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Date: Thu, 21 Dec 2023 13:58:33 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: David Hildenbrand <david@redhat.com>
Cc: Oliver Sang <oliver.sang@intel.com>, Matthew Wilcox
 <willy@infradead.org>, oe-lkp@lists.linux.dev, lkp@intel.com, Linux Memory
 Management List <linux-mm@kvack.org>, linux-kernel@vger.kernel.org
Subject: Re: [linux-next:master] [mm] bbcbf2a3f0: kernel_BUG_at_mm/memory.c
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On Thu, 21 Dec 2023 12:32:04 +0100 David Hildenbrand <david@redhat.com> wrote:

> On 21.12.23 12:23, Oliver Sang wrote:
> > hi, Andrew Morton,
> > 
> > On Wed, Dec 20, 2023 at 02:11:35PM -0800, Andrew Morton wrote:
> >> On Tue, 19 Dec 2023 23:46:50 +0800 kernel test robot <oliver.sang@intel.com> wrote:
> >>
> >>>
> >>>
> >>> Hello,
> >>>
> >>> kernel test robot noticed "kernel_BUG_at_mm/memory.c" on:
> >>>
> >>> commit: bbcbf2a3f05f74f9d268eab57abbdce6a65a94ad ("mm: convert ksm_might_need_to_copy() to work on folios")
> >>
> >> I assume this is a bisection result, so it's quite repeatable?
> > 
> > yes, we bisect to this commit, it's quite repeatable:
> > 
> > ddd06bb63d9793ce bbcbf2a3f05f74f9d268eab57ab
> > ---------------- ---------------------------
> >         fail:runs  %reproduction    fail:runs
> >             |             |             |
> >             :6          100%           6:6     dmesg.Kernel_panic-not_syncing:Fatal_exception
> >             :6          100%           6:6     dmesg.RIP:do_swap_page
> >             :6          100%           6:6     dmesg.invalid_opcode:#[##]
> >             :6          100%           6:6     dmesg.kernel_BUG_at_mm/memory.c
> > 
> > 
> 
> Can you try with the snipped I sent? Please let me know if you need a 
> full patch for testing purposes.

I think a full patch would be better, please.