INFO: rcu detected stall in sys_getrandom

Status: auto-obsoleted due to no activity on 2024/11/15 19:37
Subsystems: mm block cgroups
[Documentation on labels]
First crash: 757d, last: 723d
▶ ▼ Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_getrandom (2) block cgroups 1 2 589d 596d 0/29 auto-obsoleted due to no activity on 2025/03/29 20:22

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P24564/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=227489, q=580 ncpus=2)
task:syz.5.4087      state:R  running task     stack:24504 pid:24564 tgid:24563 ppid:23996  flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x1800/0x4a60 kernel/sched/core.c:6529
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6851
 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:debug_lockdep_rcu_enabled+0x0/0x40 kernel/rcu/update.c:319
Code: 0a 8c 48 c7 c6 20 f8 0a 8c e8 0c 11 9f f5 90 0f 0b 90 90 90 eb c6 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 31 c0 83 3d 3f 35 61 04 00 74 1e 83 3d a6 64 61 04 00
RSP: 0018:ffffc900042b6ee8 EFLAGS: 00000296
RAX: 5e1f6d8cb3917f00 RBX: ffffea0001759300 RCX: 5e1f6d8cb3917f00
RDX: dffffc0000000000 RSI: ffffffff8c0ae6e0 RDI: ffffffff8c606900
RBP: 0000000082000000 R08: ffffffff9372f847 R09: 1ffffffff26e5f08
R10: dffffc0000000000 R11: fffffbfff26e5f09 R12: 0000000000000001
R13: 0000000000000001 R14: ffffffff82060590 R15: 0000000000000000
 rcu_read_lock include/linux/rcupdate.h:839 [inline]
 page_ext_get+0x46/0x2a0 mm/page_ext.c:535
 __page_table_check_zero+0xb1/0x350 mm/page_table_check.c:148
 page_table_check_alloc include/linux/page_table_check.h:33 [inline]
 post_alloc_hook+0x206/0x230 mm/page_alloc.c:1494
 prep_new_page mm/page_alloc.c:1501 [inline]
 get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3442
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4700
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2263
 folio_alloc_mpol_noprof mm/mempolicy.c:2281 [inline]
 vma_alloc_folio_noprof+0x12e/0x230 mm/mempolicy.c:2312
 folio_prealloc+0x31/0x170
 alloc_anon_folio mm/memory.c:4498 [inline]
 do_anonymous_page mm/memory.c:4555 [inline]
 do_pte_missing mm/memory.c:3945 [inline]
 handle_pte_fault+0x2530/0x6eb0 mm/memory.c:5522
 __handle_mm_fault mm/memory.c:5665 [inline]
 handle_mm_fault+0x1029/0x1980 mm/memory.c:5833
 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline]
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x2b9/0x8c0 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:copy_user_generic arch/x86/include/asm/uaccess_64.h:110 [inline]
RIP: 0010:raw_copy_to_user arch/x86/include/asm/uaccess_64.h:131 [inline]
RIP: 0010:copy_to_user_iter lib/iov_iter.c:25 [inline]
RIP: 0010:iterate_ubuf include/linux/iov_iter.h:29 [inline]
RIP: 0010:iterate_and_advance2 include/linux/iov_iter.h:245 [inline]
RIP: 0010:iterate_and_advance include/linux/iov_iter.h:271 [inline]
RIP: 0010:_copy_to_iter+0x266/0x1960 lib/iov_iter.c:185
Code: 82 25 03 00 00 e8 ea 12 e5 fc 4c 8b 7c 24 78 4c 89 ff 48 8b 5c 24 18 89 de e8 66 5c 4c fd 0f 01 cb 4c 89 ef 48 89 d9 4c 89 fe <f3> a4 0f 1f 00 0f 01 ca 48 29 cb 48 89 5c 24 18 49 bd 00 00 00 00
RSP: 0018:ffffc900042b7b00 EFLAGS: 00050256
RAX: ffffffff84ae7801 RBX: 0000000000000040 RCX: 0000000000000040
RDX: 0000000000000000 RSI: ffffc900042b7d40 RDI: 00000000204e4000
RBP: ffffc900042b7c70 R08: ffffc900042b7d7f R09: 1ffff92000856faf
R10: dffffc0000000000 R11: fffff52000856fb0 R12: 1ffff92000856fc9
R13: 00000000204e4000 R14: ffffc900042b7e48 R15: ffffc900042b7d40
 copy_to_iter include/linux/uio.h:196 [inline]
 get_random_bytes_user+0x1e5/0x420 drivers/char/random.c:464
 __do_sys_getrandom drivers/char/random.c:1406 [inline]
 __se_sys_getrandom drivers/char/random.c:1380 [inline]
 __x64_sys_getrandom+0x152/0x250 drivers/char/random.c:1380
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5fcf779e79
RSP: 002b:00007f5fd04e8038 EFLAGS: 00000246 ORIG_RAX: 000000000000013e
RAX: ffffffffffffffda RBX: 00007f5fcf915f80 RCX: 00007f5fcf779e79
RDX: 0000000000000000 RSI: 412269194f7c77a1 RDI: 0000000020000340
RBP: 00007f5fcf7e7916 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f5fcf915f80 R15: 00007fffdaa574b8
 </TASK>
rcu: rcu_preempt kthread starved for 10555 jiffies! g227489 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:25392 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x1800/0x4a60 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236
 kthread+0x2f2/0x390 kernel/kthread.c:389
 ret_from_fork+0x4d/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 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.11.0-rc3-syzkaller-00279-ge5fa841af679 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
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:92 [inline]
RIP: 0010:acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:112
Code: 90 90 90 90 90 90 90 90 90 65 48 8b 04 25 40 d7 03 00 48 f7 00 08 00 00 00 75 10 eb 07 0f 00 2d 95 4b b3 00 f3 0f 1e fa fb f4 <fa> e9 d4 6f 39 00 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90
RSP: 0018:ffffffff8e607ca8 EFLAGS: 00000246
RAX: ffffffff8e694680 RBX: ffff88801ba85864 RCX: 0000000000d04eb1
RDX: 0000000000000001 RSI: ffff88801ba85800 RDI: ffff88801ba85864
RBP: 000000000003a6b8 R08: ffff8880b9237c7b R09: 1ffff11017246f8f
R10: dffffc0000000000 R11: ffffffff8bb6cce0 R12: ffff88801a3dc800
R13: 0000000000000000 R14: 0000000000000001 R15: ffffffff8f0dd240
FS:  0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f190f99b241 CR3: 000000002028c000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 acpi_idle_enter+0xe4/0x140 drivers/acpi/processor_idle.c:702
 cpuidle_enter_state+0x114/0x480 drivers/cpuidle/cpuidle.c:267
 cpuidle_enter+0x5d/0xa0 drivers/cpuidle/cpuidle.c:388
 call_cpuidle kernel/sched/idle.c:155 [inline]
 cpuidle_idle_call kernel/sched/idle.c:230 [inline]
 do_idle+0x375/0x5d0 kernel/sched/idle.c:326
 cpu_startup_entry+0x42/0x60 kernel/sched/idle.c:424
 rest_init+0x2dc/0x300 init/main.c:747
 start_kernel+0x47a/0x500 init/main.c:1103
 x86_64_start_reservations+0x2a/0x30 arch/x86/kernel/head64.c:507
 x86_64_start_kernel+0x9f/0xa0 arch/x86/kernel/head64.c:488
 common_startup_64+0x13e/0x147
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/17 19:36 upstream e5fa841af679 dbc93b08 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in sys_getrandom
2024/07/14 04:04 upstream d0d0cd380055 eaeb5c15 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in sys_getrandom
* Struck through repros no longer work on HEAD.