====================================================== WARNING: possible circular locking dependency detected 6.12.0-rc6-syzkaller-g8936d33c1f69 #0 Not tainted ------------------------------------------------------ syz.6.664/9482 is trying to acquire lock: ffff0000ef4049d0 (&c->mark_lock){++++}-{0:0}, at: __bch2_disk_reservation_add+0xc4/0x9f4 fs/bcachefs/buckets.c:1170 but task is already holding lock: ffff0000d3f88518 (sb_pagefaults#3){.+.+}-{0:0}, at: do_page_mkwrite+0x140/0x2dc mm/memory.c:3162 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #7 (sb_pagefaults#3){.+.+}-{0:0}: percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1716 [inline] sb_start_pagefault include/linux/fs.h:1881 [inline] bch2_page_mkwrite+0x280/0xe44 fs/bcachefs/fs-io-pagecache.c:614 do_page_mkwrite+0x140/0x2dc mm/memory.c:3162 do_shared_fault mm/memory.c:5373 [inline] do_fault mm/memory.c:5435 [inline] do_pte_missing mm/memory.c:3965 [inline] handle_pte_fault mm/memory.c:5766 [inline] __handle_mm_fault+0x1e1c/0x66e8 mm/memory.c:5909 handle_mm_fault+0x29c/0x8b4 mm/memory.c:6077 do_page_fault+0x570/0x10a8 arch/arm64/mm/fault.c:690 do_translation_fault+0xc4/0x114 arch/arm64/mm/fault.c:783 do_mem_abort+0x74/0x200 arch/arm64/mm/fault.c:919 el0_da+0x60/0x178 arch/arm64/kernel/entry-common.c:604 el0t_64_sync_handler+0xcc/0x108 arch/arm64/kernel/entry-common.c:765 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #6 (&mm->mmap_lock){++++}-{3:3}: __might_fault+0xc4/0x124 mm/memory.c:6716 drm_mode_atomic_ioctl+0x52c/0x13d4 drivers/gpu/drm/drm_atomic_uapi.c:1437 drm_ioctl_kernel+0x26c/0x368 drivers/gpu/drm/drm_ioctl.c:745 drm_ioctl+0x624/0xb14 drivers/gpu/drm/drm_ioctl.c:842 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #5 (crtc_ww_class_acquire){+.+.}-{0:0}: ww_acquire_init include/linux/ww_mutex.h:149 [inline] drm_modeset_acquire_init+0x194/0x330 drivers/gpu/drm/drm_modeset_lock.c:250 drm_client_modeset_commit_atomic+0xe0/0x730 drivers/gpu/drm/drm_client_modeset.c:1007 drm_client_modeset_commit_locked+0xd0/0x4a8 drivers/gpu/drm/drm_client_modeset.c:1171 drm_client_modeset_commit+0x50/0x7c drivers/gpu/drm/drm_client_modeset.c:1197 __drm_fb_helper_restore_fbdev_mode_unlocked+0xd4/0x178 drivers/gpu/drm/drm_fb_helper.c:237 drm_fb_helper_set_par+0xc4/0x110 drivers/gpu/drm/drm_fb_helper.c:1345 fbcon_init+0xf34/0x1eb8 drivers/video/fbdev/core/fbcon.c:1113 visual_init+0x27c/0x548 drivers/tty/vt/vt.c:1011 do_bind_con_driver+0x7dc/0xe04 drivers/tty/vt/vt.c:3833 do_take_over_console+0x4ac/0x5f0 drivers/tty/vt/vt.c:4399 do_fbcon_takeover+0x158/0x260 drivers/video/fbdev/core/fbcon.c:549 do_fb_registered drivers/video/fbdev/core/fbcon.c:2988 [inline] fbcon_fb_registered+0x370/0x4ec drivers/video/fbdev/core/fbcon.c:3008 do_register_framebuffer drivers/video/fbdev/core/fbmem.c:449 [inline] register_framebuffer+0x470/0x610 drivers/video/fbdev/core/fbmem.c:515 __drm_fb_helper_initial_config_and_unlock+0x13b0/0x19a4 drivers/gpu/drm/drm_fb_helper.c:1869 drm_fb_helper_initial_config+0x48/0x64 drivers/gpu/drm/drm_fb_helper.c:1934 drm_fbdev_shmem_client_hotplug+0x158/0x22c drivers/gpu/drm/drm_fbdev_shmem.c:250 drm_client_register+0x144/0x1e0 drivers/gpu/drm/drm_client.c:141 drm_fbdev_shmem_setup+0x11c/0x2cc drivers/gpu/drm/drm_fbdev_shmem.c:309 vkms_create drivers/gpu/drm/vkms/vkms_drv.c:228 [inline] vkms_init+0x4f0/0x600 drivers/gpu/drm/vkms/vkms_drv.c:254 do_one_initcall+0x24c/0x9c0 init/main.c:1269 do_initcall_level+0x154/0x214 init/main.c:1331 do_initcalls+0x58/0xac init/main.c:1347 do_basic_setup+0x8c/0xa0 init/main.c:1366 kernel_init_freeable+0x324/0x478 init/main.c:1580 kernel_init+0x24/0x2a0 init/main.c:1469 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862 -> #4 (&client->modeset_mutex){+.+.}-{3:3}: __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 drm_client_modeset_probe+0x318/0x3f78 drivers/gpu/drm/drm_client_modeset.c:832 __drm_fb_helper_initial_config_and_unlock+0xf0/0x19a4 drivers/gpu/drm/drm_fb_helper.c:1846 drm_fb_helper_initial_config+0x48/0x64 drivers/gpu/drm/drm_fb_helper.c:1934 drm_fbdev_shmem_client_hotplug+0x158/0x22c drivers/gpu/drm/drm_fbdev_shmem.c:250 drm_client_register+0x144/0x1e0 drivers/gpu/drm/drm_client.c:141 drm_fbdev_shmem_setup+0x11c/0x2cc drivers/gpu/drm/drm_fbdev_shmem.c:309 vkms_create drivers/gpu/drm/vkms/vkms_drv.c:228 [inline] vkms_init+0x4f0/0x600 drivers/gpu/drm/vkms/vkms_drv.c:254 do_one_initcall+0x24c/0x9c0 init/main.c:1269 do_initcall_level+0x154/0x214 init/main.c:1331 do_initcalls+0x58/0xac init/main.c:1347 do_basic_setup+0x8c/0xa0 init/main.c:1366 kernel_init_freeable+0x324/0x478 init/main.c:1580 kernel_init+0x24/0x2a0 init/main.c:1469 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862 -> #3 (&helper->lock){+.+.}-{3:3}: __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 __drm_fb_helper_restore_fbdev_mode_unlocked+0xb4/0x178 drivers/gpu/drm/drm_fb_helper.c:228 drm_fb_helper_set_par+0xc4/0x110 drivers/gpu/drm/drm_fb_helper.c:1345 fbcon_init+0xf34/0x1eb8 drivers/video/fbdev/core/fbcon.c:1113 visual_init+0x27c/0x548 drivers/tty/vt/vt.c:1011 do_bind_con_driver+0x7dc/0xe04 drivers/tty/vt/vt.c:3833 do_take_over_console+0x4ac/0x5f0 drivers/tty/vt/vt.c:4399 do_fbcon_takeover+0x158/0x260 drivers/video/fbdev/core/fbcon.c:549 do_fb_registered drivers/video/fbdev/core/fbcon.c:2988 [inline] fbcon_fb_registered+0x370/0x4ec drivers/video/fbdev/core/fbcon.c:3008 do_register_framebuffer drivers/video/fbdev/core/fbmem.c:449 [inline] register_framebuffer+0x470/0x610 drivers/video/fbdev/core/fbmem.c:515 __drm_fb_helper_initial_config_and_unlock+0x13b0/0x19a4 drivers/gpu/drm/drm_fb_helper.c:1869 drm_fb_helper_initial_config+0x48/0x64 drivers/gpu/drm/drm_fb_helper.c:1934 drm_fbdev_shmem_client_hotplug+0x158/0x22c drivers/gpu/drm/drm_fbdev_shmem.c:250 drm_client_register+0x144/0x1e0 drivers/gpu/drm/drm_client.c:141 drm_fbdev_shmem_setup+0x11c/0x2cc drivers/gpu/drm/drm_fbdev_shmem.c:309 vkms_create drivers/gpu/drm/vkms/vkms_drv.c:228 [inline] vkms_init+0x4f0/0x600 drivers/gpu/drm/vkms/vkms_drv.c:254 do_one_initcall+0x24c/0x9c0 init/main.c:1269 do_initcall_level+0x154/0x214 init/main.c:1331 do_initcalls+0x58/0xac init/main.c:1347 do_basic_setup+0x8c/0xa0 init/main.c:1366 kernel_init_freeable+0x324/0x478 init/main.c:1580 kernel_init+0x24/0x2a0 init/main.c:1469 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862 -> #2 (console_lock){+.+.}-{0:0}: console_lock+0x19c/0x1f4 kernel/printk/printk.c:2808 __bch2_print_string_as_lines fs/bcachefs/util.c:267 [inline] bch2_print_string_as_lines+0x2c/0xd4 fs/bcachefs/util.c:286 __bch2_fsck_err+0x1864/0x2544 fs/bcachefs/error.c:411 bch2_check_fix_ptr fs/bcachefs/buckets.c:137 [inline] bch2_check_fix_ptrs+0x19f0/0x515c fs/bcachefs/buckets.c:266 bch2_trigger_extent+0x71c/0x814 fs/bcachefs/buckets.c:856 bch2_key_trigger fs/bcachefs/bkey_methods.h:87 [inline] bch2_gc_mark_key+0x4b4/0xb70 fs/bcachefs/btree_gc.c:634 bch2_gc_btree fs/bcachefs/btree_gc.c:698 [inline] bch2_gc_btrees fs/bcachefs/btree_gc.c:729 [inline] bch2_check_allocations+0x1574/0x48f4 fs/bcachefs/btree_gc.c:1133 bch2_run_recovery_pass+0xe4/0x1d4 fs/bcachefs/recovery_passes.c:185 bch2_run_recovery_passes+0x430/0x71c fs/bcachefs/recovery_passes.c:232 bch2_fs_recovery+0x32d8/0x55a0 fs/bcachefs/recovery.c:861 bch2_fs_start+0x30c/0x53c fs/bcachefs/super.c:1036 bch2_fs_get_tree+0x938/0x1030 fs/bcachefs/fs.c:2170 vfs_get_tree+0x90/0x28c fs/super.c:1814 do_new_mount+0x278/0x900 fs/namespace.c:3507 path_mount+0x590/0xe04 fs/namespace.c:3834 do_mount fs/namespace.c:3847 [inline] __do_sys_mount fs/namespace.c:4057 [inline] __se_sys_mount fs/namespace.c:4034 [inline] __arm64_sys_mount+0x4d4/0x5ac fs/namespace.c:4034 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #1 (&c->fsck_error_msgs_lock){+.+.}-{3:3}: __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 __bch2_fsck_err+0x344/0x2544 fs/bcachefs/error.c:282 bch2_check_fix_ptr fs/bcachefs/buckets.c:137 [inline] bch2_check_fix_ptrs+0x19f0/0x515c fs/bcachefs/buckets.c:266 bch2_trigger_extent+0x71c/0x814 fs/bcachefs/buckets.c:856 bch2_key_trigger fs/bcachefs/bkey_methods.h:87 [inline] bch2_gc_mark_key+0x4b4/0xb70 fs/bcachefs/btree_gc.c:634 bch2_gc_btree fs/bcachefs/btree_gc.c:698 [inline] bch2_gc_btrees fs/bcachefs/btree_gc.c:729 [inline] bch2_check_allocations+0x1574/0x48f4 fs/bcachefs/btree_gc.c:1133 bch2_run_recovery_pass+0xe4/0x1d4 fs/bcachefs/recovery_passes.c:185 bch2_run_recovery_passes+0x430/0x71c fs/bcachefs/recovery_passes.c:232 bch2_fs_recovery+0x32d8/0x55a0 fs/bcachefs/recovery.c:861 bch2_fs_start+0x30c/0x53c fs/bcachefs/super.c:1036 bch2_fs_get_tree+0x938/0x1030 fs/bcachefs/fs.c:2170 vfs_get_tree+0x90/0x28c fs/super.c:1814 do_new_mount+0x278/0x900 fs/namespace.c:3507 path_mount+0x590/0xe04 fs/namespace.c:3834 do_mount fs/namespace.c:3847 [inline] __do_sys_mount fs/namespace.c:4057 [inline] __se_sys_mount fs/namespace.c:4034 [inline] __arm64_sys_mount+0x4d4/0x5ac fs/namespace.c:4034 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #0 (&c->mark_lock){++++}-{0:0}: check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain kernel/locking/lockdep.c:3904 [inline] __lock_acquire+0x33f8/0x77c8 kernel/locking/lockdep.c:5202 lock_acquire+0x240/0x728 kernel/locking/lockdep.c:5825 percpu_down_read+0x5c/0x2e8 include/linux/percpu-rwsem.h:51 __bch2_disk_reservation_add+0xc4/0x9f4 fs/bcachefs/buckets.c:1170 bch2_disk_reservation_add+0x29c/0x4f4 fs/bcachefs/buckets.h:364 __bch2_folio_reservation_get+0x2dc/0x798 fs/bcachefs/fs-io-pagecache.c:428 bch2_folio_reservation_get fs/bcachefs/fs-io-pagecache.c:477 [inline] bch2_page_mkwrite+0xa70/0xe44 fs/bcachefs/fs-io-pagecache.c:637 do_page_mkwrite+0x140/0x2dc mm/memory.c:3162 do_shared_fault mm/memory.c:5373 [inline] do_fault mm/memory.c:5435 [inline] do_pte_missing mm/memory.c:3965 [inline] handle_pte_fault mm/memory.c:5766 [inline] __handle_mm_fault+0x1e1c/0x66e8 mm/memory.c:5909 handle_mm_fault+0x29c/0x8b4 mm/memory.c:6077 do_page_fault+0x570/0x10a8 arch/arm64/mm/fault.c:690 do_translation_fault+0xc4/0x114 arch/arm64/mm/fault.c:783 do_mem_abort+0x74/0x200 arch/arm64/mm/fault.c:919 el0_da+0x60/0x178 arch/arm64/kernel/entry-common.c:604 el0t_64_sync_handler+0xcc/0x108 arch/arm64/kernel/entry-common.c:765 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 other info that might help us debug this: Chain exists of: &c->mark_lock --> &mm->mmap_lock --> sb_pagefaults#3 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- rlock(sb_pagefaults#3); lock(&mm->mmap_lock); lock(sb_pagefaults#3); rlock(&c->mark_lock); *** DEADLOCK *** 2 locks held by syz.6.664/9482: #0: ffff0000cebf6988 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:163 [inline] #0: ffff0000cebf6988 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:6114 [inline] #0: ffff0000cebf6988 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x38/0x2d8 mm/memory.c:6174 #1: ffff0000d3f88518 (sb_pagefaults#3){.+.+}-{0:0}, at: do_page_mkwrite+0x140/0x2dc mm/memory.c:3162 stack backtrace: CPU: 1 UID: 0 PID: 9482 Comm: syz.6.664 Not tainted 6.12.0-rc6-syzkaller-g8936d33c1f69 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:484 (C) __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:120 dump_stack+0x1c/0x28 lib/dump_stack.c:129 print_circular_bug+0x154/0x1c0 kernel/locking/lockdep.c:2074 check_noncircular+0x310/0x404 kernel/locking/lockdep.c:2206 check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain kernel/locking/lockdep.c:3904 [inline] __lock_acquire+0x33f8/0x77c8 kernel/locking/lockdep.c:5202 lock_acquire+0x240/0x728 kernel/locking/lockdep.c:5825 percpu_down_read+0x5c/0x2e8 include/linux/percpu-rwsem.h:51 __bch2_disk_reservation_add+0xc4/0x9f4 fs/bcachefs/buckets.c:1170 bch2_disk_reservation_add+0x29c/0x4f4 fs/bcachefs/buckets.h:364 __bch2_folio_reservation_get+0x2dc/0x798 fs/bcachefs/fs-io-pagecache.c:428 bch2_folio_reservation_get fs/bcachefs/fs-io-pagecache.c:477 [inline] bch2_page_mkwrite+0xa70/0xe44 fs/bcachefs/fs-io-pagecache.c:637 do_page_mkwrite+0x140/0x2dc mm/memory.c:3162 do_shared_fault mm/memory.c:5373 [inline] do_fault mm/memory.c:5435 [inline] do_pte_missing mm/memory.c:3965 [inline] handle_pte_fault mm/memory.c:5766 [inline] __handle_mm_fault+0x1e1c/0x66e8 mm/memory.c:5909 handle_mm_fault+0x29c/0x8b4 mm/memory.c:6077 do_page_fault+0x570/0x10a8 arch/arm64/mm/fault.c:690 do_translation_fault+0xc4/0x114 arch/arm64/mm/fault.c:783 do_mem_abort+0x74/0x200 arch/arm64/mm/fault.c:919 el0_da+0x60/0x178 arch/arm64/kernel/entry-common.c:604 el0t_64_sync_handler+0xcc/0x108 arch/arm64/kernel/entry-common.c:765 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600