From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53351) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1c6aRP-0003Uo-Td for qemu-devel@nongnu.org; Tue, 15 Nov 2016 04:54:12 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1c6aRM-0005sm-QP for qemu-devel@nongnu.org; Tue, 15 Nov 2016 04:54:11 -0500 Received: from mx1.redhat.com ([209.132.183.28]:45190) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1c6aRM-0005s6-KW for qemu-devel@nongnu.org; Tue, 15 Nov 2016 04:54:08 -0500 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D64739C0D4 for ; Tue, 15 Nov 2016 09:54:07 +0000 (UTC) Date: Tue, 15 Nov 2016 09:54:03 +0000 From: "Dr. David Alan Gilbert" Message-ID: <20161115095403.GD2038@work-vm> References: <1479156950-2517-1-git-send-email-quintela@redhat.com> <1479156950-2517-3-git-send-email-quintela@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1479156950-2517-3-git-send-email-quintela@redhat.com> Subject: Re: [Qemu-devel] [PATCH 2/3] migration: Test for disabled features on reception List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Juan Quintela Cc: qemu-devel@nongnu.org, amit.shah@redhat.com * Juan Quintela (quintela@redhat.com) wrote: > Right now, if we receive a compressed page or a xbzrle page while this > features are disabled, Bad Things (TM) can happen. Just add a test for > them. This confuses me; I didn't think until recently we could guarantee anything about having the capabilities set on the destination side. Until -incoming defer the destination didn't have a way of setting capabilities in a known state before starting the reception. Dave > Signed-off-by: Juan Quintela > --- > migration/ram.c | 23 ++++++++++++++++++++++- > 1 file changed, 22 insertions(+), 1 deletion(-) > > diff --git a/migration/ram.c b/migration/ram.c > index fb9252d..4bb707c 100644 > --- a/migration/ram.c > +++ b/migration/ram.c > @@ -2464,7 +2464,7 @@ static int ram_load_postcopy(QEMUFile *f) > > static int ram_load(QEMUFile *f, void *opaque, int version_id) > { > - int flags = 0, ret = 0; > + int flags = 0, ret = 0, invalid_flags; > static uint64_t seq_iter; > int len = 0; > /* > @@ -2479,6 +2479,15 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id) > ret = -EINVAL; > } > > + invalid_flags = 0; > + > + if (!migrate_use_xbzrle()) { > + invalid_flags |= RAM_SAVE_FLAG_XBZRLE; > + } > + > + if (!migrate_use_compression()) { > + invalid_flags |= RAM_SAVE_FLAG_COMPRESS_PAGE; > + } > /* This RCU critical section can be very long running. > * When RCU reclaims in the code start to become numerous, > * it will be necessary to reduce the granularity of this > @@ -2499,6 +2508,18 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id) > flags = addr & ~TARGET_PAGE_MASK; > addr &= TARGET_PAGE_MASK; > > + if (flags & invalid_flags) { > + if (flags & invalid_flags & RAM_SAVE_FLAG_XBZRLE) { > + error_report("Received an unexpected XBRLE page"); > + } > + if (flags & invalid_flags & RAM_SAVE_FLAG_COMPRESS_PAGE) { > + error_report("Received an unexpected compressed page"); > + } > + > + ret = -EINVAL; > + break; > + } > + > if (flags & (RAM_SAVE_FLAG_COMPRESS | RAM_SAVE_FLAG_PAGE | > RAM_SAVE_FLAG_COMPRESS_PAGE | RAM_SAVE_FLAG_XBZRLE)) { > RAMBlock *block = ram_block_from_stream(f, flags); > -- > 2.7.4 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK