=============================
[ BUG: Invalid wait context ]
6.15.0-syzkaller-08486-gf66bc387efbe #0 Not tainted
-----------------------------
syz.1.168/6576 is trying to lock:
ffffc90007ef2410 (&gpc->lock){....}-{3:3}, at: kvm_xen_set_evtchn_fast+0x254/0xeb0 arch/x86/kvm/xen.c:1819
other info that might help us debug this:
context-{2:2}
4 locks held by syz.1.168/6576:
#0: ffff88802563d7e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:129 [inline]
#0: ffff88802563d7e0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x1f9/0xb90 mm/mmap.c:1292
#1: ffff8880348655b8 (&anon_vma->rwsem){++++}-{4:4}, at: lock_anon_vma_root mm/rmap.c:250 [inline]
#1: ffff8880348655b8 (&anon_vma->rwsem){++++}-{4:4}, at: unlink_anon_vmas+0x201/0x820 mm/rmap.c:408
#2: ffffffff8e3c4780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#2: ffffffff8e3c4780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#2: ffffffff8e3c4780 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
#2: ffffffff8e3c4780 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x20a0 arch/x86/kernel/unwind_orc.c:479
#3: ffffc90007ef2960 (&kvm->srcu){.?.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#3: ffffc90007ef2960 (&kvm->srcu){.?.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#3: ffffc90007ef2960 (&kvm->srcu){.?.+}-{0:0}, at: kvm_xen_set_evtchn_fast+0x23a/0xeb0 arch/x86/kvm/xen.c:1817
stack backtrace:
CPU: 0 UID: 0 PID: 6576 Comm: syz.1.168 Not tainted 6.15.0-syzkaller-08486-gf66bc387efbe #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
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:4833 [inline]
check_wait_context kernel/locking/lockdep.c:4905 [inline]
__lock_acquire+0xa12/0x1c90 kernel/locking/lockdep.c:5190
lock_acquire kernel/locking/lockdep.c:5871 [inline]
lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5828
__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:1819
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+0x108/0x3f0 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:5875
Code: 98 12 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 92 1d ef 0e 0f 82 74 02 00 00 8b 35 7a 4f ef 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 29 98 12 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc90006e77350 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3c4780 RCX: 000000004ac9e0fe
RDX: 0000000000000000 RSI: ffffffff8dbe196c RDI: ffffffff8bf52fc0
RBP: 0000000000000002 R08: 7e3bb79592184c44 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
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+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2380 [inline]
slab_free mm/slub.c:4642 [inline]
kmem_cache_free+0x2d1/0x4d0 mm/slub.c:4744
anon_vma_chain_free mm/rmap.c:147 [inline]
unlink_anon_vmas+0x173/0x820 mm/rmap.c:421
free_pgtables+0x2d4/0x810 mm/memory.c:391
exit_mmap+0x3fb/0xb90 mm/mmap.c:1295
__mmput+0x12a/0x410 kernel/fork.c:1381
mmput+0x62/0x70 kernel/fork.c:1404
exit_mm kernel/exit.c:595 [inline]
do_exit+0xa3a/0x2c70 kernel/exit.c:947
do_group_exit+0xd3/0x2a0 kernel/exit.c:1108
get_signal+0x2673/0x26d0 kernel/signal.c:3034
arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:111
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f726138e969
Code: Unable to access opcode bytes at 0x7f726138e93f.
RSP: 002b:00007f726223c0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f72615b6248 RCX: 00007f726138e969
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f72615b6248
RBP: 00007f72615b6240 R08: 00007ffc5b742717 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f72615b624c
R13: 0000000000000001 R14: 00007ffc5b742630 R15: 00007ffc5b742718
vkms_vblank_simulate: vblank timer overrun
----------------
Code disassembly (best guess):
0: 98 cwtl
1: 12 12 adc (%rdx),%dl
3: 83 f8 07 cmp $0x7,%eax
6: 0f 87 bc 02 00 00 ja 0x2c8
c: 89 c0 mov %eax,%eax
e: 48 0f a3 05 92 1d ef bt %rax,0xeef1d92(%rip) # 0xeef1da8
15: 0e
16: 0f 82 74 02 00 00 jb 0x290
1c: 8b 35 7a 4f ef 0e mov 0xeef4f7a(%rip),%esi # 0xeef4f9c
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 29 98 12 sub %gs:0x12129829(%rip),%rax # 0x12129860
36: 12
37: 0f 85 c7 02 00 00 jne 0x304
3d: 48 rex.W
3e: 83 .byte 0x83
3f: c4 .byte 0xc4