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Date: Wed, 11 Jul 2018 15:40:27 -0700
From: Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [2/2] mm: Drop unneeded ->vm_ops checks
Message-Id: <20180711154027.66dd158b11ab144f2f776221@linux-foundation.org>
In-Reply-To: <20180711221742.GA9360@roeck-us.net>
References: <20180710134821.84709-3-kirill.shutemov@linux.intel.com>
	<20180711221742.GA9360@roeck-us.net>
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To: Guenter Roeck <linux@roeck-us.net>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>, Dmitry Vyukov <dvyukov@google.com>, Oleg Nesterov <oleg@redhat.com>, Andrea Arcangeli <aarcange@redhat.com>, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Stephen Rothwell <sfr@canb.auug.org.au>

On Wed, 11 Jul 2018 15:17:42 -0700 Guenter Roeck <linux@roeck-us.net> wrote:

> On Tue, Jul 10, 2018 at 04:48:21PM +0300, Kirill A. Shutemov wrote:
> > We now have all VMAs with ->vm_ops set and don't need to check it for
> > NULL everywhere.
> > 
> > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> 
> This patch causes two of my qemu tests to fail:
> 	arm:mps2-an385:mps2_defconfig:mps2-an385
> 	xtensa:de212:kc705-nommu:nommu_kc705_defconfig
> 
> Both are nommu configurations.
> 
> Reverting the patch fixes the problem. Bisect log is attached for reference.

Thanks.  And there's the /dev/ion sysbot bug report.

mm-drop-unneeded-vm_ops-checks.patch needs some more work - let's drop it
for now.