When management applications (like Libvirt) want to check whether memory-backend-file.pmem is supported they can list object properties using 'qom-list-properties'. However, 'pmem' is declared always (and thus reported always) and only at runtime QEMU errors out if it was built without libpmem (and thus can not guarantee write persistence). This is suboptimal since we have ability to declare attributes at compile time.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1915216 Signed-off-by: Michal Privoznik <mpriv...@redhat.com> --- backends/hostmem-file.c | 13 ++++--------- 1 file changed, 4 insertions(+), 9 deletions(-) diff --git a/backends/hostmem-file.c b/backends/hostmem-file.c index 40e1e5b3e3..7e30eb5985 100644 --- a/backends/hostmem-file.c +++ b/backends/hostmem-file.c @@ -123,6 +123,7 @@ static void file_memory_backend_set_align(Object *o, Visitor *v, fb->align = val; } +#ifdef CONFIG_LIBPMEM static bool file_memory_backend_get_pmem(Object *o, Error **errp) { return MEMORY_BACKEND_FILE(o)->is_pmem; @@ -139,17 +140,9 @@ static void file_memory_backend_set_pmem(Object *o, bool value, Error **errp) return; } -#ifndef CONFIG_LIBPMEM - if (value) { - error_setg(errp, "Lack of libpmem support while setting the 'pmem=on'" - " of %s. We can't ensure data persistence.", - object_get_typename(o)); - return; - } -#endif - fb->is_pmem = value; } +#endif /* CONFIG_LIBPMEM */ static void file_backend_unparent(Object *obj) { @@ -180,8 +173,10 @@ file_backend_class_init(ObjectClass *oc, void *data) file_memory_backend_get_align, file_memory_backend_set_align, NULL, NULL); +#ifdef CONFIG_LIBPMEM object_class_property_add_bool(oc, "pmem", file_memory_backend_get_pmem, file_memory_backend_set_pmem); +#endif } static void file_backend_instance_finalize(Object *o) -- 2.26.2