From mboxrd@z Thu Jan 1 00:00:00 1970 From: Cornelia Huck Subject: Re: [PATCH 1/5] s390x/mm: cleanup gmap_pte_op_walk() Date: Wed, 20 Dec 2017 17:33:00 +0100 Message-ID: <20171220173300.6f308f2f.cohuck@redhat.com> References: <20171220155300.102321-1-borntraeger@de.ibm.com> <20171220155300.102321-2-borntraeger@de.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20171220155300.102321-2-borntraeger@de.ibm.com> Sender: kvm-owner@vger.kernel.org List-Archive: List-Post: To: Christian Borntraeger Cc: KVM , linux-s390 List-ID: On Wed, 20 Dec 2017 16:52:56 +0100 Christian Borntraeger wrote: > From: David Hildenbrand > > gmap_mprotect_notify() refuses shadow gmaps. Turns out that > a) gmap_protect_range() > b) gmap_read_table() > c) gmap_pte_op_walk() > > Are never called for gmap shadows. And never should be. This dates back > to gmap shadow prototypes where we allowed to call mprotect_notify() on > the gmap shadow (to get notified about the prefix pages getting removed). > This is avoided by always getting notified about any change on the gmap > shadow. > > The only real function for walking page tables on shadow gmaps is > gmap_table_walk(). > > So, essentially, these functions should never get called and > gmap_pte_op_walk() can be cleaned up. Add some checks to callers of > gmap_pte_op_walk(). > > Signed-off-by: David Hildenbrand > Message-Id: <20171110151805.7541-1-david@redhat.com> > Reviewed-by: Janosch Frank > Signed-off-by: Christian Borntraeger > --- > arch/s390/mm/gmap.c | 23 ++++++++--------------- > 1 file changed, 8 insertions(+), 15 deletions(-) Acked-by: Cornelia Huck