Re: [syzbot] BUG: sleeping function called from invalid context in __vmalloc_node_range

[Sebastian Andrzej Siewior]

#syz fix: mm/page_alloc: protect PCP lists with a spinlock
#syz dup: BUG: sleeping function called from invalid context in relay_open_buf

The version of the patch above in next-20220614 is buggy leading to the
report below. The version in next-20220620 is fine. Not sure how to tell
syz bot this…

On 2022-06-18 15:15:20 [-0700], syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    35d872b9ea5b Add linux-next specific files for 20220614
> git tree:       linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=155b0d10080000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=d7bf2236c6bb2403
> dashboard link: https://syzkaller.appspot.com/bug?extid=b577bc624afda52c78de
> compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
> 
> Unfortunately, I don't have any reproducer for this issue yet.
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+b577bc624afda52c78de@xxxxxxxxxxxxxxxxxxxxxxxxx
> 
> BUG: sleeping function called from invalid context at mm/vmalloc.c:2980
…
> Preemption disabled at:
> [<ffffffff81bc76f5>] rmqueue_pcplist mm/page_alloc.c:3813 [inline]
> [<ffffffff81bc76f5>] rmqueue mm/page_alloc.c:3858 [inline]
> [<ffffffff81bc76f5>] get_page_from_freelist+0x455/0x3a20 mm/page_alloc.c:4293

Sebastian