Re: [syzbot] INFO: rcu detected stall in gc_worker (3)

syzbot
2022-07-31T08:03:20Z

WARNING in __hrtimer_run_queues

------------[ cut here ]------------
On CPU1 hrtimer tick_sched_timer took more than 4 ticks
WARNING: CPU: 1 PID: 0 at kernel/time/hrtimer.c:1689 __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
WARNING: CPU: 1 PID: 0 at kernel/time/hrtimer.c:1689 __hrtimer_run_queues+0xe3c/0x1000 kernel/time/hrtimer.c:1754
Modules linked in:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.17.0-rc6-next-20220303-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
RIP: 0010:__run_hrtimer kernel/time/hrtimer.c:1689 [inline]
RIP: 0010:__hrtimer_run_queues+0xe3c/0x1000 kernel/time/hrtimer.c:1754
Code: fa 48 c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e b7 01 00 00 41 8b 77 40 48 c7 c7 a0 68 ce 89 48 8b 54 24 08 e8 50 82 b0 07 <0f> 0b e9 62 f4 ff ff e8 c8 42 5c 00 e9 5c f6 ff ff 48 8b 7c 24 18
RSP: 0018:ffffc900001e0e30 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000
RDX: ffff888011a21d40 RSI: ffffffff81602878 RDI: fffff5200003c1b8
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815fd23e R11: 0000000000000000 R12: ffff8880b9d2afa0
R13: 0000000000000000 R14: ffff8880b9d2a680 R15: ffff8880b9d2a600
FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fba30aa0097 CR3: 000000002354c000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1816
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
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline]
RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:130 [inline]
RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:116 [inline]
RIP: 0010:acpi_idle_do_entry+0x1c6/0x250 drivers/acpi/processor_idle.c:556
Code: 89 de e8 4d e6 18 f8 84 db 75 ac e8 64 e2 18 f8 e8 1f 2b 1f f8 eb 0c e8 58 e2 18 f8 0f 00 2d 91 ed d1 00 e8 4c e2 18 f8 fb f4 <9c> 5b 81 e3 00 02 00 00 fa 31 ff 48 89 de e8 c7 e4 18 f8 48 85 db
RSP: 0018:ffffc90000177d18 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff888011a21d40 RSI: ffffffff896045f4 RDI: 0000000000000000
RBP: ffff888016545864 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff817f7138 R11: 0000000000000000 R12: 0000000000000001
R13: ffff888016545800 R14: ffff888016545864 R15: ffff8880199b0004
acpi_idle_enter+0x361/0x500 drivers/acpi/processor_idle.c:692
cpuidle_enter_state+0x1b1/0xc80 drivers/cpuidle/cpuidle.c:237
cpuidle_enter+0x4a/0xa0 drivers/cpuidle/cpuidle.c:351
call_cpuidle kernel/sched/idle.c:158 [inline]
cpuidle_idle_call kernel/sched/idle.c:239 [inline]
do_idle+0x3e8/0x590 kernel/sched/idle.c:306
cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
start_secondary+0x265/0x340 arch/x86/kernel/smpboot.c:272
secondary_startup_64_no_verify+0xc3/0xcb
</TASK>
----------------
Code disassembly (best guess):
0: 89 de mov %ebx,%esi
2: e8 4d e6 18 f8 callq 0xf818e654
7: 84 db test %bl,%bl
9: 75 ac jne 0xffffffb7
b: e8 64 e2 18 f8 callq 0xf818e274
10: e8 1f 2b 1f f8 callq 0xf81f2b34
15: eb 0c jmp 0x23
17: e8 58 e2 18 f8 callq 0xf818e274
1c: 0f 00 2d 91 ed d1 00 verw 0xd1ed91(%rip) # 0xd1edb4
23: e8 4c e2 18 f8 callq 0xf818e274
28: fb sti
29: f4 hlt
* 2a: 9c pushfq <-- trapping instruction
2b: 5b pop %rbx
2c: 81 e3 00 02 00 00 and $0x200,%ebx
32: fa cli
33: 31 ff xor %edi,%edi
35: 48 89 de mov %rbx,%rsi
38: e8 c7 e4 18 f8 callq 0xf818e504
3d: 48 85 db test %rbx,%rbx

Tested on:

commit: 91265a6d Add linux-next specific files for 20220303
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
console output: https://syzkaller.appspot.com/x/log.txt?x=11658846080000
kernel config: https://syzkaller.appspot.com/x/.config?x=617f79440a35673a
dashboard link: https://syzkaller.appspot.com/bug?extid=eec403943a2a2455adaa
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
patch: https://syzkaller.appspot.com/x/patch.diff?x=161e281e080000