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INFO: rcu detected stall in blk_trace_ioctl (3)

Status: auto-obsoleted due to no activity on 2026/03/23 08:51
Subsystems: mm
[Documentation on labels]
First crash: 121d, last: 121d
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
85a02be1-4295-4dc3-b0d5-5bfbf5bc0e0c repro INFO: rcu detected stall in blk_trace_ioctl (3) 2026/03/10 03:34 2026/03/10 03:34 2026/03/10 04:00 6972f30219093b03bcc1a54487e12a7097245c01
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in blk_trace_ioctl 1 1 612d 612d 0/3 auto-obsoleted due to no activity on 2024/11/26 21:08
upstream INFO: rcu detected stall in blk_trace_ioctl mm 1 1 493d 493d 0/29 auto-obsoleted due to no activity on 2025/03/15 16:25
upstream INFO: rcu detected stall in blk_trace_ioctl (2) mm 1 1 362d 362d 0/29 auto-obsoleted due to no activity on 2025/07/25 08:11

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:1b, vlan:0)
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P20735/1:b..l
rcu: 	(detected by 0, t=10502 jiffies, g=137877, q=656 ncpus=1)
task:syz.6.2974      state:R  running task     stack:27552 pid:20735 tgid:20728 ppid:16354  task_flags:0x400040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1139/0x6150 kernel/sched/core.c:6863
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
 irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__page_table_check_zero+0x20f/0x4a0 mm/page_table_check.c:143
Code: 89 d8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 68 02 00 00 44 8b 2b 31 ff 44 89 ee e8 2a be 8a ff 45 85 ed 0f 85 2e 01 00 00 <e8> 7c c3 8a ff 4c 8d 6b 04 be 04 00 00 00 4c 89 ef e8 5b ad f3 ff
RSP: 0018:ffffc9000bc5f178 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffff88801cd940f8 RCX: ffffffff82339516
RDX: ffff888035db3d00 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: ffff888035db4830 R12: ffff88801cd940b0
R13: 0000000000000000 R14: 0000000000000000 R15: dffffc0000000000
 page_table_check_alloc include/linux/page_table_check.h:35 [inline]
 post_alloc_hook+0x19e/0x220 mm/page_alloc.c:1847
 prep_new_page mm/page_alloc.c:1854 [inline]
 get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3915
 __alloc_frozen_pages_noprof+0x25f/0x2430 mm/page_alloc.c:5210
 __alloc_pages_noprof mm/page_alloc.c:5244 [inline]
 alloc_pages_bulk_noprof+0x77a/0x1410 mm/page_alloc.c:5164
 ___alloc_pages_bulk mm/kasan/shadow.c:345 [inline]
 __kasan_populate_vmalloc_do mm/kasan/shadow.c:370 [inline]
 __kasan_populate_vmalloc+0xfb/0x220 mm/kasan/shadow.c:424
 kasan_populate_vmalloc include/linux/kasan.h:579 [inline]
 alloc_vmap_area+0x98d/0x2a50 mm/vmalloc.c:2124
 __get_vm_area_node+0x1ca/0x330 mm/vmalloc.c:3219
 get_vm_area_caller+0x71/0xa0 mm/vmalloc.c:3270
 vmap+0x135/0x320 mm/vmalloc.c:3542
 relay_alloc_buf kernel/relay.c:127 [inline]
 relay_create_buf kernel/relay.c:162 [inline]
 relay_open_buf.part.0+0x445/0xc40 kernel/relay.c:390
 relay_open_buf kernel/relay.c:538 [inline]
 relay_open+0x653/0xad0 kernel/relay.c:519
 blk_trace_setup_prepare+0x38e/0x700 kernel/trace/blktrace.c:716
 blk_trace_setup+0x1c5/0x3b0 kernel/trace/blktrace.c:789
 blk_trace_ioctl+0x2ce/0x300 kernel/trace/blktrace.c:935
 blkdev_ioctl+0x1fa/0x6e0 block/ioctl.c:781
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f188b98f7c9
RSP: 002b:00007f188c766038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f188bbe6270 RCX: 00007f188b98f7c9
RDX: 0000200000000240 RSI: 00000000c0481273 RDI: 0000000000000003
RBP: 00007f188ba13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f188bbe6308 R14: 00007f188bbe6270 R15: 00007ffc328993d8
 </TASK>
net_ratelimit: 7106 callbacks suppressed
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, 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:1b, 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:1b, 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:1b, vlan:0)
net_ratelimit: 7661 callbacks suppressed
bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, 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:1b, 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:1b, 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:1b, vlan:0)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/23 08:50 upstream b927546677c8 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: rcu detected stall in blk_trace_ioctl
* Struck through repros no longer work on HEAD.