Peter Xu <[email protected]> writes: > On Wed, Mar 13, 2024 at 10:50:18AM -0300, Fabiano Rosas wrote: >> The memory for the io channels is being leaked in three different ways >> during file migration: >> >> 1) if the offset check fails we never drop the ioc reference; >> >> 2) if multifd is not enabled, we allocate an extra channel for no >> reason; > > This leak should also happen even if multifd enabled; it just always leak > one unconditionally.. > >> >> 3) if multifd is enabled but channel creation fails when calling >> dup(), we leave the previous channels around along with the glib >> polling; >> >> Fix all issues by restructuring the code to first allocate the >> channels and only register the watches when all channels have been >> created. >> >> The file and fd migrations can share this code because both are backed >> by the file migration infrastructure. >> >> Fixes: 2dd7ee7a51 ("migration/multifd: Add incoming QIOChannelFile support") >> Fixes: decdc76772 ("migration/multifd: Add mapped-ram support to fd: URI") >> Reported-by: Peter Xu <[email protected]> >> Signed-off-by: Fabiano Rosas <[email protected]> >> --- >> based-on: https://gitlab.com/peterx/migration-stable > > Invalid link. :)
lol, all kinds of wrong. The correct one would be: https://gitlab.com/peterx/qemu/-/commits/migration-stable > > I am not sure whether patchew will understand this even if the link is > correct, but I hope! I was thinking more of helping reviewers than patchew actually. > >> CI run: https://gitlab.com/farosas/qemu/-/pipelines/1211909831 >> --- >> migration/fd.c | 28 +++------------------- >> migration/file.c | 62 +++++++++++++++++++++++++++++++----------------- >> migration/file.h | 3 +++ >> 3 files changed, 46 insertions(+), 47 deletions(-) >> >> diff --git a/migration/fd.c b/migration/fd.c >> index 4e2a63a73d..b74a3eb8c8 100644 >> --- a/migration/fd.c >> +++ b/migration/fd.c >> @@ -18,6 +18,7 @@ >> #include "qapi/error.h" >> #include "channel.h" >> #include "fd.h" >> +#include "file.h" >> #include "migration.h" >> #include "monitor/monitor.h" >> #include "io/channel-file.h" >> @@ -68,19 +69,9 @@ void fd_start_outgoing_migration(MigrationState *s, const >> char *fdname, Error ** >> object_unref(OBJECT(ioc)); >> } >> >> -static gboolean fd_accept_incoming_migration(QIOChannel *ioc, >> - GIOCondition condition, >> - gpointer opaque) >> -{ >> - migration_channel_process_incoming(ioc); >> - object_unref(OBJECT(ioc)); >> - return G_SOURCE_REMOVE; >> -} >> - >> void fd_start_incoming_migration(const char *fdname, Error **errp) >> { >> QIOChannel *ioc; >> - QIOChannelFile *fioc; >> int fd = monitor_fd_param(monitor_cur(), fdname, errp); >> if (fd == -1) { >> return; >> @@ -96,24 +87,11 @@ void fd_start_incoming_migration(const char *fdname, >> Error **errp) >> >> qio_channel_set_name(ioc, "migration-fd-incoming"); >> qio_channel_add_watch_full(ioc, G_IO_IN, >> - fd_accept_incoming_migration, >> + file_accept_incoming_migration, >> NULL, NULL, >> g_main_context_get_thread_default()); > > Mostly correct, but IIUC we'll still leak this main io watch if below > failed, similar issue for file path below. We may need to manage all IOCs > including the main one. > Yes, good point. Sigh... I'll get it right eventually. >> >> if (migrate_multifd()) { >> - int channels = migrate_multifd_channels(); >> - >> - while (channels--) { >> - fioc = qio_channel_file_new_dupfd(fd, errp); >> - if (!fioc) { >> - return; >> - } >> - >> - qio_channel_set_name(ioc, "migration-fd-incoming"); >> - qio_channel_add_watch_full(QIO_CHANNEL(fioc), G_IO_IN, >> - fd_accept_incoming_migration, >> - NULL, NULL, >> - g_main_context_get_thread_default()); >> - } >> + file_recv_channels_create(fd, errp); >> } >> } >> diff --git a/migration/file.c b/migration/file.c >> index e56c5eb0a5..bb264115eb 100644 >> --- a/migration/file.c >> +++ b/migration/file.c >> @@ -106,22 +106,48 @@ void file_start_outgoing_migration(MigrationState *s, >> migration_channel_connect(s, ioc, NULL, NULL); >> } >> >> -static gboolean file_accept_incoming_migration(QIOChannel *ioc, >> - GIOCondition condition, >> - gpointer opaque) >> +gboolean file_accept_incoming_migration(QIOChannel *ioc, GIOCondition >> condition, >> + gpointer opaque) >> { >> migration_channel_process_incoming(ioc); >> object_unref(OBJECT(ioc)); >> return G_SOURCE_REMOVE; >> } >> >> +void file_recv_channels_create(int fd, Error **errp) >> +{ >> + int i, channels = migrate_multifd_channels(); >> + g_autofree QIOChannelFile **fiocs = g_new0(QIOChannelFile *, channels); >> + >> + for (i = 0; i < channels; i++) { >> + QIOChannelFile *fioc = qio_channel_file_new_dupfd(fd, errp); >> + >> + if (!fioc) { >> + while (i) { >> + object_unref(fiocs[--i]); >> + } >> + return; >> + } >> + >> + fiocs[i] = fioc; >> + } >> + >> + for (i = 0; i < channels; i++) { >> + QIOChannelFile *fioc = fiocs[i]; >> + >> + qio_channel_set_name(QIO_CHANNEL(fioc), "migration-file-incoming"); >> + qio_channel_add_watch_full(QIO_CHANNEL(fioc), G_IO_IN, >> + file_accept_incoming_migration, >> + NULL, NULL, >> + g_main_context_get_thread_default()); >> + } >> +} >> + >> void file_start_incoming_migration(FileMigrationArgs *file_args, Error >> **errp) >> { >> g_autofree char *filename = g_strdup(file_args->filename); >> QIOChannelFile *fioc = NULL; >> uint64_t offset = file_args->offset; >> - int channels = 1; >> - int i = 0; >> >> trace_migration_file_incoming(filename); >> >> @@ -132,28 +158,20 @@ void file_start_incoming_migration(FileMigrationArgs >> *file_args, Error **errp) >> >> if (offset && >> qio_channel_io_seek(QIO_CHANNEL(fioc), offset, SEEK_SET, errp) < 0) >> { >> + object_unref(OBJECT(fioc)); >> return; >> } >> >> + qio_channel_set_name(QIO_CHANNEL(fioc), "migration-file-incoming"); >> + qio_channel_add_watch_full(QIO_CHANNEL(fioc), G_IO_IN, >> + file_accept_incoming_migration, >> + NULL, NULL, >> + g_main_context_get_thread_default()); >> + >> + >> if (migrate_multifd()) { >> - channels += migrate_multifd_channels(); >> + file_recv_channels_create(fioc->fd, errp); >> } >> - >> - do { >> - QIOChannel *ioc = QIO_CHANNEL(fioc); >> - >> - qio_channel_set_name(ioc, "migration-file-incoming"); >> - qio_channel_add_watch_full(ioc, G_IO_IN, >> - file_accept_incoming_migration, >> - NULL, NULL, >> - g_main_context_get_thread_default()); >> - >> - fioc = qio_channel_file_new_dupfd(fioc->fd, errp); >> - >> - if (!fioc) { >> - break; >> - } >> - } while (++i < channels); >> } >> >> int file_write_ramblock_iov(QIOChannel *ioc, const struct iovec *iov, >> diff --git a/migration/file.h b/migration/file.h >> index 9f71e87f74..940122db0f 100644 >> --- a/migration/file.h >> +++ b/migration/file.h >> @@ -20,6 +20,9 @@ void file_start_outgoing_migration(MigrationState *s, >> int file_parse_offset(char *filespec, uint64_t *offsetp, Error **errp); >> void file_cleanup_outgoing_migration(void); >> bool file_send_channel_create(gpointer opaque, Error **errp); >> +void file_recv_channels_create(int fd, Error **errp); >> +gboolean file_accept_incoming_migration(QIOChannel *ioc, GIOCondition >> condition, >> + gpointer opaque); >> int file_write_ramblock_iov(QIOChannel *ioc, const struct iovec *iov, >> int niov, RAMBlock *block, Error **errp); >> int multifd_file_recv_data(MultiFDRecvParams *p, Error **errp); >> -- >> 2.35.3 >>
