Re: WARNING in rds_message_alloc_sgs

[Santosh Shilimkar]

On 10/30/2018 12:28 PM, syzbot wrote:
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit:ÂÂÂ 6201f31a39f8 Add linux-next specific files for 20181030
> git tree:ÂÂÂÂÂÂ linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=1397d06d400000
> kernel config:Â https://syzkaller.appspot.com/x/.config?x=2a22859d870756c1
> dashboard link: 
> https://syzkaller.appspot.com/bug?extid=26de17458aeda9d305d8
> compiler:ÂÂÂÂÂÂ gcc (GCC) 8.0.1 20180413 (experimental)
> syz repro:ÂÂÂÂÂ https://syzkaller.appspot.com/x/repro.syz?x=10bb52eb400000
> C reproducer:ÂÂ https://syzkaller.appspot.com/x/repro.c?x=118bdfc5400000
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+26de17458aeda9d305d8@xxxxxxxxxxxxxxxxxxxxxxxxx
>
> WARNING: CPU: 0 PID: 19789 at net/rds/message.c:316 
> rds_message_alloc_sgs+0x10c/0x160 net/rds/message.c:316
> Kernel panic - not syncing: panic_on_warn set ...
Looks like this kernel build has panic on warn enabled which
triggers panic for " WARN_ON(!nr_pages)" case. Will look into
it. Thanks !!

Regards,
Santosh