=============================
[ BUG: Invalid wait context ]
syzkaller #0 Not tainted
-----------------------------
syz.0.245/6983 is trying to lock:
ffff8880748ad410 (&gpc->lock){....}-{3:3}, at: kvm_xen_set_evtchn_fast+0x254/0xeb0 arch/x86/kvm/xen.c:1820
other info that might help us debug this:
context-{2:2}
5 locks held by syz.0.245/6983:
#0: ffff8880792c4260 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:415 [inline]
#0: ffff8880792c4260 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1f5/0x470 mm/util.c:578
#1: ffffffff8e5c1260 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#1: ffffffff8e5c1260 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#1: ffffffff8e5c1260 (rcu_read_lock){....}-{1:3}, at: ___pte_offset_map+0x33/0x4f0 mm/pgtable-generic.c:286
#2: ffff88803271e858 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
#2: ffff88803271e858 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: __pte_offset_map_lock+0x10f/0x310 mm/pgtable-generic.c:401
#3: ffffffff8e5c11a0 (rcu_read_lock_sched){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#3: ffffffff8e5c11a0 (rcu_read_lock_sched){....}-{1:2}, at: rcu_read_lock_sched include/linux/rcupdate.h:932 [inline]
#3: ffffffff8e5c11a0 (rcu_read_lock_sched){....}-{1:2}, at: pfn_valid+0x140/0x4d0 include/linux/mmzone.h:2162
#4: ffff8880748ad960 (&kvm->srcu){.?.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#4: ffff8880748ad960 (&kvm->srcu){.?.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#4: ffff8880748ad960 (&kvm->srcu){.?.+}-{0:0}, at: kvm_xen_set_evtchn_fast+0x23a/0xeb0 arch/x86/kvm/xen.c:1818
stack backtrace:
CPU: 1 UID: 0 PID: 6983 Comm: syz.0.245 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_lock_invalid_wait_context kernel/locking/lockdep.c:4830 [inline]
check_wait_context kernel/locking/lockdep.c:4902 [inline]
__lock_acquire+0xa27/0x1ce0 kernel/locking/lockdep.c:5187
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5825
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline]
_raw_read_lock_irqsave+0x46/0x90 kernel/locking/spinlock.c:236
kvm_xen_set_evtchn_fast+0x254/0xeb0 arch/x86/kvm/xen.c:1820
xen_timer_callback+0x1db/0x2a0 arch/x86/kvm/xen.c:140
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x5ed/0xad0 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x3f0 arch/x86/kernel/apic/apic.c:1056
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5872
Code: e6 3e 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 22 a2 13 0f 0f 82 74 02 00 00 8b 35 da d3 13 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 79 e6 3e 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc9000bbd71a8 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e5c11a0 RCX: 0000000090a31473
RDX: 0000000000000000 RSI: ffffffff8de2cdc0 RDI: ffffffff8c162d80
RBP: 0000000000000002 R08: f69d9b0ed8cdb25f R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock_sched include/linux/rcupdate.h:932 [inline]
pfn_valid+0x15c/0x4d0 include/linux/mmzone.h:2162
page_table_check_clear+0x21/0x740 mm/page_table_check.c:70
__page_table_check_pte_clear+0xf1/0x100 mm/page_table_check.c:154
page_table_check_pte_clear include/linux/page_table_check.h:51 [inline]
ptep_get_and_clear arch/x86/include/asm/pgtable.h:1254 [inline]
ptep_get_and_clear_full arch/x86/include/asm/pgtable.h:1272 [inline]
get_and_clear_full_ptes include/linux/pgtable.h:725 [inline]
zap_present_folio_ptes mm/memory.c:1499 [inline]
zap_present_ptes mm/memory.c:1581 [inline]
do_zap_pte_range mm/memory.c:1682 [inline]
zap_pte_range mm/memory.c:1726 [inline]
zap_pmd_range mm/memory.c:1818 [inline]
zap_pud_range mm/memory.c:1847 [inline]
zap_p4d_range mm/memory.c:1868 [inline]
unmap_page_range+0x1e6d/0x42c0 mm/memory.c:1889
unmap_single_vma.constprop.0+0x153/0x240 mm/memory.c:1932
unmap_vmas+0x218/0x470 mm/memory.c:1976
vms_clear_ptes+0x41f/0x770 mm/vma.c:1228
vms_clean_up_area mm/vma.c:1247 [inline]
__mmap_prepare mm/vma.c:2396 [inline]
__mmap_region+0x5e1/0x27b0 mm/vma.c:2651
mmap_region+0x1ab/0x3f0 mm/vma.c:2739
do_mmap+0xa3e/0x1210 mm/mmap.c:558
vm_mmap_pgoff+0x29e/0x470 mm/util.c:580
ksys_mmap_pgoff+0x7d/0x5c0 mm/mmap.c:604
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
__x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f350e78ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f350f673038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f350e9c6270 RCX: 00007f350e78ebe9
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f350e811e19 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f350e9c6308 R14: 00007f350e9c6270 R15: 00007ffda71f3498
----------------
Code disassembly (best guess):
0: e6 3e out %al,$0x3e
2: 12 83 f8 07 0f 87 adc -0x78f0f808(%rbx),%al
8: bc 02 00 00 89 mov $0x89000002,%esp
d: c0 48 0f a3 rorb $0xa3,0xf(%rax)
11: 05 22 a2 13 0f add $0xf13a222,%eax
16: 0f 82 74 02 00 00 jb 0x290
1c: 8b 35 da d3 13 0f mov 0xf13d3da(%rip),%esi # 0xf13d3fc
22: 85 f6 test %esi,%esi
24: 0f 85 8d 00 00 00 jne 0xb7
* 2a: 48 8b 44 24 30 mov 0x30(%rsp),%rax <-- trapping instruction
2f: 65 48 2b 05 79 e6 3e sub %gs:0x123ee679(%rip),%rax # 0x123ee6b0
36: 12
37: 0f 85 c7 02 00 00 jne 0x304
3d: 48 rex.W
3e: 83 .byte 0x83
3f: c4 .byte 0xc4