gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 ====================================================== WARNING: possible circular locking dependency detected 4.19.185-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/1842 is trying to acquire lock: 00000000a0f81fc6 (&mm->mmap_sem){++++}, at: __might_fault+0xef/0x1d0 mm/memory.c:4730 but task is already holding lock: 00000000916d7464 (&cpuctx_mutex){+.+.}, at: perf_event_ctx_lock_nested+0x237/0x430 kernel/events/core.c:1283 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&cpuctx_mutex){+.+.}: perf_event_init_cpu+0xc4/0x170 kernel/events/core.c:11804 perf_event_init+0x309/0x34e kernel/events/core.c:11851 start_kernel+0x5b1/0x911 init/main.c:644 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 -> #2 (pmus_lock){+.+.}: perf_event_init_cpu+0x2c/0x170 kernel/events/core.c:11798 cpuhp_invoke_callback+0x201/0x1b80 kernel/cpu.c:169 cpuhp_up_callbacks kernel/cpu.c:583 [inline] _cpu_up+0x257/0x510 kernel/cpu.c:1144 do_cpu_up+0xdd/0x1b0 kernel/cpu.c:1179 smp_init+0x1ed/0x202 kernel/smp.c:578 kernel_init_freeable+0x60c/0xa98 init/main.c:1138 kernel_init+0xd/0x1b6 init/main.c:1062 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 -> #1 (cpu_hotplug_lock.rw_sem){++++}: __static_key_slow_dec kernel/jump_label.c:222 [inline] static_key_slow_dec+0x4f/0x90 kernel/jump_label.c:237 sw_perf_event_destroy+0x8a/0x120 kernel/events/core.c:8287 _free_event+0x32c/0x1150 kernel/events/core.c:4460 put_event kernel/events/core.c:4554 [inline] perf_mmap_close+0x6f6/0xea0 kernel/events/core.c:5558 remove_vma+0xa9/0x170 mm/mmap.c:176 remove_vma_list mm/mmap.c:2550 [inline] do_munmap+0x6f9/0xde0 mm/mmap.c:2786 mmap_region+0x2a3/0x16b0 mm/mmap.c:1700 do_mmap+0x8e8/0x1080 mm/mmap.c:1530 do_mmap_pgoff include/linux/mm.h:2326 [inline] vm_mmap_pgoff+0x197/0x200 mm/util.c:357 ksys_mmap_pgoff+0x298/0x5a0 mm/mmap.c:1580 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (&mm->mmap_sem){++++}: __might_fault mm/memory.c:4731 [inline] __might_fault+0x152/0x1d0 mm/memory.c:4716 _copy_to_user+0x29/0x100 lib/usercopy.c:25 copy_to_user include/linux/uaccess.h:155 [inline] perf_read_group kernel/events/core.c:4807 [inline] __perf_read kernel/events/core.c:4874 [inline] perf_read+0x699/0x860 kernel/events/core.c:4889 do_loop_readv_writev fs/read_write.c:701 [inline] do_loop_readv_writev fs/read_write.c:688 [inline] do_iter_read+0x471/0x630 fs/read_write.c:925 vfs_readv+0xe5/0x150 fs/read_write.c:987 do_readv+0x136/0x330 fs/read_write.c:1020 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe other info that might help us debug this: Chain exists of: &mm->mmap_sem --> pmus_lock --> &cpuctx_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&cpuctx_mutex); lock(pmus_lock); lock(&cpuctx_mutex); lock(&mm->mmap_sem); *** DEADLOCK *** 1 lock held by syz-executor.0/1842: #0: 00000000916d7464 (&cpuctx_mutex){+.+.}, at: perf_event_ctx_lock_nested+0x237/0x430 kernel/events/core.c:1283 stack backtrace: CPU: 0 PID: 1842 Comm: syz-executor.0 Not tainted 4.19.185-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+0x1fc/0x2ef lib/dump_stack.c:118 print_circular_bug.constprop.0.cold+0x2d7/0x41e kernel/locking/lockdep.c:1221 check_prev_add kernel/locking/lockdep.c:1865 [inline] check_prevs_add kernel/locking/lockdep.c:1978 [inline] validate_chain kernel/locking/lockdep.c:2419 [inline] __lock_acquire+0x30c9/0x3ff0 kernel/locking/lockdep.c:3415 lock_acquire+0x170/0x3c0 kernel/locking/lockdep.c:3907 __might_fault mm/memory.c:4731 [inline] __might_fault+0x152/0x1d0 mm/memory.c:4716 _copy_to_user+0x29/0x100 lib/usercopy.c:25 copy_to_user include/linux/uaccess.h:155 [inline] perf_read_group kernel/events/core.c:4807 [inline] __perf_read kernel/events/core.c:4874 [inline] perf_read+0x699/0x860 kernel/events/core.c:4889 do_loop_readv_writev fs/read_write.c:701 [inline] do_loop_readv_writev fs/read_write.c:688 [inline] do_iter_read+0x471/0x630 fs/read_write.c:925 vfs_readv+0xe5/0x150 fs/read_write.c:987 do_readv+0x136/0x330 fs/read_write.c:1020 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x466459 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff7781a8188 EFLAGS: 00000246 ORIG_RAX: 0000000000000013 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000466459 RDX: 0000000000000001 RSI: 00000000200002c0 RDI: 0000000000000006 RBP: 00000000004bf9fb R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffe6f9c469f R14: 00007ff7781a8300 R15: 0000000000022000 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 Restarting kernel threads ... done. Restarting kernel threads ... gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" done. gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 audit: type=1804 audit(1617897966.928:78): pid=1920 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=invalid_pcr cause=open_writers comm="syz-executor.1" name="/root/syzkaller-testdir690230330/syzkaller.Mm34R6/1238/bus" dev="sda1" ino=14364 res=1 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 overlayfs: unrecognized mount option "0xffffffffffffffff" or missing value tmpfs: Bad mount option *I͇f -D3:C|uP. e{Ըfwod% @DIyzIBэ(g overlayfs: unrecognized mount option "0xffffffffffffffff" or missing value tmpfs: Bad mount option *I͇f -D3:C|uP. e{Ըfwod% @DIyzIBэ(g gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 overlayfs: unrecognized mount option "lwerdir=.:file0" or missing value overlayfs: unrecognized mount option "uppeidir=./bus" or missing value gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" overlayfs: unrecognized mount option "lwerdir=.:file0" or missing value overlayfs: unrecognized mount option "uppeidir=./bus" or missing value gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 overlayfs: unrecognized mount option "w1" or missing value gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 overlayfs: unrecognized mount option "w1" or missing value gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22 gfs2: fsid=_dev_bsg: Trying to join cluster "lock_nolock", "_dev_bsg" gfs2: fsid=_dev_bsg: Now mounting FS... gfs2: not a GFS2 filesystem gfs2: fsid=_dev_bsg: can't read superblock gfs2: fsid=_dev_bsg: can't read superblock: -22