fs/coredump.c:833 get_signal+0x1133/0x1400 kernel/signal.c:2888 arch_do_signal_or_restart+0x9c/0x7b0 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210 irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:315 exc_page_fault+0x8f/0x110 arch/x86/mm/fault.c:1524 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x49bb3bc34d Code: Unable to access opcode bytes at 0x49bb3bc323. RSP: 002b:00002000000003f8 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007fe96f5e6180 RCX: 00007fe96f38f749 RDX: 0000200000000000 RSI: 00002000000003f0 RDI: 0000000002000000 RBP: 00007fe96f413f91 R08: 0000200000000400 R09: 0000200000000400 R10: 0000200000000040 R11: 0000000000000206 R12: 0000000000000000 R13: 00007fe96f5e6218 R14: 00007fe96f5e6180 R15: 00007ffc5e274fd8