binder: 15092:15103 BC_DEAD_BINDER_DONE 0000000000000000 not found ============================================ WARNING: possible recursive locking detected binder: 15092:15109 BC_DEAD_BINDER_DONE 0000000000000000 not found 4.15.0-rc8+ #269 Not tainted -------------------------------------------- syz-executor7/15101 is trying to acquire lock: (&vq->mutex){+.+.}, at: [<000000000d3ba34a>] vhost_dev_lock_vqs drivers/vhost/vhost.c:907 [inline] (&vq->mutex){+.+.}, at: [<000000000d3ba34a>] vhost_process_iotlb_msg drivers/vhost/vhost.c:997 [inline] (&vq->mutex){+.+.}, at: [<000000000d3ba34a>] vhost_chr_write_iter+0x278/0x1580 drivers/vhost/vhost.c:1046 but task is already holding lock: (&vq->mutex){+.+.}, at: [<000000000d3ba34a>] vhost_dev_lock_vqs drivers/vhost/vhost.c:907 [inline] (&vq->mutex){+.+.}, at: [<000000000d3ba34a>] vhost_process_iotlb_msg drivers/vhost/vhost.c:997 [inline] (&vq->mutex){+.+.}, at: [<000000000d3ba34a>] vhost_chr_write_iter+0x278/0x1580 drivers/vhost/vhost.c:1046 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&vq->mutex); lock(&vq->mutex); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by syz-executor7/15101: #0: (&vq->mutex){+.+.}, at: [<000000000d3ba34a>] vhost_dev_lock_vqs drivers/vhost/vhost.c:907 [inline] #0: (&vq->mutex){+.+.}, at: [<000000000d3ba34a>] vhost_process_iotlb_msg drivers/vhost/vhost.c:997 [inline] #0: (&vq->mutex){+.+.}, at: [<000000000d3ba34a>] vhost_chr_write_iter+0x278/0x1580 drivers/vhost/vhost.c:1046 stack backtrace: CPU: 1 PID: 15101 Comm: syz-executor7 Not tainted 4.15.0-rc8+ #269 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 print_deadlock_bug kernel/locking/lockdep.c:1756 [inline] check_deadlock kernel/locking/lockdep.c:1800 [inline] validate_chain kernel/locking/lockdep.c:2396 [inline] __lock_acquire+0xe8f/0x3e00 kernel/locking/lockdep.c:3426 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3914 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 vhost_dev_lock_vqs drivers/vhost/vhost.c:907 [inline] vhost_process_iotlb_msg drivers/vhost/vhost.c:997 [inline] vhost_chr_write_iter+0x278/0x1580 drivers/vhost/vhost.c:1046 vhost_net_chr_write_iter+0x59/0x70 drivers/vhost/net.c:1353 call_write_iter include/linux/fs.h:1772 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x684/0x970 fs/read_write.c:482 vfs_write+0x189/0x510 fs/read_write.c:544 SYSC_write fs/read_write.c:589 [inline] SyS_write+0xef/0x220 fs/read_write.c:581 entry_SYSCALL_64_fastpath+0x29/0xa0 RIP: 0033:0x452ee9 RSP: 002b:00007f958ce60c58 EFLAGS: 00000212 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452ee9 RDX: 0000000000000068 RSI: 00000000201c4000 RDI: 0000000000000014 RBP: 00000000000003d6 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 00000000006f4cb0 R13: 00000000ffffffff R14: 00007f958ce616d4 R15: 0000000000000000 binder: 15216:15217 IncRefs 0 refcount change on invalid ref 2 ret -22 audit: type=1326 audit(1516425937.287:762): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=15222 comm="syz-executor6" exe="/root/syz-executor6" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452ee9 code=0x7ffc0000 audit: type=1326 audit(1516425937.289:763): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=15222 comm="syz-executor6" exe="/root/syz-executor6" sig=0 arch=c000003e syscall=2 compat=0 ip=0x40d1e1 code=0x7ffc0000 audit: type=1326 audit(1516425937.289:764): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=15222 comm="syz-executor6" exe="/root/syz-executor6" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452ee9 code=0x7ffc0000 audit: type=1326 audit(1516425937.291:765): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=15222 comm="syz-executor6" exe="/root/syz-executor6" sig=0 arch=c000003e syscall=16 compat=0 ip=0x452ee9 code=0x7ffc0000 audit: type=1326 audit(1516425937.291:766): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=15222 comm="syz-executor6" exe="/root/syz-executor6" sig=0 arch=c000003e syscall=202 compat=0 ip=0x452ee9 code=0x7ffc0000 audit: type=1326 audit(1516425937.293:767): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 pid=15222 comm="syz-executor6" exe="/root/syz-executor6" sig=0 arch=c000003e syscall=16 compat=0 ip=0x452ee9 code=0x7ffc0000 binder_alloc: binder_alloc_mmap_handler: 15216 20000000-20002000 already mapped failed -16 binder: BINDER_SET_CONTEXT_MGR already set binder: 15216:15228 ioctl 40046207 0 returned -16 binder: 15216:15245 IncRefs 0 refcount change on invalid ref 2 ret -22 dccp_close: ABORT with 4294967275 bytes unread IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready