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INFO: rcu detected stall in mmap_pgoff (2)

Status: upstream: reported on 2024/07/04 06:23
Reported-by: syzbot+de84462faf002a8c8dcf@syzkaller.appspotmail.com
First crash: 105d, last: 50d
▶ ▼ Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in mmap_pgoff (5) mm fs 2 448d 478d 0/28 auto-obsoleted due to no activity on 2023/10/25 16:56
linux-4.19 INFO: rcu detected stall in mmap_pgoff syz error 2 1275d 1344d 0/1 upstream: reported syz repro on 2021/02/11 18:33
linux-5.15 INFO: rcu detected stall in mmap_pgoff 1 374d 374d 0/3 auto-obsoleted due to no activity on 2024/01/17 20:08
upstream INFO: rcu detected stall in mmap_pgoff (4) mm 1 575d 575d 0/28 auto-obsoleted due to no activity on 2023/05/21 07:37
upstream INFO: rcu detected stall in mmap_pgoff crypto 3 1068d 1076d 0/28 closed as invalid on 2022/02/08 10:00
upstream INFO: rcu detected stall in mmap_pgoff (3) mm 1 766d 766d 0/28 auto-obsoleted due to no activity on 2022/12/11 19:43
upstream INFO: rcu detected stall in mmap_pgoff (2) kernel 1 965d 965d 0/28 auto-closed as invalid on 2022/05/26 19:52

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7844/1:b..l
	(detected by 1, t=10502 jiffies, g=35853, q=148)
task:syz.1.1092      state:R  running task     stack:25760 pid: 7844 ppid:  7439 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777
 irqentry_exit+0x53/0x80 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:101 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x5f/0x290 mm/kasan/generic.c:189
Code: eb 03 49 b8 00 00 00 00 00 fc ff df 4e 8d 0c 03 4c 8d 54 37 ff 49 c1 ea 03 49 bb 01 00 00 00 00 fc ff df 4f 8d 34 1a 4c 89 f5 <4c> 29 cd 48 83 fd 10 7f 26 48 85 ed 0f 84 3a 01 00 00 49 f7 d2 49
RSP: 0018:ffffc900030975a8 EFLAGS: 00000a07
RAX: ffffffff81a99f01 RBX: 1ffffd40002d5cb8 RCX: ffffffff81a99f83
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffea00016ae5c0
RBP: fffff940002d5cb9 R08: dffffc0000000000 R09: fffff940002d5cb8
R10: 1ffffd40002d5cb8 R11: dffffc0000000001 R12: ffffea00016ae5c0
R13: ffffea00016ae5c8 R14: fffff940002d5cb9 R15: ffffc90003097720
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 PageUptodate include/linux/page-flags.h:536 [inline]
 next_uptodate_page+0x313/0x900 mm/filemap.c:3261
 first_map_page mm/filemap.c:3288 [inline]
 filemap_map_pages+0x2d0/0x15c0 mm/filemap.c:3314
 do_fault_around mm/memory.c:4213 [inline]
 do_read_fault mm/memory.c:4228 [inline]
 do_fault mm/memory.c:4362 [inline]
 handle_pte_fault mm/memory.c:4621 [inline]
 __handle_mm_fault mm/memory.c:4756 [inline]
 handle_mm_fault+0x341b/0x5950 mm/memory.c:4854
 faultin_page mm/gup.c:976 [inline]
 __get_user_pages+0x4ed/0x11d0 mm/gup.c:1197
 populate_vma_page_range+0x215/0x2a0 mm/gup.c:1529
 __mm_populate+0x2a5/0x4a0 mm/gup.c:1638
 mm_populate include/linux/mm.h:2632 [inline]
 vm_mmap_pgoff+0x22b/0x2d0 mm/util.c:556
 ksys_mmap_pgoff+0x13e/0x780 mm/mmap.c:1624
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f74218d3e79
RSP: 002b:00007f741fd50038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f7421a6ff80 RCX: 00007f74218d3e79
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000000020000000
RBP: 00007f742194193e R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f7421a6ff80 R15: 00007ffdfec69cb8
 </TASK>
rcu: rcu_preempt kthread starved for 9900 jiffies! g35853 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:26144 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:108 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:562

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/28 05:11 linux-5.15.y fa93fa65db6e 6c853ff9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in mmap_pgoff
2024/07/04 06:22 linux-5.15.y 4878aadf2d15 f76a75f3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in mmap_pgoff
* Struck through repros no longer work on HEAD.