====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.0.111/4986 is trying to acquire lock: ffff0000dd5e4ae0 (&sdp->sd_quota_mutex){+.+.}-{3:3}, at: do_qc+0xbc/0x648 fs/gfs2/quota.c:682 but task is already holding lock: ffff0000e29405e8 (&ip->i_rw_mutex){++++}-{3:3}, at: __gfs2_iomap_alloc+0x1f4/0x13f4 fs/gfs2/bmap.c:679 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+0x64/0x300 kernel/locking/rwsem.c:1520 __gfs2_iomap_get+0x114/0x1044 fs/gfs2/bmap.c:856 gfs2_iomap_get+0xd4/0x144 fs/gfs2/bmap.c:1396 bh_get+0x1e4/0x604 fs/gfs2/quota.c:385 qdsb_get+0x1d4/0x378 fs/gfs2/quota.c:522 gfs2_quota_hold+0x16c/0x558 fs/gfs2/quota.c:608 gfs2_quota_lock+0xbc/0x744 fs/gfs2/quota.c:1076 gfs2_quota_lock_check fs/gfs2/quota.h:50 [inline] ea_alloc_skeleton+0x18c/0x4d0 fs/gfs2/xattr.c:748 ea_init+0x15c/0x1d0 fs/gfs2/xattr.c:817 __gfs2_xattr_set+0x508/0x9e8 fs/gfs2/xattr.c:1195 __gfs2_set_acl+0xfc/0x184 fs/gfs2/acl.c:103 gfs2_set_acl+0x41c/0x60c fs/gfs2/acl.c:142 set_posix_acl fs/posix_acl.c:1160 [inline] posix_acl_xattr_set+0x2f8/0x394 fs/posix_acl.c:1189 __vfs_setxattr+0x384/0x3a0 fs/xattr.c:182 __vfs_setxattr_noperm+0x120/0x564 fs/xattr.c:216 __vfs_setxattr_locked+0x1ec/0x218 fs/xattr.c:277 vfs_setxattr+0x158/0x2ac fs/xattr.c:309 do_setxattr fs/xattr.c:594 [inline] setxattr+0x258/0x2d8 fs/xattr.c:617 path_setxattr+0x130/0x260 fs/xattr.c:636 __do_sys_setxattr fs/xattr.c:652 [inline] __se_sys_setxattr fs/xattr.c:648 [inline] __arm64_sys_setxattr+0xbc/0xd8 fs/xattr.c:648 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 -> #0 (&sdp->sd_quota_mutex){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2880/0x6800 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x63c kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x1f60 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 do_qc+0xbc/0x648 fs/gfs2/quota.c:682 gfs2_quota_change+0x238/0x718 fs/gfs2/quota.c:1295 gfs2_alloc_blocks+0x13b8/0x1ab8 fs/gfs2/rgrp.c:2494 __gfs2_iomap_alloc+0x388/0x13f4 fs/gfs2/bmap.c:705 gfs2_iomap_begin_write fs/gfs2/bmap.c:1047 [inline] gfs2_iomap_begin+0xad0/0x1330 fs/gfs2/bmap.c:1112 iomap_iter+0x5d4/0x10e0 fs/iomap/iter.c:91 iomap_file_buffered_write+0x19c/0x6b8 fs/iomap/buffered-io.c:846 gfs2_file_buffered_write+0x488/0x7e8 fs/gfs2/file.c:1057 gfs2_file_write_iter+0x3f0/0xc1c fs/gfs2/file.c:1158 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x3ec/0x7f0 fs/read_write.c:584 ksys_write+0x12c/0x224 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:646 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 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 *** 6 locks held by syz.0.111/4986: #0: ffff0000c3e66fe8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x114/0x16c fs/file.c:1038 #1: ffff0000c3c38460 (sb_writers#24){.+.+}-{0:0}, at: vfs_write+0x244/0x7f0 fs/read_write.c:580 #2: ffff0000e2940150 (&sb->s_type->i_mutex_key#30){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #2: ffff0000e2940150 (&sb->s_type->i_mutex_key#30){+.+.}-{3:3}, at: gfs2_file_write_iter+0x2cc/0xc1c fs/gfs2/file.c:1115 #3: ffff0000c3c38650 (sb_internal#6){.+.+}-{0:0}, at: gfs2_trans_begin+0xa8/0x114 fs/gfs2/trans.c:118 #4: ffff0000dd5e5058 (&sdp->sd_log_flush_lock){.+.+}-{3:3}, at: __gfs2_trans_begin+0x500/0x870 fs/gfs2/trans.c:87 #5: ffff0000e29405e8 (&ip->i_rw_mutex){++++}-{3:3}, at: __gfs2_iomap_alloc+0x1f4/0x13f4 fs/gfs2/bmap.c:679 stack backtrace: CPU: 0 PID: 4986 Comm: syz.0.111 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/26/2026 Call trace: dump_backtrace+0x1c0/0x1ec arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106 dump_stack+0x1c/0x5c lib/dump_stack.c:113 print_circular_bug+0x148/0x1b0 kernel/locking/lockdep.c:2048 check_noncircular+0x264/0x2f8 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2880/0x6800 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x63c kernel/locking/lockdep.c:5662 __mutex_lock_common+0x190/0x1f60 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799 do_qc+0xbc/0x648 fs/gfs2/quota.c:682 gfs2_quota_change+0x238/0x718 fs/gfs2/quota.c:1295 gfs2_alloc_blocks+0x13b8/0x1ab8 fs/gfs2/rgrp.c:2494 __gfs2_iomap_alloc+0x388/0x13f4 fs/gfs2/bmap.c:705 gfs2_iomap_begin_write fs/gfs2/bmap.c:1047 [inline] gfs2_iomap_begin+0xad0/0x1330 fs/gfs2/bmap.c:1112 iomap_iter+0x5d4/0x10e0 fs/iomap/iter.c:91 iomap_file_buffered_write+0x19c/0x6b8 fs/iomap/buffered-io.c:846 gfs2_file_buffered_write+0x488/0x7e8 fs/gfs2/file.c:1057 gfs2_file_write_iter+0x3f0/0xc1c fs/gfs2/file.c:1158 call_write_iter include/linux/fs.h:2265 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x3ec/0x7f0 fs/read_write.c:584 ksys_write+0x12c/0x224 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:646 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585