INFO: rcu detected stall in corrupted (3)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    8c2ffd91 Linux 5.1-rc2
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15099d2b200000
kernel config:  https://syzkaller.appspot.com/x/.config?x=8dcdce25ea72bedf
dashboard link: https://syzkaller.appspot.com/bug?extid=65cecdd27b726c261799
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=17d3c67d200000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=11d4f317200000

Bisection is inconclusive: the bug happens on the oldest tested release.

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=111a358b200000
console output: https://syzkaller.appspot.com/x/log.txt?x=151a358b200000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+65cecdd27b726c261799@xxxxxxxxxxxxxxxxxxxxxxxxx

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P8340
rcu: 	(detected by 1, t=10502 jiffies, g=5905, q=81)
syz-executor586 R  running task    27832  8340   8338 0x00000000
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x817/0x1cc0 kernel/sched/core.c:3518
 preempt_schedule_common+0x4f/0xe0 kernel/sched/core.c:3642
 preempt_schedule+0x4b/0x60 kernel/sched/core.c:3668
 ___preempt_schedule+0x16/0x18
 __sched_setscheduler+0x12fb/0x1e70 kernel/sched/core.c:4398
 sched_setattr kernel/sched/core.c:4440 [inline]
 __do_sys_sched_setattr kernel/sched/core.c:4616 [inline]
 __se_sys_sched_setattr kernel/sched/core.c:4595 [inline]
 __x64_sys_sched_setattr+0x184/0x2b0 kernel/sched/core.c:4595
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4403c9
Code: 76 77 78 5d 20 5b 2d 6c 3c 68 6f 73 74 6c 69 73 74 3e 5d 20 5b 2d 73  
3c 64 6f 6d 61 69 6e 6c 69 73 74 3e 5d 0a 20 20 20 20 20 <20> 20 20 20 20  
20 20 20 20 20 20 5b 2d 66 3c 63 6f 6e 66 66 69 6c
RSP: 002b:00007ffea1a49298 EFLAGS: 00000246 ORIG_RAX: 000000000000013a
RAX: ffffffffffffffda RBX: 00007ffea1a49340 RCX: 00000000004403c9
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000002b80 R09: 0000000000400d10
R10: 000000000000f8f8 R11: 0000000000000246 R12: 0000000000401c90
R13: 0000000000401d20 R14: 0000000000000000 R15: 0000000000000000
syz-executor586 R  running task    27832  8340   8338 0x00000000
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x817/0x1cc0 kernel/sched/core.c:3518
 preempt_schedule_common+0x4f/0xe0 kernel/sched/core.c:3642
 preempt_schedule+0x4b/0x60 kernel/sched/core.c:3668
 ___preempt_schedule+0x16/0x18
 __sched_setscheduler+0x12fb/0x1e70 kernel/sched/core.c:4398
 sched_setattr kernel/sched/core.c:4440 [inline]
 __do_sys_sched_setattr kernel/sched/core.c:4616 [inline]
 __se_sys_sched_setattr kernel/sched/core.c:4595 [inline]
 __x64_sys_sched_setattr+0x184/0x2b0 kernel/sched/core.c:4595
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4403c9
Code: 76 77 78 5d 20 5b 2d 6c 3c 68 6f 73 74 6c 69 73 74 3e 5d 20 5b 2d 73  
3c 64 6f 6d 61 69 6e 6c 69 73 74 3e 5d 0a 20 20 20 20 20 <20> 20 20 20 20  
20 20 20 20 20 20 5b 2d 66 3c 63 6f 6e 66 66 69 6c
RSP: 002b:00007ffea1a49298 EFLAGS: 00000246 ORIG_RAX: 000000000000013a
RAX: ffffffffffffffda RBX: 00007ffea1a49340 RCX: 00000000004403c9
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000002b80 R09: 0000000000400d10
R10: 000000000000f8f8 R11: 0000000000000246 R12: 0000000000401c90
R13: 0000000000401d20 R14: 0000000000000000 R15: 0000000000000000


---
This bug is generated by a bot. It may contain errors.
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For information about bisection process see: https://goo.gl/tpsmEJ#bisection
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches