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truncate spotted in mem i_size < btree i_size: 55490 < 57344
WARNING: CPU: 0 PID: 7767 at fs/bcachefs/fs-io.c:472 bchfs_truncate+0x88c/0xa70 fs/bcachefs/fs-io.c:469
Modules linked in:
CPU: 0 UID: 0 PID: 7767 Comm: syz.0.194 Not tainted 6.15.0-rc7-syzkaller-gd7fa1af5b33e #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : bchfs_truncate+0x88c/0xa70 fs/bcachefs/fs-io.c:469
lr : bchfs_truncate+0x88c/0xa70 fs/bcachefs/fs-io.c:469
sp : ffff8000a0597300
x29: ffff8000a0597590 x28: 000000000000e000 x27: ffff000102128030
x26: ffff0001021284a8 x25: ffff8000a0597710 x24: ffff7000140b2e70
x23: 000000000000d8c2 x22: ffff000102128568 x21: ffff0001021284a0
x20: dfff800000000000 x19: ffff000102128000 x18: 00000000ffffffff
x17: 0000000000000000 x16: ffff80008ad27e48 x15: ffff700011e740c0
x14: 1ffff00011e740c0 x13: 0000000000000004 x12: ffffffffffffffff
x11: ffff700011e740c0 x10: 0000000000ff0100 x9 : c85c2422f47d6100
x8 : c85c2422f47d6100 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff8000a0596c58 x4 : ffff80008f415ba0 x3 : ffff800080548ef0
x2 : 0000000000000000 x1 : 0000000100000000 x0 : 0000000000000000
Call trace:
 bchfs_truncate+0x88c/0xa70 fs/bcachefs/fs-io.c:469 (P)
 bch2_setattr+0x198/0x20c fs/bcachefs/fs.c:1245
 notify_change+0x9a4/0xc50 fs/attr.c:552
 do_truncate+0x178/0x1f0 fs/open.c:65
 handle_truncate fs/namei.c:3501 [inline]
 do_open fs/namei.c:3884 [inline]
 path_openat+0x25a0/0x2c40 fs/namei.c:4039
 do_filp_open+0x18c/0x36c fs/namei.c:4066
 do_sys_openat2+0x11c/0x1b4 fs/open.c:1429
 do_sys_open fs/open.c:1444 [inline]
 __do_sys_openat fs/open.c:1460 [inline]
 __se_sys_openat fs/open.c:1455 [inline]
 __arm64_sys_openat+0x120/0x158 fs/open.c:1455
 __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+0x58/0x17c arch/arm64/kernel/entry-common.c:767
 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
irq event stamp: 71382
hardirqs last  enabled at (71381): [<ffff80008055041c>] __up_console_sem kernel/printk/printk.c:344 [inline]
hardirqs last  enabled at (71381): [<ffff80008055041c>] __console_unlock+0x70/0xc4 kernel/printk/printk.c:2885
hardirqs last disabled at (71382): [<ffff80008adb9eb8>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:511
softirqs last  enabled at (71272): [<ffff8000801fbf10>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (71270): [<ffff8000801fbedc>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
---[ end trace 0000000000000000 ]---