====================================================== WARNING: possible circular locking dependency detected 4.14.103+ #18 Not tainted ------------------------------------------------------ syz-executor.1/22766 is trying to acquire lock: (&cpuctx_mutex/1){+.+.}, at: [] mutex_lock_double kernel/events/core.c:9907 [inline] (&cpuctx_mutex/1){+.+.}, at: [] __perf_event_ctx_lock_double kernel/events/core.c:9966 [inline] (&cpuctx_mutex/1){+.+.}, at: [] SYSC_perf_event_open kernel/events/core.c:10231 [inline] (&cpuctx_mutex/1){+.+.}, at: [] SyS_perf_event_open+0x11f1/0x2520 kernel/events/core.c:9986 but task is already holding lock: (&cpuctx_mutex){+.+.}, at: [] mutex_lock_double kernel/events/core.c:9906 [inline] (&cpuctx_mutex){+.+.}, at: [] __perf_event_ctx_lock_double kernel/events/core.c:9966 [inline] (&cpuctx_mutex){+.+.}, at: [] SYSC_perf_event_open kernel/events/core.c:10231 [inline] (&cpuctx_mutex){+.+.}, at: [] SyS_perf_event_open+0x11e4/0x2520 kernel/events/core.c:9986 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&cpuctx_mutex){+.+.}: -> #1 (pmus_lock){+.+.}: -> #0 (&cpuctx_mutex/1){+.+.}: other info that might help us debug this: Chain exists of: &cpuctx_mutex/1 --> pmus_lock --> &cpuctx_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&cpuctx_mutex); lock(pmus_lock); lock(&cpuctx_mutex); lock(&cpuctx_mutex/1); *** DEADLOCK *** 1 lock held by syz-executor.1/22766: #0: (&cpuctx_mutex){+.+.}, at: [] mutex_lock_double kernel/events/core.c:9906 [inline] #0: (&cpuctx_mutex){+.+.}, at: [] __perf_event_ctx_lock_double kernel/events/core.c:9966 [inline] #0: (&cpuctx_mutex){+.+.}, at: [] SYSC_perf_event_open kernel/events/core.c:10231 [inline] #0: (&cpuctx_mutex){+.+.}, at: [] SyS_perf_event_open+0x11e4/0x2520 kernel/events/core.c:9986 stack backtrace: CPU: 0 PID: 22766 Comm: syz-executor.1 Not tainted 4.14.103+ #18 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xb9/0x10e lib/dump_stack.c:53 print_circular_bug.isra.0.cold+0x2dc/0x425 kernel/locking/lockdep.c:1258 FAT-fs (loop5): Unrecognized mount option "Rl÷ôÚc©~zL" or missing value kauditd_printk_skb: 409 callbacks suppressed audit: type=1400 audit(2000000001.740:10302): avc: denied { map } for pid=22972 comm="modprobe" path="/etc/ld.so.cache" dev="sda1" ino=2503 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(2000000001.790:10303): avc: denied { map } for pid=22972 comm="modprobe" path="/lib/x86_64-linux-gnu/libkmod.so.2.1.3" dev="sda1" ino=2811 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(2000000001.790:10304): avc: denied { map } for pid=22972 comm="modprobe" path="/lib/x86_64-linux-gnu/libkmod.so.2.1.3" dev="sda1" ino=2811 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(2000000001.790:10305): avc: denied { map } for pid=22972 comm="modprobe" path="/lib/x86_64-linux-gnu/libc-2.13.so" dev="sda1" ino=2784 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(2000000001.800:10306): avc: denied { map } for pid=22972 comm="modprobe" path="/lib/x86_64-linux-gnu/libc-2.13.so" dev="sda1" ino=2784 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(2000000001.820:10307): avc: denied { map } for pid=22975 comm="blkid" path="/sbin/blkid" dev="sda1" ino=16128 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(2000000001.820:10308): avc: denied { map } for pid=22975 comm="blkid" path="/sbin/blkid" dev="sda1" ino=16128 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(2000000001.830:10309): avc: denied { map } for pid=22975 comm="blkid" path="/lib/x86_64-linux-gnu/ld-2.13.so" dev="sda1" ino=2668 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(2000000001.830:10310): avc: denied { map } for pid=22975 comm="blkid" path="/lib/x86_64-linux-gnu/ld-2.13.so" dev="sda1" ino=2668 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 audit: type=1400 audit(2000000001.830:10311): avc: denied { map } for pid=22975 comm="blkid" path="/etc/ld.so.cache" dev="sda1" ino=2503 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=23018 comm=syz-executor.1 SELinux: unrecognized netlink message: protocol=0 nlmsg_type=0 sclass=netlink_route_socket pig=23020 comm=syz-executor.1 mip6: mip6_destopt_init_state: state's mode is not 2: 0 mip6: mip6_destopt_init_state: state's mode is not 2: 0