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Date:   Wed, 28 Apr 2021 04:32:44 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     kernel test robot <oliver.sang@intel.com>
Cc:     LKML <linux-kernel@vger.kernel.org>, linux-fsdevel@vger.kernel.org,
        lkp@lists.01.org, lkp@intel.com
Subject: Re: [iov_iter]  2418c34937: Initiating_system_reboot
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References: <20210428023747.GA13086@xsang-OptiPlex-9020>
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On Wed, Apr 28, 2021 at 10:37:47AM +0800, kernel test robot wrote:
> 
> 
> Greeting,
> 
> FYI, we noticed the following commit (built with gcc-9):
> 
> commit: 2418c34937c42a30ef4bccd923ad664a89e1fbd4 ("iov_iter: optimize iov_iter_advance() for iovec and kvec")
> https://git.kernel.org/cgit/linux/kernel/git/viro/vfs.git untested.iov_iter
> 
> 
> in testcase: boot
> 
> on test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 16G
> 
> caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):

Could you try https://git.kernel.org/cgit/linux/kernel/git/viro/vfs.git for-lkp
on the same test and see what (if anything) gets spewed into dmesg?