============================= [ BUG: Invalid wait context ] 6.16.0-next-20250808-syzkaller #0 Not tainted ----------------------------- syz.1.1389/10688 is trying to lock: ffff888059f15410 (&gpc->lock){....}-{3:3}, at: kvm_xen_set_evtchn_fast+0x1fb/0x9b0 arch/x86/kvm/xen.c:1820 other info that might help us debug this: context-{2:2} 3 locks held by syz.1.1389/10688: #0: ffff88807bc72220 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:453 [inline] #0: ffff88807bc72220 (&mm->mmap_lock){++++}-{4:4}, at: __mm_populate+0x16f/0x380 mm/gup.c:1962 #1: ffffffff8e539ee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #1: ffffffff8e539ee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #1: ffffffff8e539ee0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1155 [inline] #1: ffffffff8e539ee0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa5/0x2390 arch/x86/kernel/unwind_orc.c:479 #2: ffff888059f15960 (&kvm->srcu){.?.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #2: ffff888059f15960 (&kvm->srcu){.?.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #2: ffff888059f15960 (&kvm->srcu){.?.+}-{0:0}, at: kvm_xen_set_evtchn_fast+0x1c3/0x9b0 arch/x86/kvm/xen.c:1818 stack backtrace: CPU: 0 UID: 0 PID: 10688 Comm: syz.1.1389 Not tainted 6.16.0-next-20250808-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x189/0x250 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+0xbcb/0xd20 kernel/locking/lockdep.c:5187 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:160 [inline] _raw_read_lock_irqsave+0xaf/0x100 kernel/locking/spinlock.c:236 kvm_xen_set_evtchn_fast+0x1fb/0x9b0 arch/x86/kvm/xen.c:1820 xen_timer_callback+0x109/0x220 arch/x86/kvm/xen.c:140 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x4e0/0xc60 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1056 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 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+0x175/0x360 kernel/locking/lockdep.c:5872 Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 9b a2 46 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc9000b7cee38 EFLAGS: 00000206 RAX: c05dbdc936d19800 RBX: 0000000000000000 RCX: c05dbdc936d19800 RDX: 0000000000000000 RSI: ffffffff8de84cf9 RDI: ffffffff8c04d480 RBP: ffffffff81731195 R08: 0000000000000000 R09: ffffffff81731195 R10: ffffc9000b7ceff8 R11: ffffffff81ac90a0 R12: 0000000000000002 R13: ffffffff8e539ee0 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf5/0x1f0 mm/page_owner.c:156 __set_page_owner+0x8d/0x4a0 mm/page_owner.c:329 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 folio_alloc_mpol_noprof mm/mempolicy.c:2435 [inline] vma_alloc_folio_noprof+0xe4/0x200 mm/mempolicy.c:2470 folio_prealloc+0x30/0x180 mm/memory.c:-1 do_cow_fault mm/memory.c:5597 [inline] do_fault mm/memory.c:5709 [inline] do_pte_missing mm/memory.c:4234 [inline] handle_pte_fault mm/memory.c:6052 [inline] __handle_mm_fault+0x16fd/0x5440 mm/memory.c:6195 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6364 faultin_page mm/gup.c:1144 [inline] __get_user_pages+0x1699/0x2ce0 mm/gup.c:1446 populate_vma_page_range+0x29f/0x3a0 mm/gup.c:1880 __mm_populate+0x24c/0x380 mm/gup.c:1983 mm_populate include/linux/mm.h:3374 [inline] vm_mmap_pgoff+0x387/0x4d0 mm/util.c:585 ksys_mmap_pgoff+0x51f/0x760 mm/mmap.c:604 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff03af8ebe9 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:00007ff03bd9c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007ff03b1b6090 RCX: 00007ff03af8ebe9 RDX: 0000000003000003 RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007ff03b011e19 R08: 0000000000000003 R09: 00000000a471a000 R10: 0000000000022052 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff03b1b6128 R14: 00007ff03b1b6090 R15: 00007ffdaf194058 ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 00 00 add %al,(%rax) 4: 9c pushf 5: 8f 44 24 30 pop 0x30(%rsp) 9: f7 44 24 30 00 02 00 testl $0x200,0x30(%rsp) 10: 00 11: 0f 85 cd 00 00 00 jne 0xe4 17: f7 44 24 08 00 02 00 testl $0x200,0x8(%rsp) 1e: 00 1f: 74 01 je 0x22 21: fb sti 22: 65 48 8b 05 9b a2 46 mov %gs:0x1146a29b(%rip),%rax # 0x1146a2c5 29: 11 * 2a: 48 3b 44 24 58 cmp 0x58(%rsp),%rax <-- trapping instruction 2f: 0f 85 f2 00 00 00 jne 0x127 35: 48 83 c4 60 add $0x60,%rsp 39: 5b pop %rbx 3a: 41 5c pop %r12 3c: 41 5d pop %r13 3e: 41 5e pop %r14