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INFO: rcu detected stall in shmem_fault (2)

Status: upstream: reported on 2024/12/17 16:40
Reported-by: syzbot+ed7102c3fd41447141e8@syzkaller.appspotmail.com
First crash: 202d, last: 7d22h
▶ ▼ Similar bugs (10)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in shmem_fault (4) kernel 1 920d 920d 0/29 auto-obsoleted due to no activity on 2023/04/08 07:17
linux-5.15 INFO: rcu detected stall in shmem_fault (2) 16 1d09h 399d 0/3 upstream: reported on 2024/06/03 20:13
upstream INFO: rcu detected stall in shmem_fault mm 13 2303d 2463d 0/29 closed as dup on 2019/01/02 16:58
linux-6.6 INFO: rcu detected stall in shmem_fault 3 3d12h 21d 0/2 upstream: reported on 2025/06/16 23:06
linux-6.1 INFO: rcu detected stall in shmem_fault 7 331d 396d 0/3 auto-obsoleted due to no activity on 2024/11/18 20:23
upstream INFO: rcu detected stall in shmem_fault (5) cgroups mm 3 690d 710d 23/29 fixed on 2023/10/12 12:48
linux-5.15 INFO: rcu detected stall in shmem_fault 1 675d 675d 0/3 auto-obsoleted due to no activity on 2023/12/11 11:17
upstream INFO: rcu detected stall in shmem_fault (3) fs mm 4 1169d 1169d 0/29 auto-closed as invalid on 2022/06/25 08:10
upstream INFO: rcu detected stall in shmem_fault (2) cgroups mm 1 2043d 2043d 0/29 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in shmem_fault (6) mm C 121 6h15m 292d 0/29 upstream: reported C repro on 2024/09/19 14:28

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4818/1:b..l P4823/1:b..l P4426/1:b..l
	(detected by 0, t=10502 jiffies, g=13301, q=332 ncpus=2)
task:udevd           state:R  running task     stack:24352 pid:4426  ppid:3624   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 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_irq include/linux/spinlock_api_smp.h:160 [inline]
 _raw_spin_unlock_irq+0x3c/0x40 kernel/locking/spinlock.c:202
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 loop_queue_work drivers/block/loop.c:894 [inline]
 loop_queue_rq+0x9d9/0xac0 drivers/block/loop.c:1874
 __blk_mq_issue_directly block/blk-mq.c:2631 [inline]
 __blk_mq_try_issue_directly+0x4ab/0x7a0 block/blk-mq.c:2684
 blk_mq_request_issue_directly block/blk-mq.c:2718 [inline]
 blk_mq_plug_issue_direct+0x233/0x620 block/blk-mq.c:2738
 blk_mq_flush_plug_list+0x7e7/0xd40 block/blk-mq.c:2838
 __blk_flush_plug+0x3c6/0x440 block/blk-core.c:1163
 blk_finish_plug+0x59/0x80 block/blk-core.c:1187
 read_pages+0x646/0x840 mm/readahead.c:184
 page_cache_ra_unbounded+0x690/0x770 mm/readahead.c:270
 do_page_cache_ra mm/readahead.c:300 [inline]
 force_page_cache_ra mm/readahead.c:331 [inline]
 page_cache_sync_ra+0x3d7/0x490 mm/readahead.c:713
 page_cache_sync_readahead include/linux/pagemap.h:1248 [inline]
 filemap_get_pages mm/filemap.c:2665 [inline]
 filemap_read+0x5ff/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: 0033:0x7fa0c26a7407
RSP: 002b:00007fff945f1a30 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007fa0c2d5a880 RCX: 00007fa0c26a7407
RDX: 0000000000000200 RSI: 00007fa0c2d46000 RDI: 0000000000000009
RBP: 0000563a88d0e000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00000000001fea00 R14: 0000563a88d43f68 R15: 00007fa0c2e8139c
 </TASK>
task:syz.0.123       state:R  running task     stack:25248 pid:4823  ppid:4258   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 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:lock_acquire+0x20f/0x490 kernel/locking/lockdep.c:5666
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc9000c8ff4c0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: fef67b24444b0600
RDX: 0000000000000000 RSI: ffffffff8a6c1160 RDI: ffffffff8abf14a0
RBP: ffffc9000c8ff5c8 R08: dffffc0000000000 R09: fffffbfff2117249
R10: fffffbfff2117249 R11: 1ffffffff2117248 R12: 0000000000000000
R13: 1ffff9200191fea4 R14: 0000000000000246 R15: dffffc0000000000
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 mapping_get_entry mm/filemap.c:1878 [inline]
 __filemap_get_folio+0x111/0xdd0 mm/filemap.c:1943
 shmem_get_folio_gfp+0x310/0x3400 mm/shmem.c:1881
 shmem_fault+0x1be/0x7b0 mm/shmem.c:2156
 __do_fault+0x13b/0x4e0 mm/memory.c:4280
 do_read_fault mm/memory.c:4631 [inline]
 do_fault mm/memory.c:4760 [inline]
 handle_pte_fault mm/memory.c:5031 [inline]
 __handle_mm_fault mm/memory.c:5173 [inline]
 handle_mm_fault+0x28ca/0x3e70 mm/memory.c:5294
 faultin_page mm/gup.c:1026 [inline]
 __get_user_pages+0x3ff/0xeb0 mm/gup.c:1250
 populate_vma_page_range+0x214/0x2b0 mm/gup.c:1607
 __mm_populate+0x248/0x370 mm/gup.c:1721
 mm_populate include/linux/mm.h:2826 [inline]
 vm_mmap_pgoff+0x203/0x2b0 mm/util.c:525
 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: 0033:0x7f4bd8f8e929
RSP: 002b:00007f4bd9d99038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f4bd91b5fa0 RCX: 00007f4bd8f8e929
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f4bd9010b39 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f4bd91b5fa0 R15: 00007fff27de7648
 </TASK>
task:syz.3.118       state:R  running task     stack:25696 pid:4818  ppid:4252   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 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_irq include/linux/spinlock_api_smp.h:160 [inline]
 _raw_spin_unlock_irq+0x3c/0x40 kernel/locking/spinlock.c:202
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 loop_queue_work drivers/block/loop.c:894 [inline]
 loop_queue_rq+0x9d9/0xac0 drivers/block/loop.c:1874
 __blk_mq_issue_directly block/blk-mq.c:2631 [inline]
 __blk_mq_try_issue_directly+0x4ab/0x7a0 block/blk-mq.c:2684
 blk_mq_try_issue_directly+0x28/0x1f0 block/blk-mq.c:2708
 blk_mq_submit_bio+0x1221/0x1f80 block/blk-mq.c:3045
 __submit_bio+0x1a7/0x290 block/blk-core.c:591
 __submit_bio_noacct_mq block/blk-core.c:668 [inline]
 submit_bio_noacct_nocheck+0x7b4/0xa70 block/blk-core.c:697
 ntfs_read_block fs/ntfs/aops.c:345 [inline]
 ntfs_read_folio+0x1ffe/0x2980 fs/ntfs/aops.c:436
 filemap_read_folio+0x160/0x760 mm/filemap.c:2490
 do_read_cache_folio+0x2a0/0x760 mm/filemap.c:3627
 do_read_cache_page+0x32/0x220 mm/filemap.c:3669
 read_mapping_page include/linux/pagemap.h:791 [inline]
 ntfs_map_page fs/ntfs/aops.h:75 [inline]
 load_and_init_upcase fs/ntfs/super.c:1678 [inline]
 load_system_files+0x15d3/0x4460 fs/ntfs/super.c:1810
 ntfs_fill_super+0x182a/0x2a60 fs/ntfs/super.c:2892
 mount_bdev+0x287/0x3c0 fs/super.c:1443
 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x24a/0xa40 fs/namespace.c:3058
 do_mount fs/namespace.c:3401 [inline]
 __do_sys_mount fs/namespace.c:3609 [inline]
 __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3586
 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: 0033:0x7fb81b1900ca
RSP: 002b:00007fb81bfd0e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fb81bfd0ef0 RCX: 00007fb81b1900ca
RDX: 0000200000000000 RSI: 0000200000000080 RDI: 00007fb81bfd0eb0
RBP: 0000200000000000 R08: 00007fb81bfd0ef0 R09: 0000000000000802
R10: 0000000000000802 R11: 0000000000000246 R12: 0000200000000080
R13: 00007fb81bfd0eb0 R14: 000000000001ee6e R15: 0000200000000940
 </TASK>
rcu: rcu_preempt kthread starved for 10612 jiffies! g13301 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:27840 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10e9/0x40d0 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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 1 skipped: idling at default_idle+0xb/0x10 arch/x86/kernel/process.c:741
sched: RT throttling activated

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/30 15:56 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 shmem_fault
2025/06/12 14:27 linux-6.1.y 58485ff1a74f 98683f8f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in shmem_fault
2025/05/20 05:39 linux-6.1.y 325285d9fc86 b84f0537 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in shmem_fault
2025/03/22 01:04 linux-6.1.y 344a09659766 c6512ef7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in shmem_fault
2025/03/21 07:31 linux-6.1.y 344a09659766 62330552 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in shmem_fault
2025/03/12 11:58 linux-6.1.y 6ae7ac5c4251 ee70e6db .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in shmem_fault
2025/01/13 20:48 linux-6.1.y c63962be84ef 249ceea9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in shmem_fault
2024/12/17 16:40 linux-6.1.y 52f863f820fd f93b2b55 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: rcu detected stall in shmem_fault
* Struck through repros no longer work on HEAD.