rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (10500 ticks this GP) idle=957/1/0x4000000000000000 softirq=57418/57418 fqs=4956 (t=10502 jiffies g=88005 q=3457) NMI backtrace for cpu 0 CPU: 0 PID: 30259 Comm: syz-executor.2 Not tainted 5.15.0-next-20211106-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:343 print_cpu_stall kernel/rcu/tree_stall.h:627 [inline] check_cpu_stall kernel/rcu/tree_stall.h:711 [inline] rcu_pending kernel/rcu/tree.c:3878 [inline] rcu_sched_clock_irq.cold+0x9d/0x746 kernel/rcu/tree.c:2597 update_process_times+0x16d/0x200 kernel/time/timer.c:1785 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1421 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:memset_erms+0xb/0x10 arch/x86/lib/memset_64.S:65 Code: 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3 aa <4c> 89 c8 c3 90 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 01 01 RSP: 0018:ffffc9000b33f9a8 EFLAGS: 00000246 RAX: dffffc00000000fc RBX: ffff88808e427980 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 00000000000000fc RDI: ffffed1011c84f34 RBP: 0000000000400cc0 R08: 0000000000400cc0 R09: ffffed1011c84f34 R10: 0000000000000001 R11: 0000000000000000 R12: ffff888010c42640 R13: 0000000000000020 R14: 0000000000003e0e R15: ffff88808e427940 ____kasan_kmalloc mm/kasan/common.c:505 [inline] ____kasan_kmalloc mm/kasan/common.c:472 [inline] __kasan_kmalloc+0x76/0xd0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:590 [inline] io_add_buffers fs/io_uring.c:4405 [inline] io_provide_buffers fs/io_uring.c:4439 [inline] io_issue_sqe+0x2887/0x7010 fs/io_uring.c:6705 __io_queue_sqe fs/io_uring.c:6978 [inline] io_queue_sqe fs/io_uring.c:7020 [inline] io_submit_sqe fs/io_uring.c:7223 [inline] io_submit_sqes+0x1bca/0x8a20 fs/io_uring.c:7329 __do_sys_io_uring_enter+0xf6e/0x1f50 fs/io_uring.c:10043 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7efd647baae9 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:00007efd61d30188 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00007efd648cdf60 RCX: 00007efd647baae9 RDX: 0000000020000000 RSI: 00000000000002ff RDI: 0000000000000003 RBP: 00007efd64814f25 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffefdaca8f R14: 00007efd61d30300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: 03 40 0f add 0xf(%rax),%eax 3: b6 f6 mov $0xf6,%dh 5: 48 b8 01 01 01 01 01 movabs $0x101010101010101,%rax c: 01 01 01 f: 48 0f af c6 imul %rsi,%rax 13: f3 48 ab rep stos %rax,%es:(%rdi) 16: 89 d1 mov %edx,%ecx 18: f3 aa rep stos %al,%es:(%rdi) 1a: 4c 89 c8 mov %r9,%rax 1d: c3 retq 1e: 90 nop 1f: 49 89 f9 mov %rdi,%r9 22: 40 88 f0 mov %sil,%al 25: 48 89 d1 mov %rdx,%rcx 28: f3 aa rep stos %al,%es:(%rdi) * 2a: 4c 89 c8 mov %r9,%rax <-- trapping instruction 2d: c3 retq 2e: 90 nop 2f: 49 89 fa mov %rdi,%r10 32: 40 0f b6 ce movzbl %sil,%ecx 36: 48 b8 01 01 01 01 01 movabs $0x101010101010101,%rax 3d: 01 01 01