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INFO: rcu detected stall in validate_mm (2)

Status: upstream: reported on 2025/02/03 21:26
Reported-by: syzbot+022b50cd692aa01556aa@syzkaller.appspotmail.com
First crash: 264d, last: 7h47m
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in validate_mm (3) mm 1 C error 38 2d15h 531d 0/29 upstream: reported C repro on 2024/05/12 09:19
upstream INFO: rcu detected stall in validate_mm (2) mm 1 2 719d 729d 0/29 auto-obsoleted due to no activity on 2024/02/04 15:00
linux-6.1 INFO: rcu detected stall in validate_mm 1 6 382d 448d 0/3 auto-obsoleted due to no activity on 2025/01/16 23:39
linux-6.6 INFO: rcu detected stall in validate_mm origin:lts-only 1 C 2 21d 38d 0/2 upstream: reported C repro on 2025/09/17 06:23
linux-5.15 INFO: rcu detected stall in validate_mm origin:lts-only 1 syz 2 76d 124d 0/3 upstream: reported syz repro on 2025/06/23 12:02

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P41/1:b..l P3637/1:b..l P7461/1:b..l
	(detected by 0, t=10502 jiffies, g=34561, q=195 ncpus=2)
task:sed             state:R  running task     stack:26880 pid:7461  ppid:7460   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:xa_is_internal include/linux/xarray.h:171 [inline]
RIP: 0010:xa_is_node include/linux/xarray.h:1242 [inline]
RIP: 0010:mas_start lib/maple_tree.c:1401 [inline]
RIP: 0010:mt_validate_nulls lib/maple_tree.c:7182 [inline]
RIP: 0010:mt_validate+0x3fc3/0x4c90 lib/maple_tree.c:7247
Code: 85 ff 74 07 e8 5e 3b 7b f7 eb 1f e8 97 70 64 f7 41 89 c7 31 ff 89 c6 e8 ab 3e 7b f7 45 85 ff 0f 84 cb 09 00 00 e8 3d 3b 7b f7 <45> 89 f7 41 83 e7 03 bf 02 00 00 00 4c 89 fe e8 09 3f 7b f7 49 81
RSP: 0018:ffffc900052e7420 EFLAGS: 00000293
RAX: ffffffff8a0597b2 RBX: ffff88801746cb40 RCX: ffff88802acd9dc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900052e75f0 R08: dffffc0000000000 R09: ffffc900052e7510
R10: fffff52000a5cea4 R11: 1ffff92000a5cea2 R12: dffffc0000000000
R13: 1ffff11002e8d968 R14: ffff88801ee7100e R15: 0000000000000001
 validate_mm_mt+0xcd/0x420 mm/mmap.c:295
 validate_mm+0xcc/0x2b0 mm/mmap.c:332
 do_mmap+0xc7/0xfd0 mm/mmap.c:1270
 vm_mmap_pgoff+0x1b2/0x2b0 mm/util.c:520
 elf_map+0xfd/0x2f0 fs/binfmt_elf.c:371
 elf_load+0x8a/0x490 fs/binfmt_elf.c:393
 load_elf_binary+0x106a/0x26d0 fs/binfmt_elf.c:1206
 search_binary_handler fs/exec.c:1764 [inline]
 exec_binprm fs/exec.c:1805 [inline]
 bprm_execve+0xb10/0x18a0 fs/exec.c:1874
 do_execveat_common+0x51b/0x6c0 fs/exec.c:1979
 do_execve fs/exec.c:2053 [inline]
 __do_sys_execve fs/exec.c:2129 [inline]
 __se_sys_execve fs/exec.c:2124 [inline]
 __x64_sys_execve+0x8e/0xa0 fs/exec.c:2124
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fbe190c2107
RSP: 002b:00007ffd3a21d1d8 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 000055bb1a05b078 RCX: 00007fbe190c2107
RDX: 000055bb1a05b0a0 RSI: 000055bb1a05b078 RDI: 000055bb1a05b130
RBP: 000055bb1a05b130 R08: 00007ffd3a222e74 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 000055bb1a05b0a0
R13: 00007fbe19287e8b R14: 000055bb1a05b0a0 R15: 0000000000000000
 </TASK>
task:udevd           state:R  running task     stack:23040 pid:3637  ppid:1      flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6730
 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6754
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0xf6/0x100 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
 __wake_up_common_lock kernel/sched/wait.c:140 [inline]
 __wake_up_sync_key+0x11b/0x180 kernel/sched/wait.c:208
 sock_def_readable+0x15b/0x280 net/core/sock.c:3313
 __netlink_sendskb net/netlink/af_netlink.c:1264 [inline]
 netlink_sendskb+0x97/0x130 net/netlink/af_netlink.c:1270
 netlink_sendmsg+0x89e/0xbc0 net/netlink/af_netlink.c:1872
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x59b/0x970 net/socket.c:2519
 ___sys_sendmsg+0x21c/0x290 net/socket.c:2573
 __sys_sendmsg net/socket.c:2602 [inline]
 __do_sys_sendmsg net/socket.c:2611 [inline]
 __se_sys_sendmsg+0x19e/0x270 net/socket.c:2609
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f7d288a7407
RSP: 002b:00007ffe8b7a7850 EFLAGS: 00000202 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f7d29087880 RCX: 00007f7d288a7407
RDX: 0000000000000000 RSI: 00007ffe8b7a78b0 RDI: 0000000000000004
RBP: 0000560a0a878f90 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000000a7
R13: 0000560a0a8549e0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
task:kworker/u4:2    state:R  running task     stack:22320 pid:41    ppid:2      flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:212
Code: 2e 0f 1f 84 00 00 00 00 00 90 53 48 89 fb e8 17 00 00 00 48 8b 3d d0 9b 9e 0c 48 89 de 5b e9 97 65 4f 00 00 00 cc cc 00 00 cc <48> 8b 04 24 65 48 8b 0d 24 9c 81 7e 65 8b 15 25 9c 81 7e 81 e2 00
RSP: 0018:ffffc90000b27bd8 EFLAGS: 00000202
RAX: 1ffff1100b030301 RBX: 0000000000000001 RCX: ffff88801cec0001
RDX: 0000000000000000 RSI: ffffffff8adef380 RDI: ffffffff8adef340
RBP: fffffffffffffe38 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: dffffc0000000000
R13: ffffffff89e1a74e R14: ffff888058694c80 R15: 0000000000000371
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:409 [inline]
 batadv_nc_worker+0x19c/0x600 net/batman-adv/network-coding.c:719
 process_one_work+0x898/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: rcu_preempt kthread starved for 10588 jiffies! g34561 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:27840 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 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:
CPU: 0 PID: 7454 Comm: syz.0.674 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f5 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 3e 9d 41 f7 48 89 df e8 96 62 42 f7 e8 b1 54 65 f7 fb bf 01 00 00 00 <e8> 46 dd 35 f7 65 8b 05 c7 94 e0 75 85 c0 74 02 5b c3 e8 14 a6 de
RSP: 0018:ffffc900051f7b98 EFLAGS: 00000282
RAX: 87c0adb7f8841600 RBX: ffff88807c4b1bc0 RCX: 87c0adb7f8841600
RDX: dffffc0000000000 RSI: ffffffff8a8c0580 RDI: 0000000000000001
RBP: ffff88807c4b1e58 R08: dffffc0000000000 R09: ffffed100f896379
R10: ffffed100f896379 R11: 1ffff1100f896378 R12: 1ffff1100f8963cb
R13: 0000000000000011 R14: dffffc0000000000 R15: 0000000000000000
FS:  00007f2268ae66c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30a30000 CR3: 0000000066d71000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x1163/0x1350 kernel/signal.c:2874
 arch_do_signal_or_restart+0xb7/0x1240 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f2267b8efc9
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:00007f2268ae60e8 EFLAGS: 00000246
RAX: fffffffffffffffc RBX: 00007f2267de5fa8 RCX: 00007f2267b8efc9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f2267de5fa8
RBP: 00007f2267de5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2267de6038 R14: 00007ffe8b4717d0 R15: 00007ffe8b4718b8
 </TASK>

Crashes (17):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/10/25 20:30 linux-6.1.y 8e6e2188d949 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/10/23 02:40 linux-6.1.y 8e6e2188d949 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/10/22 20:01 linux-6.1.y 8e6e2188d949 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/10/13 05:29 linux-6.1.y 882efbdd9d34 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/10/02 05:23 linux-6.1.y 7b34dc04e4ff 267f56c6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/09/15 23:17 linux-6.1.y 3db754f56897 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/09/15 11:20 linux-6.1.y 3db754f56897 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/09/02 00:24 linux-6.1.y f89b6e15694c 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/09/01 16:18 linux-6.1.y f89b6e15694c 807a3b61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/06/29 05:00 linux-6.1.y 7e69c33e4858 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/06/06 16:20 linux-6.1.y 58485ff1a74f 9fa58bba .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/05/29 00:12 linux-6.1.y da3c5173c55f 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/05/24 07:12 linux-6.1.y da3c5173c55f ed351ea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/05/23 06:13 linux-6.1.y da3c5173c55f fa44301a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/03/08 06:32 linux-6.1.y 6ae7ac5c4251 7e3bd60d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/02/20 15:43 linux-6.1.y 0cbb5f65e52f 50668798 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/02/03 21:26 linux-6.1.y 0cbb5f65e52f a21a8419 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
* Struck through repros no longer work on HEAD.