====================================================== WARNING: possible circular locking dependency detected 5.8.0-rc4-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.1/4807 is trying to acquire lock: ffffffff89c3a988 (delayed_uprobe_lock){+.+.}-{3:3}, at: uprobe_clear_state+0x47/0x3b0 kernel/events/uprobes.c:1550 but task is already holding lock: ffffffff89c6c360 (fs_reclaim){+.+.}-{0:0}, at: fs_reclaim_release mm/page_alloc.c:4202 [inline] ffffffff89c6c360 (fs_reclaim){+.+.}-{0:0}, at: fs_reclaim_release mm/page_alloc.c:4198 [inline] ffffffff89c6c360 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4227 [inline] ffffffff89c6c360 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4244 [inline] ffffffff89c6c360 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath.constprop.0+0x1554/0x2780 mm/page_alloc.c:4650 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (fs_reclaim){+.+.}-{0:0}: __fs_reclaim_acquire mm/page_alloc.c:4183 [inline] fs_reclaim_acquire+0x2f/0x40 mm/page_alloc.c:4194 slab_pre_alloc_hook mm/slab.h:564 [inline] slab_alloc mm/slab.c:3306 [inline] kmem_cache_alloc_trace+0x29/0x2d0 mm/slab.c:3549 kmalloc include/linux/slab.h:555 [inline] kzalloc include/linux/slab.h:669 [inline] delayed_uprobe_add kernel/events/uprobes.c:304 [inline] update_ref_ctr+0x4b6/0x700 kernel/events/uprobes.c:438 uprobe_write_opcode+0xe07/0x1650 kernel/events/uprobes.c:497 install_breakpoint kernel/events/uprobes.c:915 [inline] install_breakpoint.isra.0+0x5a5/0x7c0 kernel/events/uprobes.c:897 uprobe_mmap+0x5d7/0x1050 kernel/events/uprobes.c:1394 mmap_region+0x5cf/0x1590 mm/mmap.c:1818 do_mmap+0xca8/0x1170 mm/mmap.c:1545 do_mmap_pgoff include/linux/mm.h:2596 [inline] vm_mmap_pgoff+0x197/0x200 mm/util.c:506 ksys_mmap_pgoff+0x455/0x5a0 mm/mmap.c:1595 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #0 (delayed_uprobe_lock){+.+.}-{3:3}: check_prev_add kernel/locking/lockdep.c:2496 [inline] check_prevs_add kernel/locking/lockdep.c:2601 [inline] validate_chain kernel/locking/lockdep.c:3218 [inline] __lock_acquire+0x2acb/0x56e0 kernel/locking/lockdep.c:4380 lock_acquire+0x1f1/0xad0 kernel/locking/lockdep.c:4959 __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x134/0x10d0 kernel/locking/mutex.c:1103 uprobe_clear_state+0x47/0x3b0 kernel/events/uprobes.c:1550 __mmput+0x73/0x470 kernel/fork.c:1089 mmput+0x53/0x60 kernel/fork.c:1114 binder_alloc_free_page+0x441/0xf90 drivers/android/binder_alloc.c:950 __list_lru_walk_one+0x178/0x5c0 mm/list_lru.c:222 list_lru_walk_one mm/list_lru.c:266 [inline] list_lru_walk_node+0x67/0x2a0 mm/list_lru.c:295 list_lru_walk include/linux/list_lru.h:215 [inline] binder_shrink_scan+0x123/0x190 drivers/android/binder_alloc.c:984 do_shrink_slab+0x3c6/0xab0 mm/vmscan.c:518 shrink_slab+0x16f/0x5c0 mm/vmscan.c:679 shrink_node_memcgs mm/vmscan.c:2658 [inline] shrink_node+0x519/0x1b60 mm/vmscan.c:2770 shrink_zones mm/vmscan.c:2973 [inline] do_try_to_free_pages+0x38b/0x1340 mm/vmscan.c:3026 try_to_free_pages+0x29a/0x8b0 mm/vmscan.c:3265 __perform_reclaim mm/page_alloc.c:4223 [inline] __alloc_pages_direct_reclaim mm/page_alloc.c:4244 [inline] __alloc_pages_slowpath.constprop.0+0x949/0x2780 mm/page_alloc.c:4650 __alloc_pages_nodemask+0x68f/0x930 mm/page_alloc.c:4863 alloc_pages_current+0x187/0x280 mm/mempolicy.c:2292 alloc_pages include/linux/gfp.h:545 [inline] alloc_mmu_pages+0x7f/0x170 arch/x86/kvm/mmu/mmu.c:5671 kvm_mmu_create+0x3cb/0x560 arch/x86/kvm/mmu/mmu.c:5704 kvm_arch_vcpu_create+0x16d/0xb70 arch/x86/kvm/x86.c:9433 kvm_vm_ioctl_create_vcpu arch/x86/kvm/../../../virt/kvm/kvm_main.c:3060 [inline] kvm_vm_ioctl+0x1547/0x23c0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3621 vfs_ioctl fs/ioctl.c:48 [inline] ksys_ioctl+0x11a/0x180 fs/ioctl.c:753 __do_sys_ioctl fs/ioctl.c:762 [inline] __se_sys_ioctl fs/ioctl.c:760 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:760 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(delayed_uprobe_lock); lock(fs_reclaim); lock(delayed_uprobe_lock); *** DEADLOCK *** 3 locks held by syz-executor.1/4807: #0: ffffffff89c6c360 (fs_reclaim){+.+.}-{0:0}, at: fs_reclaim_release mm/page_alloc.c:4202 [inline] #0: ffffffff89c6c360 (fs_reclaim){+.+.}-{0:0}, at: fs_reclaim_release mm/page_alloc.c:4198 [inline] #0: ffffffff89c6c360 (fs_reclaim){+.+.}-{0:0}, at: __perform_reclaim mm/page_alloc.c:4227 [inline] #0: ffffffff89c6c360 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_direct_reclaim mm/page_alloc.c:4244 [inline] #0: ffffffff89c6c360 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath.constprop.0+0x1554/0x2780 mm/page_alloc.c:4650 #1: ffffffff89c46b90 (shrinker_rwsem){++++}-{3:3}, at: shrink_slab+0xc7/0x5c0 mm/vmscan.c:669 #2: ffff88808ea481e0 (&alloc->mutex){+.+.}-{3:3}, at: binder_alloc_free_page+0x4f/0xf90 drivers/android/binder_alloc.c:923 stack backtrace: CPU: 0 PID: 4807 Comm: syz-executor.1 Not tainted 5.8.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 check_noncircular+0x324/0x3e0 kernel/locking/lockdep.c:1827 check_prev_add kernel/locking/lockdep.c:2496 [inline] check_prevs_add kernel/locking/lockdep.c:2601 [inline] validate_chain kernel/locking/lockdep.c:3218 [inline] __lock_acquire+0x2acb/0x56e0 kernel/locking/lockdep.c:4380 lock_acquire+0x1f1/0xad0 kernel/locking/lockdep.c:4959 __mutex_lock_common kernel/locking/mutex.c:956 [inline] __mutex_lock+0x134/0x10d0 kernel/locking/mutex.c:1103 uprobe_clear_state+0x47/0x3b0 kernel/events/uprobes.c:1550 __mmput+0x73/0x470 kernel/fork.c:1089 mmput+0x53/0x60 kernel/fork.c:1114 binder_alloc_free_page+0x441/0xf90 drivers/android/binder_alloc.c:950 __list_lru_walk_one+0x178/0x5c0 mm/list_lru.c:222 list_lru_walk_one mm/list_lru.c:266 [inline] list_lru_walk_node+0x67/0x2a0 mm/list_lru.c:295 list_lru_walk include/linux/list_lru.h:215 [inline] binder_shrink_scan+0x123/0x190 drivers/android/binder_alloc.c:984 do_shrink_slab+0x3c6/0xab0 mm/vmscan.c:518 shrink_slab+0x16f/0x5c0 mm/vmscan.c:679 shrink_node_memcgs mm/vmscan.c:2658 [inline] shrink_node+0x519/0x1b60 mm/vmscan.c:2770 shrink_zones mm/vmscan.c:2973 [inline] do_try_to_free_pages+0x38b/0x1340 mm/vmscan.c:3026 try_to_free_pages+0x29a/0x8b0 mm/vmscan.c:3265 __perform_reclaim mm/page_alloc.c:4223 [inline] __alloc_pages_direct_reclaim mm/page_alloc.c:4244 [inline] __alloc_pages_slowpath.constprop.0+0x949/0x2780 mm/page_alloc.c:4650 __alloc_pages_nodemask+0x68f/0x930 mm/page_alloc.c:4863 alloc_pages_current+0x187/0x280 mm/mempolicy.c:2292 alloc_pages include/linux/gfp.h:545 [inline] alloc_mmu_pages+0x7f/0x170 arch/x86/kvm/mmu/mmu.c:5671 kvm_mmu_create+0x3cb/0x560 arch/x86/kvm/mmu/mmu.c:5704 kvm_arch_vcpu_create+0x16d/0xb70 arch/x86/kvm/x86.c:9433 kvm_vm_ioctl_create_vcpu arch/x86/kvm/../../../virt/kvm/kvm_main.c:3060 [inline] kvm_vm_ioctl+0x1547/0x23c0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3621 vfs_ioctl fs/ioctl.c:48 [inline] ksys_ioctl+0x11a/0x180 fs/ioctl.c:753 __do_sys_ioctl fs/ioctl.c:762 [inline] __se_sys_ioctl fs/ioctl.c:760 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:760 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cba9 Code: Bad RIP value. RSP: 002b:00007f45444f8c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004e85c0 RCX: 000000000045cba9 RDX: 0000000000000000 RSI: 000000000000ae41 RDI: 0000000000000004 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000003a3 R14: 00000000004c652f R15: 00007f45444f96d4