syzbot

watchdog: BUG: soft lockup - CPU#1 stuck for 23s! [syz.0.563:8489]
Modules linked in:
irq event stamp: 251614
hardirqs last  enabled at (251613): [<ffff80008b028df8>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline]
hardirqs last  enabled at (251613): [<ffff80008b028df8>] _raw_spin_unlock_irqrestore+0x38/0x98 kernel/locking/spinlock.c:194
hardirqs last disabled at (251614): [<ffff80008b001cbc>] __el1_irq arch/arm64/kernel/entry-common.c:650 [inline]
hardirqs last disabled at (251614): [<ffff80008b001cbc>] el1_interrupt+0x24/0x54 arch/arm64/kernel/entry-common.c:668
softirqs last  enabled at (251590): [<ffff8000803d88a0>] softirq_handle_end kernel/softirq.c:425 [inline]
softirqs last  enabled at (251590): [<ffff8000803d88a0>] handle_softirqs+0xaf8/0xc88 kernel/softirq.c:607
softirqs last disabled at (251581): [<ffff800080022028>] __do_softirq+0x14/0x20 kernel/softirq.c:613
CPU: 1 UID: 0 PID: 8489 Comm: syz.0.563 Not tainted 6.17.0-rc1-syzkaller-g8f5ae30d69d7 #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : skip_mnt_tree fs/namespace.c:-1 [inline]
pc : commit_tree fs/namespace.c:1201 [inline]
pc : attach_recursive_mnt+0x1414/0x19f0 fs/namespace.c:2716
lr : skip_mnt_tree fs/namespace.c:1184 [inline]
lr : commit_tree fs/namespace.c:1201 [inline]
lr : attach_recursive_mnt+0x1430/0x19f0 fs/namespace.c:2716
sp : ffff8000a0de7960
x29: ffff8000a0de7a60 x28: ffff0000df3956c0 x27: dfff800000000000
x26: ffff0000d65d31c0 x25: ffff0000d65d3180 x24: ffff0000d931d600
x23: ffff0000df3956c0 x22: ffff0000df395500 x21: ffff0000d65d2e41
x20: ffff0000f39e5ab0 x19: ffff0000f39e5ab0 x18: 1fffe000337a0688
x17: ffff0001fea8c8b0 x16: ffff80008afd3190 x15: 0000000000000002
x14: 1fffe0001be72ae1 x13: 0000000000000000 x12: 0000000000000000
x11: ffff60001be72ae3 x10: 0000000000ff0100 x9 : 0000000000000000
x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000
x5 : 0000000000000001 x4 : 0000000000000008 x3 : 0000000000000000
x2 : 0000000000000008 x1 : ffff0000d65d31c0 x0 : ffff0000f39e5aa8
Call trace:
 skip_mnt_tree fs/namespace.c:-1 [inline] (P)
 commit_tree fs/namespace.c:1201 [inline] (P)
 attach_recursive_mnt+0x1414/0x19f0 fs/namespace.c:2716 (P)
 graft_tree+0x134/0x184 fs/namespace.c:2862
 do_loopback+0x334/0x3e8 fs/namespace.c:3037
 path_mount+0x4cc/0xde0 fs/namespace.c:4114
 do_mount fs/namespace.c:4133 [inline]
 __do_sys_mount fs/namespace.c:4344 [inline]
 __se_sys_mount fs/namespace.c:4321 [inline]
 __arm64_sys_mount+0x3e8/0x468 fs/namespace.c:4321
 __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+0x58/0x180 arch/arm64/kernel/entry-common.c:879
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6164 Comm: udevd Not tainted 6.17.0-rc1-syzkaller-g8f5ae30d69d7 #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : __sanitizer_cov_trace_pc+0x80/0x84 kernel/kcov.c:235
lr : path_init+0xdc0/0xe98 fs/namei.c:2537
sp : ffff8000a43e7740
x29: ffff8000a43e77a0 x28: dfff800000000000 x27: 1fffe00018f95664
x26: ffff0000c7cab320 x25: 0000000000000101 x24: 1ffff0001487cf5b
x23: ffff80008f745840 x22: ffff8000a43e7adc x21: 0000000000000100
x20: ffff8000a43e7aa0 x19: 0000000000032fab x18: 0000000000000000
x17: 0000000000000000 x16: ffff80008b007230 x15: 0000000000000001
x14: 1ffff00011ee8b08 x13: 0000000000000000 x12: 0000000000000000
x11: ffff700011ee8b09 x10: 0000000000ff0100 x9 : 0000000000000000
x8 : ffff0000d8babd00 x7 : ffff800080daa4c4 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff800080da8a84
x2 : 0000000000000000 x1 : 0000000000000004 x0 : 0000000000000001
Call trace:
 __sanitizer_cov_trace_pc+0x80/0x84 kernel/kcov.c:235 (P)
 path_openat+0x13c/0x2c40 fs/namei.c:4041
 do_filp_open+0x18c/0x36c fs/namei.c:4073
 do_sys_openat2+0x11c/0x1b4 fs/open.c:1435
 do_sys_open fs/open.c:1450 [inline]
 __do_sys_openat fs/open.c:1466 [inline]
 __se_sys_openat fs/open.c:1461 [inline]
 __arm64_sys_openat+0x120/0x158 fs/open.c:1461
 __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+0x58/0x180 arch/arm64/kernel/entry-common.c:879
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596