====================================================== WARNING: possible circular locking dependency detected 4.14.141+ #0 Not tainted ------------------------------------------------------ syz-executor.5/510 is trying to acquire lock: (pmus_lock){+.+.}, at: [<00000000e3d868c5>] swevent_hlist_get kernel/events/core.c:7896 [inline] (pmus_lock){+.+.}, at: [<00000000e3d868c5>] perf_swevent_init+0x123/0x4f0 kernel/events/core.c:7956 but task is already holding lock: (&cpuctx_mutex/1){+.+.}, at: [<00000000574a9ebd>] perf_event_ctx_lock_nested+0x15a/0x2d0 kernel/events/core.c:1240 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&cpuctx_mutex/1){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xf7/0x13e0 kernel/locking/mutex.c:893 mutex_lock_double kernel/events/core.c:9909 [inline] __perf_event_ctx_lock_double kernel/events/core.c:9968 [inline] SYSC_perf_event_open kernel/events/core.c:10233 [inline] SyS_perf_event_open+0x12cf/0x2560 kernel/events/core.c:9988 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 -> #1 (&cpuctx_mutex){+.+.}: __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xf7/0x13e0 kernel/locking/mutex.c:893 perf_event_init_cpu+0xa8/0x150 kernel/events/core.c:11231 perf_event_init+0x289/0x2c5 kernel/events/core.c:11278 start_kernel+0x583/0x890 init/main.c:645 secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:240 -> #0 (pmus_lock){+.+.}: lock_acquire+0x12b/0x360 kernel/locking/lockdep.c:3991 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xf7/0x13e0 kernel/locking/mutex.c:893 swevent_hlist_get kernel/events/core.c:7896 [inline] perf_swevent_init+0x123/0x4f0 kernel/events/core.c:7956 perf_try_init_event+0xe5/0x200 kernel/events/core.c:9347 perf_init_event kernel/events/core.c:9385 [inline] perf_event_alloc.part.0+0xd13/0x1ff0 kernel/events/core.c:9645 perf_event_alloc kernel/events/core.c:9998 [inline] SYSC_perf_event_open kernel/events/core.c:10105 [inline] SyS_perf_event_open+0x6eb/0x2560 kernel/events/core.c:9988 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 other info that might help us debug this: Chain exists of: pmus_lock --> &cpuctx_mutex --> &cpuctx_mutex/1 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&cpuctx_mutex/1); lock(&cpuctx_mutex); lock(&cpuctx_mutex/1); lock(pmus_lock); *** DEADLOCK *** 3 locks held by syz-executor.5/510: #0: (&sig->cred_guard_mutex){+.+.}, at: [<000000002210ad94>] SYSC_perf_event_open kernel/events/core.c:10085 [inline] #0: (&sig->cred_guard_mutex){+.+.}, at: [<000000002210ad94>] SyS_perf_event_open+0x1359/0x2560 kernel/events/core.c:9988 #1: (&pmus_srcu){....}, at: [<00000000daab0c08>] perf_event_alloc.part.0+0xb2b/0x1ff0 kernel/events/core.c:9639 #2: (&cpuctx_mutex/1){+.+.}, at: [<00000000574a9ebd>] perf_event_ctx_lock_nested+0x15a/0x2d0 kernel/events/core.c:1240 stack backtrace: CPU: 0 PID: 510 Comm: syz-executor.5 Not tainted 4.14.141+ #0 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xca/0x134 lib/dump_stack.c:53 print_circular_bug.isra.0.cold+0x2dc/0x425 kernel/locking/lockdep.c:1258 check_prev_add kernel/locking/lockdep.c:1901 [inline] check_prevs_add kernel/locking/lockdep.c:2018 [inline] validate_chain kernel/locking/lockdep.c:2460 [inline] __lock_acquire+0x2f5f/0x4320 kernel/locking/lockdep.c:3487 lock_acquire+0x12b/0x360 kernel/locking/lockdep.c:3991 __mutex_lock_common kernel/locking/mutex.c:756 [inline] __mutex_lock+0xf7/0x13e0 kernel/locking/mutex.c:893 swevent_hlist_get kernel/events/core.c:7896 [inline] perf_swevent_init+0x123/0x4f0 kernel/events/core.c:7956 perf_try_init_event+0xe5/0x200 kernel/events/core.c:9347 perf_init_event kernel/events/core.c:9385 [inline] perf_event_alloc.part.0+0xd13/0x1ff0 kernel/events/core.c:9645 perf_event_alloc kernel/events/core.c:9998 [inline] SYSC_perf_event_open kernel/events/core.c:10105 [inline] SyS_perf_event_open+0x6eb/0x2560 kernel/events/core.c:9988 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x459879 RSP: 002b:00007f86fa2a3c78 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000000459879 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000000020000240 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 00007f86fa2a46d4 R13: 00000000004c66e4 R14: 00000000004db758 R15: 00000000ffffffff SELinux: unrecognized netlink message: protocol=0 nlmsg_type=542 sclass=netlink_route_socket pig=539 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=542 sclass=netlink_route_socket pig=551 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=59758 sclass=netlink_route_socket pig=568 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=56920 sclass=netlink_route_socket pig=568 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=59758 sclass=netlink_route_socket pig=562 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=45140 sclass=netlink_route_socket pig=562 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=53041 sclass=netlink_route_socket pig=562 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=59758 sclass=netlink_route_socket pig=562 comm=syz-executor.0 ip6_tunnel:  xmit: Local address not yet configured! ip6_tunnel: ~ xmit: Local address not yet configured! F2FS-fs (loop4): Magic Mismatch, valid(0xf2f52010) - read(0x942b9c00) F2FS-fs (loop4): Can't find valid F2FS filesystem in 1th superblock F2FS-fs (loop4): Magic Mismatch, valid(0xf2f52010) - read(0x0) F2FS-fs (loop4): Can't find valid F2FS filesystem in 2th superblock selinux_nlmsg_perm: 16 callbacks suppressed SELinux: unrecognized netlink message: protocol=0 nlmsg_type=17463 sclass=netlink_route_socket pig=844 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=17463 sclass=netlink_route_socket pig=844 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=56920 sclass=netlink_route_socket pig=962 comm=syz-executor.5 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=59758 sclass=netlink_route_socket pig=953 comm=syz-executor.5 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=59758 sclass=netlink_route_socket pig=962 comm=syz-executor.5 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=45140 sclass=netlink_route_socket pig=962 comm=syz-executor.5 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=53041 sclass=netlink_route_socket pig=962 comm=syz-executor.5 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=59758 sclass=netlink_route_socket pig=962 comm=syz-executor.5 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=45140 sclass=netlink_route_socket pig=962 comm=syz-executor.5 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=53041 sclass=netlink_route_socket pig=962 comm=syz-executor.5 ip6_tunnel: ð xmit: Local address not yet configured! netlink: 4 bytes leftover after parsing attributes in process `syz-executor.0'. netlink: 4 bytes leftover after parsing attributes in process `syz-executor.0'. selinux_nlmsg_perm: 13 callbacks suppressed SELinux: unrecognized netlink message: protocol=0 nlmsg_type=10853 sclass=netlink_route_socket pig=1352 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=10853 sclass=netlink_route_socket pig=1360 comm=syz-executor.0 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=1425 comm=syz-executor.5 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=1425 comm=syz-executor.5