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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 21 Jun 2017 13:30:28 -0700
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Subject: Re: [lkp-robot] [mm] 1be7107fbe: kernel_BUG_at_mm/mmap.c
To: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>,
        kernel test robot <xiaolong.ye@intel.com>,
        Michal Hocko <mhocko@suse.com>, LKML <linux-kernel@vger.kernel.org>,
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On Wed, Jun 21, 2017 at 1:27 PM, Oleg Nesterov <oleg@redhat.com> wrote:
>
> Now __do_page_fault() tries to expand the stack itself, and this check
> fails.

But we want that check to trigger and cause the access to fail.
Accessing the stack below the stack pointer is wrong.

Do you have a pointer to the report for this regression? I must have missed it.

                Linus