{"id":2227467,"url":"http://patchwork.ozlabs.org/api/1.2/patches/2227467/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260423191958.1440-31-farosas@suse.de/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/1.2/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":"","list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<20260423191958.1440-31-farosas@suse.de>","list_archive_url":null,"date":"2026-04-23T19:19:44","name":"[PULL,30/43] vmstate: Allow vmstate_info_nullptr to emit non-NULL markers","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"b6d28a6d8b6dcd972c013a526f9dde223b4da696","submitter":{"id":85343,"url":"http://patchwork.ozlabs.org/api/1.2/people/85343/?format=json","name":"Fabiano Rosas","email":"farosas@suse.de"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260423191958.1440-31-farosas@suse.de/mbox/","series":[{"id":501236,"url":"http://patchwork.ozlabs.org/api/1.2/series/501236/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=501236","date":"2026-04-23T19:19:14","name":"[PULL,01/43] checkpatch: Allow spaces after all coroutine annotations","version":1,"mbox":"http://patchwork.ozlabs.org/series/501236/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2227467/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2227467/checks/","tags":{},"related":[],"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (1024-bit key;\n unprotected) header.d=suse.de header.i=@suse.de header.a=rsa-sha256\n header.s=susede2_rsa header.b=IGMohvtO;\n\tdkim=pass header.d=suse.de header.i=@suse.de header.a=ed25519-sha256\n header.s=susede2_ed25519 header.b=wMVwALrU;\n\tdkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de\n header.a=rsa-sha256 header.s=susede2_rsa header.b=IGMohvtO;\n\tdkim=neutral header.d=suse.de header.i=@suse.de header.a=ed25519-sha256\n header.s=susede2_ed25519 header.b=wMVwALrU;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org\n (client-ip=209.51.188.17; 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t=1776972047;\n h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc:\n mime-version:mime-version:\n content-transfer-encoding:content-transfer-encoding:\n in-reply-to:in-reply-to:references:references;\n bh=cEY8XD3xBrJLvWZZxM6SWztn1MCt3QZRKtvPcKEo8uk=;\n b=wMVwALrUh4v++CbqwZx6Ye7u9WydyDriXrIIua7e4uKHUJWIaxgIMIIXzqwK5k59kEBz4H\n /8a61Z98tJVgBwBA=="],"From":"Fabiano Rosas ","To":"qemu-devel@nongnu.org","Cc":"Peter Xu ,\n Alexander Mikhalitsyn ,\n Juraj Marcin ","Subject":"[PULL 30/43] vmstate: Allow vmstate_info_nullptr to emit non-NULL\n markers","Date":"Thu, 23 Apr 2026 16:19:44 -0300","Message-ID":"<20260423191958.1440-31-farosas@suse.de>","X-Mailer":"git-send-email 2.51.0","In-Reply-To":"<20260423191958.1440-1-farosas@suse.de>","References":"<20260423191958.1440-1-farosas@suse.de>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","X-Spamd-Result":"default: False [-2.80 / 50.00]; BAYES_HAM(-3.00)[100.00%];\n NEURAL_HAM_LONG(-1.00)[-1.000]; MID_CONTAINS_FROM(1.00)[];\n R_MISSING_CHARSET(0.50)[]; 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VMS_MARKER_PTR_VALID : VMS_MARKER_PTR_NULL);\n+ return true;\n }\n \n-const VMStateInfo vmstate_info_nullptr = {\n- .name = \"nullptr\",\n- .load = load_nullptr,\n- .save = save_nullptr,\n+const VMStateInfo vmstate_info_ptr_marker = {\n+ .name = \"ptr-marker\",\n+ .load = load_ptr_marker,\n+ .save = save_ptr_marker,\n };\n \n /* 64 bit unsigned int. See that the received value is the same than the one\ndiff --git a/migration/vmstate.c b/migration/vmstate.c\nindex b274204e66..b333aa1744 100644\n--- a/migration/vmstate.c\n+++ b/migration/vmstate.c\n@@ -55,12 +55,12 @@ vmstate_field_exists(const VMStateDescription *vmsd, const VMStateField *field,\n }\n \n /*\n- * Create a fake nullptr field when there's a NULL pointer detected in the\n+ * Create a ptr marker field when there's a NULL pointer detected in the\n * array of a VMS_ARRAY_OF_POINTER VMSD field. It's needed because we\n * can't dereference the NULL pointer.\n */\n static const VMStateField *\n-vmsd_create_fake_nullptr_field(const VMStateField *field)\n+vmsd_create_ptr_marker_field(const VMStateField *field)\n {\n VMStateField *fake = g_new0(VMStateField, 1);\n \n@@ -71,12 +71,12 @@ vmsd_create_fake_nullptr_field(const VMStateField *field)\n fake->name = field->name;\n fake->version_id = field->version_id;\n \n- /* Do not need \"field_exists\" check as it always exists (which is null) */\n+ /* Do not need \"field_exists\" check as it always exists */\n fake->field_exists = NULL;\n \n- /* See vmstate_info_nullptr - use 1 byte to represent nullptr */\n+ /* See vmstate_info_ptr_marker - use 1 byte to represent ptr status */\n fake->size = 1;\n- fake->info = &vmstate_info_nullptr;\n+ fake->info = &vmstate_info_ptr_marker;\n fake->flags = VMS_SINGLE;\n \n /* All the rest fields shouldn't matter.. */\n@@ -278,7 +278,7 @@ bool vmstate_load_vmsd(QEMUFile *f, const VMStateDescription *vmsd,\n * an array of pointers), use null placeholder and do\n * not follow.\n */\n- inner_field = vmsd_create_fake_nullptr_field(field);\n+ inner_field = vmsd_create_ptr_marker_field(field);\n } else {\n inner_field = field;\n }\n@@ -583,26 +583,27 @@ static bool vmstate_save_vmsd_v(QEMUFile *f, const VMStateDescription *vmsd,\n for (i = 0; i < n_elems; i++) {\n void *curr_elem = first_elem + size * i;\n const VMStateField *inner_field;\n- bool is_null;\n /* maximum number of elements to compress in the JSON blob */\n int max_elems = vmsd_can_compress(field) ? (n_elems - i) : 1;\n+ bool use_marker_field, is_null;\n \n if (field->flags & VMS_ARRAY_OF_POINTER) {\n assert(curr_elem);\n curr_elem = *(void **)curr_elem;\n }\n \n- if (!curr_elem && size) {\n+ is_null = !curr_elem && size;\n+ use_marker_field = is_null;\n+\n+ if (use_marker_field) {\n /*\n * If null pointer found (which should only happen in\n * an array of pointers), use null placeholder and do\n * not follow.\n */\n- inner_field = vmsd_create_fake_nullptr_field(field);\n- is_null = true;\n+ inner_field = vmsd_create_ptr_marker_field(field);\n } else {\n inner_field = field;\n- is_null = false;\n }\n \n /*\n@@ -638,7 +639,7 @@ static bool vmstate_save_vmsd_v(QEMUFile *f, const VMStateDescription *vmsd,\n i, max_elems, errp);\n \n /* If we used a fake temp field.. free it now */\n- if (is_null) {\n+ if (use_marker_field) {\n g_clear_pointer((gpointer *)&inner_field, g_free);\n }\n \ndiff --git a/scripts/analyze-migration.py b/scripts/analyze-migration.py\nindex e81deab8f9..1771ff781b 100755\n--- a/scripts/analyze-migration.py\n+++ b/scripts/analyze-migration.py\n@@ -469,26 +469,26 @@ def __init__(self, desc, file):\n super(VMSDFieldIntLE, self).__init__(desc, file)\n self.dtype = '