syzbot


INFO: rcu detected stall in __fdget

Status: auto-obsoleted due to no activity on 2024/09/30 09:19
Reported-by: syzbot+8a7bf5b10fec81864209@syzkaller.appspotmail.com
First crash: 165d, last: 165d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in __fdget fs 1 124d 124d 0/28 auto-obsoleted due to no activity on 2024/10/31 15:19

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P13130/1:b..l P13155/1:b..l
	(detected by 1, t=10502 jiffies, g=70549, q=107 ncpus=2)
task:syz-executor.3  state:R  running task     stack:26168 pid:13155 ppid:10540  flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:lock_acquire+0x92/0x5a0 kernel/locking/lockdep.c:5630
Code: 81 4c 8d 64 24 40 49 c1 ec 03 48 b8 f1 f1 f1 f1 00 f2 f2 f2 4b 89 04 2c 43 c7 44 2c 09 f2 f2 f2 00 43 c7 44 2c 11 f3 f3 f3 f3 <66> 43 c7 44 2c 15 f3 f3 43 c6 44 2c 17 f3 0f 1f 44 00 00 65 8b 1d
RSP: 0018:ffffc90009b87ce0 EFLAGS: 00000a02
RAX: f2f2f200f1f1f1f1 RBX: 0000000000000003 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8d12acc0
RBP: ffffc90009b87e28 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92001370fa4
R13: dffffc0000000000 R14: 0000000000000000 R15: ffffffff81f926b8
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 __fget_files+0x45/0x4a0 fs/file.c:913
 __fget fs/file.c:922 [inline]
 __fget_light fs/file.c:1022 [inline]
 __fdget+0x175/0x210 fs/file.c:1030
 fdget include/linux/file.h:64 [inline]
 __do_sys_ioctl fs/ioctl.c:858 [inline]
 __se_sys_ioctl+0x1f/0x160 fs/ioctl.c:856
 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: 0033:0x7fc9c427d0a9
RSP: 002b:00007fc9c50a60c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fc9c43b4050 RCX: 00007fc9c427d0a9
RDX: 0000000020000000 RSI: 00000000402c542c RDI: 0000000000000004
RBP: 00007fc9c42ec074 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007fc9c43b4050 R15: 00007fffe776e468
 </TASK>
task:syz-executor.4  state:R  running task     stack:25464 pid:13130 ppid:7456   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0x0/0x80 kernel/kcov.c:305
Code: 39 c8 77 22 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 84 d8 77 7e 65 8b 05 85 d8 77 7e a9 00 01
RSP: 0018:ffffc900057efb18 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0000000000040000
RDX: ffffc90005542000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900057efcb0 R08: ffffffff8a817ca4 R09: ffffffff8a817bcd
R10: 0000000000000003 R11: ffff88807644d940 R12: ffffc900057efc00
R13: dffffc0000000000 R14: ffff88807dc22c0c R15: ffff888016a8bd58
 mt_locked lib/maple_tree.c:807 [inline]
 mt_slot lib/maple_tree.c:814 [inline]
 mtree_lookup_walk lib/maple_tree.c:3941 [inline]
 mtree_load+0x999/0xdf0 lib/maple_tree.c:6262
 vma_lookup include/linux/mm.h:2865 [inline]
 do_pages_stat_array mm/migrate.c:1916 [inline]
 do_pages_stat mm/migrate.c:1992 [inline]
 kernel_move_pages mm/migrate.c:2079 [inline]
 __do_sys_move_pages mm/migrate.c:2090 [inline]
 __se_sys_move_pages+0x1506/0x19d0 mm/migrate.c:2085
 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: 0033:0x7f48cba7d0a9
RSP: 002b:00007f48cc8c50c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000117
RAX: ffffffffffffffda RBX: 00007f48cbbb3f80 RCX: 00007f48cba7d0a9
RDX: 0000000020000000 RSI: 20000000000001ab RDI: 0000000000000000
RBP: 00007f48cbaec074 R08: 0000000020000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f48cbbb3f80 R15: 00007ffdaa1724f8
 </TASK>
rcu: rcu_preempt kthread starved for 10160 jiffies! g70549 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:26744 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 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:308
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.1.94-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [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:113 [inline]
RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:572
Code: 43 f5 f6 48 83 e3 08 0f 85 0b 01 00 00 4c 8d 74 24 20 e8 a4 02 fc f6 0f 1f 44 00 00 e8 fa 3f f5 f6 0f 00 2d e3 10 b2 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 ab c0 4c f7
RSP: 0018:ffffc90000177b80 EFLAGS: 000002d3
RAX: ffffffff8a955356 RBX: 0000000000000000 RCX: ffff888012739dc0
RDX: 0000000000000000 RSI: ffffffff8aec0240 RDI: ffffffff8b3d4660
RBP: ffffc90000177c10 R08: ffffffff8a955338 R09: ffffed10024e73b9
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200002ef70
R13: ffff888017ba8004 R14: ffffc90000177ba0 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d225000 CR3: 0000000054119000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:709
 cpuidle_enter_state+0x516/0xf80 drivers/cpuidle/cpuidle.c:239
 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:356
 call_cpuidle kernel/sched/idle.c:155 [inline]
 cpuidle_idle_call kernel/sched/idle.c:236 [inline]
 do_idle+0x3ce/0x680 kernel/sched/idle.c:303
 cpu_startup_entry+0x3d/0x60 kernel/sched/idle.c:401
 start_secondary+0xe4/0xf0 arch/x86/kernel/smpboot.c:281
 secondary_startup_64_no_verify+0xcf/0xdb
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/22 09:18 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in __fdget
* Struck through repros no longer work on HEAD.