From: Christoph Hellwig <hch@lst.de> mainline inclusion from mainline-v6.0-rc1 commit c57094a6e1ed5dd2d6401f79b8e6da34dd28f959 category: bugfix bugzilla: 188733, https://gitee.com/openeuler/kernel/issues/I81XCK Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... ------------------------------------------------- Error handling in md_alloc is a mess. Untangle it to just free the mddev directly before add_disk is called and thus the gendisk is globally visible. After that clear the hold flag and let the mddev_put take care of cleaning up the mddev through the usual mechanisms. Fixes: 5e55e2f5fc95 ("[PATCH] md: convert compile time warnings into runtime warnings") Fixes: 9be68dd7ac0e ("md: add error handling support for add_disk()") Fixes: 7ad1069166c0 ("md: properly unwind when failing to add the kobject in md_alloc") Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Conflict: drivers/md/md.c Commit 0d809b3837a0 ("md: do not return existing mddevs from mddev_find_or_alloc") introduce mddev_alloc(). Fix conflict by dropping the error handle of it and label out_unlock, goto done if mddev->gendisk exists. Commit 8b9ab6266204 ("block: remove blk_cleanup_disk") change blk_cleanup_disk() to put_disk(). Keep using blk_cleanup_disk(), Signed-off-by: Li Nan <linan122@huawei.com> --- drivers/md/md.c | 42 ++++++++++++++++++++++++++++++------------ 1 file changed, 30 insertions(+), 12 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 33905999bb05..bf9a08a9af8a 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -5731,6 +5731,15 @@ int mddev_init_writes_pending(struct mddev *mddev) } EXPORT_SYMBOL_GPL(mddev_init_writes_pending); +static void mddev_free(struct mddev *mddev) +{ + spin_lock(&all_mddevs_lock); + list_del(&mddev->all_mddevs); + spin_unlock(&all_mddevs_lock); + + kfree(mddev); +} + static int md_alloc(dev_t dev, char *name) { /* @@ -5766,7 +5775,7 @@ static int md_alloc(dev_t dev, char *name) mutex_lock(&disks_mutex); error = -EEXIST; if (mddev->gendisk) - goto out_unlock_disks_mutex; + goto done; if (name && !dev) { /* Need to ensure that 'name' is not a duplicate. @@ -5778,7 +5787,7 @@ static int md_alloc(dev_t dev, char *name) if (mddev2->gendisk && strcmp(mddev2->gendisk->disk_name, name) == 0) { spin_unlock(&all_mddevs_lock); - goto out_unlock_disks_mutex; + goto out_free_mddev; } spin_unlock(&all_mddevs_lock); } @@ -5791,7 +5800,7 @@ static int md_alloc(dev_t dev, char *name) error = -ENOMEM; disk = blk_alloc_disk(NUMA_NO_NODE); if (!disk) - goto out_unlock_disks_mutex; + goto out_free_mddev; disk->major = MAJOR(mddev->unit); disk->first_minor = unit << shift; @@ -5817,26 +5826,35 @@ static int md_alloc(dev_t dev, char *name) mddev->gendisk = disk; error = add_disk_safe(disk); if (error) - goto out_cleanup_disk; + goto out_put_disk; kobject_init(&mddev->kobj, &md_ktype); error = kobject_add(&mddev->kobj, &disk_to_dev(disk)->kobj, "%s", "md"); - if (error) - goto out_del_gendisk; + if (error) { + /* + * The disk is already live at this point. Clear the hold flag + * and let mddev_put take care of the deletion, as it isn't any + * different from a normal close on last release now. + */ + mddev->hold_active = 0; + goto done; + } kobject_uevent(&mddev->kobj, KOBJ_ADD); mddev->sysfs_state = sysfs_get_dirent_safe(mddev->kobj.sd, "array_state"); mddev->sysfs_level = sysfs_get_dirent_safe(mddev->kobj.sd, "level"); - goto out_unlock_disks_mutex; -out_del_gendisk: - del_gendisk(disk); -out_cleanup_disk: - blk_cleanup_disk(disk); -out_unlock_disks_mutex: +done: mutex_unlock(&disks_mutex); mddev_put(mddev); return error; + +out_put_disk: + blk_cleanup_disk(disk); +out_free_mddev: + mddev_free(mddev); + mutex_unlock(&disks_mutex); + return error; } static struct kobject *md_probe(dev_t dev, int *part, void *data) -- 2.39.2