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INFO: rcu detected stall in sys_getrandom (2)

Status: auto-obsoleted due to no activity on 2025/03/29 20:22
Subsystems: block cgroups
[Documentation on labels]
First crash: 231d, last: 223d
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in sys_getrandom block cgroups mm 1 2 357d 392d 0/29 auto-obsoleted due to no activity on 2024/11/15 19:37

Sample crash report:
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P18240/1:b..l
rcu: 	(detected by 0, t=10503 jiffies, g=76345, q=604 ncpus=2)
task:syz.1.5204      state:R  running task     stack:24944 pid:18240 tgid:18237 ppid:5824   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1850/0x4c30 kernel/sched/core.c:6756
 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078
 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:lock_is_held_type+0x5/0x190 kernel/locking/lockdep.c:5906
Code: 90 90 eb b5 e8 2c fc ff ff 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 <41> 57 41 56 41 55 41 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00
RSP: 0018:ffffc900052bf3a0 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffff88814d90a000 RCX: 0000000080000000
RDX: ffff888030721e00 RSI: 00000000ffffffff RDI: ffffffff8e96e828
RBP: 0000000000000000 R08: ffffffff84abca19 R09: 1ffffffff2854910
R10: dffffc0000000000 R11: fffffbfff2854911 R12: dffffc0000000000
R13: ffffc900052bf918 R14: ffff888030721e00 R15: dffffc0000000000
 lock_is_held include/linux/lockdep.h:249 [inline]
 task_css include/linux/cgroup.h:434 [inline]
 blkcg_css+0xa2/0x1d0 block/blk-cgroup.c:110
 blk_cgroup_congested+0xbb/0x200 block/blk-cgroup.c:2196
 __folio_throttle_swaprate+0x84/0x1d0 mm/swapfile.c:4018
 folio_throttle_swaprate include/linux/swap.h:646 [inline]
 folio_prealloc+0x107/0x170 mm/memory.c:1071
 alloc_anon_folio mm/memory.c:4752 [inline]
 do_anonymous_page mm/memory.c:4809 [inline]
 do_pte_missing mm/memory.c:3977 [inline]
 handle_pte_fault+0x2c98/0x5ed0 mm/memory.c:5801
 __handle_mm_fault mm/memory.c:5944 [inline]
 handle_mm_fault+0x1106/0x1bb0 mm/memory.c:6112
 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline]
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x2b9/0x8b0 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:126 [inline]
RIP: 0010:raw_copy_to_user arch/x86/include/asm/uaccess_64.h:147 [inline]
RIP: 0010:copy_to_user_iter lib/iov_iter.c:25 [inline]
RIP: 0010:iterate_ubuf include/linux/iov_iter.h:30 [inline]
RIP: 0010:iterate_and_advance2 include/linux/iov_iter.h:300 [inline]
RIP: 0010:iterate_and_advance include/linux/iov_iter.h:328 [inline]
RIP: 0010:_copy_to_iter+0x262/0x1c50 lib/iov_iter.c:185
Code: 53 03 00 00 e8 cf b4 df fc 4c 8b 7c 24 78 4c 89 ff 4c 8b 74 24 40 44 89 f6 e8 fa 1e 46 fd 0f 01 cb 48 89 df 4c 89 f1 4c 89 fe <f3> a4 0f 1f 00 0f 01 ca 49 bf 00 00 00 00 00 fc ff df 49 29 ce 43
RSP: 0018:ffffc900052bfb00 EFLAGS: 00050256
RAX: ffffffff84bfbf01 RBX: 0000000020264000 RCX: 0000000000000040
RDX: 0000000000000000 RSI: ffffc900052bfd40 RDI: 0000000020264000
RBP: ffffc900052bfc70 R08: ffffc900052bfd7f R09: 1ffff92000a57faf
R10: dffffc0000000000 R11: fffff52000a57fb0 R12: 1ffff92000a57fc9
R13: ffffc900052bfe48 R14: 0000000000000040 R15: ffffc900052bfd40
 copy_to_iter include/linux/uio.h:211 [inline]
 get_random_bytes_user+0x1e5/0x420 drivers/char/random.c:472
 __do_sys_getrandom drivers/char/random.c:1414 [inline]
 __se_sys_getrandom drivers/char/random.c:1388 [inline]
 __x64_sys_getrandom+0x152/0x250 drivers/char/random.c:1388
 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: 0033:0x7f92f6b85d29
RSP: 002b:00007f92f7a9a038 EFLAGS: 00000246 ORIG_RAX: 000000000000013e
RAX: ffffffffffffffda RBX: 00007f92f6d75fa0 RCX: 00007f92f6b85d29
RDX: 0000000000000000 RSI: 00000000ffffff9a RDI: 0000000020000240
RBP: 00007f92f6c01b08 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f92f6d75fa0 R15: 00007ffeb6d62ff8
 </TASK>
rcu: rcu_preempt kthread starved for 5681 jiffies! g76345 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:25976 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1850/0x4c30 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6848
 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045
 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247
 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:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 24 Comm: ksoftirqd/1 Not tainted 6.13.0-rc4-syzkaller-00110-g4099a71718b0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:406 [inline]
RIP: 0010:unwind_next_frame+0xc9e/0x22d0 arch/x86/kernel/unwind_orc.c:585
Code: 4d 39 ee 0f 86 8a 0c 00 00 49 8d 45 08 4c 39 e0 0f 86 7d 0c 00 00 4c 39 f0 0f 87 74 0c 00 00 4c 89 ef e8 a5 22 00 00 49 89 c6 <48> bd 00 00 00 00 00 fc ff df 48 8b 44 24 30 80 3c 28 00 48 8b 5c
RSP: 0018:ffffc900001e5f30 EFLAGS: 00000287
RAX: ffffffff8a9cd1eb RBX: ffffc900001e6010 RCX: 1ffff9200003cc00
RDX: ffffffff90aebdba RSI: 0000000000000002 RDI: ffffc900001e6448
RBP: ffffc900001e0000 R08: 0000000000000005 R09: ffffc900001e60f0
R10: dffffc0000000000 R11: ffffffff818b39d0 R12: ffffc900001e8000
R13: ffffc900001e6448 R14: ffffffff8a9cd1eb R15: 1ffff9200003cc02
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055769cd1e950 CR3: 000000002f8c6000 CR4: 0000000000350ef0
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2353 [inline]
 slab_free mm/slub.c:4613 [inline]
 kmem_cache_free+0x195/0x410 mm/slub.c:4715
 skb_ext_del include/linux/skbuff.h:4882 [inline]
 nf_bridge_info_free net/bridge/br_netfilter_hooks.c:156 [inline]
 br_nf_dev_queue_xmit+0x4cb/0x2390 net/bridge/br_netfilter_hooks.c:882
 NF_HOOK+0x702/0x7c0 include/linux/netfilter.h:314
 br_nf_post_routing+0xa20/0xe80 net/bridge/br_netfilter_hooks.c:997
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0xc5/0x220 net/netfilter/core.c:626
 nf_hook include/linux/netfilter.h:269 [inline]
 NF_HOOK+0x2a7/0x460 include/linux/netfilter.h:312
 br_forward_finish+0xd8/0x130 net/bridge/br_forward.c:66
 br_nf_forward_finish+0xb49/0xfb0 net/bridge/br_netfilter_hooks.c:693
 NF_HOOK+0x702/0x7c0 include/linux/netfilter.h:314
 br_nf_forward_ip+0x61e/0x7b0 net/bridge/br_netfilter_hooks.c:747
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0xc5/0x220 net/netfilter/core.c:626
 nf_hook include/linux/netfilter.h:269 [inline]
 NF_HOOK+0x2a7/0x460 include/linux/netfilter.h:312
 __br_forward+0x489/0x660 net/bridge/br_forward.c:115
 deliver_clone net/bridge/br_forward.c:131 [inline]
 maybe_deliver+0xb3/0x150 net/bridge/br_forward.c:190
 br_flood+0x2e4/0x660 net/bridge/br_forward.c:236
 br_handle_frame_finish+0x18ba/0x1fe0 net/bridge/br_input.c:215
 br_nf_hook_thresh+0x474/0x590
 br_nf_pre_routing_finish_ipv6+0xaa0/0xdd0
 NF_HOOK include/linux/netfilter.h:314 [inline]
 br_nf_pre_routing_ipv6+0x379/0x770 net/bridge/br_netfilter_ipv6.c:184
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_bridge_pre net/bridge/br_input.c:277 [inline]
 br_handle_frame+0x9ff/0x1530 net/bridge/br_input.c:424
 __netif_receive_skb_core+0x14ed/0x4690 net/core/dev.c:5566
 __netif_receive_skb_one_core net/core/dev.c:5670 [inline]
 __netif_receive_skb+0x12f/0x650 net/core/dev.c:5785
 process_backlog+0x662/0x15b0 net/core/dev.c:6117
 __napi_poll+0xcd/0x490 net/core/dev.c:6883
 napi_poll net/core/dev.c:6952 [inline]
 net_rx_action+0x89b/0x1240 net/core/dev.c:7074
 handle_softirqs+0x2d6/0x9b0 kernel/softirq.c:561
 run_ksoftirqd+0xca/0x130 kernel/softirq.c:950
 smpboot_thread_fn+0x546/0xa30 kernel/smpboot.c:164
 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>
net_ratelimit: 14553 callbacks suppressed
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
net_ratelimit: 13751 callbacks suppressed
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0)

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/29 20:19 upstream 4099a71718b0 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: rcu detected stall in sys_getrandom
2024/12/22 11:00 upstream 48f506ad0b68 d7f584ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in sys_getrandom
* Struck through repros no longer work on HEAD.