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INFO: rcu detected stall in ext4_file_read_iter

Status: upstream: reported C repro on 2019/11/01 11:29
Reported-by: syzbot+acbe23ac696822b44924@syzkaller.appspotmail.com
First crash: 1886d, last: 1513d
Cause bisection: the cause commit could be any of (bisect log):
  8ec426c7019e lustre: don't set f_version in ll_readdir
  ac0bf025d2c0 ima: Use i_version only when filesystem supports it
  7a11ac289c43 ntfs: remove i_version handling
   
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in ext4_file_read_iter mm cgroups 2 1777d 1858d 0/28 auto-closed as invalid on 2020/05/17 22:01
upstream INFO: rcu detected stall in ext4_file_read_iter (2) kasan mm 1 851d 851d 0/28 auto-obsoleted due to no activity on 2022/11/29 18:58
▶ ▼ Fix bisection attempts (13)
Created Duration User Patch Repo Result
2020/12/08 15:16 20m bisect fix linux-4.19.y error job log
2020/11/08 14:46 29m bisect fix linux-4.19.y OK (0) job log log
2020/10/09 14:17 28m bisect fix linux-4.19.y OK (0) job log log
2020/09/09 12:11 34m bisect fix linux-4.19.y OK (0) job log log
2020/08/10 11:30 28m bisect fix linux-4.19.y OK (0) job log log
2020/07/11 10:43 32m bisect fix linux-4.19.y OK (0) job log log
2020/06/11 08:46 31m bisect fix linux-4.19.y OK (0) job log log
2020/05/12 08:12 33m bisect fix linux-4.19.y OK (0) job log log
2020/04/12 07:01 30m bisect fix linux-4.19.y OK (0) job log log
2020/03/13 06:31 29m bisect fix linux-4.19.y OK (0) job log log
2020/02/12 06:02 28m bisect fix linux-4.19.y OK (0) job log log
2020/01/13 05:05 27m bisect fix linux-4.19.y OK (0) job log log
2019/12/14 04:33 27m bisect fix linux-4.19.y OK (0) job log log

Sample crash report:
audit: type=1800 audit(1572603122.582:46): pid=7578 uid=0 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 op=collect_data cause=failed comm="syz-executor017" name="bus" dev="sda1" ino=2233 res=0
audit: type=1800 audit(1572603122.602:47): pid=7580 uid=0 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 op=collect_data cause=failed comm="syz-executor017" name="bus" dev="sda1" ino=2233 res=0
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=5309, q=117)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4295043461-4295032959), jiffies_till_next_fqs=1, root ->qsmask 0x0
syz-executor017 R  running task    25144  7615   7519 0x80000000
Call Trace:
 <IRQ>
 sched_show_task kernel/sched/core.c:5338 [inline]
 sched_show_task.cold+0x2ee/0x35d kernel/sched/core.c:5313
 print_other_cpu_stall kernel/rcu/tree.c:1430 [inline]
 check_cpu_stall kernel/rcu/tree.c:1557 [inline]
 __rcu_pending kernel/rcu/tree.c:3293 [inline]
 rcu_pending kernel/rcu/tree.c:3336 [inline]
 rcu_check_callbacks.cold+0xaa1/0xd90 kernel/rcu/tree.c:2682
 update_process_times+0x32/0x80 kernel/time/timer.c:1638
 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:164
 tick_sched_timer+0x47/0x130 kernel/time/tick-sched.c:1274
 __run_hrtimer kernel/time/hrtimer.c:1398 [inline]
 __hrtimer_run_queues+0x33b/0xdc0 kernel/time/hrtimer.c:1460
 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1518
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline]
 smp_apic_timer_interrupt+0x111/0x550 arch/x86/kernel/apic/apic.c:1092
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:893
 </IRQ>
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:23 [inline]
RIP: 0010:do_memsw_account mm/memcontrol.c:100 [inline]
RIP: 0010:mem_cgroup_commit_charge+0x1ba/0x4a0 mm/memcontrol.c:6045
Code: 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 5a 02 00 00 48 83 3d ab 2b cb 06 00 0f 84 e2 01 00 00 fb 66 0f 1f 44 00 00 <0f> 1f 44 00 00 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 dd
RSP: 0018:ffff8880a9a3ea28 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff10e48cb RBX: 0000000000000000 RCX: 1ffff11012df7554
RDX: dffffc0000000000 RSI: ffff888096fbaa80 RDI: ffff888096fbaa7c
RBP: ffff8880a9a3ea60 R08: ffffea00011bf908 R09: ffff888096fbaaa0
R10: 0000000000000000 R11: 0000000000000000 R12: ffffea00011bf900
R13: ffff8880aa1c6c00 R14: 0000000000000000 R15: 0000000000000001
 __add_to_page_cache_locked+0x6ef/0xc20 mm/filemap.c:889
 add_to_page_cache_lru+0x1c9/0x860 mm/filemap.c:927
 ext4_mpage_readpages+0x414/0x1ae0 fs/ext4/readpage.c:133
 ext4_readpages+0xda/0x120 fs/ext4/inode.c:3355
 read_pages+0x101/0x530 mm/readahead.c:123
 __do_page_cache_readahead+0x626/0x720 mm/readahead.c:211
 ra_submit mm/internal.h:66 [inline]
 ondemand_readahead+0x543/0xcd0 mm/readahead.c:493
 page_cache_async_readahead mm/readahead.c:575 [inline]
 page_cache_async_readahead+0x401/0x790 mm/readahead.c:548
 generic_file_buffered_read mm/filemap.c:2122 [inline]
 generic_file_read_iter+0x188d/0x2ac0 mm/filemap.c:2384
 ext4_file_read_iter+0x180/0x3c0 fs/ext4/file.c:77
 call_read_iter include/linux/fs.h:1814 [inline]
 new_sync_read fs/read_write.c:406 [inline]
 __vfs_read+0x584/0x800 fs/read_write.c:418
 integrity_kernel_read+0x14a/0x200 security/integrity/iint.c:200
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:364 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:393 [inline]
 ima_calc_file_hash+0x510/0x970 security/integrity/ima/ima_crypto.c:458
 ima_collect_measurement+0x50f/0x5c0 security/integrity/ima/ima_api.c:231
 process_measurement+0xeca/0x1560 security/integrity/ima/ima_main.c:284
 ima_file_check+0xc5/0x110 security/integrity/ima/ima_main.c:391
 do_last fs/namei.c:3422 [inline]
 path_openat+0x1130/0x45e0 fs/namei.c:3534
 do_filp_open+0x1a1/0x280 fs/namei.c:3564
 do_sys_open+0x3fe/0x550 fs/open.c:1088
 __do_sys_open fs/open.c:1106 [inline]
 __se_sys_open fs/open.c:1101 [inline]
 __x64_sys_open+0x7e/0xc0 fs/open.c:1101
 do_syscall_64+0xfd/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4478d9
Code: e8 8c e7 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f596a372ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00000000006dcc28 RCX: 00000000004478d9
RDX: 0000000000000000 RSI: 0000000000141042 RDI: 0000000020000100
RBP: 00000000006dcc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dcc2c
R13: 00007ffd3f94f80f R14: 00007f596a3739c0 R15: 00000000006dcc2c
rcu: rcu_preempt kthread starved for 10502 jiffies! g5309 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29424    10      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2826 [inline]
 __schedule+0x866/0x1dc0 kernel/sched/core.c:3515
 schedule+0x92/0x1c0 kernel/sched/core.c:3559
 schedule_timeout+0x4db/0xfc0 kernel/time/timer.c:1806
 rcu_gp_kthread+0xd5c/0x2190 kernel/rcu/tree.c:2202
 kthread+0x354/0x420 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/11/01 10:28 linux-4.19.y ef244c308885 a41ca8fa .config console log report syz C ci2-linux-4-19
* Struck through repros no longer work on HEAD.