BUG: unable to handle kernel paging request in srcu_invoke_callbacks

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: cbb104f9 Merge branch 'sched-urgent-for-linus' of git://gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16d0a25ae00000
kernel config: https://syzkaller.appspot.com/x/.config?x=1aab6d4187ddf667
dashboard link: https://syzkaller.appspot.com/bug?extid=26fc28fc92de63bad5d7
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
userspace arch: i386

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+26fc28...@syzkaller.appspotmail.com

BUG: unable to handle page fault for address: ffffc90005be4c78
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD aa54f067 P4D aa54f067 PUD aa550067 PMD 9c5ec067 PTE 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 14686 Comm: kworker/0:6 Not tainted 5.4.0-rc7+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: rcu_gp srcu_invoke_callbacks
RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline]
RIP: 0010:rcu_seq_current kernel/rcu/rcu.h:99 [inline]
RIP: 0010:srcu_invoke_callbacks+0xf4/0x360 kernel/rcu/srcutree.c:1169
Code: ff 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 49 02
00 00 48 8b 85 50 ff ff ff 4c 8d ab 40 ff ff ff 4c 89 ef <48> 8b b0 28 04
00 00 e8 e0 86 01 00 48 8d 43 b0 48 89 c2 48 89 85
RSP: 0018:ffff888067ddfc68 EFLAGS: 00010046
RAX: ffffc90005be4850 RBX: ffff8880ae800138 RCX: ffffffff815a6e2a
RDX: 1ffff92000b7c98f RSI: 0000000000000004 RDI: ffff8880ae800078
RBP: ffff888067ddfd30 R08: 0000000000000004 R09: ffffed100cfbbf7b
R10: ffffed100cfbbf7a R11: 0000000000000003 R12: ffff888067ddfca8
R13: ffff8880ae800078 R14: ffff8880ae800040 R15: ffffc90005be4850
FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc90005be4c78 CR3: 00000000a9baf000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
worker_thread+0x98/0xe40 kernel/workqueue.c:2415
kthread+0x361/0x430 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Modules linked in:
CR2: ffffc90005be4c78
---[ end trace a35f045159a36be7 ]---
RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline]
RIP: 0010:rcu_seq_current kernel/rcu/rcu.h:99 [inline]
RIP: 0010:srcu_invoke_callbacks+0xf4/0x360 kernel/rcu/srcutree.c:1169
Code: ff 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 49 02
00 00 48 8b 85 50 ff ff ff 4c 8d ab 40 ff ff ff 4c 89 ef <48> 8b b0 28 04
00 00 e8 e0 86 01 00 48 8d 43 b0 48 89 c2 48 89 85
RSP: 0018:ffff888067ddfc68 EFLAGS: 00010046
RAX: ffffc90005be4850 RBX: ffff8880ae800138 RCX: ffffffff815a6e2a
RDX: 1ffff92000b7c98f RSI: 0000000000000004 RDI: ffff8880ae800078
RBP: ffff888067ddfd30 R08: 0000000000000004 R09: ffffed100cfbbf7b
R10: ffffed100cfbbf7a R11: 0000000000000003 R12: ffff888067ddfca8
R13: ffff8880ae800078 R14: ffff8880ae800040 R15: ffffc90005be4850
FS: 0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffc90005be4c78 CR3: 00000000a9baf000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.