loop0: detected capacity change from 0 to 1024
------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(1)
WARNING: CPU: 1 PID: 7271 at kernel/locking/lockdep.c:237 hlock_class kernel/locking/lockdep.c:-1 [inline]
WARNING: CPU: 1 PID: 7271 at kernel/locking/lockdep.c:237 check_wait_context kernel/locking/lockdep.c:4855 [inline]
WARNING: CPU: 1 PID: 7271 at kernel/locking/lockdep.c:237 __lock_acquire+0x338/0x3058 kernel/locking/lockdep.c:5185
Modules linked in:
CPU: 1 UID: 0 PID: 7271 Comm: syz.0.137 Not tainted 6.15.0-rc4-syzkaller-ge0f4c8dd9d2d #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : hlock_class kernel/locking/lockdep.c:-1 [inline]
pc : check_wait_context kernel/locking/lockdep.c:4855 [inline]
pc : __lock_acquire+0x338/0x3058 kernel/locking/lockdep.c:5185
lr : hlock_class kernel/locking/lockdep.c:237 [inline]
lr : check_wait_context kernel/locking/lockdep.c:4855 [inline]
lr : __lock_acquire+0x32c/0x3058 kernel/locking/lockdep.c:5185
sp : ffff80009d2a72a0
x29: ffff80009d2a7380 x28: 0000000000000001 x27: ffff0000c4cce638
x26: ffff800080b8b8ac x25: 0000000000000000 x24: 0000000000000001
x23: 0000000000000000 x22: 0000000000000000 x21: ffff0000c4ccdb80
x20: ffff800096f4c000 x19: 0000000000000000 x18: 1fffe00036711a76
x17: 0000000000000000 x16: ffff80008ada5d6c x15: 0000000000000001
x14: 1fffe00036711ae2 x13: 0000000000000000 x12: 0000000000000000
x11: ffff800092d13bc0 x10: 000000000001cd8e x9 : 3252cac5a2b99700
x8 : 0000000000000000 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff80009d2a6bf8 x4 : ffff80008f3f4fa0 x3 : ffff8000807ab99c
x2 : 0000000000000001 x1 : 0000000100000001 x0 : 0000000000000000
Call trace:
 hlock_class kernel/locking/lockdep.c:-1 [inline] (P)
 check_wait_context kernel/locking/lockdep.c:4855 [inline] (P)
 __lock_acquire+0x338/0x3058 kernel/locking/lockdep.c:5185 (P)
 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5866
 local_lock_acquire+0x3c/0x98 include/linux/local_lock_internal.h:38
 ___slab_alloc+0xc3c/0xeb4 mm/slub.c:3921
 __slab_alloc+0x74/0xd0 mm/slub.c:3962
 __slab_alloc_node mm/slub.c:4037 [inline]
 slab_alloc_node mm/slub.c:4198 [inline]
 kmem_cache_alloc_noprof+0x2e0/0x3e8 mm/slub.c:4217
 ext4_mb_add_groupinfo+0x5d8/0xcd0 fs/ext4/mballoc.c:3354
 ext4_mb_init_backend fs/ext4/mballoc.c:3433 [inline]
 ext4_mb_init+0x10c4/0x1e64 fs/ext4/mballoc.c:3731
 __ext4_fill_super fs/ext4/super.c:5556 [inline]
 ext4_fill_super+0x4274/0x4e88 fs/ext4/super.c:5726
 get_tree_bdev_flags+0x360/0x414 fs/super.c:1636
 get_tree_bdev+0x2c/0x3c fs/super.c:1659
 ext4_get_tree+0x28/0x38 fs/ext4/super.c:5758
 vfs_get_tree+0x90/0x28c fs/super.c:1759
 do_new_mount+0x228/0x814 fs/namespace.c:3884
 path_mount+0x5b4/0xde0 fs/namespace.c:4211
 do_mount fs/namespace.c:4224 [inline]
 __do_sys_mount fs/namespace.c:4435 [inline]
 __se_sys_mount fs/namespace.c:4412 [inline]
 __arm64_sys_mount+0x3e8/0x468 fs/namespace.c:4412
 __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+0x58/0x150 arch/arm64/kernel/entry-common.c:744
 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:762
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
irq event stamp: 85424
hardirqs last  enabled at (85423): [<ffff800080b6dab4>] seqcount_lockdep_reader_access+0x68/0xc8 include/linux/seqlock.h:74
hardirqs last disabled at (85424): [<ffff800080b8b5c0>] ___slab_alloc+0xc18/0xeb4 mm/slub.c:3921
softirqs last  enabled at (84438): [<ffff8000801fa7b0>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (84436): [<ffff8000801fa77c>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
---[ end trace 0000000000000000 ]---
Unable to handle kernel NULL pointer dereference at virtual address 00000000000000c4
Mem abort info:
  ESR = 0x0000000096000006
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x06: level 2 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000006, ISS2 = 0x00000000
  CM = 0, WnR = 0, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
user pgtable: 4k pages, 48-bit VAs, pgdp=000000010ae73000
[00000000000000c4] pgd=080000010f4a4403, p4d=080000010f4a4403, pud=080000011bca4403, pmd=0000000000000000
Internal error: Oops: 0000000096000006 [#1]  SMP
Modules linked in:
CPU: 1 UID: 0 PID: 7271 Comm: syz.0.137 Tainted: G        W           6.15.0-rc4-syzkaller-ge0f4c8dd9d2d #0 PREEMPT 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : check_wait_context kernel/locking/lockdep.c:4855 [inline]
pc : __lock_acquire+0x34c/0x3058 kernel/locking/lockdep.c:5185
lr : hlock_class kernel/locking/lockdep.c:237 [inline]
lr : check_wait_context kernel/locking/lockdep.c:4855 [inline]
lr : __lock_acquire+0x32c/0x3058 kernel/locking/lockdep.c:5185
sp : ffff80009d2a72a0
x29: ffff80009d2a7380 x28: 0000000000000001 x27: ffff0000c4cce638
x26: ffff800080b8b8ac x25: 0000000000000000 x24: 0000000000000001
x23: 0000000000000000 x22: 0000000000000000 x21: ffff0000c4ccdb80
x20: ffff800096f4c000 x19: 0000000000000000 x18: 1fffe00036711a76
x17: 0000000000000000 x16: ffff80008ada5d6c x15: 0000000000000001
x14: 1fffe00036711ae2 x13: 0000000000000000 x12: 0000000000000000
x11: ffff800092d13bc0 x10: 000000000001cd8e x9 : 00000000000c1881
x8 : 0000000000000000 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff80009d2a6bf8 x4 : ffff80008f3f4fa0 x3 : ffff8000807ab99c
x2 : 0000000000000001 x1 : 0000000100000001 x0 : 0000000000000000
Call trace:
 hlock_class kernel/locking/lockdep.c:228 [inline] (P)
 check_wait_context kernel/locking/lockdep.c:4856 [inline] (P)
 __lock_acquire+0x34c/0x3058 kernel/locking/lockdep.c:5185 (P)
 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5866
 local_lock_acquire+0x3c/0x98 include/linux/local_lock_internal.h:38
 ___slab_alloc+0xc3c/0xeb4 mm/slub.c:3921
 __slab_alloc+0x74/0xd0 mm/slub.c:3962
 __slab_alloc_node mm/slub.c:4037 [inline]
 slab_alloc_node mm/slub.c:4198 [inline]
 kmem_cache_alloc_noprof+0x2e0/0x3e8 mm/slub.c:4217
 ext4_mb_add_groupinfo+0x5d8/0xcd0 fs/ext4/mballoc.c:3354
 ext4_mb_init_backend fs/ext4/mballoc.c:3433 [inline]
 ext4_mb_init+0x10c4/0x1e64 fs/ext4/mballoc.c:3731
 __ext4_fill_super fs/ext4/super.c:5556 [inline]
 ext4_fill_super+0x4274/0x4e88 fs/ext4/super.c:5726
 get_tree_bdev_flags+0x360/0x414 fs/super.c:1636
 get_tree_bdev+0x2c/0x3c fs/super.c:1659
 ext4_get_tree+0x28/0x38 fs/ext4/super.c:5758
 vfs_get_tree+0x90/0x28c fs/super.c:1759
 do_new_mount+0x228/0x814 fs/namespace.c:3884
 path_mount+0x5b4/0xde0 fs/namespace.c:4211
 do_mount fs/namespace.c:4224 [inline]
 __do_sys_mount fs/namespace.c:4435 [inline]
 __se_sys_mount fs/namespace.c:4412 [inline]
 __arm64_sys_mount+0x3e8/0x468 fs/namespace.c:4412
 __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+0x58/0x150 arch/arm64/kernel/entry-common.c:744
 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:762
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
Code: 14000003 d0093feb 912f016b b9402369 (39431113) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	14000003 	b	0xc
   4:	d0093feb 	adrp	x11, 0x127fe000
   8:	912f016b 	add	x11, x11, #0xbc0
   c:	b9402369 	ldr	w9, [x27, #32]
* 10:	39431113 	ldrb	w19, [x8, #196] <-- trapping instruction