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Subject: Re: Linux 5.0 regression: BUG: unable to handle kernel paging request
 at ffff888023e26778 RIP: e030:move_page_tables+0x7c1/0xae0
To:     Juergen Gross <jgross@suse.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc:     linux-kernel <linux-kernel@vger.kernel.org>,
        "xen-devel@lists.xenproject.org" <xen-devel@lists.xenproject.org>,
        "Joel Fernandes (Google)" <joel@joelfernandes.org>
References: <39ae9195-cf8f-01fe-df83-38a9a4c52e48@eikelenboom.it>
 <da8badb7-9743-020e-6891-dac944b61ee9@eikelenboom.it>
 <094e923b-4e64-57d8-42c4-6e8890473035@suse.com>
From:   Sander Eikelenboom <linux@eikelenboom.it>
Message-ID: <3be0ee8f-79d4-2a2f-59a5-71f3514d9dbd@eikelenboom.it>
Date:   Sat, 9 Feb 2019 19:51:18 +0100
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On 09/02/2019 19:48, Juergen Gross wrote:
> On 09/02/2019 19:45, Sander Eikelenboom wrote:
>> On 09/02/2019 09:26, Sander Eikelenboom wrote:
>>> L.S.,
>>>
>>>
>>> While testing a Linux 5.0-rc5-ish kernel (pull of yesterday) with some additional patches for
>>> already reported other issues i came across the issue below which i haven't seen with 4.20.x
>>>
>>> I haven't got a reproducer so i might be hard to hit it again, 
>>> system is AMD and this is from the host kernel running under
>>> the Xen hypervisor might it matter.
>>
>>> --
>>>
>>> Sander
>>
>> Hi Boris / Juergen,
>>
>> The commit causing this is:
>> 2c91bd4a4e2e530582d6fd643ea7b86b27907151 mm: speed up mremap by 20x on large regions
>>
>> Since it seems there haven't been any other reports about this .. 
>> could it be this doesn't specifically work well with a Xen PVH dom0 ?
> 
> PVH? Not PV?

Ah sorry, indeed PV !

> 
> Juergen
>