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From: Miklos Szeredi <miklos@szeredi.hu>
Date: Wed, 14 Nov 2018 10:55:50 +0100
Message-ID: <CAJfpeguV6Dwkm-CJieHKZWYK=uw3BYx9nW17KAs8uNJptmnchA@mail.gmail.com>
Subject: Re: overlayfs 4.19: unable to make backup link: Invalid cross-device link
To: Amir Goldstein <amir73il@gmail.com>
Cc: Vivek Goyal <vgoyal@redhat.com>,
        overlayfs <linux-unionfs@vger.kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        =?UTF-8?Q?Maciej_Zi=C4=99ba?= <maciekz82@gmail.com>,
        Theodore Tso <tytso@mit.edu>
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On Wed, Nov 14, 2018 at 10:46 AM, Amir Goldstein <amir73il@gmail.com> wrote:
> On Tue, Oct 30, 2018 at 6:44 AM Amir Goldstein <amir73il@gmail.com> wrote:
>>
> ...
>>
>> So let's try to bisect the offending feature first.
>> If we can't find an offending feature, then there may be an offending
>> commit in 4.18..4.19
>>
>> With kernel 4.19, please try to reproduce after:
>> echo N > /sys/module/overlay/parameters/metacopy
>> and then after:
>
> Miklos, Vivek,
>
> FYI, Maciej has reported that he reproduced the same issue and that
> disabling metacopy fixes the problem.
>
> He offered to provide more information if requested.

Maciej,

Can you please try reproduce with overlay debugging turned on:

    # echo "file fs/overlayfs/* +p" > <debugfs>/dynamic_debug/control

and post the relevant part of dmesg output?

Thanks,
Miklos


>
> Thanks,
> Amir.