On 2019/01/03 2:06, Tetsuo Handa wrote:

On 2018/12/31 17:24, Dmitry Vyukov wrote:

quoted

quoted

quoted

Since this involves OOMs and looks like a one-off induced memory corruption:

#syz dup: kernel panic: corrupted stack end in wb_workfn

Why?

RCU stall in this case is likely to be latency caused by flooding of printk().

Just a hypothesis. OOMs lead to arbitrary memory corruptions, so can
cause stalls as well. But can be what you said too. I just thought
that cleaner dashboard is more useful than a large assorted pile of
crashes. If you think it's actionable in some way, feel free to undup.

We don't know why bpf tree is hitting this problem.
Let's continue monitoring this problem.

#syz undup

A report at 2019/01/05 10:08 from "no output from test machine (2)"
( https://syzkaller.appspot.com/text?tag=CrashLog&x=1700726f400000 )
says that there are flood of memory allocation failure messages.
Since continuous memory allocation failure messages itself is not
recognized as a crash, we might be misunderstanding that this problem
is not occurring recently. It will be nice if we can run testcases
which are executed on bpf-next tree.