[syzbot] [bcachefs?] WARNING in bch2_trans_srcu_unlock

[syzbot <syzbot+1e515cab343dbe5aa38a@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    f03359bca01b Merge tag 'for-6.9-rc6-tag' of git://git.kern..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13f82450980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d2f00edef461175
dashboard link: https://syzkaller.appspot.com/bug?extid=1e515cab343dbe5aa38a
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e3ee5200440e/disk-f03359bc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/c651e70b4ae3/vmlinux-f03359bc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/196f43b316ad/bzImage-f03359bc.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1e515cab343dbe5aa38a@syzkaller.appspotmail.com

------------[ cut here ]------------
btree trans held srcu lock (delaying memory reclaim) for 28 seconds
WARNING: CPU: 1 PID: 5195 at fs/bcachefs/btree_iter.c:2873 check_srcu_held_too_long fs/bcachefs/btree_iter.c:2871 [inline]
WARNING: CPU: 1 PID: 5195 at fs/bcachefs/btree_iter.c:2873 bch2_trans_srcu_unlock+0x4f1/0x600 fs/bcachefs/btree_iter.c:2887
Modules linked in:
CPU: 1 PID: 5195 Comm: syz-executor.1 Not tainted 6.9.0-rc6-syzkaller-00131-gf03359bca01b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
RIP: 0010:check_srcu_held_too_long fs/bcachefs/btree_iter.c:2871 [inline]
RIP: 0010:bch2_trans_srcu_unlock+0x4f1/0x600 fs/bcachefs/btree_iter.c:2887
Code: 2b 1f 48 c1 eb 02 48 b9 c3 f5 28 5c 8f c2 f5 28 48 89 d8 48 f7 e1 48 c1 ea 02 48 c7 c7 40 26 11 8c 48 89 d6 e8 e0 a5 49 fd 90 <0f> 0b 90 90 e9 c0 fe ff ff 44 89 f9 80 e1 07 38 c1 0f 8c 38 fb ff
RSP: 0018:ffffc900042ff1b0 EFLAGS: 00010246
RAX: e963e25abba3d100 RBX: 00000000000002c5 RCX: 0000000000040000
RDX: ffffc9000ade7000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: 00000000ffffaff9 R08: ffffffff81588e32 R09: 1ffff110172a519a
R10: dffffc0000000000 R11: ffffed10172a519b R12: dffffc0000000000
R13: 1ffff1100fe0000d R14: 1ffff1100fe00008 R15: ffff88807f000068
FS:  00007f85a17656c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5df13ff000 CR3: 000000007841e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 bch2_trans_begin+0x1482/0x1920 fs/bcachefs/btree_iter.c:2963
 __bchfs_fallocate fs/bcachefs/fs-io.c:608 [inline]
 bchfs_fallocate fs/bcachefs/fs-io.c:733 [inline]
 bch2_fallocate_dispatch+0x1181/0x3810 fs/bcachefs/fs-io.c:780
 vfs_fallocate+0x564/0x6c0 fs/open.c:330
 do_vfs_ioctl+0x2592/0x2e50 fs/ioctl.c:883
 __do_sys_ioctl fs/ioctl.c:902 [inline]
 __se_sys_ioctl+0x81/0x170 fs/ioctl.c:890
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f85a0a7dd29
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:00007f85a17650c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f85a0babf80 RCX: 00007f85a0a7dd29
RDX: 0000000020000000 RSI: 0000000040305828 RDI: 000000000000000a
RBP: 00007f85a0aca47e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f85a0babf80 R15: 00007fff348b2c78
 </TASK>


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