[syzbot] [btrfs?] WARNING in create_pending_snapshot

[syzbot] [btrfs?] WARNING in create_pending_snapshot

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    305230142ae0 Merge tag 'pm-6.7-rc1-2' of git://git.kernel...
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=11777b60e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=4d81015bc10889fd12ea
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14900138e80000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=10907197680000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0aab25a831ba/disk-30523014.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9d1b7b8fdf8a/vmlinux-30523014.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e9b6822fcd5f/bzImage-30523014.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/82e806de5984/mount_0.gz

The issue was bisected to:

commit 6ed05643ddb166c0fddabac8ee092659006214a9
Author: Boris Burkov <boris@bur.io>
Date:   Wed Jun 28 18:00:05 2023 +0000

    btrfs: create qgroup earlier in snapshot creation

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=117a7050e80000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=137a7050e80000
console output: https://syzkaller.appspot.com/x/log.txt?x=157a7050e80000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4d81015bc10889fd12ea@syzkaller.appspotmail.com
Fixes: 6ed05643ddb1 ("btrfs: create qgroup earlier in snapshot creation")

------------[ cut here ]------------
BTRFS: Transaction aborted (error -17)
WARNING: CPU: 0 PID: 5057 at fs/btrfs/transaction.c:1778 create_pending_snapshot+0x25f4/0x2b70 fs/btrfs/transaction.c:1778
Modules linked in:
CPU: 0 PID: 5057 Comm: syz-executor225 Not tainted 6.6.0-syzkaller-15365-g305230142ae0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
RIP: 0010:create_pending_snapshot+0x25f4/0x2b70 fs/btrfs/transaction.c:1778
Code: f8 fd 48 c7 c7 00 43 ab 8b 89 de e8 76 4b be fd 0f 0b e9 30 f3 ff ff e8 7a 8d f8 fd 48 c7 c7 00 43 ab 8b 89 de e8 5c 4b be fd <0f> 0b e9 f8 f6 ff ff e8 60 8d f8 fd 48 c7 c7 00 43 ab 8b 89 de e8
RSP: 0018:ffffc90003abf580 EFLAGS: 00010246
RAX: 10fb7cf24e10ea00 RBX: 00000000ffffffef RCX: ffff888023ea9dc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003abf870 R08: ffffffff81547c82 R09: 1ffff11017305172
R10: dffffc0000000000 R11: ffffed1017305173 R12: ffff888078ae2878
R13: 00000000ffffffef R14: 0000000000000000 R15: ffff888078ae2818
FS:  000055555667d380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6ff7bf2304 CR3: 0000000079f17000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 create_pending_snapshots+0x195/0x1d0 fs/btrfs/transaction.c:1967
 btrfs_commit_transaction+0xf1c/0x3730 fs/btrfs/transaction.c:2440
 create_snapshot+0x4a5/0x7e0 fs/btrfs/ioctl.c:845
 btrfs_mksubvol+0x5d0/0x750 fs/btrfs/ioctl.c:995
 btrfs_mksnapshot+0xb5/0xf0 fs/btrfs/ioctl.c:1041
 __btrfs_ioctl_snap_create+0x344/0x460 fs/btrfs/ioctl.c:1294
 btrfs_ioctl_snap_create+0x13c/0x190 fs/btrfs/ioctl.c:1321
 btrfs_ioctl+0xbbf/0xd40
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xf8/0x170 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f2f791127b9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 61 17 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc5dc597b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00007f2f791127b9
RDX: 0000000020000a80 RSI: 0000000050009401 RDI: 0000000000000004
RBP: 00007f2f7918b610 R08: 00007ffc5dc59988 R09: 00007ffc5dc59988
R10: 00007ffc5dc59988 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffc5dc59978 R14: 0000000000000001 R15: 0000000000000001
 </TASK>


---
This report is generated by a bot. It may contain errors.
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For information about bisection process see: https://goo.gl/tpsmEJ#bisection

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

If you want to overwrite report's subsystems, reply with:
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If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

Re: [syzbot] [btrfs?] WARNING in create_pending_snapshot

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
WARNING: lock held when returning to user space in btrfs_ioctl_qgroup_create

BTRFS info (device loop0): clearing compat-ro feature flag for FREE_SPACE_TREE (0x1)
BTRFS info (device loop0): clearing compat-ro feature flag for FREE_SPACE_TREE_VALID (0x2)
BTRFS info (device loop0): checking UUID tree
================================================
WARNING: lock held when returning to user space!
6.6.0-syzkaller-15365-g305230142ae0-dirty #0 Not tainted
------------------------------------------------
syz-executor.0/5537 is leaving the kernel with locks still held!
3 locks held by syz-executor.0/5537:
 #0: ffff88806e8a2608 (sb_internal#2){.+.+}-{0:0}, at: btrfs_ioctl_qgroup_create+0x103/0x200 fs/btrfs/ioctl.c:3802
 #1: ffff888052082390 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0x401/0xce0 fs/btrfs/transaction.c:294
 #2: ffff8880520823b8 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0x401/0xce0 fs/btrfs/transaction.c:294


Tested on:

commit:         30523014 Merge tag 'pm-6.7-rc1-2' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=17cb5797680000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=4d81015bc10889fd12ea
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=11c9591f680000

Re: [syzbot] [btrfs?] WARNING in create_pending_snapshot

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+4d81015bc10889fd12ea@syzkaller.appspotmail.com

Tested on:

commit:         30523014 Merge tag 'pm-6.7-rc1-2' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=17929338e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=4d81015bc10889fd12ea
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=10c4f8b7680000

Note: testing is done by a robot and is best-effort only.

Re: [syzbot] [btrfs?] WARNING in create_pending_snapshot

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

fs/btrfs/disk-io.c:4934:9: error: call to undeclared function 'find_qgroup_rb'; ISO C99 and later do not support implicit function declarations [-Werror,-Wimplicit-function-declaration]
fs/btrfs/disk-io.c:4934:61: error: expected ')'


Tested on:

commit:         30523014 Merge tag 'pm-6.7-rc1-2' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=4d81015bc10889fd12ea
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=124c62b7680000

Re: [syzbot] [btrfs?] WARNING in create_pending_snapshot

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

fs/btrfs/disk-io.c:4934:61: error: expected ')'


Tested on:

commit:         30523014 Merge tag 'pm-6.7-rc1-2' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=4d81015bc10889fd12ea
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=16e441ff680000

Re: [syzbot] [btrfs?] WARNING in create_pending_snapshot

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

fs/btrfs/disk-io.c:4934: undefined reference to `find_qgroup_rb'


Tested on:

commit:         30523014 Merge tag 'pm-6.7-rc1-2' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=4d81015bc10889fd12ea
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1263c55b680000

Re: [syzbot] [btrfs?] WARNING in create_pending_snapshot

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

fs/btrfs/disk-io.c:4934: undefined reference to `find_qgroup_rb'


Tested on:

commit:         30523014 Merge tag 'pm-6.7-rc1-2' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=4d81015bc10889fd12ea
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=10a8c3c0e80000

Re: [syzbot] [btrfs?] WARNING in create_pending_snapshot

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

fs/btrfs/qgroup.h:432: multiple definition of `exist_qgroup_rb'; fs/btrfs/super.o:fs/btrfs/qgroup.h:432: first defined here


Tested on:

commit:         30523014 Merge tag 'pm-6.7-rc1-2' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=4d81015bc10889fd12ea
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=17cc7338e80000

Re: [syzbot] [btrfs?] WARNING in create_pending_snapshot

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

fs/btrfs/qgroup.h:433: undefined reference to `find_qgroup_rb'


Tested on:

commit:         30523014 Merge tag 'pm-6.7-rc1-2' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=4d81015bc10889fd12ea
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=11ce1eff680000

Re: [syzbot] [btrfs?] WARNING in create_pending_snapshot

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+4d81015bc10889fd12ea@syzkaller.appspotmail.com

Tested on:

commit:         30523014 Merge tag 'pm-6.7-rc1-2' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=164c7d88e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=4d81015bc10889fd12ea
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=1047e947680000

Note: testing is done by a robot and is best-effort only.

Re: [syzbot] [btrfs?] WARNING in create_pending_snapshot

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+4d81015bc10889fd12ea@syzkaller.appspotmail.com

Tested on:

commit:         30523014 Merge tag 'pm-6.7-rc1-2' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=13fa93e0e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=4d81015bc10889fd12ea
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=13fb5fdf680000

Note: testing is done by a robot and is best-effort only.

Re: [syzbot] [btrfs?] WARNING in create_pending_snapshot

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
BUG: sleeping function called from invalid context in btrfs_get_free_objectid

BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 5526, name: syz-executor.0
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
10 locks held by syz-executor.0/5526:
 #0: ffff8880751f4418 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write_file+0x61/0x200 fs/namespace.c:448
 #1: ffff888073da1818 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: btrfs_mksubvol+0x1c9/0x750 fs/btrfs/ioctl.c:967
 #2: ffff888020974be8 (&fs_info->subvol_sem){++++}-{3:3}, at: btrfs_mksubvol+0x52a/0x750 fs/btrfs/ioctl.c:989
 #3: ffff8880751f4608 (sb_internal#2){.+.+}-{0:0}, at: create_snapshot+0x437/0x7e0 fs/btrfs/ioctl.c:837
 #4: ffff888020976458 (btrfs_trans_completed){.+.+}-{0:0}, at: btrfs_commit_transaction+0x17b/0x3730 fs/btrfs/transaction.c:2214
 #5: ffff888020976430 (btrfs_trans_super_committed){.+.+}-{0:0}, at: btrfs_commit_transaction+0x17b/0x3730 fs/btrfs/transaction.c:2214
 #6: ffff888020976408 (btrfs_trans_unblocked){++++}-{0:0}, at: btrfs_commit_transaction+0x17b/0x3730 fs/btrfs/transaction.c:2214
 #7: ffff888020974cb8 (&fs_info->reloc_mutex){+.+.}-{3:3}, at: btrfs_commit_transaction+0xf14/0x3730 fs/btrfs/transaction.c:2433
 #8: ffff888020975818 (&fs_info->qgroup_ioctl_lock){+.+.}-{3:3}, at: btrfs_create_qgroup+0xa2/0x280 fs/btrfs/qgroup.c:1707
 #9: ffff888020975780 (&fs_info->qgroup_lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
 #9: ffff888020975780 (&fs_info->qgroup_lock){+.+.}-{2:2}, at: btrfs_create_qgroup+0x226/0x280 fs/btrfs/qgroup.c:1729
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 1 PID: 5526 Comm: syz-executor.0 Not tainted 6.6.0-syzkaller-15365-g305230142ae0-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 __might_resched+0x5cf/0x780 kernel/sched/core.c:10151
 __mutex_lock_common kernel/locking/mutex.c:580 [inline]
 __mutex_lock+0xc1/0xd60 kernel/locking/mutex.c:747
 btrfs_get_free_objectid+0x34/0x180 fs/btrfs/disk-io.c:4924
 add_qgroup_rb+0x3a0/0x440 fs/btrfs/qgroup.c:236
 btrfs_create_qgroup+0x234/0x280 fs/btrfs/qgroup.c:1730
 create_pending_snapshot+0x8cc/0x2b70 fs/btrfs/transaction.c:1776
 create_pending_snapshots+0x195/0x1d0 fs/btrfs/transaction.c:1967
 btrfs_commit_transaction+0xf1c/0x3730 fs/btrfs/transaction.c:2440
 create_snapshot+0x4a5/0x7e0 fs/btrfs/ioctl.c:845
 btrfs_mksubvol+0x5d0/0x750 fs/btrfs/ioctl.c:995
 btrfs_mksnapshot+0xb5/0xf0 fs/btrfs/ioctl.c:1041
 __btrfs_ioctl_snap_create+0x344/0x460 fs/btrfs/ioctl.c:1294
 btrfs_ioctl_snap_create+0x13c/0x190 fs/btrfs/ioctl.c:1321
 btrfs_ioctl+0xbbf/0xd40
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xf8/0x170 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f6d5147cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6d5220d0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f6d5159c050 RCX: 00007f6d5147cae9
RDX: 0000000020000a80 RSI: 0000000050009401 RDI: 0000000000000004
RBP: 00007f6d514c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f6d5159c050 R15: 00007ffcea145098
 </TASK>

=============================
[ BUG: Invalid wait context ]
6.6.0-syzkaller-15365-g305230142ae0-dirty #0 Tainted: G        W         
-----------------------------
syz-executor.0/5526 is trying to lock:
ffff8880277522d8 (&root->objectid_mutex){+.+.}-{3:3}, at: btrfs_get_free_objectid+0x34/0x180 fs/btrfs/disk-io.c:4924
other info that might help us debug this:
context-{4:4}
10 locks held by syz-executor.0/5526:
 #0: ffff8880751f4418 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write_file+0x61/0x200 fs/namespace.c:448
 #1: ffff888073da1818 (&type->i_mutex_dir_key#8/1){+.+.}-{3:3}, at: btrfs_mksubvol+0x1c9/0x750 fs/btrfs/ioctl.c:967
 #2: ffff888020974be8 (&fs_info->subvol_sem){++++}-{3:3}, at: btrfs_mksubvol+0x52a/0x750 fs/btrfs/ioctl.c:989
 #3: ffff8880751f4608 (sb_internal#2){.+.+}-{0:0}, at: create_snapshot+0x437/0x7e0 fs/btrfs/ioctl.c:837
 #4: ffff888020976458 (btrfs_trans_completed){.+.+}-{0:0}, at: btrfs_commit_transaction+0x17b/0x3730 fs/btrfs/transaction.c:2214
 #5: ffff888020976430 (btrfs_trans_super_committed){.+.+}-{0:0}, at: btrfs_commit_transaction+0x17b/0x3730 fs/btrfs/transaction.c:2214
 #6: ffff888020976408 (btrfs_trans_unblocked){++++}-{0:0}, at: btrfs_commit_transaction+0x17b/0x3730 fs/btrfs/transaction.c:2214
 #7: ffff888020974cb8 (&fs_info->reloc_mutex){+.+.}-{3:3}, at: btrfs_commit_transaction+0xf14/0x3730 fs/btrfs/transaction.c:2433
 #8: ffff888020975818 (&fs_info->qgroup_ioctl_lock){+.+.}-{3:3}, at: btrfs_create_qgroup+0xa2/0x280 fs/btrfs/qgroup.c:1707
 #9: ffff888020975780 (&fs_info->qgroup_lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
 #9: ffff888020975780 (&fs_info->qgroup_lock){+.+.}-{2:2}, at: btrfs_create_qgroup+0x226/0x280 fs/btrfs/qgroup.c:1729
stack backtrace:
CPU: 1 PID: 5526 Comm: syz-executor.0 Tainted: G        W          6.6.0-syzkaller-15365-g305230142ae0-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 print_lock_invalid_wait_context kernel/locking/lockdep.c:4750 [inline]
 check_wait_context kernel/locking/lockdep.c:4820 [inline]
 __lock_acquire+0x1825/0x7f70 kernel/locking/lockdep.c:5086
 lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5753
 __mutex_lock_common kernel/locking/mutex.c:603 [inline]
 __mutex_lock+0x136/0xd60 kernel/locking/mutex.c:747
 btrfs_get_free_objectid+0x34/0x180 fs/btrfs/disk-io.c:4924
 add_qgroup_rb+0x3a0/0x440 fs/btrfs/qgroup.c:236
 btrfs_create_qgroup+0x234/0x280 fs/btrfs/qgroup.c:1730
 create_pending_snapshot+0x8cc/0x2b70 fs/btrfs/transaction.c:1776
 create_pending_snapshots+0x195/0x1d0 fs/btrfs/transaction.c:1967
 btrfs_commit_transaction+0xf1c/0x3730 fs/btrfs/transaction.c:2440
 create_snapshot+0x4a5/0x7e0 fs/btrfs/ioctl.c:845
 btrfs_mksubvol+0x5d0/0x750 fs/btrfs/ioctl.c:995
 btrfs_mksnapshot+0xb5/0xf0 fs/btrfs/ioctl.c:1041
 __btrfs_ioctl_snap_create+0x344/0x460 fs/btrfs/ioctl.c:1294
 btrfs_ioctl_snap_create+0x13c/0x190 fs/btrfs/ioctl.c:1321
 btrfs_ioctl+0xbbf/0xd40
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xf8/0x170 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f6d5147cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6d5220d0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f6d5159c050 RCX: 00007f6d5147cae9
RDX: 0000000020000a80 RSI: 0000000050009401 RDI: 0000000000000004
RBP: 00007f6d514c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f6d5159c050 R15: 00007ffcea145098
 </TASK>


Tested on:

commit:         30523014 Merge tag 'pm-6.7-rc1-2' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=12c3dc70e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=4d81015bc10889fd12ea
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=122f123f680000

Re: [syzbot] [btrfs?] WARNING in create_pending_snapshot

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
WARNING in create_pending_snapshot

BTRFS info (device loop0): checking UUID tree
------------[ cut here ]------------
BTRFS: Transaction aborted (error -17)
WARNING: CPU: 0 PID: 5480 at fs/btrfs/transaction.c:1778 create_pending_snapshot+0x25f4/0x2b70 fs/btrfs/transaction.c:1778
Modules linked in:
CPU: 0 PID: 5480 Comm: syz-executor.0 Not tainted 6.6.0-syzkaller-15365-g305230142ae0-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
RIP: 0010:create_pending_snapshot+0x25f4/0x2b70 fs/btrfs/transaction.c:1778
Code: f8 fd 48 c7 c7 00 43 ab 8b 89 de e8 76 4b be fd 0f 0b e9 30 f3 ff ff e8 7a 8d f8 fd 48 c7 c7 00 43 ab 8b 89 de e8 5c 4b be fd <0f> 0b e9 f8 f6 ff ff e8 60 8d f8 fd 48 c7 c7 00 43 ab 8b 89 de e8
RSP: 0018:ffffc900094cf580 EFLAGS: 00010246
RAX: ca9849a0d3eb4500 RBX: 00000000ffffffef RCX: ffff88807ac39dc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900094cf870 R08: ffffffff81547c82 R09: 1ffff92001299e04
R10: dffffc0000000000 R11: fffff52001299e05 R12: ffff88807ca30500
R13: 00000000ffffffef R14: 0000000000000000 R15: ffff88807ca304a0
FS:  00007f9af6b8a6c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f15547ad018 CR3: 0000000028d0c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 create_pending_snapshots+0x195/0x1d0 fs/btrfs/transaction.c:1967
 btrfs_commit_transaction+0xf1c/0x3730 fs/btrfs/transaction.c:2440
 create_snapshot+0x4a5/0x7e0 fs/btrfs/ioctl.c:845
 btrfs_mksubvol+0x5d0/0x750 fs/btrfs/ioctl.c:995
 btrfs_mksnapshot+0xb5/0xf0 fs/btrfs/ioctl.c:1041
 __btrfs_ioctl_snap_create+0x344/0x460 fs/btrfs/ioctl.c:1294
 btrfs_ioctl_snap_create+0x13c/0x190 fs/btrfs/ioctl.c:1321
 btrfs_ioctl+0xbbf/0xd40
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xf8/0x170 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f9af5e7cae9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9af6b8a0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f9af5f9bf80 RCX: 00007f9af5e7cae9
RDX: 0000000020000a80 RSI: 0000000050009401 RDI: 0000000000000004
RBP: 00007f9af5ec847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f9af5f9bf80 R15: 00007ffcf277e6d8
 </TASK>


Tested on:

commit:         30523014 Merge tag 'pm-6.7-rc1-2' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=112cafc4e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=4d81015bc10889fd12ea
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=15c3dc70e80000

Re: [syzbot] [btrfs?] WARNING in create_pending_snapshot

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+4d81015bc10889fd12ea@syzkaller.appspotmail.com

Tested on:

commit:         30523014 Merge tag 'pm-6.7-rc1-2' of git://git.kernel...
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=17aced04e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=beb32a598fd79db9
dashboard link: https://syzkaller.appspot.com/bug?extid=4d81015bc10889fd12ea
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=12185f38e80000

Note: testing is done by a robot and is best-effort only.