rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (1 GPs behind) idle=f9e/1/0x4000000000000002 softirq=162070/162072 fqs=0 
	(t=10501 jiffies g=178393 q=56)
rcu: rcu_preempt kthread starved for 10502 jiffies! g178393 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    25920    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:2818 [inline]
 __schedule+0x658/0x9e0 kernel/sched/core.c:3445
 schedule+0x131/0x1d0 kernel/sched/core.c:3509
 schedule_timeout+0x19d/0x2b0 kernel/time/timer.c:1807
 rcu_gp_fqs_loop kernel/rcu/tree.c:1589 [inline]
 rcu_gp_kthread+0xfd8/0x1880 kernel/rcu/tree.c:1746
 kthread+0x325/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 1
CPU: 1 PID: 24425 Comm: syz-executor.1 Not tainted 5.2.0-rc5+ #4
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d8/0x2f8 lib/dump_stack.c:113
 nmi_cpu_backtrace+0x89/0x160 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x125/0x230 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x15a/0x220 kernel/rcu/tree_stall.h:254
 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:529 [inline]
 rcu_pending kernel/rcu/tree.c:2625 [inline]
 rcu_sched_clock_irq+0xc10/0x1740 kernel/rcu/tree.c:2161
 update_process_times+0x134/0x190 kernel/time/timer.c:1639
 tick_sched_handle kernel/time/tick-sched.c:167 [inline]
 tick_sched_timer+0x257/0x410 kernel/time/tick-sched.c:1298
 __run_hrtimer kernel/time/hrtimer.c:1389 [inline]
 __hrtimer_run_queues+0x471/0x8b0 kernel/time/hrtimer.c:1451
 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1509
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1041 [inline]
 smp_apic_timer_interrupt+0xee/0x260 arch/x86/kernel/apic/apic.c:1066
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:806
 </IRQ>
RIP: 0010:save_stack mm/kasan/common.c:73 [inline]
RIP: 0010:set_track mm/kasan/common.c:79 [inline]
RIP: 0010:__kasan_kmalloc+0x173/0x1b0 mm/kasan/common.c:489
Code: 48 8b 74 f4 20 48 39 d6 72 05 4c 39 c6 72 0e ff c1 48 39 fe 72 e1 4c 39 ce 73 dc ff c9 89 c8 48 8d 7c 24 20 89 c6 8b 54 24 0c <e8> b8 3a ca 01 42 89 44 33 04 65 48 8b 04 25 28 00 00 00 48 3b 84
RSP: 0018:ffff888054926de0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000017 RBX: ffff88804dd27f20 RCX: 0000000000000018
RDX: 0000000000000c40 RSI: 0000000000000017 RDI: ffff888054926e00
RBP: ffff888054927038 R08: ffffffff87a0275f R09: ffffffff87c007b0
R10: ffffed1015d66bf8 R11: 1ffff11015d66bf7 R12: ffffed1009ba4feb
R13: 0000000000000000 R14: 0000000000000038 R15: ffff88804dd27f57
 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:497
 slab_post_alloc_hook mm/slab.h:437 [inline]
 slab_alloc mm/slab.c:3326 [inline]
 kmem_cache_alloc+0x1dd/0x2b0 mm/slab.c:3488
 mb_cache_entry_create+0x168/0x860 fs/mbcache.c:88
 ext4_xattr_block_cache_insert fs/ext4/xattr.c:2985 [inline]
 ext4_xattr_block_get fs/ext4/xattr.c:537 [inline]
 ext4_xattr_get+0x334/0x840 fs/ext4/xattr.c:652
 ext4_xattr_security_get+0x32/0x40 fs/ext4/xattr_security.c:20
 __vfs_getxattr+0x3b7/0x3f0 fs/xattr.c:311
 cap_inode_need_killpriv+0x45/0x60 security/commoncap.c:300
 security_inode_need_killpriv+0x55/0xb0 security/security.c:1252
 dentry_needs_remove_privs fs/inode.c:1802 [inline]
 file_remove_privs+0x355/0x600 fs/inode.c:1842
 __generic_file_write_iter+0x167/0x520 mm/filemap.c:3281
 ext4_file_write_iter+0x902/0x12e0 fs/ext4/file.c:266
 do_iter_readv_writev+0x6f5/0x9c0 include/linux/fs.h:1866
 do_iter_write+0x180/0x590 fs/read_write.c:970
 vfs_iter_write+0x7c/0xa0 fs/read_write.c:983
 iter_file_splice_write+0x79f/0xf40 fs/splice.c:746
 do_splice_from fs/splice.c:848 [inline]
 direct_splice_actor+0xf7/0x130 fs/splice.c:1020
 splice_direct_to_actor+0x4c6/0xb40 fs/splice.c:975
 do_splice_direct+0x279/0x3d0 fs/splice.c:1063
 do_sendfile+0x8a3/0x1110 fs/read_write.c:1464
 __do_sys_sendfile64 fs/read_write.c:1525 [inline]
 __se_sys_sendfile64 fs/read_write.c:1511 [inline]
 __x64_sys_sendfile64+0x1bc/0x220 fs/read_write.c:1511
 do_syscall_64+0xfe/0x140 arch/x86/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4592c9
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f56567c6c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000004592c9
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 00008000fffffffe R11: 0000000000000246 R12: 00007f56567c76d4
R13: 00000000004c689d R14: 00000000004db828 R15: 00000000ffffffff