Hi Philippe, How did you trigger this? What is the call stack? >From a first look, all callers of blk_all_next also call GLOBAL_STATE_CODE, except qmp_* functions.
That would be useful to understand if we need to change the function assertion and classification, or the caller is breaking some invariants. Thank you, Emanuele Am 16/03/2022 um 13:44 schrieb Philippe Mathieu-Daudé: > Hi, > > On 4/3/22 17:46, Kevin Wolf wrote: >> From: Emanuele Giuseppe Esposito <eespo...@redhat.com> >> >> All the global state (GS) API functions will check that >> qemu_in_main_thread() returns true. If not, it means >> that the safety of BQL cannot be guaranteed, and >> they need to be moved to I/O. > > I'm getting this crash: > > $ qemu-system-i386 > Assertion failed: (qemu_in_main_thread()), function blk_all_next, file > block-backend.c, line 552. > Abort trap: 6 > > Assertion failed: (qemu_in_main_thread()), function blk_all_next, file > block-backend.c, line 552. > qemu-system-i386 was compiled with optimization - stepping may behave > oddly; variables may not be available. > Process 76914 stopped > * thread #1, queue = 'com.apple.main-thread', stop reason = hit program > assert > frame #4: 0x000000010057c2d4 qemu-system-i386`blk_all_next.cold.1 at > block-backend.c:552:5 [opt] > 549 */ > 550 BlockBackend *blk_all_next(BlockBackend *blk) > 551 { > -> 552 GLOBAL_STATE_CODE(); > 553 return blk ? QTAILQ_NEXT(blk, link) > 554 : QTAILQ_FIRST(&block_backends); > 555 } > Target 1: (qemu-system-i386) stopped. > > Bisected to this patch: > > 0439c5a4623d674efa0c72abd62ca6e98bb7cf87 is the first bad commit > >> Signed-off-by: Emanuele Giuseppe Esposito <eespo...@redhat.com> >> Message-Id: <20220303151616.325444-9-eespo...@redhat.com> >> Signed-off-by: Kevin Wolf <kw...@redhat.com> >> --- >> block/block-backend.c | 78 ++++++++++++++++++++++++++++++++++++++++++ >> softmmu/qdev-monitor.c | 2 ++ >> 2 files changed, 80 insertions(+) >> >> diff --git a/block/block-backend.c b/block/block-backend.c >> index 462e18facf..4476b61b8b 100644 >> --- a/block/block-backend.c >> +++ b/block/block-backend.c >> @@ -239,6 +239,7 @@ static void blk_root_activate(BdrvChild *child, >> Error **errp) >> void blk_set_force_allow_inactivate(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> blk->force_allow_inactivate = true; >> } >> @@ -357,6 +358,8 @@ BlockBackend *blk_new(AioContext *ctx, uint64_t >> perm, uint64_t shared_perm) >> { >> BlockBackend *blk; >> + GLOBAL_STATE_CODE(); >> + >> blk = g_new0(BlockBackend, 1); >> blk->refcnt = 1; >> blk->ctx = ctx; >> @@ -394,6 +397,8 @@ BlockBackend *blk_new_with_bs(BlockDriverState >> *bs, uint64_t perm, >> { >> BlockBackend *blk = blk_new(bdrv_get_aio_context(bs), perm, >> shared_perm); >> + GLOBAL_STATE_CODE(); >> + >> if (blk_insert_bs(blk, bs, errp) < 0) { >> blk_unref(blk); >> return NULL; >> @@ -422,6 +427,8 @@ BlockBackend *blk_new_open(const char *filename, >> const char *reference, >> uint64_t perm = 0; >> uint64_t shared = BLK_PERM_ALL; >> + GLOBAL_STATE_CODE(); >> + >> /* >> * blk_new_open() is mainly used in .bdrv_create implementations >> and the >> * tools where sharing isn't a major concern because the BDS >> stays private >> @@ -499,6 +506,7 @@ static void drive_info_del(DriveInfo *dinfo) >> int blk_get_refcnt(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> return blk ? blk->refcnt : 0; >> } >> @@ -509,6 +517,7 @@ int blk_get_refcnt(BlockBackend *blk) >> void blk_ref(BlockBackend *blk) >> { >> assert(blk->refcnt > 0); >> + GLOBAL_STATE_CODE(); >> blk->refcnt++; >> } >> @@ -519,6 +528,7 @@ void blk_ref(BlockBackend *blk) >> */ >> void blk_unref(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> if (blk) { >> assert(blk->refcnt > 0); >> if (blk->refcnt > 1) { >> @@ -539,6 +549,7 @@ void blk_unref(BlockBackend *blk) >> */ >> BlockBackend *blk_all_next(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> return blk ? QTAILQ_NEXT(blk, link) >> : QTAILQ_FIRST(&block_backends); >> } >> @@ -547,6 +558,8 @@ void blk_remove_all_bs(void) >> { >> BlockBackend *blk = NULL; >> + GLOBAL_STATE_CODE(); >> + >> while ((blk = blk_all_next(blk)) != NULL) { >> AioContext *ctx = blk_get_aio_context(blk); >> @@ -570,6 +583,7 @@ void blk_remove_all_bs(void) >> */ >> BlockBackend *blk_next(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> return blk ? QTAILQ_NEXT(blk, monitor_link) >> : QTAILQ_FIRST(&monitor_block_backends); >> } >> @@ -636,6 +650,7 @@ static void bdrv_next_reset(BdrvNextIterator *it) >> BlockDriverState *bdrv_first(BdrvNextIterator *it) >> { >> + GLOBAL_STATE_CODE(); >> bdrv_next_reset(it); >> return bdrv_next(it); >> } >> @@ -673,6 +688,7 @@ bool monitor_add_blk(BlockBackend *blk, const char >> *name, Error **errp) >> { >> assert(!blk->name); >> assert(name && name[0]); >> + GLOBAL_STATE_CODE(); >> if (!id_wellformed(name)) { >> error_setg(errp, "Invalid device name"); >> @@ -700,6 +716,8 @@ bool monitor_add_blk(BlockBackend *blk, const char >> *name, Error **errp) >> */ >> void monitor_remove_blk(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> + >> if (!blk->name) { >> return; >> } >> @@ -726,6 +744,7 @@ BlockBackend *blk_by_name(const char *name) >> { >> BlockBackend *blk = NULL; >> + GLOBAL_STATE_CODE(); >> assert(name); >> while ((blk = blk_next(blk)) != NULL) { >> if (!strcmp(name, blk->name)) { >> @@ -760,6 +779,7 @@ static BlockBackend >> *bdrv_first_blk(BlockDriverState *bs) >> */ >> bool bdrv_has_blk(BlockDriverState *bs) >> { >> + GLOBAL_STATE_CODE(); >> return bdrv_first_blk(bs) != NULL; >> } >> @@ -770,6 +790,7 @@ bool bdrv_is_root_node(BlockDriverState *bs) >> { >> BdrvChild *c; >> + GLOBAL_STATE_CODE(); >> QLIST_FOREACH(c, &bs->parents, next_parent) { >> if (c->klass != &child_root) { >> return false; >> @@ -819,6 +840,7 @@ BlockBackend *blk_by_legacy_dinfo(DriveInfo *dinfo) >> */ >> BlockBackendPublic *blk_get_public(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> return &blk->public; >> } >> @@ -827,6 +849,7 @@ BlockBackendPublic *blk_get_public(BlockBackend >> *blk) >> */ >> BlockBackend *blk_by_public(BlockBackendPublic *public) >> { >> + GLOBAL_STATE_CODE(); >> return container_of(public, BlockBackend, public); >> } >> @@ -838,6 +861,8 @@ void blk_remove_bs(BlockBackend *blk) >> ThrottleGroupMember *tgm = &blk->public.throttle_group_member; >> BdrvChild *root; >> + GLOBAL_STATE_CODE(); >> + >> notifier_list_notify(&blk->remove_bs_notifiers, blk); >> if (tgm->throttle_state) { >> BlockDriverState *bs = blk_bs(blk); >> @@ -872,6 +897,7 @@ void blk_remove_bs(BlockBackend *blk) >> int blk_insert_bs(BlockBackend *blk, BlockDriverState *bs, Error >> **errp) >> { >> ThrottleGroupMember *tgm = &blk->public.throttle_group_member; >> + GLOBAL_STATE_CODE(); >> bdrv_ref(bs); >> blk->root = bdrv_root_attach_child(bs, "root", &child_root, >> BDRV_CHILD_FILTERED | >> BDRV_CHILD_PRIMARY, >> @@ -895,6 +921,7 @@ int blk_insert_bs(BlockBackend *blk, >> BlockDriverState *bs, Error **errp) >> */ >> int blk_replace_bs(BlockBackend *blk, BlockDriverState *new_bs, >> Error **errp) >> { >> + GLOBAL_STATE_CODE(); >> return bdrv_replace_child_bs(blk->root, new_bs, errp); >> } >> @@ -905,6 +932,7 @@ int blk_set_perm(BlockBackend *blk, uint64_t >> perm, uint64_t shared_perm, >> Error **errp) >> { >> int ret; >> + GLOBAL_STATE_CODE(); >> if (blk->root && !blk->disable_perm) { >> ret = bdrv_child_try_set_perm(blk->root, perm, shared_perm, >> errp); >> @@ -921,6 +949,7 @@ int blk_set_perm(BlockBackend *blk, uint64_t perm, >> uint64_t shared_perm, >> void blk_get_perm(BlockBackend *blk, uint64_t *perm, uint64_t >> *shared_perm) >> { >> + GLOBAL_STATE_CODE(); >> *perm = blk->perm; >> *shared_perm = blk->shared_perm; >> } >> @@ -931,6 +960,7 @@ void blk_get_perm(BlockBackend *blk, uint64_t >> *perm, uint64_t *shared_perm) >> */ >> int blk_attach_dev(BlockBackend *blk, DeviceState *dev) >> { >> + GLOBAL_STATE_CODE(); >> if (blk->dev) { >> return -EBUSY; >> } >> @@ -956,6 +986,7 @@ int blk_attach_dev(BlockBackend *blk, DeviceState >> *dev) >> void blk_detach_dev(BlockBackend *blk, DeviceState *dev) >> { >> assert(blk->dev == dev); >> + GLOBAL_STATE_CODE(); >> blk->dev = NULL; >> blk->dev_ops = NULL; >> blk->dev_opaque = NULL; >> @@ -969,6 +1000,7 @@ void blk_detach_dev(BlockBackend *blk, >> DeviceState *dev) >> */ >> DeviceState *blk_get_attached_dev(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> return blk->dev; >> } >> @@ -997,6 +1029,8 @@ BlockBackend *blk_by_dev(void *dev) >> { >> BlockBackend *blk = NULL; >> + GLOBAL_STATE_CODE(); >> + >> assert(dev != NULL); >> while ((blk = blk_all_next(blk)) != NULL) { >> if (blk->dev == dev) { >> @@ -1014,6 +1048,7 @@ BlockBackend *blk_by_dev(void *dev) >> void blk_set_dev_ops(BlockBackend *blk, const BlockDevOps *ops, >> void *opaque) >> { >> + GLOBAL_STATE_CODE(); >> blk->dev_ops = ops; >> blk->dev_opaque = opaque; >> @@ -1035,6 +1070,7 @@ void blk_set_dev_ops(BlockBackend *blk, const >> BlockDevOps *ops, >> */ >> void blk_dev_change_media_cb(BlockBackend *blk, bool load, Error >> **errp) >> { >> + GLOBAL_STATE_CODE(); >> if (blk->dev_ops && blk->dev_ops->change_media_cb) { >> bool tray_was_open, tray_is_open; >> Error *local_err = NULL; >> @@ -1126,6 +1162,7 @@ static void blk_root_resize(BdrvChild *child) >> void blk_iostatus_enable(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> blk->iostatus_enabled = true; >> blk->iostatus = BLOCK_DEVICE_IO_STATUS_OK; >> } >> @@ -1142,16 +1179,19 @@ bool blk_iostatus_is_enabled(const >> BlockBackend *blk) >> BlockDeviceIoStatus blk_iostatus(const BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> return blk->iostatus; >> } >> void blk_iostatus_disable(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> blk->iostatus_enabled = false; >> } >> void blk_iostatus_reset(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> if (blk_iostatus_is_enabled(blk)) { >> blk->iostatus = BLOCK_DEVICE_IO_STATUS_OK; >> } >> @@ -1358,6 +1398,7 @@ int blk_pwrite_zeroes(BlockBackend *blk, int64_t >> offset, >> int blk_make_zero(BlockBackend *blk, BdrvRequestFlags flags) >> { >> + GLOBAL_STATE_CODE(); >> return bdrv_make_zero(blk->root, flags); >> } >> @@ -1567,6 +1608,7 @@ BlockAIOCB *blk_aio_pwritev(BlockBackend *blk, >> int64_t offset, >> void blk_aio_cancel(BlockAIOCB *acb) >> { >> + GLOBAL_STATE_CODE(); >> bdrv_aio_cancel(acb); >> } >> @@ -1723,6 +1765,7 @@ int blk_flush(BlockBackend *blk) >> void blk_drain(BlockBackend *blk) >> { >> BlockDriverState *bs = blk_bs(blk); >> + GLOBAL_STATE_CODE(); >> if (bs) { >> bdrv_ref(bs); >> @@ -1743,6 +1786,8 @@ void blk_drain_all(void) >> { >> BlockBackend *blk = NULL; >> + GLOBAL_STATE_CODE(); >> + >> bdrv_drain_all_begin(); >> while ((blk = blk_all_next(blk)) != NULL) { >> @@ -1762,6 +1807,7 @@ void blk_drain_all(void) >> void blk_set_on_error(BlockBackend *blk, BlockdevOnError on_read_error, >> BlockdevOnError on_write_error) >> { >> + GLOBAL_STATE_CODE(); >> blk->on_read_error = on_read_error; >> blk->on_write_error = on_write_error; >> } >> @@ -1845,6 +1891,7 @@ void blk_error_action(BlockBackend *blk, >> BlockErrorAction action, >> bool blk_supports_write_perm(BlockBackend *blk) >> { >> BlockDriverState *bs = blk_bs(blk); >> + GLOBAL_STATE_CODE(); >> if (bs) { >> return !bdrv_is_read_only(bs); >> @@ -1865,6 +1912,7 @@ bool blk_is_writable(BlockBackend *blk) >> bool blk_is_sg(BlockBackend *blk) >> { >> BlockDriverState *bs = blk_bs(blk); >> + GLOBAL_STATE_CODE(); >> if (!bs) { >> return false; >> @@ -1880,12 +1928,14 @@ bool blk_enable_write_cache(BlockBackend *blk) >> void blk_set_enable_write_cache(BlockBackend *blk, bool wce) >> { >> + GLOBAL_STATE_CODE(); >> blk->enable_write_cache = wce; >> } >> void blk_activate(BlockBackend *blk, Error **errp) >> { >> BlockDriverState *bs = blk_bs(blk); >> + GLOBAL_STATE_CODE(); >> if (!bs) { >> error_setg(errp, "Device '%s' has no medium", blk->name); >> @@ -1936,6 +1986,7 @@ void blk_eject(BlockBackend *blk, bool eject_flag) >> int blk_get_flags(BlockBackend *blk) >> { >> BlockDriverState *bs = blk_bs(blk); >> + GLOBAL_STATE_CODE(); >> if (bs) { >> return bdrv_get_flags(bs); >> @@ -2005,6 +2056,7 @@ void *blk_blockalign(BlockBackend *blk, size_t >> size) >> bool blk_op_is_blocked(BlockBackend *blk, BlockOpType op, Error **errp) >> { >> BlockDriverState *bs = blk_bs(blk); >> + GLOBAL_STATE_CODE(); >> if (!bs) { >> return false; >> @@ -2016,6 +2068,7 @@ bool blk_op_is_blocked(BlockBackend *blk, >> BlockOpType op, Error **errp) >> void blk_op_unblock(BlockBackend *blk, BlockOpType op, Error *reason) >> { >> BlockDriverState *bs = blk_bs(blk); >> + GLOBAL_STATE_CODE(); >> if (bs) { >> bdrv_op_unblock(bs, op, reason); >> @@ -2025,6 +2078,7 @@ void blk_op_unblock(BlockBackend *blk, >> BlockOpType op, Error *reason) >> void blk_op_block_all(BlockBackend *blk, Error *reason) >> { >> BlockDriverState *bs = blk_bs(blk); >> + GLOBAL_STATE_CODE(); >> if (bs) { >> bdrv_op_block_all(bs, reason); >> @@ -2034,6 +2088,7 @@ void blk_op_block_all(BlockBackend *blk, Error >> *reason) >> void blk_op_unblock_all(BlockBackend *blk, Error *reason) >> { >> BlockDriverState *bs = blk_bs(blk); >> + GLOBAL_STATE_CODE(); >> if (bs) { >> bdrv_op_unblock_all(bs, reason); >> @@ -2093,6 +2148,7 @@ static int blk_do_set_aio_context(BlockBackend >> *blk, AioContext *new_context, >> int blk_set_aio_context(BlockBackend *blk, AioContext *new_context, >> Error **errp) >> { >> + GLOBAL_STATE_CODE(); >> return blk_do_set_aio_context(blk, new_context, true, errp); >> } >> @@ -2129,6 +2185,7 @@ void blk_add_aio_context_notifier(BlockBackend >> *blk, >> { >> BlockBackendAioNotifier *notifier; >> BlockDriverState *bs = blk_bs(blk); >> + GLOBAL_STATE_CODE(); >> notifier = g_new(BlockBackendAioNotifier, 1); >> notifier->attached_aio_context = attached_aio_context; >> @@ -2151,6 +2208,8 @@ void >> blk_remove_aio_context_notifier(BlockBackend *blk, >> BlockBackendAioNotifier *notifier; >> BlockDriverState *bs = blk_bs(blk); >> + GLOBAL_STATE_CODE(); >> + >> if (bs) { >> bdrv_remove_aio_context_notifier(bs, attached_aio_context, >> detach_aio_context, opaque); >> @@ -2171,11 +2230,13 @@ void >> blk_remove_aio_context_notifier(BlockBackend *blk, >> void blk_add_remove_bs_notifier(BlockBackend *blk, Notifier *notify) >> { >> + GLOBAL_STATE_CODE(); >> notifier_list_add(&blk->remove_bs_notifiers, notify); >> } >> void blk_add_insert_bs_notifier(BlockBackend *blk, Notifier *notify) >> { >> + GLOBAL_STATE_CODE(); >> notifier_list_add(&blk->insert_bs_notifiers, notify); >> } >> @@ -2238,6 +2299,7 @@ int blk_save_vmstate(BlockBackend *blk, const >> uint8_t *buf, >> int64_t pos, int size) >> { >> int ret; >> + GLOBAL_STATE_CODE(); >> if (!blk_is_available(blk)) { >> return -ENOMEDIUM; >> @@ -2257,6 +2319,7 @@ int blk_save_vmstate(BlockBackend *blk, const >> uint8_t *buf, >> int blk_load_vmstate(BlockBackend *blk, uint8_t *buf, int64_t pos, >> int size) >> { >> + GLOBAL_STATE_CODE(); >> if (!blk_is_available(blk)) { >> return -ENOMEDIUM; >> } >> @@ -2266,6 +2329,7 @@ int blk_load_vmstate(BlockBackend *blk, uint8_t >> *buf, int64_t pos, int size) >> int blk_probe_blocksizes(BlockBackend *blk, BlockSizes *bsz) >> { >> + GLOBAL_STATE_CODE(); >> if (!blk_is_available(blk)) { >> return -ENOMEDIUM; >> } >> @@ -2275,6 +2339,7 @@ int blk_probe_blocksizes(BlockBackend *blk, >> BlockSizes *bsz) >> int blk_probe_geometry(BlockBackend *blk, HDGeometry *geo) >> { >> + GLOBAL_STATE_CODE(); >> if (!blk_is_available(blk)) { >> return -ENOMEDIUM; >> } >> @@ -2288,6 +2353,7 @@ int blk_probe_geometry(BlockBackend *blk, >> HDGeometry *geo) >> */ >> void blk_update_root_state(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> assert(blk->root); >> blk->root_state.open_flags = blk->root->bs->open_flags; >> @@ -2300,6 +2366,7 @@ void blk_update_root_state(BlockBackend *blk) >> */ >> bool blk_get_detect_zeroes_from_root_state(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> return blk->root_state.detect_zeroes; >> } >> @@ -2309,17 +2376,20 @@ bool >> blk_get_detect_zeroes_from_root_state(BlockBackend *blk) >> */ >> int blk_get_open_flags_from_root_state(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> return blk->root_state.open_flags; >> } >> BlockBackendRootState *blk_get_root_state(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> return &blk->root_state; >> } >> int blk_commit_all(void) >> { >> BlockBackend *blk = NULL; >> + GLOBAL_STATE_CODE(); >> while ((blk = blk_all_next(blk)) != NULL) { >> AioContext *aio_context = blk_get_aio_context(blk); >> @@ -2344,6 +2414,7 @@ int blk_commit_all(void) >> /* throttling disk I/O limits */ >> void blk_set_io_limits(BlockBackend *blk, ThrottleConfig *cfg) >> { >> + GLOBAL_STATE_CODE(); >> throttle_group_config(&blk->public.throttle_group_member, cfg); >> } >> @@ -2352,6 +2423,7 @@ void blk_io_limits_disable(BlockBackend *blk) >> BlockDriverState *bs = blk_bs(blk); >> ThrottleGroupMember *tgm = &blk->public.throttle_group_member; >> assert(tgm->throttle_state); >> + GLOBAL_STATE_CODE(); >> if (bs) { >> bdrv_ref(bs); >> bdrv_drained_begin(bs); >> @@ -2367,12 +2439,14 @@ void blk_io_limits_disable(BlockBackend *blk) >> void blk_io_limits_enable(BlockBackend *blk, const char *group) >> { >> assert(!blk->public.throttle_group_member.throttle_state); >> + GLOBAL_STATE_CODE(); >> throttle_group_register_tgm(&blk->public.throttle_group_member, >> group, blk_get_aio_context(blk)); >> } >> void blk_io_limits_update_group(BlockBackend *blk, const char *group) >> { >> + GLOBAL_STATE_CODE(); >> /* this BB is not part of any group */ >> if (!blk->public.throttle_group_member.throttle_state) { >> return; >> @@ -2440,11 +2514,13 @@ static void blk_root_drained_end(BdrvChild >> *child, int *drained_end_counter) >> void blk_register_buf(BlockBackend *blk, void *host, size_t size) >> { >> + GLOBAL_STATE_CODE(); >> bdrv_register_buf(blk_bs(blk), host, size); >> } >> void blk_unregister_buf(BlockBackend *blk, void *host) >> { >> + GLOBAL_STATE_CODE(); >> bdrv_unregister_buf(blk_bs(blk), host); >> } >> @@ -2469,11 +2545,13 @@ int coroutine_fn >> blk_co_copy_range(BlockBackend *blk_in, int64_t off_in, >> const BdrvChild *blk_root(BlockBackend *blk) >> { >> + GLOBAL_STATE_CODE(); >> return blk->root; >> } >> int blk_make_empty(BlockBackend *blk, Error **errp) >> { >> + GLOBAL_STATE_CODE(); >> if (!blk_is_available(blk)) { >> error_setg(errp, "No medium inserted"); >> return -ENOMEDIUM; >> diff --git a/softmmu/qdev-monitor.c b/softmmu/qdev-monitor.c >> index 01f3834db5..ff14af8396 100644 >> --- a/softmmu/qdev-monitor.c >> +++ b/softmmu/qdev-monitor.c >> @@ -971,6 +971,8 @@ BlockBackend *blk_by_qdev_id(const char *id, Error >> **errp) >> DeviceState *dev; >> BlockBackend *blk; >> + GLOBAL_STATE_CODE(); >> + >> dev = find_device_state(id, errp); >> if (dev == NULL) { >> return NULL; >