====================================================== WARNING: possible circular locking dependency detected 6.10.0-rc7-syzkaller-gc912bf709078 #0 Not tainted ------------------------------------------------------ syz.2.8/6514 is trying to acquire lock: ffff0000dc4a8ae8 (&sdp->sd_quota_mutex){+.+.}-{3:3}, at: do_qc+0xac/0x5c8 fs/gfs2/quota.c:720 but task is already holding lock: ffff0000ee9920c8 (&ip->i_rw_mutex){++++}-{3:3}, at: sweep_bh_for_rgrps fs/gfs2/bmap.c:1529 [inline] ffff0000ee9920c8 (&ip->i_rw_mutex){++++}-{3:3}, at: punch_hole+0x1f58/0x2f6c fs/gfs2/bmap.c:1853 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+0x58/0x2fc kernel/locking/rwsem.c:1526 __gfs2_iomap_get+0x124/0x102c fs/gfs2/bmap.c:859 gfs2_iomap_get+0xd8/0x154 fs/gfs2/bmap.c:1413 bh_get+0x1ec/0x688 fs/gfs2/quota.c:417 qdsb_get+0x1c8/0x30c fs/gfs2/quota.c:566 gfs2_quota_hold+0x16c/0x560 fs/gfs2/quota.c:646 punch_hole+0xc10/0x2f6c fs/gfs2/bmap.c:1814 gfs2_iomap_end+0x448/0x618 fs/gfs2/bmap.c:1174 iomap_iter+0x1fc/0x1060 fs/iomap/iter.c:79 iomap_file_buffered_write+0x9ec/0xc74 fs/iomap/buffered-io.c:1023 gfs2_file_buffered_write+0x468/0x76c fs/gfs2/file.c:1060 gfs2_file_write_iter+0x788/0xd80 fs/gfs2/file.c:1164 __kernel_write_iter+0x328/0x77c fs/read_write.c:523 dump_emit_page fs/coredump.c:893 [inline] dump_user_range+0x378/0x6b4 fs/coredump.c:954 elf_core_dump+0x307c/0x3814 fs/binfmt_elf.c:2083 do_coredump+0x14bc/0x2314 fs/coredump.c:767 get_signal+0xf9c/0x1530 kernel/signal.c:2894 do_signal+0x1b0/0x2924 arch/arm64/kernel/signal.c:1308 do_notify_resume+0x74/0x1f4 arch/arm64/kernel/entry-common.c:148 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline] el0_da+0xbc/0x178 arch/arm64/kernel/entry-common.c:581 el0t_64_sync_handler+0xcc/0xfc arch/arm64/kernel/entry-common.c:733 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 -> #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+0x3384/0x763c kernel/locking/lockdep.c:5137 lock_acquire+0x240/0x728 kernel/locking/lockdep.c:5754 __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:608 __mutex_lock kernel/locking/mutex.c:752 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:804 do_qc+0xac/0x5c8 fs/gfs2/quota.c:720 gfs2_quota_change+0x238/0x728 fs/gfs2/quota.c:1315 punch_hole+0x2a28/0x2f6c fs/gfs2/bmap.c:1954 gfs2_iomap_end+0x448/0x618 fs/gfs2/bmap.c:1174 iomap_iter+0x1fc/0x1060 fs/iomap/iter.c:79 iomap_file_buffered_write+0x9ec/0xc74 fs/iomap/buffered-io.c:1023 gfs2_file_buffered_write+0x468/0x76c fs/gfs2/file.c:1060 gfs2_file_write_iter+0x788/0xd80 fs/gfs2/file.c:1164 __kernel_write_iter+0x328/0x77c fs/read_write.c:523 dump_emit_page fs/coredump.c:893 [inline] dump_user_range+0x378/0x6b4 fs/coredump.c:954 elf_core_dump+0x307c/0x3814 fs/binfmt_elf.c:2083 do_coredump+0x14bc/0x2314 fs/coredump.c:767 get_signal+0xf9c/0x1530 kernel/signal.c:2894 do_signal+0x1b0/0x2924 arch/arm64/kernel/signal.c:1308 do_notify_resume+0x74/0x1f4 arch/arm64/kernel/entry-common.c:148 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline] el0_da+0xbc/0x178 arch/arm64/kernel/entry-common.c:581 el0t_64_sync_handler+0xcc/0xfc arch/arm64/kernel/entry-common.c:733 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598 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.2.8/6514: #0: ffff0000d4fb8420 (sb_writers#12){.+.+}-{0:0}, at: do_coredump+0x149c/0x2314 fs/coredump.c:766 #1: ffff0000ee991c30 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:791 [inline] #1: ffff0000ee991c30 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: gfs2_file_write_iter+0x2a8/0xd80 fs/gfs2/file.c:1115 #2: ffff0000d4fb8610 (sb_internal#2){.+.+}-{0:0}, at: gfs2_trans_begin+0x8c/0x100 fs/gfs2/trans.c:118 #3: ffff0000dc4a9060 (&sdp->sd_log_flush_lock){.+.+}-{3:3}, at: __gfs2_trans_begin+0x510/0x908 fs/gfs2/trans.c:87 #4: ffff0000ee9920c8 (&ip->i_rw_mutex){++++}-{3:3}, at: sweep_bh_for_rgrps fs/gfs2/bmap.c:1529 [inline] #4: ffff0000ee9920c8 (&ip->i_rw_mutex){++++}-{3:3}, at: punch_hole+0x1f58/0x2f6c fs/gfs2/bmap.c:1853 stack backtrace: CPU: 0 PID: 6514 Comm: syz.2.8 Not tainted 6.10.0-rc7-syzkaller-gc912bf709078 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:317 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:324 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:114 dump_stack+0x1c/0x28 lib/dump_stack.c:123 print_circular_bug+0x150/0x1b8 kernel/locking/lockdep.c:2060 check_noncircular+0x310/0x404 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+0x3384/0x763c kernel/locking/lockdep.c:5137 lock_acquire+0x240/0x728 kernel/locking/lockdep.c:5754 __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:608 __mutex_lock kernel/locking/mutex.c:752 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:804 do_qc+0xac/0x5c8 fs/gfs2/quota.c:720 gfs2_quota_change+0x238/0x728 fs/gfs2/quota.c:1315 punch_hole+0x2a28/0x2f6c fs/gfs2/bmap.c:1954 gfs2_iomap_end+0x448/0x618 fs/gfs2/bmap.c:1174 iomap_iter+0x1fc/0x1060 fs/iomap/iter.c:79 iomap_file_buffered_write+0x9ec/0xc74 fs/iomap/buffered-io.c:1023 gfs2_file_buffered_write+0x468/0x76c fs/gfs2/file.c:1060 gfs2_file_write_iter+0x788/0xd80 fs/gfs2/file.c:1164 __kernel_write_iter+0x328/0x77c fs/read_write.c:523 dump_emit_page fs/coredump.c:893 [inline] dump_user_range+0x378/0x6b4 fs/coredump.c:954 elf_core_dump+0x307c/0x3814 fs/binfmt_elf.c:2083 do_coredump+0x14bc/0x2314 fs/coredump.c:767 get_signal+0xf9c/0x1530 kernel/signal.c:2894 do_signal+0x1b0/0x2924 arch/arm64/kernel/signal.c:1308 do_notify_resume+0x74/0x1f4 arch/arm64/kernel/entry-common.c:148 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline] el0_da+0xbc/0x178 arch/arm64/kernel/entry-common.c:581 el0t_64_sync_handler+0xcc/0xfc arch/arm64/kernel/entry-common.c:733 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598