INFO: task syz-executor.5:5624 blocked for more than 140 seconds. Not tainted 4.14.198-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28912 5624 6364 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_timeout+0x80a/0xe90 kernel/time/timer.c:1731 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common+0x272/0x430 kernel/sched/completion.c:123 ucma_close+0xfc/0x340 drivers/infiniband/core/ucma.c:1749 __fput+0x25f/0x7a0 fs/file_table.c:210 task_work_run+0x11f/0x190 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:191 [inline] exit_to_usermode_loop+0x1ad/0x200 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x4177e1 RSP: 002b:00007ffd4719a500 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00000000004177e1 RDX: 0000001b31420000 RSI: 000000000000086e RDI: 0000000000000003 RBP: 0000000000000001 R08: 00000000216a486e R09: 00000000216a4872 R10: 00007ffd4719a5f0 R11: 0000000000000293 R12: 0000000001190500 R13: 000000000010cfec R14: ffffffffffffffff R15: 000000000118bf2c Showing all locks held in the system: 1 lock held by khungtaskd/1068: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1068 Comm: khungtaskd Not tainted 4.14.198-syzkaller #0 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+0x1b2/0x283 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x17f lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3649 Comm: systemd-journal Not tainted 4.14.198-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8880940be280 task.stack: ffff8880940c0000 RIP: 0010:__read_seqcount_retry include/linux/seqlock.h:205 [inline] RIP: 0010:read_seqcount_retry include/linux/seqlock.h:221 [inline] RIP: 0010:read_seqretry include/linux/seqlock.h:439 [inline] RIP: 0010:zone_span_seqretry include/linux/memory_hotplug.h:84 [inline] RIP: 0010:page_outside_zone_boundaries+0x190/0x310 mm/page_alloc.c:500 RSP: 0018:ffff8880940c7968 EFLAGS: 00000802 RAX: 0000000000000000 RBX: ffff88812fffb6c0 RCX: 00000000000ff000 RDX: 0000000000000000 RSI: 0000000000089d8e RDI: ffff88812fffb730 RBP: dffffc0000000000 R08: 0000000000001000 R09: 0000000000000002 R10: 0000000000000000 R11: ffff8880940be280 R12: 0000000000000000 R13: fffffbfff0fa2d20 R14: 1ffffffff0fa2d22 R15: ffff88812fffb750 FS: 00007f77804d48c0(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f777dcfc000 CR3: 00000000952f2000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: bad_range mm/page_alloc.c:524 [inline] __free_one_page mm/page_alloc.c:827 [inline] free_one_page+0x119/0x1210 mm/page_alloc.c:1178 __free_pages_ok+0x3f1/0xeb0 mm/page_alloc.c:1267 slab_destroy mm/slab.c:1723 [inline] slabs_destroy+0x90/0xd0 mm/slab.c:1739 cache_flusharray mm/slab.c:3483 [inline] ___cache_free+0x213/0x2c0 mm/slab.c:3525 qlink_free mm/kasan/quarantine.c:147 [inline] qlist_free_all+0x79/0x140 mm/kasan/quarantine.c:166 quarantine_reduce+0x185/0x200 mm/kasan/quarantine.c:259 kasan_kmalloc+0xa2/0x160 mm/kasan/kasan.c:536 slab_post_alloc_hook mm/slab.h:442 [inline] slab_alloc mm/slab.c:3390 [inline] kmem_cache_alloc+0x111/0x3c0 mm/slab.c:3550 prepare_creds+0x39/0x490 kernel/cred.c:255 SYSC_faccessat fs/open.c:365 [inline] SyS_faccessat+0x7b/0x680 fs/open.c:353 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f777f7909c7 RSP: 002b:00007ffe58ffc1b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 00007ffe58fff1e0 RCX: 00007f777f7909c7 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000055a9d43189a3 RBP: 00007ffe58ffc300 R08: 000055a9d430e3e5 R09: 0000000000000018 R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 000055a9d605a8c0 R15: 00007ffe58ffc7f0 Code: c1 ea 03 80 3c 2a 00 0f 85 1a 01 00 00 48 8b 34 24 48 8b 4b 70 4c 39 c6 73 45 41 bc 01 00 00 00 4c 89 fa 48 c1 ea 03 0f b6 14 2a <84> d2 74 09 80 fa 03 0f 8e 0b 01 00 00 3b 83 90 00 00 00 0f 85