============================= [ BUG: Invalid wait context ] syzkaller #0 Not tainted ----------------------------- syz.0.0/5320 is trying to lock: ffff88804f301bb0 (&gpc->lock){....}-{3:3}, at: kvm_xen_set_evtchn_fast+0x1f4/0x9a0 arch/x86/kvm/xen.c:1822 other info that might help us debug this: context-{2:2} 3 locks held by syz.0.0/5320: #0: ffff888036bc00d8 (&type->s_umount_key#51/1){+.+.}-{4:4}, at: alloc_super fs/super.c:345 [inline] #0: ffff888036bc00d8 (&type->s_umount_key#51/1){+.+.}-{4:4}, at: sget_fc+0x938/0x1900 fs/super.c:766 #1: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #1: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline] #1: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1183 [inline] #1: ffffffff8eb59c60 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550 arch/x86/kernel/unwind_orc.c:495 #2: ffff88804f302110 (&kvm->srcu){.?.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:187 [inline] #2: ffff88804f302110 (&kvm->srcu){.?.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:294 [inline] #2: ffff88804f302110 (&kvm->srcu){.?.+}-{0:0}, at: kvm_xen_set_evtchn_fast+0x1bc/0x9a0 arch/x86/kvm/xen.c:1820 stack backtrace: CPU: 0 UID: 0 PID: 5320 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: dump_stack_lvl+0xe8/0x150 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+0xe39/0x2cf0 kernel/locking/lockdep.c:5187 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868 __raw_read_lock_irqsave include/linux/rwlock_api_smp.h:174 [inline] _raw_read_lock_irqsave+0x48/0x60 kernel/locking/spinlock.c:240 kvm_xen_set_evtchn_fast+0x1f4/0x9a0 arch/x86/kvm/xen.c:1822 xen_timer_callback+0x109/0x220 arch/x86/kvm/xen.c:140 __run_hrtimer kernel/time/hrtimer.c:2032 [inline] __hrtimer_run_queues+0x371/0xa10 kernel/time/hrtimer.c:2096 hrtimer_interrupt+0x448/0x910 kernel/time/hrtimer.c:2215 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline] __sysvec_apic_timer_interrupt+0x102/0x430 arch/x86/kernel/apic/apic.c:1068 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:unwind_next_frame+0xae5/0x2550 arch/x86/kernel/unwind_orc.c:610 Code: 48 85 ff 0f 84 b9 0d 00 00 48 83 c7 70 e8 c3 25 00 00 49 89 c0 48 8b 54 24 08 48 8d 5a 01 48 8b 44 24 30 42 0f b6 04 20 84 c0 <4c> 89 04 24 0f 85 26 14 00 00 48 89 dd 48 c1 ed 03 42 0f b6 44 25 RSP: 0018:ffffc9000ecbf5a0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffffff91255037 RCX: ffffffff9095303c RDX: ffffffff91255036 RSI: ffffffff91255032 RDI: ffffffff8c4bce20 RBP: ffffc9000ecbf680 R08: ffffc9000ecbfb80 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff8eb59c60 R12: dffffc0000000000 R13: ffffffff91255032 R14: ffffc9000ecbf648 R15: 1ffff92001d97ec9 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4584 [inline] slab_alloc_node mm/slub.c:4917 [inline] kmem_cache_alloc_noprof+0x2a0/0x5f0 mm/slub.c:4931 alloc_empty_file_noaccount fs/file_table.c:296 [inline] alloc_file_pseudo_noaccount+0x11f/0x2b0 fs/file_table.c:455 bdev_file_open_by_dev+0x181/0x240 block/bdev.c:1054 setup_bdev_super+0x5a/0x5b0 fs/super.c:1558 get_tree_bdev_flags+0x388/0x4f0 fs/super.c:1638 vfs_get_tree+0x92/0x2a0 fs/super.c:1700 fc_mount fs/namespace.c:1198 [inline] do_new_mount_fc fs/namespace.c:3765 [inline] do_new_mount+0x319/0xdc0 fs/namespace.c:3841 do_mount fs/namespace.c:4174 [inline] __do_sys_mount fs/namespace.c:4390 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4367 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fea8919f34a Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fea8a01fe18 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fea8a01fea0 RCX: 00007fea8919f34a RDX: 0000200000000040 RSI: 0000200000000bc0 RDI: 00007fea8a01fe60 RBP: 0000200000000040 R08: 00007fea8a01fea0 R09: 0000000002000884 R10: 0000000002000884 R11: 0000000000000246 R12: 0000200000000bc0 R13: 00007fea8a01fe60 R14: 000000000000028a R15: 0000200000001040 ---------------- Code disassembly (best guess): 0: 48 85 ff test %rdi,%rdi 3: 0f 84 b9 0d 00 00 je 0xdc2 9: 48 83 c7 70 add $0x70,%rdi d: e8 c3 25 00 00 call 0x25d5 12: 49 89 c0 mov %rax,%r8 15: 48 8b 54 24 08 mov 0x8(%rsp),%rdx 1a: 48 8d 5a 01 lea 0x1(%rdx),%rbx 1e: 48 8b 44 24 30 mov 0x30(%rsp),%rax 23: 42 0f b6 04 20 movzbl (%rax,%r12,1),%eax 28: 84 c0 test %al,%al * 2a: 4c 89 04 24 mov %r8,(%rsp) <-- trapping instruction 2e: 0f 85 26 14 00 00 jne 0x145a 34: 48 89 dd mov %rbx,%rbp 37: 48 c1 ed 03 shr $0x3,%rbp 3b: 42 rex.X 3c: 0f .byte 0xf 3d: b6 44 mov $0x44,%dh 3f: 25 .byte 0x25