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truncate spotted in mem i_size < btree i_size: 10 < 1048576
WARNING: CPU: 0 PID: 8317 at fs/bcachefs/fs-io.c:457 bchfs_truncate+0x8a0/0x990 fs/bcachefs/fs-io.c:454
Modules linked in:
CPU: 0 UID: 0 PID: 8317 Comm: syz.0.258 Not tainted 6.15.0-rc4-syzkaller-ge0f4c8dd9d2d #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : bchfs_truncate+0x8a0/0x990 fs/bcachefs/fs-io.c:454
lr : bchfs_truncate+0x8a0/0x990 fs/bcachefs/fs-io.c:454
sp : ffff80009d437740
x29: ffff80009d437950 x28: 0000000000100000 x27: ffff0000db210f60
x26: ffff0000db2113d8 x25: ffff0000f7ac95c0 x24: ffff700013a86ef8
x23: 000000000000000a x22: ffff0000db211498 x21: ffff0000db2113d0
x20: dfff800000000000 x19: ffff0000db210f30 x18: 00000000ffffffff
x17: 0000000000000000 x16: ffff80008ad0f308 x15: ffff700011e6ff40
x14: 1ffff00011e6ff40 x13: 0000000000000004 x12: ffffffffffffffff
x11: ffff700011e6ff40 x10: 0000000000ff0100 x9 : 31bdfdba4e5cd100
x8 : 31bdfdba4e5cd100 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff80009d437098 x4 : ffff80008f3f4fa0 x3 : ffff80008053fd64
x2 : 0000000000000000 x1 : 0000000100000000 x0 : 0000000000000000
Call trace:
 bchfs_truncate+0x8a0/0x990 fs/bcachefs/fs-io.c:454 (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
 vfs_truncate+0x398/0x444 fs/open.c:115
 do_sys_truncate+0xe4/0x1a8 fs/open.c:138
 __do_sys_truncate fs/open.c:150 [inline]
 __se_sys_truncate fs/open.c:148 [inline]
 __arm64_sys_truncate+0x5c/0x74 fs/open.c:148
 __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+0x58/0x150 arch/arm64/kernel/entry-common.c:744
 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:762
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
irq event stamp: 320
hardirqs last  enabled at (319): [<ffff800080547290>] __up_console_sem kernel/printk/printk.c:344 [inline]
hardirqs last  enabled at (319): [<ffff800080547290>] __console_unlock+0x70/0xc4 kernel/printk/printk.c:2885
hardirqs last disabled at (320): [<ffff80008ada1368>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:488
softirqs last  enabled at (228): [<ffff8000801fa7b0>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (226): [<ffff8000801fa77c>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
---[ end trace 0000000000000000 ]---