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Jones" To: Johannes Weiner Cc: Chengming Zhou , Nhat Pham , Christian Heusel , Seth Jennings , Dan Streetman , Vitaly Wool , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, David Runge , Mark W , regressions@lists.linux.dev, Yosry Ahmed Subject: Re: [REGRESSION] Null pointer dereference while shrinking zswap Message-ID: <20240417150810.GA7636@redhat.com> References: <3iccc6vjl5gminut3lvpl4va2lbnsgku5ei2d7ylftoofy3n2v@gcfdvtsq6dx2> <246c1f4d-af13-40fa-b968-fbaf36b8f91f@linux.dev> <20240417143324.GA1055428@cmpxchg.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240417143324.GA1055428@cmpxchg.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.10 On Wed, Apr 17, 2024 at 10:33:24AM -0400, Johannes Weiner wrote: > I could reproduce the NULL crash locally with cgroup_disable=memory, > the shrinker enabled, and echo 3 >/proc/sys/vm/drop_caches. Can confirm that libguestfs uses cgroup_disable=memory for its appliance (as it saves some RAM and we don't need cgroups). Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-builder quickly builds VMs from scratch http://libguestfs.org/virt-builder.1.html