BUG: MAX_LOCKDEP_ENTRIES too low!

From: syzbot <syzbot+cd0ec5211ac07c18c049@syzkaller.appspotmail.com>
To: jack@suse.com, linux-kernel@vger.kernel.org,
	syzkaller-bugs@googlegroups.com
Subject: BUG: MAX_LOCKDEP_ENTRIES too low!
Date: Mon, 17 Jun 2019 09:29:09 -0700	[thread overview]
Message-ID: <000000000000ec7273058b877e1f@google.com> (raw)

Hello,

syzbot found the following crash on:

HEAD commit:    f4788d37 Add linux-next specific files for 20190614
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=17f2e3f1a00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=daee2e11d008b604
dashboard link: https://syzkaller.appspot.com/bug?extid=cd0ec5211ac07c18c049
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+cd0ec5211ac07c18c049@syzkaller.appspotmail.com

BUG: MAX_LOCKDEP_ENTRIES too low!
turning off the locking correctness validator.
CPU: 0 PID: 25825 Comm: syz-executor.4 Not tainted 5.2.0-rc4-next-20190614  
#15
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Call Trace:
  __dump_stack lib/dump_stack.c:77 [inline]
  dump_stack+0x172/0x1f0 lib/dump_stack.c:113
  alloc_list_entry kernel/locking/lockdep.c:1219 [inline]
  add_lock_to_list.isra.0.cold+0x11/0x18 kernel/locking/lockdep.c:1240
  check_prev_add kernel/locking/lockdep.c:2449 [inline]
  check_prevs_add kernel/locking/lockdep.c:2502 [inline]
  validate_chain kernel/locking/lockdep.c:2892 [inline]
  __lock_acquire+0x2cb2/0x4af0 kernel/locking/lockdep.c:3885
  lock_acquire+0x16f/0x3f0 kernel/locking/lockdep.c:4418
  __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
  _raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151
  vprintk_emit+0x115/0x700 kernel/printk/printk.c:1966
  vprintk_default+0x28/0x30 kernel/printk/printk.c:2013
  vprintk_func+0x7e/0x189 kernel/printk/printk_safe.c:386
  printk+0xba/0xed kernel/printk/printk.c:2046
  _udf_err+0xdc/0x110 fs/udf/super.c:2286
  udf_read_tagged+0x49c/0x530 fs/udf/misc.c:212
  udf_check_anchor_block+0x1ef/0x680 fs/udf/super.c:1785
  udf_scan_anchors+0x1cf/0x680 fs/udf/super.c:1825
  udf_find_anchor fs/udf/super.c:1882 [inline]
  udf_load_vrs+0x67f/0xc80 fs/udf/super.c:1947
  udf_fill_super+0x7d8/0x16d1 fs/udf/super.c:2140
  mount_bdev+0x304/0x3c0 fs/super.c:1346
  udf_mount+0x35/0x40 fs/udf/super.c:131
  legacy_get_tree+0x108/0x220 fs/fs_context.c:661
  vfs_get_tree+0x8e/0x390 fs/super.c:1476
  do_new_mount fs/namespace.c:2790 [inline]
  do_mount+0x138c/0x1c00 fs/namespace.c:3110
  ksys_mount+0xdb/0x150 fs/namespace.c:3319
  __do_sys_mount fs/namespace.c:3333 [inline]
  __se_sys_mount fs/namespace.c:3330 [inline]
  __x64_sys_mount+0xbe/0x150 fs/namespace.c:3330
  do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4592c9
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7  
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff  
ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fb3d01d1c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00000000004592c9
RDX: 0000000020000140 RSI: 0000000020000180 RDI: 00000000200000c0
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb3d01d26d4
R13: 00000000004c570b R14: 00000000004d9aa0 R15: 00000000ffffffff

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