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Date: Mon, 16 Mar 2015 12:12:54 +0100
From: Christian Borntraeger <borntraeger@de.ibm.com>
MIME-Version: 1.0
Subject: Re: [PATCH] mm: trigger panic on bad page or PTE states if panic_on_oops
References: <1426495021-6408-1-git-send-email-borntraeger@de.ibm.com> <20150316110033.GA20546@node.dhcp.inet.fi>
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To: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org

Am 16.03.2015 um 12:00 schrieb Kirill A. Shutemov:
> On Mon, Mar 16, 2015 at 09:37:01AM +0100, Christian Borntraeger wrote:
>> while debugging a memory management problem it helped a lot to
>> get a system dump as early as possible for bad page states.
>>
>> Lets assume that if panic_on_oops is set then the system should
>> not continue with broken mm data structures.
> 
> bed_pte is not an oops.

I know that this is not an oops, but semantically it is like one.  I certainly
want to a way to hard stop the system if something like that happens.

Would something like panic_on_mm_error be better?

> 
> Probably we should consider putting VM_BUG() at the end of these
> functions instead.

That is probably also a workable solution if I can reproduce the issue on
my system, but VM_BUG  defaults to off for many production systems (RHEL, SLES..)

Any other suggestion?

Christian

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