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INFO: rcu detected stall in msr_read

Status: auto-obsoleted due to no activity on 2024/11/19 16:03
Reported-by: syzbot+bf78a46506069496f4f1@syzkaller.appspotmail.com
First crash: 162d, last: 103d
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: rcu detected stall in msr_read 1 93d 93d 0/3 upstream: reported on 2024/08/21 20:07
upstream INFO: rcu detected stall in msr_read kernel 8 106d 167d 0/28 auto-obsoleted due to no activity on 2024/11/07 00:24

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10499 ticks this GP) idle=8ff4/1/0x4000000000000000 softirq=18064/18064 fqs=0
	(t=10500 jiffies g=20909 q=7 ncpus=2)
rcu: rcu_preempt kthread timer wakeup didn't happen for 10499 jiffies! g20909 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=11268
rcu: rcu_preempt kthread starved for 10500 jiffies! g20909 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:25528 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5499 Comm: syz.1.495 Not tainted 6.1.104-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:235 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x4/0x80 kernel/kcov.c:290
Code: 49 ff c2 4c 89 12 48 c7 44 11 08 06 00 00 00 48 89 7c 11 10 48 89 74 11 18 4c 89 44 11 20 c3 0f 1f 80 00 00 00 00 4c 8b 04 24 <65> 48 8b 15 d4 cc 77 7e 65 8b 05 d5 cc 77 7e a9 00 01 ff 00 74 10
RSP: 0000:ffffc900001e0d58 EFLAGS: 00000047
RAX: 0000000000000001 RBX: 0000000000000001 RCX: ffffffff8179ceb9
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffffc900001e0eb0 R08: ffffffff8179ced6 R09: fffffbfff1d338d6
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880b992a4c0
R13: 0000000000000001 R14: ffff8880b992a4c0 R15: 0000000000000001
FS:  00007f1f7d36d6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007feebfdee000 CR3: 0000000061a44000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 variable_test_bit arch/x86/include/asm/bitops.h:228 [inline]
 arch_test_bit arch/x86/include/asm/bitops.h:240 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
 cpumask_test_cpu include/linux/cpumask.h:444 [inline]
 cpu_online include/linux/cpumask.h:1030 [inline]
 trace_hrtimer_expire_exit include/trace/events/timer.h:286 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1689 [inline]
 __hrtimer_run_queues+0x686/0xe50 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:finish_task_switch+0x1d3/0x810 kernel/sched/core.c:5120
Code: 31 0b 00 48 83 c4 08 4c 89 f7 e8 68 31 00 00 0f 1f 44 00 00 4c 89 f7 e8 eb 4b 50 09 e8 d6 22 32 00 fb 49 8d bc 24 f8 15 00 00 <48> 89 f8 48 c1 e8 03 49 bd 00 00 00 00 00 fc ff df 42 0f b6 04 28
RSP: 0000:ffffc90003cff5e8 EFLAGS: 00000282
RAX: bf1d0dfca249d700 RBX: ffff888029361df4 RCX: ffffffff91f32103
RDX: dffffc0000000000 RSI: ffffffff8b0c0260 RDI: ffff888022c7b3b8
RBP: ffffc90003cff630 R08: dffffc0000000000 R09: ffffed1017327539
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888022c79dc0
R13: 1ffff110173276e3 R14: ffff8880b993a9c0 R15: ffff8880b993b718
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x1447/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0xac/0x300 kernel/time/timer.c:1941
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x350/0x610 kernel/sched/completion.c:138
 rdmsr_safe_on_cpu+0x168/0x310 arch/x86/lib/msr-smp.c:183
 msr_read+0x168/0x1f0 arch/x86/kernel/msr.c:67
 vfs_read+0x2ed/0xbf0 fs/read_write.c:468
 ksys_read+0x19c/0x2c0 fs/read_write.c:613
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1f7c5779f9
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1f7d36d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f1f7c705f80 RCX: 00007f1f7c5779f9
RDX: 0000000000018ff8 RSI: 0000000020019680 RDI: 0000000000000004
RBP: 00007f1f7c5e58ee R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f1f7c705f80 R15: 00007ffdbd95fac8
 </TASK>
CPU: 0 PID: 5501 Comm: syz.1.495 Not tainted 6.1.104-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:csd_lock_wait kernel/smp.c:424 [inline]
RIP: 0010:smp_call_function_many_cond+0x1fb0/0x3460 kernel/smp.c:998
Code: 2f 44 89 ee 83 e6 01 31 ff e8 4c 40 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 0a e8 d7 3c 0b 00 e9 1b ff ff ff f3 90 <42> 0f b6 04 2b 84 c0 75 14 41 f7 07 01 00 00 00 0f 84 fe fe ff ff
RSP: 0018:ffffc9000389eba0 EFLAGS: 00000246
RAX: ffffffff817f634b RBX: 1ffff110173281b1 RCX: 0000000000040000
RDX: ffffc90003aa1000 RSI: 000000000003ffff RDI: 0000000000040000
RBP: ffffc9000389ef80 R08: ffffffff817f6314 R09: fffffbfff20e7445
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000800000000
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880b9940d88
FS:  00007f1f7d34c6c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200012c0 CR3: 0000000061a44000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1166
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1334 [inline]
 text_poke_bp_batch+0x2bb/0x940 arch/x86/kernel/alternative.c:1534
 text_poke_flush arch/x86/kernel/alternative.c:1725 [inline]
 text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1732
 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146
 static_key_slow_inc_cpuslocked+0xaf/0x140 kernel/jump_label.c:165
 static_key_slow_inc+0x16/0x30 kernel/jump_label.c:186
 clsact_init+0x90/0x2a0 net/sched/sch_ingress.c:231
 qdisc_create+0x8a1/0x1220 net/sched/sch_api.c:1314
 tc_modify_qdisc+0xb5f/0x1d70 net/sched/sch_api.c:1734
 rtnetlink_rcv_msg+0x818/0xff0 net/core/rtnetlink.c:6121
 netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2508
 netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline]
 netlink_unicast+0x7d8/0x970 net/netlink/af_netlink.c:1352
 netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1874
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x5a5/0x8f0 net/socket.c:2514
 ___sys_sendmsg net/socket.c:2568 [inline]
 __sys_sendmsg+0x2a9/0x390 net/socket.c:2597
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1f7c5779f9
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1f7d34c038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f1f7c706058 RCX: 00007f1f7c5779f9
RDX: 0000000000000000 RSI: 00000000200012c0 RDI: 0000000000000007
RBP: 00007f1f7c5e58ee R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f1f7c706058 R15: 00007ffdbd95fac8
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 5499 Comm: syz.1.495 Not tainted 6.1.104-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:235 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x4/0x80 kernel/kcov.c:304
Code: 89 f8 89 f6 49 ff c2 4c 89 11 48 c7 44 0a 08 03 00 00 00 48 89 44 0a 10 48 89 74 0a 18 4c 89 44 0a 20 c3 0f 1f 00 4c 8b 04 24 <65> 48 8b 15 d4 cb 77 7e 65 8b 05 d5 cb 77 7e a9 00 01 ff 00 74 10
RSP: 0000:ffffc900001e0cb8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffffffff88cea3d0 RCX: ffff888022c79dc0
RDX: 0000000080010001 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffffffff88cea482 R09: ffffed102966542c
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88814b32a000
R13: ffff88814b32a360 R14: dffffc0000000000 R15: 17f2dbc138000000
FS:  00007f1f7d36d6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007feebfdee000 CR3: 0000000061a44000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 rcu_read_unlock include/linux/rcupdate.h:820 [inline]
 advance_sched+0x782/0x970 net/sched/sch_taprio.c:755
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x5e5/0xe50 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline]
 __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:finish_task_switch+0x1d3/0x810 kernel/sched/core.c:5120
Code: 31 0b 00 48 83 c4 08 4c 89 f7 e8 68 31 00 00 0f 1f 44 00 00 4c 89 f7 e8 eb 4b 50 09 e8 d6 22 32 00 fb 49 8d bc 24 f8 15 00 00 <48> 89 f8 48 c1 e8 03 49 bd 00 00 00 00 00 fc ff df 42 0f b6 04 28
RSP: 0000:ffffc90003cff5e8 EFLAGS: 00000282
RAX: bf1d0dfca249d700 RBX: ffff888029361df4 RCX: ffffffff91f32103
RDX: dffffc0000000000 RSI: ffffffff8b0c0260 RDI: ffff888022c7b3b8
RBP: ffffc90003cff630 R08: dffffc0000000000 R09: ffffed1017327539
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888022c79dc0
R13: 1ffff110173276e3 R14: ffff8880b993a9c0 R15: ffff8880b993b718
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x1447/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_timeout+0xac/0x300 kernel/time/timer.c:1941
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x350/0x610 kernel/sched/completion.c:138
 rdmsr_safe_on_cpu+0x168/0x310 arch/x86/lib/msr-smp.c:183
 msr_read+0x168/0x1f0 arch/x86/kernel/msr.c:67
 vfs_read+0x2ed/0xbf0 fs/read_write.c:468
 ksys_read+0x19c/0x2c0 fs/read_write.c:613
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f1f7c5779f9
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1f7d36d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f1f7c705f80 RCX: 00007f1f7c5779f9
RDX: 0000000000018ff8 RSI: 0000000020019680 RDI: 0000000000000004
RBP: 00007f1f7c5e58ee R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f1f7c705f80 R15: 00007ffdbd95fac8
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/11 16:03 linux-6.1.y 36790ef5e00b 6f4edef4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in msr_read
2024/06/13 11:28 linux-6.1.y ae9f2a70d69e 2aa5052f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in msr_read
* Struck through repros no longer work on HEAD.