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Date:   Mon, 11 Oct 2021 11:52:59 +0200
From:   Andrea Righi <andrea.righi@canonical.com>
To:     Dmitry Vyukov <dvyukov@google.com>
Cc:     Marco Elver <elver@google.com>,
        Alexander Potapenko <glider@google.com>,
        kasan-dev@googlegroups.com, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: BUG: soft lockup in __kmalloc_node() with KFENCE enabled
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On Mon, Oct 11, 2021 at 11:23:32AM +0200, Andrea Righi wrote:
...
> > You seem to use the default 20s stall timeout. FWIW syzbot uses 160
> > secs timeout for TCG emulation to avoid false positive warnings:
> > https://github.com/google/syzkaller/blob/838e7e2cd9228583ca33c49a39aea4d863d3e36d/dashboard/config/linux/upstream-arm64-kasan.config#L509
> > There are a number of other timeouts raised as well, some as high as
> > 420 seconds.
> 
> I see, I'll try with these settings and see if I can still hit the soft
> lockup messages.

Still getting soft lockup messages even with the new timeout settings:

[  462.663766] watchdog: BUG: soft lockup - CPU#2 stuck for 430s! [systemd-udevd:168]
[  462.755758] watchdog: BUG: soft lockup - CPU#3 stuck for 430s! [systemd-udevd:171]
[  924.663765] watchdog: BUG: soft lockup - CPU#2 stuck for 861s! [systemd-udevd:168]
[  924.755767] watchdog: BUG: soft lockup - CPU#3 stuck for 861s! [systemd-udevd:171]

-Andrea