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INFO: rcu detected stall in vfs_fallocate (4)

Status: auto-obsoleted due to no activity on 2024/09/20 02:24
Subsystems: ext4
[Documentation on labels]
First crash: 122d, last: 122d
▶ ▼ Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in vfs_fallocate ext4 6 1146d 1174d 0/28 auto-closed as invalid on 2021/12/01 16:15
linux-4.19 INFO: rcu detected stall in vfs_fallocate 1 823d 823d 0/1 auto-obsoleted due to no activity on 2022/11/19 13:27
upstream INFO: rcu detected stall in vfs_fallocate (3) ext4 1 338d 338d 0/28 auto-obsoleted due to no activity on 2024/02/16 23:28
upstream INFO: rcu detected stall in vfs_fallocate (2) ext4 1 1016d 1016d 0/28 closed as invalid on 2022/02/08 10:00
linux-5.15 INFO: rcu detected stall in vfs_fallocate 1 21d 21d 0/3 upstream: reported on 2024/10/01 21:31
linux-4.19 BUG: soft lockup in vfs_fallocate 1 1255d 1255d 0/1 auto-closed as invalid on 2021/09/13 17:50
android-5-15 BUG: soft lockup in vfs_fallocate 4 107d 147d 0/2 auto-obsoleted due to no activity on 2024/10/05 14:54

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P12792/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=84809, q=578 ncpus=2)
task:syz-executor.4  state:R  running task     stack:26000 pid:12792 tgid:12790 ppid:11281  flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0xf15/0x5d00 kernel/sched/core.c:6745
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7067
 irqentry_exit+0x36/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x1f2/0x560 kernel/locking/lockdep.c:5722
Code: c1 05 3a af 96 7e 83 f8 01 0f 85 ea 02 00 00 9c 58 f6 c4 02 0f 85 d5 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24
RSP: 0018:ffffc900033c6f70 EFLAGS: 00000206
RAX: dffffc0000000000 RBX: 1ffff92000678df0 RCX: 000000007a8c667b
RDX: 0000000000000001 RSI: ffffffff8b2cb260 RDI: ffffffff8b8ff400
RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff284cc58
R10: ffffffff942662c7 R11: 0000000000000004 R12: 0000000000000000
R13: 0000000000000000 R14: ffffffff8dbb1920 R15: 0000000000000000
 rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
 rcu_read_lock include/linux/rcupdate.h:781 [inline]
 ext4_get_group_info+0x126/0x430 fs/ext4/balloc.c:336
 ext4_mb_load_buddy_gfp+0xc9/0xe90 fs/ext4/mballoc.c:1597
 ext4_mb_load_buddy fs/ext4/mballoc.c:1733 [inline]
 ext4_mb_find_by_goal+0x23b/0xd90 fs/ext4/mballoc.c:2346
 ext4_mb_regular_allocator+0x23f/0x3f60 fs/ext4/mballoc.c:2818
 ext4_mb_new_blocks+0x2830/0x4e40 fs/ext4/mballoc.c:6219
 ext4_ext_map_blocks+0x1c24/0x5cd0 fs/ext4/extents.c:4318
 ext4_map_blocks+0x61d/0x17d0 fs/ext4/inode.c:623
 ext4_alloc_file_blocks.isra.0+0x2dc/0xb90 fs/ext4/extents.c:4495
 ext4_fallocate+0x4dc/0x3f00 fs/ext4/extents.c:4792
 vfs_fallocate+0x4b8/0xfb0 fs/open.c:330
 ioctl_preallocate+0x1a8/0x220 fs/ioctl.c:291
 file_ioctl fs/ioctl.c:331 [inline]
 do_vfs_ioctl+0x16da/0x1ad0 fs/ioctl.c:886
 __do_sys_ioctl fs/ioctl.c:905 [inline]
 __se_sys_ioctl fs/ioctl.c:893 [inline]
 __x64_sys_ioctl+0x116/0x220 fs/ioctl.c:893
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7facb027d0a9
RSP: 002b:00007facb10a90c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007facb03b4050 RCX: 00007facb027d0a9
RDX: 0000000020000540 RSI: 0000000040305828 RDI: 0000000000000004
RBP: 00007facb02ec074 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007facb03b4050 R15: 00007ffcc8a80ed8
 </TASK>
rcu: rcu_preempt kthread starved for 10047 jiffies! g84809 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
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:27680 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0xf15/0x5d00 kernel/sched/core.c:6745
 __schedule_loop kernel/sched/core.c:6822 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6837
 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2000
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2202
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.10.0-rc4-syzkaller-00164-g66cc544fd75c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline]
RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:72 [inline]
RIP: 0010:acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:113
Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 65 48 8b 05 68 83 1c 75 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 38 dd b3 00 fb f4 <fa> c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8d807d70 EFLAGS: 00000246
RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8ae738b9
RDX: 0000000000000001 RSI: ffff88801ae88800 RDI: ffff88801ae88864
RBP: ffff88801ae88864 R08: 0000000000000001 R09: ffffed1017246fdd
R10: ffff8880b9237eeb R11: 0000000000000000 R12: ffff888017b97800
R13: ffffffff8e742420 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efd397861f8 CR3: 000000004ace4000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:707
 cpuidle_enter_state+0x85/0x500 drivers/cpuidle/cpuidle.c:267
 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388
 cpuidle_idle_call kernel/sched/idle.c:236 [inline]
 do_idle+0x313/0x3f0 kernel/sched/idle.c:332
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430
 rest_init+0x16b/0x2b0 init/main.c:747
 start_kernel+0x3df/0x4c0 init/main.c:1103
 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507
 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488
 common_startup_64+0x13e/0x148
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/22 02:23 upstream 66cc544fd75c edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in vfs_fallocate
* Struck through repros no longer work on HEAD.