syzbot


INFO: rcu detected stall in generic_file_read_iter

Status: upstream: reported C repro on 2020/10/22 13:12
Reported-by: syzbot+7a19f5db69e7dcbe3275@syzkaller.appspotmail.com
First crash: 1273d, last: 1246d
Fix bisection: failed (error log, bisect log)
  
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 INFO: rcu detected stall in generic_file_read_iter C error 1 1258d 1258d 0/1 upstream: reported C repro on 2020/11/06 19:48

Sample crash report:
MINIX-fs: mounting unchecked file system, running fsck is recommended
MINIX-fs: mounting unchecked file system, running fsck is recommended
hrtimer: interrupt took 223516 ns
MINIX-fs: mounting unchecked file system, running fsck is recommended
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=5293, q=39)
rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4295020416-4295009913), jiffies_till_next_fqs=1, root ->qsmask 0x0
syz-executor456 R  running task    24608  8112   8111 0x80000000
Call Trace:
 <IRQ>
 sched_show_task.cold+0x332/0x396 kernel/sched/core.c:5341
 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+0xb37/0xe19 kernel/rcu/tree.c:2682
 update_process_times+0x2a/0xb0 kernel/time/timer.c:1650
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:168
 tick_sched_timer+0xfc/0x290 kernel/time/tick-sched.c:1278
 __run_hrtimer kernel/time/hrtimer.c:1401 [inline]
 __hrtimer_run_queues+0x3f6/0xe60 kernel/time/hrtimer.c:1463
 hrtimer_interrupt+0x32a/0x930 kernel/time/hrtimer.c:1521
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline]
 smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1092
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
 </IRQ>
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:149 [inline]
RIP: 0010:unwind_next_frame+0x23f/0x1c60 arch/x86/kernel/unwind_orc.c:422
Code: 00 00 fc ff df 41 89 f0 4a 8d 3c 85 2c 01 17 8c 49 89 f9 49 c1 e9 03 45 0f b6 0c 11 48 89 fa 83 e2 07 83 c2 03 44 38 ca 7c 32 <45> 84 c9 74 2d 4c 89 44 24 30 48 89 74 24 28 44 89 54 24 20 48 89
RSP: 0018:ffff8880b05869e0 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: 1ffff110160b0d44 RCX: ffffffff817f965b
RDX: 0000000000000007 RSI: 0000000000007f96 RDI: ffffffff8c18ff84
RBP: 0000000000000001 R08: 0000000000007f96 R09: 0000000000000000
R10: 0000000000074071 R11: 0000000000000001 R12: ffff8880b0586b10
R13: ffff8880b0586afd R14: ffff8880b0586b00 R15: ffff8880b0586ac8
 __save_stack_trace+0x9f/0x190 arch/x86/kernel/stacktrace.c:44
 save_stack mm/kasan/kasan.c:448 [inline]
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:553
 kmem_cache_alloc+0x122/0x370 mm/slab.c:3559
 kmem_cache_zalloc include/linux/slab.h:699 [inline]
 alloc_buffer_head+0x20/0x130 fs/buffer.c:3372
 alloc_page_buffers+0x169/0x5c0 fs/buffer.c:830
 create_empty_buffers+0x2c/0x760 fs/buffer.c:1528
 create_page_buffers+0x212/0x350 fs/buffer.c:1645
 block_read_full_page+0xcf/0xd10 fs/buffer.c:2239
 read_pages.isra.0+0x329/0x5d0 mm/readahead.c:133
 __do_page_cache_readahead+0x5c6/0x6c0 mm/readahead.c:211
 ra_submit mm/internal.h:66 [inline]
 ondemand_readahead.isra.0+0x575/0xd40 mm/readahead.c:493
 page_cache_async_readahead mm/readahead.c:575 [inline]
 page_cache_async_readahead+0x406/0x750 mm/readahead.c:548
 generic_file_buffered_read mm/filemap.c:2123 [inline]
 generic_file_read_iter+0x16ac/0x2b60 mm/filemap.c:2385
 call_read_iter include/linux/fs.h:1815 [inline]
 new_sync_read fs/read_write.c:406 [inline]
 __vfs_read+0x518/0x750 fs/read_write.c:418
 integrity_kernel_read+0x147/0x1f0 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+0x512/0x990 security/integrity/ima/ima_crypto.c:458
 ima_collect_measurement+0x4c4/0x570 security/integrity/ima/ima_api.c:231
 process_measurement+0xddd/0x1440 security/integrity/ima/ima_main.c:284
 ima_file_check+0xb9/0x100 security/integrity/ima/ima_main.c:391
 do_last fs/namei.c:3425 [inline]
 path_openat+0x7e4/0x2df0 fs/namei.c:3537
 do_filp_open+0x18c/0x3f0 fs/namei.c:3567
 do_sys_open+0x3b3/0x520 fs/open.c:1085
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x445aa9
Code: 6d cb fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 3b cb fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffdc5896f48 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000445aa9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000200000c0
RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000004
R13: 0000000000000003 R14: 0000000000000003 R15: 0000000000000004
rcu: rcu_preempt kthread starved for 10575 jiffies! g5293 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29208    10      2 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_timeout+0x4cf/0xfe0 kernel/time/timer.c:1825
 rcu_gp_kthread+0xdad/0x21c0 kernel/rcu/tree.c:2202
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/11/18 12:28 linux-4.19.y 31acccdc8774 09323409 .config console log report syz C ci2-linux-4-19
2020/10/22 17:31 linux-4.19.y ad326970d25c be6b1582 .config console log report syz C ci2-linux-4-19
2020/10/22 13:11 linux-4.19.y ad326970d25c be6b1582 .config console log report info ci2-linux-4-19
* Struck through repros no longer work on HEAD.