[syzbot] [btrfs?] WARNING in btrfs_use_block_rsv

syzbot
2023-08-30T22:30:08Z

Hello,

syzbot found the following issue on:

HEAD commit: 3b35375f19fe Merge tag 'irq-urgent-2023-08-26' of git://gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1156791fa80000
kernel config: https://syzkaller.appspot.com/x/.config?x=67db137b0441ab96
dashboard link: https://syzkaller.appspot.com/bug?extid=10d5b62a8d7046b86d22
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1767c1e0680000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=146903b0680000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-3b35375f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/34c4f640b690/vmlinux-3b35375f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/58c9c2459f41/bzImage-3b35375f.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/501d7ead33fe/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+10d5b62a8d7046b86d22@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 5212 at fs/btrfs/block-rsv.c:515 btrfs_use_block_rsv+0x688/0x7f0 fs/btrfs/block-rsv.c:515
Modules linked in:
CPU: 1 PID: 5212 Comm: kworker/u17:1 Not tainted 6.5.0-rc7-syzkaller-00182-g3b35375f19fe #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: btrfs-endio-write btrfs_work_helper
RIP: 0010:btrfs_use_block_rsv+0x688/0x7f0 fs/btrfs/block-rsv.c:515
Code: 89 ea 83 e2 07 38 d0 7f 0c 84 c0 74 08 48 89 ef e8 ed 42 47 fe 0f b6 73 5a ba e4 ff ff ff 48 c7 c7 00 e4 b7 8a e8 b8 b8 ba fd <0f> 0b e9 a3 fd ff ff e8 8c f7 f3 fd 49 8d 9d 80 04 00 00 e9 1c fb
RSP: 0018:ffffc90003737030 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff8880323ba608 RCX: 0000000000000000
RDX: ffff888029a1c4c0 RSI: ffffffff814be3c6 RDI: 0000000000000001
RBP: ffff8880323ba662 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 000000002d2d2d2d R12: 0000000000001000
R13: ffff88801fb84000 R14: 0000000000000001 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff88806b700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020d41000 CR3: 00000000219e2000 CR4: 0000000000350ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
btrfs_alloc_tree_block+0x1dd/0x1420 fs/btrfs/extent-tree.c:4883
__btrfs_cow_block+0x3ce/0x18e0 fs/btrfs/ctree.c:546
btrfs_cow_block+0x2f1/0x820 fs/btrfs/ctree.c:712
btrfs_search_slot+0x12a0/0x30e0 fs/btrfs/ctree.c:2194
btrfs_lookup_file_extent+0xcb/0x110 fs/btrfs/file-item.c:270
btrfs_drop_extents+0x433/0x2bd0 fs/btrfs/file.c:250
insert_reserved_file_extent+0x3a8/0x940 fs/btrfs/inode.c:3057
insert_ordered_extent_file_extent fs/btrfs/inode.c:3164 [inline]
btrfs_finish_one_ordered+0x1443/0x2240 fs/btrfs/inode.c:3268
btrfs_work_helper+0x20b/0xba0 fs/btrfs/async-thread.c:314
process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2600
worker_thread+0x687/0x1110 kernel/workqueue.c:2751
kthread+0x33a/0x430 kernel/kthread.c:389
ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
</TASK>

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