From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58377) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cnNYT-00016W-Am for qemu-devel@nongnu.org; Mon, 13 Mar 2017 06:50:22 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cnNYP-0007RU-CD for qemu-devel@nongnu.org; Mon, 13 Mar 2017 06:50:21 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47720) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cnNYP-0007RN-5X for qemu-devel@nongnu.org; Mon, 13 Mar 2017 06:50:17 -0400 From: Juan Quintela In-Reply-To: <20170309132216.23482-3-dgilbert@redhat.com> (David Alan Gilbert's message of "Thu, 9 Mar 2017 13:22:16 +0000") References: <20170309132216.23482-1-dgilbert@redhat.com> <20170309132216.23482-3-dgilbert@redhat.com> Reply-To: quintela@redhat.com Date: Mon, 13 Mar 2017 11:50:14 +0100 Message-ID: <8760jdh2mx.fsf@secure.mitica> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Qemu-devel] [PATCH v2 2/2] postcopy: Check for shared memory List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Dr. David Alan Gilbert (git)" Cc: qemu-devel@nongnu.org, pbonzini@redhat.com, lvivier@redhat.com, pasic@linux.vnet.ibm.com "Dr. David Alan Gilbert (git)" wrote: > From: "Dr. David Alan Gilbert" > > Postcopy doesn't support migration of RAM shared with another process > yet (we've got a bunch of things to understand). > Check for the case and don't allow postcopy to be enabled. > > Signed-off-by: Dr. David Alan Gilbert > --- > migration/postcopy-ram.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c > index effbeb6..dc80dbb 100644 > --- a/migration/postcopy-ram.c > +++ b/migration/postcopy-ram.c > @@ -95,6 +95,19 @@ static bool ufd_version_check(int ufd) > return true; > } > > +/* Callback from postcopy_ram_supported_by_host block iterator. > + */ > +static int test_range_shared(const char *block_name, void *host_addr, > + ram_addr_t offset, ram_addr_t length, void *opaque) Direct question for the name? ram_range_is_shared? > +{ > + if (qemu_ram_is_shared(qemu_ram_block_by_name(block_name))) { > + error_report("Postcopy on shared RAM (%s) is not yet supported", > + block_name); > + return 1; > + } > + return 0; > +} Wow, we still predate use of bool for questions :-p > + > /* > * Note: This has the side effect of munlock'ing all of RAM, that's > * normally fine since if the postcopy succeeds it gets turned back on at the > @@ -127,6 +140,11 @@ bool postcopy_ram_supported_by_host(void) > goto out; > } > > + /* We don't support postcopy with shared RAM yet */ > + if (qemu_ram_foreach_block(test_range_shared, NULL)) { > + goto out; > + } > + > /* > * userfault and mlock don't go together; we'll put it back later if > * it was enabled. As my comments are only aestetic, Reviewed-by: Juan Quintela