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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: 277d, last: 5d23h
▶ ▼ 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 16d 545d 0/29 upstream: reported C repro on 2024/05/12 09:19
upstream INFO: rcu detected stall in validate_mm (2) mm 1 2 733d 743d 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 395d 462d 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 3 6d00h 52d 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 89d 138d 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): P4272/1:b..l P4686/1:b..l
	(detected by 1, t=10503 jiffies, g=11501, q=108 ncpus=2)
task:syz.3.67        state:R  running task     stack:27584 pid:4686  ppid:4280   flags:0x00004000
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:mte_parent_slot lib/maple_tree.c:-1 [inline]
RIP: 0010:mas_validate_parent_slot lib/maple_tree.c:7037 [inline]
RIP: 0010:mt_validate+0xd6e/0x4c90 lib/maple_tree.c:7240
Code: 84 c0 0f 85 45 30 00 00 8b 1b 4c 89 ee 48 83 e6 02 31 ff e8 d4 64 7b f7 4c 89 e8 48 83 e0 02 0f 84 4b 2f 00 00 b9 03 00 00 00 <83> e3 01 45 89 ee 41 81 e6 fc 00 00 00 49 d3 ee 31 ff 89 de e8 29
RSP: 0018:ffffc90004bdf880 EFLAGS: 00000202
RAX: 0000000000000002 RBX: 000000000000030b RCX: 0000000000000003
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: ffffc90004bdfa50 R08: ffff88802c64d940 R09: 0000000000000003
R10: 0000000000000003 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff888026b86e0e R14: 0000000000000006 R15: 000000000000000b
 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
 ksys_mmap_pgoff+0x516/0x6f0 mm/mmap.c:1482
 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: 0033:0x7f503258f003
RSP: 002b:00007fff88796a18 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000001b2f364000 RCX: 00007f503258f003
RDX: 0000000000000003 RSI: 00000000005c0000 RDI: 0000001b2f364000
RBP: 0000000000600000 R08: 0000000000000004 R09: 0000000000040000
R10: 0000000000100001 R11: 0000000000000246 R12: 000000000000000a
R13: 00000000000927c0 R14: 000000000001f9a6 R15: 00007fff88796d00
 </TASK>
task:udevd           state:R  running task     stack:23040 pid:4272  ppid:3638   flags:0x00004002
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+0x58/0x60 kernel/kcov.c:234
Code: f8 15 00 00 83 fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc 15 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 <c3> 0f 1f 80 00 00 00 00 48 8b 04 24 65 48 8b 15 74 98 81 7e 65 8b
RSP: 0018:ffffc90003cd7800 EFLAGS: 00000293
RAX: ffffffff81aa81ec RBX: ffffea0001dde734 RCX: ffff88807c105940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffc90003cd78a0
RBP: dffffc0000000000 R08: dffffc0000000000 R09: fffff940003bbce7
R10: fffff940003bbce7 R11: 1ffffd40003bbce6 R12: ffffc90003cd78a0
R13: ffffea0001dde700 R14: 0000000000000201 R15: ffffc90003cd78a0
 xas_reload+0x1c/0x470 include/linux/xarray.h:1574
 filemap_get_read_batch+0x2b3/0xa60 mm/filemap.c:2454
 filemap_get_pages mm/filemap.c:2667 [inline]
 filemap_read+0x61a/0x2f80 mm/filemap.c:2759
 blkdev_read_iter+0x3d5/0x500 block/fops.c:614
 call_read_iter include/linux/fs.h:2259 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x434/0x920 fs/read_write.c:470
 ksys_read+0x143/0x240 fs/read_write.c:613
 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: 0033:0x7fc5932a7407
RSP: 002b:00007fffd0d5a3b0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fc593a92880 RCX: 00007fc5932a7407
RDX: 0000000000000200 RSI: 00007fc593a7c000 RDI: 0000000000000009
RBP: 000055c17693cf80 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000018
R13: 0000000000200000 R14: 000055c17693b778 R15: 00007fc593bb939c
 </TASK>
rcu: rcu_preempt kthread starved for 10568 jiffies! g11501 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:27392 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:2167
 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: 1 PID: 4675 Comm: syz.0.63 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 8e 8f 41 f7 48 89 df e8 e6 54 42 f7 e8 31 48 65 f7 fb bf 01 00 00 00 <e8> 76 cd 35 f7 65 8b 05 f7 84 e0 75 85 c0 74 02 5b c3 e8 44 96 de
RSP: 0018:ffffc90004b7fb98 EFLAGS: 00000282
RAX: 67ebe1a702669500 RBX: ffff888023c35c80 RCX: 67ebe1a702669500
RDX: dffffc0000000000 RSI: ffffffff8a8c0580 RDI: 0000000000000001
RBP: ffff888023c36118 R08: dffffc0000000000 R09: ffffed1004786b91
R10: ffffed1004786b91 R11: 1ffff11004786b90 R12: 1ffff11004786c23
R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000
FS:  00007f1a9fe996c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc593a7d000 CR3: 0000000054b2b000 CR4: 00000000003506e0
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: 0033:0x7f1a9ef8efc7
Code: ff ff 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
RSP: 002b:00007f1a9fe990e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f1a9f1e5fa8 RCX: 00007f1a9ef8efc9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f1a9f1e5fa8
RBP: 00007f1a9f1e5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1a9f1e6038 R14: 00007ffd4a07eeb0 R15: 00007ffd4a07ef98
 </TASK>

Crashes (19):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/02 17:41 linux-6.1.y f6e38ae624cf 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
2025/11/02 09:31 linux-6.1.y f6e38ae624cf 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in validate_mm
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.