From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f46.google.com (mail-pa0-f46.google.com [209.85.220.46]) by kanga.kvack.org (Postfix) with ESMTP id DD9646B0038 for ; Fri, 13 Nov 2015 17:58:34 -0500 (EST) Received: by pacej9 with SMTP id ej9so6353718pac.2 for ; Fri, 13 Nov 2015 14:58:34 -0800 (PST) Received: from mail-pa0-x234.google.com (mail-pa0-x234.google.com. [2607:f8b0:400e:c03::234]) by mx.google.com with ESMTPS id ah5si30211496pbd.102.2015.11.13.14.58.34 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 13 Nov 2015 14:58:34 -0800 (PST) Received: by pabfh17 with SMTP id fh17so113395613pab.0 for ; Fri, 13 Nov 2015 14:58:34 -0800 (PST) Date: Fri, 13 Nov 2015 14:58:32 -0800 (PST) From: David Rientjes Subject: Re: [PATCH] mm: Loosen MADV_NOHUGEPAGE to enable Qemu postcopy on s390 In-Reply-To: <1447341516-18076-1-git-send-email-jjherne@linux.vnet.ibm.com> Message-ID: References: <1447341516-18076-1-git-send-email-jjherne@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: "Jason J. Herne" Cc: linux-s390@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org, aarcange@redhat.com, borntraeger@de.ibm.com On Thu, 12 Nov 2015, Jason J. Herne wrote: > MADV_NOHUGEPAGE processing is too restrictive. kvm already disables > hugepage but hugepage_madvise() takes the error path when we ask to turn > on the MADV_NOHUGEPAGE bit and the bit is already on. This causes Qemu's > new postcopy migration feature to fail on s390 because its first action is > to madvise the guest address space as NOHUGEPAGE. This patch modifies the > code so that the operation succeeds without error now. > > Signed-off-by: Jason J. Herne > Reviewed-by: Andrea Arcangeli Acked-by: David Rientjes -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org