====================================================== WARNING: possible circular locking dependency detected 6.11.0-syzkaller-07341-gbaeb9a7d8b60 #0 Not tainted ------------------------------------------------------ kswapd0/77 is trying to acquire lock: ffff8880124ec610 (sb_internal#2){.+.+}-{0:0}, at: gfs2_trans_begin+0x71/0xe0 fs/gfs2/trans.c:118 but task is already holding lock: ffffffff8ea36960 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6821 [inline] ffffffff8ea36960 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbf1/0x3720 mm/vmscan.c:7203 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (fs_reclaim){+.+.}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 __fs_reclaim_acquire mm/page_alloc.c:3825 [inline] fs_reclaim_acquire+0x88/0x140 mm/page_alloc.c:3839 might_alloc include/linux/sched/mm.h:334 [inline] prepare_alloc_pages+0x147/0x5d0 mm/page_alloc.c:4473 __alloc_pages_noprof+0x166/0x6c0 mm/page_alloc.c:4691 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2263 alloc_pages_noprof mm/mempolicy.c:2343 [inline] folio_alloc_noprof+0x128/0x180 mm/mempolicy.c:2350 filemap_alloc_folio_noprof+0xdf/0x500 mm/filemap.c:1008 __filemap_get_folio+0x44e/0xc10 mm/filemap.c:1950 filemap_grab_folio include/linux/pagemap.h:710 [inline] gfs2_unstuff_dinode+0xfb/0x15e0 fs/gfs2/bmap.c:162 fallocate_chunk fs/gfs2/file.c:1190 [inline] __gfs2_fallocate+0xf4e/0x1e00 fs/gfs2/file.c:1337 gfs2_fallocate+0x35c/0x490 fs/gfs2/file.c:1401 vfs_fallocate+0x569/0x6e0 fs/open.c:333 ksys_fallocate fs/open.c:356 [inline] __do_sys_fallocate fs/open.c:364 [inline] __se_sys_fallocate fs/open.c:362 [inline] __x64_sys_fallocate+0xbd/0x110 fs/open.c:362 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (&ip->i_rw_mutex){++++}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 down_write+0x99/0x220 kernel/locking/rwsem.c:1579 gfs2_unstuff_dinode+0xa0/0x15e0 fs/gfs2/bmap.c:161 fallocate_chunk fs/gfs2/file.c:1190 [inline] __gfs2_fallocate+0xf4e/0x1e00 fs/gfs2/file.c:1337 gfs2_fallocate+0x35c/0x490 fs/gfs2/file.c:1401 vfs_fallocate+0x569/0x6e0 fs/open.c:333 ksys_fallocate fs/open.c:356 [inline] __do_sys_fallocate fs/open.c:364 [inline] __se_sys_fallocate fs/open.c:362 [inline] __x64_sys_fallocate+0xbd/0x110 fs/open.c:362 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&sdp->sd_log_flush_lock){++++}-{3:3}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 down_read+0xb1/0xa40 kernel/locking/rwsem.c:1526 __gfs2_trans_begin+0x55d/0x950 fs/gfs2/trans.c:87 gfs2_trans_begin+0x71/0xe0 fs/gfs2/trans.c:118 alloc_dinode+0x2ef/0x5e0 fs/gfs2/inode.c:418 gfs2_create_inode+0xf39/0x1b30 fs/gfs2/inode.c:739 gfs2_atomic_open+0xe5/0x230 fs/gfs2/inode.c:1315 atomic_open fs/namei.c:3455 [inline] lookup_open fs/namei.c:3566 [inline] open_last_lookups fs/namei.c:3694 [inline] path_openat+0x101b/0x3590 fs/namei.c:3930 do_filp_open+0x235/0x490 fs/namei.c:3960 do_sys_openat2+0x13e/0x1d0 fs/open.c:1415 do_sys_open fs/open.c:1430 [inline] __do_sys_open fs/open.c:1438 [inline] __se_sys_open fs/open.c:1434 [inline] __x64_sys_open+0x225/0x270 fs/open.c:1434 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (sb_internal#2){.+.+}-{0:0}: check_prev_add kernel/locking/lockdep.c:3158 [inline] check_prevs_add kernel/locking/lockdep.c:3277 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3901 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5199 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1715 [inline] sb_start_intwrite include/linux/fs.h:1898 [inline] __gfs2_trans_begin+0x471/0x950 fs/gfs2/trans.c:76 gfs2_trans_begin+0x71/0xe0 fs/gfs2/trans.c:118 gfs2_dirty_inode+0x3e0/0x6b0 fs/gfs2/super.c:520 __mark_inode_dirty+0x2ee/0xe90 fs/fs-writeback.c:2493 mark_inode_dirty_sync include/linux/fs.h:2478 [inline] iput+0x1f1/0xa50 fs/inode.c:1906 __dentry_kill+0x20d/0x630 fs/dcache.c:615 shrink_kill+0xa9/0x2c0 fs/dcache.c:1060 shrink_dentry_list+0x2c0/0x5b0 fs/dcache.c:1087 prune_dcache_sb+0x10f/0x180 fs/dcache.c:1168 super_cache_scan+0x34f/0x4b0 fs/super.c:221 do_shrink_slab+0x701/0x1160 mm/shrinker.c:435 shrink_slab+0x1093/0x14d0 mm/shrinker.c:662 shrink_one+0x43b/0x850 mm/vmscan.c:4795 shrink_many mm/vmscan.c:4856 [inline] lru_gen_shrink_node mm/vmscan.c:4934 [inline] shrink_node+0x3799/0x3de0 mm/vmscan.c:5914 kswapd_shrink_node mm/vmscan.c:6742 [inline] balance_pgdat mm/vmscan.c:6934 [inline] kswapd+0x1cbc/0x3720 mm/vmscan.c:7203 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 other info that might help us debug this: Chain exists of: sb_internal#2 --> &ip->i_rw_mutex --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&ip->i_rw_mutex); lock(fs_reclaim); rlock(sb_internal#2); *** DEADLOCK *** 2 locks held by kswapd0/77: #0: ffffffff8ea36960 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat mm/vmscan.c:6821 [inline] #0: ffffffff8ea36960 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0xbf1/0x3720 mm/vmscan.c:7203 #1: ffff8880124ec0e0 (&type->s_umount_key#47){.+.+}-{3:3}, at: super_trylock_shared fs/super.c:562 [inline] #1: ffff8880124ec0e0 (&type->s_umount_key#47){.+.+}-{3:3}, at: super_cache_scan+0x94/0x4b0 fs/super.c:196 stack backtrace: CPU: 0 UID: 0 PID: 77 Comm: kswapd0 Not tainted 6.11.0-syzkaller-07341-gbaeb9a7d8b60 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2203 check_prev_add kernel/locking/lockdep.c:3158 [inline] check_prevs_add kernel/locking/lockdep.c:3277 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3901 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5199 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5822 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1715 [inline] sb_start_intwrite include/linux/fs.h:1898 [inline] __gfs2_trans_begin+0x471/0x950 fs/gfs2/trans.c:76 gfs2_trans_begin+0x71/0xe0 fs/gfs2/trans.c:118 gfs2_dirty_inode+0x3e0/0x6b0 fs/gfs2/super.c:520 __mark_inode_dirty+0x2ee/0xe90 fs/fs-writeback.c:2493 mark_inode_dirty_sync include/linux/fs.h:2478 [inline] iput+0x1f1/0xa50 fs/inode.c:1906 __dentry_kill+0x20d/0x630 fs/dcache.c:615 shrink_kill+0xa9/0x2c0 fs/dcache.c:1060 shrink_dentry_list+0x2c0/0x5b0 fs/dcache.c:1087 prune_dcache_sb+0x10f/0x180 fs/dcache.c:1168 super_cache_scan+0x34f/0x4b0 fs/super.c:221 do_shrink_slab+0x701/0x1160 mm/shrinker.c:435 shrink_slab+0x1093/0x14d0 mm/shrinker.c:662 shrink_one+0x43b/0x850 mm/vmscan.c:4795 shrink_many mm/vmscan.c:4856 [inline] lru_gen_shrink_node mm/vmscan.c:4934 [inline] shrink_node+0x3799/0x3de0 mm/vmscan.c:5914 kswapd_shrink_node mm/vmscan.c:6742 [inline] balance_pgdat mm/vmscan.c:6934 [inline] kswapd+0x1cbc/0x3720 mm/vmscan.c:7203 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244