syzbot


INFO: rcu detected stall in generic_file_read_iter

Status: upstream: reported C repro on 2020/11/06 19:48
Reported-by: syzbot+030716d7ed2f273a8ddc@syzkaller.appspotmail.com
First crash: 1319d, last: 1319d
Fix bisection: failed (error log, bisect log)
  
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: rcu detected stall in generic_file_read_iter C error 3 1307d 1334d 0/1 upstream: reported C repro on 2020/10/22 13:12
Last patch testing requests (2)
Created Duration User Patch Repo Result
2023/02/04 21:32 10m retest repro linux-4.14.y report log
2022/09/14 07:27 8m retest repro linux-4.14.y report log

Sample crash report:
MINIX-fs: mounting unchecked file system, running fsck is recommended
MINIX-fs: mounting unchecked file system, running fsck is recommended
MINIX-fs: mounting unchecked file system, running fsck is recommended
hrtimer: interrupt took 25716 ns
INFO: rcu_preempt detected stalls on CPUs/tasks:
	(detected by 0, t=10502 jiffies, g=985, c=984, q=145)
All QSes seen, last rcu_preempt kthread activity 10503 (4294978738-4294968235), jiffies_till_next_fqs=1, root ->qsmask 0x0
syz-executor136 R  running task    25736  7994   7987 0x80000000
Call Trace:
 <IRQ>
 sched_show_task.cold+0x333/0x39a kernel/sched/core.c:5169
 print_other_cpu_stall kernel/rcu/tree.c:1501 [inline]
 check_cpu_stall kernel/rcu/tree.c:1616 [inline]
 __rcu_pending kernel/rcu/tree.c:3390 [inline]
 rcu_pending kernel/rcu/tree.c:3452 [inline]
 rcu_check_callbacks.cold+0xd29/0xd99 kernel/rcu/tree.c:2792
 update_process_times+0x28/0xa0 kernel/time/timer.c:1591
 tick_sched_handle+0x7d/0x150 kernel/time/tick-sched.c:165
 tick_sched_timer+0x92/0x200 kernel/time/tick-sched.c:1223
 __run_hrtimer kernel/time/hrtimer.c:1223 [inline]
 __hrtimer_run_queues+0x30b/0xc80 kernel/time/hrtimer.c:1287
 hrtimer_interrupt+0x1e6/0x5e0 kernel/time/hrtimer.c:1321
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1075 [inline]
 smp_apic_timer_interrupt+0x117/0x5e0 arch/x86/kernel/apic/apic.c:1100
 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:793
 </IRQ>
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x50/0x80 kernel/locking/spinlock.c:200
RSP: 0018:ffff88809d6b71e8 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10
RAX: 1ffffffff11e1233 RBX: ffff88808e3252e8 RCX: 1ffff110169b616d
RDX: dffffc0000000000 RSI: ffff8880b4db0b48 RDI: ffff8880b4db0b44
RBP: ffff88808e3252e8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 1ffff11013ad6e43 R14: 0000000000000000 R15: ffff88808e3252d0
 spin_unlock_irq include/linux/spinlock.h:367 [inline]
 __add_to_page_cache_locked+0x499/0x840 mm/filemap.c:790
 add_to_page_cache_lru+0xcf/0x2b0 mm/filemap.c:830
 read_pages mm/readahead.c:130 [inline]
 __do_page_cache_readahead+0x659/0x940 mm/readahead.c:199
 ra_submit mm/internal.h:66 [inline]
 ondemand_readahead.isra.0+0x514/0xb60 mm/readahead.c:486
 page_cache_async_readahead mm/readahead.c:562 [inline]
 page_cache_async_readahead+0x16e/0x1d0 mm/readahead.c:538
 generic_file_buffered_read mm/filemap.c:2011 [inline]
 generic_file_read_iter+0xea3/0x21c0 mm/filemap.c:2273
 call_read_iter include/linux/fs.h:1772 [inline]
 new_sync_read fs/read_write.c:401 [inline]
 __vfs_read+0x449/0x620 fs/read_write.c:413
 integrity_kernel_read+0x11b/0x1b0 security/integrity/iint.c:199
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:381 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:410 [inline]
 ima_calc_file_hash+0x430/0x830 security/integrity/ima/ima_crypto.c:475
 ima_collect_measurement+0x39d/0x430 security/integrity/ima/ima_api.c:227
 process_measurement+0x78b/0xb20 security/integrity/ima/ima_main.c:264
 do_last fs/namei.c:3435 [inline]
 path_openat+0x10ad/0x2970 fs/namei.c:3569
 do_filp_open+0x179/0x3c0 fs/namei.c:3603
 do_sys_open+0x296/0x410 fs/open.c:1081
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x4456e9
RSP: 002b:00007ffd6e6eaaa8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004456e9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0
RBP: 00000000006d0018 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000001 R11: 0000000000000246 R12: 00000000004027a0
R13: 0000000000402830 R14: 0000000000000000 R15: 0000000000000000
rcu_preempt kthread starved for 10545 jiffies! g985 c984 f0x2 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0
rcu_preempt     R  running task    30008     8      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 schedule_timeout+0x4af/0xe90 kernel/time/timer.c:1754
 rcu_gp_kthread+0xc0a/0x1e60 kernel/rcu/tree.c:2255
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/11/06 19:47 linux-4.14.y 6b6446efedb2 cba33199 .config console log report syz C ci2-linux-4-14
* Struck through repros no longer work on HEAD.