On Thu, Mar 14, 2024 at 11:10:12AM -0400, Peter Xu wrote: > On Wed, Mar 13, 2024 at 06:28:24PM -0300, Fabiano Rosas wrote: > > When doing migration using the fd: URI, the incoming migration starts > > before the user has passed the file descriptor to QEMU. This means > > that the checks at migration_channels_and_transport_compatible() > > happen too soon and we need to allow a migration channel of type > > SOCKET_ADDRESS_TYPE_FD even though socket migration is not supported > > with multifd. > > Hmm, bare with me if this is a stupid one.. why the incoming migration can > start _before_ the user passed in the fd? > > IOW, why can't we rely on a single fd_is_socket() check for > SOCKET_ADDRESS_TYPE_FD in transport_supports_multi_channels()? > > > > > The commit decdc76772 ("migration/multifd: Add mapped-ram support to > > fd: URI") was supposed to add a second check prior to starting > > migration to make sure a socket fd is not passed instead of a file fd, > > but failed to do so. > > > > Add the missing verification. > > > > Fixes: decdc76772 ("migration/multifd: Add mapped-ram support to fd: URI") > > Signed-off-by: Fabiano Rosas <faro...@suse.de> > > --- > > migration/fd.c | 8 ++++++++ > > migration/file.c | 7 +++++++ > > 2 files changed, 15 insertions(+) > > > > diff --git a/migration/fd.c b/migration/fd.c > > index 39a52e5c90..c07030f715 100644 > > --- a/migration/fd.c > > +++ b/migration/fd.c > > @@ -22,6 +22,7 @@ > > #include "migration.h" > > #include "monitor/monitor.h" > > #include "io/channel-file.h" > > +#include "io/channel-socket.h" > > #include "io/channel-util.h" > > #include "options.h" > > #include "trace.h" > > @@ -95,6 +96,13 @@ void fd_start_incoming_migration(const char *fdname, > > Error **errp) > > } > > > > if (migrate_multifd()) { > > + if (fd_is_socket(fd)) { > > + error_setg(errp, > > + "Multifd migration to a socket FD is not > > supported"); > > + object_unref(ioc); > > + return; > > + }
And... I just noticed this is forbiding multifd+socket+fd in general? But isn't that the majority of multifd usage when with libvirt over sockets? Shouldn't it about fd's seekable-or-not instead when mapped-ram enabled (IOW, migration_needs_seekable_channel() only)? > > + > > file_create_incoming_channels(ioc, errp); > > } else { > > qio_channel_set_name(ioc, "migration-fd-incoming"); > > diff --git a/migration/file.c b/migration/file.c > > index ddde0ca818..b6e8ba13f2 100644 > > --- a/migration/file.c > > +++ b/migration/file.c > > @@ -15,6 +15,7 @@ > > #include "file.h" > > #include "migration.h" > > #include "io/channel-file.h" > > +#include "io/channel-socket.h" > > #include "io/channel-util.h" > > #include "options.h" > > #include "trace.h" > > @@ -58,6 +59,12 @@ bool file_send_channel_create(gpointer opaque, Error > > **errp) > > int fd = fd_args_get_fd(); > > > > if (fd && fd != -1) { > > + if (fd_is_socket(fd)) { > > + error_setg(errp, > > + "Multifd migration to a socket FD is not > > supported"); > > + goto out; > > + } > > + > > ioc = qio_channel_file_new_dupfd(fd, errp); > > } else { > > ioc = qio_channel_file_new_path(outgoing_args.fname, flags, 0, > > errp); > > -- > > 2.35.3 > > > > -- > Peter Xu -- Peter Xu